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Leung E, Patel J, Hollywood JA, Zafar A, Tomek P, Barker D, Pilkington LI, van Rensburg M, Langley RJ, Helsby NA, Squire CJ, Baguley BC, Denny WA, Reynisson J, Leung IKH. Validating TDP1 as an Inhibition Target for the Development of Chemosensitizers for Camptothecin-Based Chemotherapy Drugs. Oncol Ther 2021; 9:541-556. [PMID: 34159519 PMCID: PMC8593127 DOI: 10.1007/s40487-021-00158-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 06/03/2021] [Indexed: 12/01/2022] Open
Abstract
Cancer chemotherapy sensitizers hold the key to maximizing the potential of standard anticancer treatments. We have a long-standing interest in developing and validating inhibitors of the DNA repair enzyme tyrosyl-DNA phosphodiesterase 1 (TDP1) as chemosensitizers for topoisomerase I poisons such as topotecan. Herein, by using thieno[2,3-b]pyridines, a class of TDP1 inhibitors, we showed that the inhibition of TDP1 can restore sensitivity to topotecan, results that are supported by TDP1 knockout cell experiments using CRISPR/Cas9. However, we also found that the restored sensitivity towards topoisomerase I inhibitors is likely regulated by multiple complementary DNA repair pathways. Our results showed that one of these pathways is likely modulated by PARP1, although it is also possible that other redundant and partially overlapping pathways may be involved in the DNA repair process. Our work thus raises the prospect of targeting multiple DNA repair pathways to increase the sensitivity to topoisomerase I inhibitors.
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Affiliation(s)
- Euphemia Leung
- Auckland Cancer Society Research Centre, School of Medical Sciences, The University of Auckland, Private Bag 92019, Victoria Street West, Auckland, 1142, New Zealand. .,Department of Molecular Medicine and Pathology, School of Medical Sciences, The University of Auckland, Private Bag 92019, Victoria Street West, Auckland, 1142, New Zealand. .,Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Private Bag 92019, Victoria Street West, Auckland, 1142, New Zealand.
| | - Jinal Patel
- School of Chemical Sciences, The University of Auckland, Private Bag 92019, Victoria Street West, Auckland, 1142, New Zealand
| | - Jennifer A Hollywood
- Department of Molecular Medicine and Pathology, School of Medical Sciences, The University of Auckland, Private Bag 92019, Victoria Street West, Auckland, 1142, New Zealand
| | - Ayesha Zafar
- School of Chemical Sciences, The University of Auckland, Private Bag 92019, Victoria Street West, Auckland, 1142, New Zealand
| | - Petr Tomek
- Auckland Cancer Society Research Centre, School of Medical Sciences, The University of Auckland, Private Bag 92019, Victoria Street West, Auckland, 1142, New Zealand
| | - David Barker
- School of Chemical Sciences, The University of Auckland, Private Bag 92019, Victoria Street West, Auckland, 1142, New Zealand.,The MacDiarmid Institute for Advanced Materials and Nanotechnology, Victoria University of Wellington, PO Box 600, Wellington, 6140, New Zealand
| | - Lisa I Pilkington
- School of Chemical Sciences, The University of Auckland, Private Bag 92019, Victoria Street West, Auckland, 1142, New Zealand
| | - Michelle van Rensburg
- School of Chemical Sciences, The University of Auckland, Private Bag 92019, Victoria Street West, Auckland, 1142, New Zealand
| | - Ries J Langley
- Department of Molecular Medicine and Pathology, School of Medical Sciences, The University of Auckland, Private Bag 92019, Victoria Street West, Auckland, 1142, New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Private Bag 92019, Victoria Street West, Auckland, 1142, New Zealand
| | - Nuala A Helsby
- Department of Molecular Medicine and Pathology, School of Medical Sciences, The University of Auckland, Private Bag 92019, Victoria Street West, Auckland, 1142, New Zealand
| | - Christopher J Squire
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Private Bag 92019, Victoria Street West, Auckland, 1142, New Zealand.,School of Biological Sciences, The University of Auckland, Private Bag 92019, Victoria Street West, Auckland, 1142, New Zealand
| | - Bruce C Baguley
- Auckland Cancer Society Research Centre, School of Medical Sciences, The University of Auckland, Private Bag 92019, Victoria Street West, Auckland, 1142, New Zealand
| | - William A Denny
- Auckland Cancer Society Research Centre, School of Medical Sciences, The University of Auckland, Private Bag 92019, Victoria Street West, Auckland, 1142, New Zealand
| | - Jóhannes Reynisson
- School of Chemical Sciences, The University of Auckland, Private Bag 92019, Victoria Street West, Auckland, 1142, New Zealand. .,School of Pharmacy and Bioengineering, Keele University, Staffordshire, ST5 5BG, UK.
| | - Ivanhoe K H Leung
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Private Bag 92019, Victoria Street West, Auckland, 1142, New Zealand. .,School of Chemical Sciences, The University of Auckland, Private Bag 92019, Victoria Street West, Auckland, 1142, New Zealand. .,School of Chemistry, The University of Melbourne, Parkville, VIC, 3010, Australia. .,Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC, 3010, Australia.
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2
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Rodger EJ, Almomani SN, Ludgate JL, Stockwell PA, Baguley BC, Eccles MR, Chatterjee A. Comparison of Global DNA Methylation Patterns in Human Melanoma Tissues and Their Derivative Cell Lines. Cancers (Basel) 2021; 13:cancers13092123. [PMID: 33924927 PMCID: PMC8124222 DOI: 10.3390/cancers13092123] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 04/19/2021] [Accepted: 04/22/2021] [Indexed: 12/20/2022] Open
Abstract
Simple Summary Cancer cell lines are a defined population of cells, originally sourced from tumour tissue, that can be maintained in culture for an extended period of time. They are a critical laboratory-based model, and are frequently used to unravel mechanisms of cancer cell biology. In all cells, gene activity is in part regulated by DNA methylation, the epigenetic process by which methyl groups are added to DNA. In this study, we demonstrate that at a global level, DNA methylation profiles are globally well conserved, but we identify specific sites that are consistently more methylated in tumour-derived cell lines compared to the original tumour tissue. The genes associated with these common differentially methylated regions are involved in important cellular processes and are strongly enriched for epigenetic mechanisms associated with suppression of gene activity. This study provides a valuable resource for identifying false positives due to cell culture and for better interpretation of future cancer epigenetics studies. Abstract DNA methylation is a heritable epigenetic mark that is fundamental to mammalian development. Aberrant DNA methylation is an epigenetic hallmark of cancer cells. Cell lines are a critical in vitro model and very widely used to unravel mechanisms of cancer cell biology. However, limited data are available to assess whether DNA methylation patterns in tissues are retained when cell lines are established. Here, we provide the first genome-scale sequencing-based methylation map of metastatic melanoma tumour tissues and their derivative cell lines. We show that DNA methylation profiles are globally conserved in vitro compared to the tumour tissue of origin. However, we identify sites that are consistently hypermethylated in cell lines compared to their tumour tissue of origin. The genes associated with these common differentially methylated regions are involved in cell metabolism, cell cycle and apoptosis and are also strongly enriched for the H3K27me3 histone mark and PRC2 complex-related genes. Our data indicate that although global methylation patterns are similar between tissues and cell lines, there are site-specific epigenomic differences that could potentially impact gene expression. Our work provides a valuable resource for identifying false positives due to cell culture and for better interpretation of cancer epigenetics studies in the future.
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Affiliation(s)
- Euan J. Rodger
- Department of Pathology, Otago Medical School—Dunedin Campus, University of Otago, Dunedin 9054, New Zealand; (S.N.A.); (J.L.L.); (P.A.S.)
- Maurice Wilkins Centre for Molecular Biodiscovery, Auckland 1010, New Zealand;
- Correspondence: (E.J.R.); (M.R.E.); (A.C.)
| | - Suzan N. Almomani
- Department of Pathology, Otago Medical School—Dunedin Campus, University of Otago, Dunedin 9054, New Zealand; (S.N.A.); (J.L.L.); (P.A.S.)
- Maurice Wilkins Centre for Molecular Biodiscovery, Auckland 1010, New Zealand;
| | - Jackie L. Ludgate
- Department of Pathology, Otago Medical School—Dunedin Campus, University of Otago, Dunedin 9054, New Zealand; (S.N.A.); (J.L.L.); (P.A.S.)
| | - Peter A. Stockwell
- Department of Pathology, Otago Medical School—Dunedin Campus, University of Otago, Dunedin 9054, New Zealand; (S.N.A.); (J.L.L.); (P.A.S.)
| | - Bruce C. Baguley
- Maurice Wilkins Centre for Molecular Biodiscovery, Auckland 1010, New Zealand;
| | - Michael R. Eccles
- Department of Pathology, Otago Medical School—Dunedin Campus, University of Otago, Dunedin 9054, New Zealand; (S.N.A.); (J.L.L.); (P.A.S.)
- Maurice Wilkins Centre for Molecular Biodiscovery, Auckland 1010, New Zealand;
- Correspondence: (E.J.R.); (M.R.E.); (A.C.)
| | - Aniruddha Chatterjee
- Department of Pathology, Otago Medical School—Dunedin Campus, University of Otago, Dunedin 9054, New Zealand; (S.N.A.); (J.L.L.); (P.A.S.)
- Maurice Wilkins Centre for Molecular Biodiscovery, Auckland 1010, New Zealand;
- Correspondence: (E.J.R.); (M.R.E.); (A.C.)
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3
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Motwani J, Rodger EJ, Stockwell PA, Baguley BC, Macaulay EC, Eccles MR. Genome-wide DNA methylation and RNA expression differences correlate with invasiveness in melanoma cell lines. Epigenomics 2021; 13:577-598. [PMID: 33781093 DOI: 10.2217/epi-2020-0440] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Aims & objectives: The aim of this study was to investigate the role of DNA methylation in invasiveness in melanoma cells. Materials & methods: The authors carried out genome-wide transcriptome (RNA sequencing) and reduced representation bisulfite sequencing methylome profiling between noninvasive (n = 4) and invasive melanoma cell lines (n = 5). Results: The integration of differentially expressed genes and differentially methylated fragments (DMFs) identified 12 DMFs (two in AVPI1, one in HMG20B, two in BCL3, one in NTSR1, one in SYNJ2, one in ROBO2 and four in HORMAD2) that overlapped with either differentially expressed genes (eight DMFs and six genes) or cis-targets of lncRNAs (five DMFs associated with cis-targets and four differentially expressed lncRNAs). Conclusions: DNA methylation changes are associated with a number of transcriptional differences observed in noninvasive and invasive phenotypes in melanoma.
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Affiliation(s)
- Jyoti Motwani
- Department of Pathology, Otago Medical School - Dunedin Campus, University of Otago, Dunedin 9054, New Zealand
| | - Euan J Rodger
- Department of Pathology, Otago Medical School - Dunedin Campus, University of Otago, Dunedin 9054, New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery, Level 2, 3A Symonds Street, Auckland 1010, New Zealand
| | - Peter A Stockwell
- Department of Pathology, Otago Medical School - Dunedin Campus, University of Otago, Dunedin 9054, New Zealand
| | - Bruce C Baguley
- Maurice Wilkins Centre for Molecular Biodiscovery, Level 2, 3A Symonds Street, Auckland 1010, New Zealand.,Auckland Cancer Society Research Centre, The University of Auckland, Auckland 1023, New Zealand
| | - Erin C Macaulay
- Department of Pathology, Otago Medical School - Dunedin Campus, University of Otago, Dunedin 9054, New Zealand
| | - Michael R Eccles
- Department of Pathology, Otago Medical School - Dunedin Campus, University of Otago, Dunedin 9054, New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery, Level 2, 3A Symonds Street, Auckland 1010, New Zealand
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4
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Tran KB, Kolekar S, Jabed A, Jaynes P, Shih JH, Wang Q, Flanagan JU, Rewcastle GW, Baguley BC, Shepherd PR. Diverse mechanisms activate the PI 3-kinase/mTOR pathway in melanomas: implications for the use of PI 3-kinase inhibitors to overcome resistance to inhibitors of BRAF and MEK. BMC Cancer 2021; 21:136. [PMID: 33549048 PMCID: PMC7866738 DOI: 10.1186/s12885-021-07826-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 01/20/2021] [Indexed: 12/11/2022] Open
Abstract
Background The PI 3-kinase (PI3K) pathway has been implicated as a target for melanoma therapy. Methods Given the high degree of genetic heterogeneity in melanoma, we sought to understand the breadth of variation in PI3K signalling in the large NZM panel of early passage cell lines developed from metastatic melanomas. Results We find the vast majority of lines show upregulation of this pathway, and this upregulation is achieved by a wide range of mechanisms. Expression of all class-IA PI3K isoforms was readily detected in these cell lines. A range of genetic changes in different components of the PI3K pathway was seen in different lines. Coding variants or amplification were identified in the PIK3CA gene, and amplification of the PK3CG gene was common. Deletions in the PIK3R1 and PIK3R2 regulatory subunits were also relatively common. Notably, no genetic variants were seen in the PIK3CD gene despite p110δ being expressed in many of the lines. Genetic variants were detected in a number of genes that encode phosphatases regulating the PI3K signalling, with reductions in copy number common in PTEN, INPP4B, INPP5J, PHLLP1 and PHLLP2 genes. While the pan-PI3K inhibitor ZSTK474 attenuated cell growth in all the lines tested, isoform-selective inhibition of p110α and p110δ inhibited cell growth in only a subset of the lines and the inhibition was only partial. This suggests that functional redundancy exists between PI3K isoforms. Furthermore, while ZSTK474 was initially effective in melanoma cells with induced resistance to vemurafenib, a subset of these cell lines concurrently developed partial resistance to PI3K inhibition. Importantly, mTOR-selective or mTOR/PI3K dual inhibitors effectively inhibited cell growth in all the lines, including those already resistant to BRAF inhibitors and ZSTK474. Conclusions Overall, this indicates a high degree of diversity in the way the PI3K pathway is activated in different melanoma cell lines and that mTOR is the most effective point for targeting the growth via the PI3K pathway across all of these cell lines. Supplementary Information The online version contains supplementary material available at 10.1186/s12885-021-07826-4.
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Affiliation(s)
- Khanh B Tran
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand.,Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
| | - Sharada Kolekar
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
| | - Anower Jabed
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Patrick Jaynes
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Jen-Hsing Shih
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Qian Wang
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Jack U Flanagan
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
| | - Gordon W Rewcastle
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
| | - Bruce C Baguley
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
| | - Peter R Shepherd
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand. .,Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand. .,Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand.
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5
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Baguley BC, Drummond CJ, Chen YY, Finlay GJ. DNA-Binding Anticancer Drugs: One Target, Two Actions. Molecules 2021; 26:molecules26030552. [PMID: 33494466 PMCID: PMC7866126 DOI: 10.3390/molecules26030552] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2020] [Revised: 01/11/2021] [Accepted: 01/15/2021] [Indexed: 11/30/2022] Open
Abstract
Amsacrine, an anticancer drug first synthesised in 1970 by Professor Cain and colleagues, showed excellent preclinical activity and underwent clinical trial in 1978 under the auspices of the US National Cancer Institute, showing activity against acute lymphoblastic leukaemia. In 1984, the enzyme DNA topoisomerase II was identified as a molecular target for amsacrine, acting to poison this enzyme and to induce DNA double-strand breaks. One of the main challenges in the 1980s was to determine whether amsacrine analogues could be developed with activity against solid tumours. A multidisciplinary team was assembled in Auckland, and Professor Denny played a leading role in this approach. Among a large number of drugs developed in the programme, N-[2-(dimethylamino)-ethyl]-acridine-4-carboxamide (DACA), first synthesised by Professor Denny, showed excellent activity against a mouse lung adenocarcinoma. It underwent clinical trial, but dose escalation was prevented by ion channel toxicity. Subsequent work led to the DACA derivative SN 28049, which had increased potency and reduced ion channel toxicity. Mode of action studies suggested that both amsacrine and DACA target the enzyme DNA topoisomerase II but with a different balance of cellular consequences. As primarily a topoisomerase II poison, amsacrine acts to turn the enzyme into a DNA-damaging agent. As primarily topoisomerase II catalytic inhibitors, DACA and SN 28049 act to inhibit the segregation of daughter chromatids during anaphase. The balance between these two actions, one cell cycle phase specific and the other nonspecific, together with pharmacokinetic, cytokinetic and immunogenic considerations, provides links between the actions of acridine derivatives and anthracyclines such as doxorubicin. They also provide insights into the action of cytotoxic DNA-binding drugs.
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6
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Tran KB, Gimenez G, Tsai P, Kolekar S, Rodger EJ, Chatterjee A, Jabed A, Shih JH, Joseph WR, Marshall ES, Wang Q, Print CG, Eccles MR, Baguley BC, Shepherd PR. Genomic and signalling pathway characterization of the NZM panel of melanoma cell lines: A valuable model for studying the impact of genetic diversity in melanoma. Pigment Cell Melanoma Res 2020; 34:136-143. [PMID: 32567790 PMCID: PMC7818249 DOI: 10.1111/pcmr.12908] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 06/07/2020] [Indexed: 12/14/2022]
Abstract
Melanoma is a disease associated with a very high mutation burden and thus the possibility of a diverse range of oncogenic mechanisms that allow it to evade therapeutic interventions and the immune system. Here, we describe the characterization of a panel of 102 cell lines from metastatic melanomas (the NZM lines), including using whole‐exome and RNA sequencing to analyse genetic variants and gene expression changes in a subset of this panel. Lines possessing all major melanoma genotypes were identified, and hierarchical clustering of gene expression profiles revealed four broad subgroups of cell lines. Immunogenotyping identified a range of HLA haplotypes as well as expression of neoantigens and cancer–testis antigens in the lines. Together, these characteristics make the NZM panel a valuable resource for cell‐based, immunological and xenograft studies to better understand the diversity of melanoma biology and the responses of melanoma to therapeutic interventions.
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Affiliation(s)
- Khanh B Tran
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
| | - Gregory Gimenez
- Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand.,Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Peter Tsai
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
| | - Sharada Kolekar
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand.,Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Euan J Rodger
- Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand.,Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Aniruddha Chatterjee
- Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand.,Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Anower Jabed
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
| | - Jen-Hsing Shih
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
| | - Wayne R Joseph
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Elaine S Marshall
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Qian Wang
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
| | - Cristin G Print
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
| | - Michael R Eccles
- Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand.,Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Bruce C Baguley
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Peter R Shepherd
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand.,Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
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7
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Singleton DC, Dechaume AL, Murray PM, Katt WP, Baguley BC, Leung EY. Pyruvate anaplerosis is a mechanism of resistance to pharmacological glutaminase inhibition in triple-receptor negative breast cancer. BMC Cancer 2020; 20:470. [PMID: 32450839 PMCID: PMC7333265 DOI: 10.1186/s12885-020-06885-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 04/21/2020] [Indexed: 12/31/2022] Open
Abstract
Background Glutamine serves as an important nutrient with many cancer types displaying glutamine dependence. Following cellular uptake glutamine is converted to glutamate in a reaction catalysed by mitochondrial glutaminase. This glutamate has many uses, including acting as an anaplerotic substrate (via alpha-ketoglutarate) to replenish TCA cycle intermediates. CB-839 is a potent, selective, orally bioavailable inhibitor of glutaminase that has activity in Triple receptor-Negative Breast Cancer (TNBC) cell lines and evidence of efficacy in advanced TNBC patients. Methods A panel of eleven breast cancer cell lines was used to investigate the anti-proliferative effects of the glutaminase inhibitors CB-839 and BPTES in different types of culture medium, with or without additional pyruvate supplementation. The abundance of the TCA cycle intermediate fumarate was quantified as a measure if TCA cycle anaplerosis. Pyruvate secretion by TNBC cultures was then assessed with or without AZD3965, a monocarboxylate transporter 1 (MCT1) inhibitor. Finally, two dimensional (2D) monolayer and three dimensional (3D) spheroid assays were used to compare the effect of microenvironmental growth conditions on CB-839 activity. Results The anti-proliferative activity of CB-839 in a panel of breast cancer cell lines was similar to published reports, but with a major caveat; growth inhibition by CB-839 was strongly attenuated in culture medium containing pyruvate. This pyruvate-dependent attenuation was also observed with a related glutaminase inhibitor, BPTES. Studies demonstrated that exogenous pyruvate acted as an anaplerotic substrate preventing the decrease of fumarate in CB-839-treated conditions. Furthermore, endogenously produced pyruvate secreted by TNBC cell lines was able to act in a paracrine manner to significantly decrease the sensitivity of recipient cells to glutaminase inhibition. Suppression of pyruvate secretion using the MCT1 inhibitor AZD3965, antagonised this paracrine effect and increased CB-839 activity. Finally, CB-839 activity was significantly compromised in 3D compared with 2D TNBC culture models, suggesting that 3D microenvironmental features impair glutaminase inhibitor responsiveness. Conclusion This study highlights the potential influence that both circulating and tumour-derived pyruvate can have on glutaminase inhibitor efficacy. Furthermore, it highlights the benefits of 3D spheroid cultures to model the features of the tumour microenvironment and improve the in vitro investigation of cancer metabolism-targeted therapeutics.
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Affiliation(s)
- Dean C Singleton
- Auckland Cancer Society Research Centre, School of Medical Sciences, Faculty of Medical and Health Sciences University of Auckland, Private Bag, Auckland, 92019, New Zealand. .,Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Symonds Street, Auckland, 1010, New Zealand.
| | - Anne-Lise Dechaume
- Auckland Cancer Society Research Centre, School of Medical Sciences, Faculty of Medical and Health Sciences University of Auckland, Private Bag, Auckland, 92019, New Zealand
| | - Pamela M Murray
- Auckland Cancer Society Research Centre, School of Medical Sciences, Faculty of Medical and Health Sciences University of Auckland, Private Bag, Auckland, 92019, New Zealand
| | - William P Katt
- Department of Molecular Medicine, Cornell University, Ithaca, New York, 14853, USA
| | - Bruce C Baguley
- Auckland Cancer Society Research Centre, School of Medical Sciences, Faculty of Medical and Health Sciences University of Auckland, Private Bag, Auckland, 92019, New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Symonds Street, Auckland, 1010, New Zealand
| | - Euphemia Y Leung
- Auckland Cancer Society Research Centre, School of Medical Sciences, Faculty of Medical and Health Sciences University of Auckland, Private Bag, Auckland, 92019, New Zealand. .,Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Symonds Street, Auckland, 1010, New Zealand.
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8
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Leung EY, Askarian-Amiri ME, Singleton DC, Ferraro-Peyret C, Joseph WR, Finlay GJ, Broom RJ, Kakadia PM, Bohlander SK, Marshall E, Baguley BC. Derivation of Breast Cancer Cell Lines Under Physiological (5%) Oxygen Concentrations. Front Oncol 2018; 8:425. [PMID: 30370249 PMCID: PMC6194255 DOI: 10.3389/fonc.2018.00425] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Accepted: 09/11/2018] [Indexed: 11/13/2022] Open
Abstract
Background: Most human breast cancer cell lines currently in use were developed and are cultured under ambient (21%) oxygen conditions. While this is convenient in practical terms, higher ambient oxygen could increase oxygen radical production, potentially modulating signaling pathways. We have derived and grown a series of four human breast cancer cell lines under 5% oxygen, and have compared their properties to those of established breast cancer lines growing under ambient oxygen. Methods: Cell lines were characterized in terms of appearance, cellular DNA content, mutation spectrum, hormone receptor status, pathway utilization and drug sensitivity. Results: Three of the four lines (NZBR1, NZBR2, and NZBR4) were triple negative (ER-, PR-, HER2-), with NZBR1 also over-expressing EGFR. NZBR3 was HER2+ and ER+ and also over-expressed EGFR. Cell lines grown in 5% oxygen showed increased expression of the hypoxia-inducible factor 1 (HIF-1) target gene carbonic anhydrase 9 (CA9) and decreased levels of ROS. As determined by protein phosphorylation, NZBR1 showed low AKT pathway utilization while NZBR2 and NZBR4 showed low p70S6K and rpS6 pathway utilization. The lines were characterized for sensitivity to 7-hydroxytamoxifen, doxorubicin, paclitaxel, the PI3K inhibitor BEZ235 and the HER inhibitors lapatinib, afatinib, dacomitinib, and ARRY-380. In some cases they were compared to established breast cancer lines. Of particular note was the high sensitivity of NZBR3 to HER inhibitors. The spectrum of mutations in the NZBR lines was generally similar to that found in commonly used breast cancer cell lines but TP53 mutations were absent and mutations in EVI2B, LRP1B, and PMS2, which have not been reported in other breast cancer lines, were detected. The results suggest that the properties of cell lines developed under low oxygen conditions (5% O2) are similar to those of commonly used breast cancer cell lines. Although reduced ROS production and increased HIF-1 activity under 5% oxygen can potentially influence experimental outcomes, no difference in sensitivity to estrogen or doxorubicin was observed between cell lines cultured in 5 vs. 21% oxygen.
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Affiliation(s)
- Euphemia Y Leung
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand.,Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
| | - Marjan E Askarian-Amiri
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand.,Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
| | - Dean C Singleton
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Carole Ferraro-Peyret
- Univ Lyon, Claude Bernard University, Cancer Research Center of Lyon, INSERM 1052, CNRS5286, Faculty of Pharmacy, Lyon, France.,Hospices Civils de Lyon, Molecular Biology of Tumors, GHE Hospital, Bron, France
| | - Wayne R Joseph
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Graeme J Finlay
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand.,Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
| | - Reuben J Broom
- Auckland City Hospital-Oncology, Grafton, Auckland, New Zealand
| | - Purvi M Kakadia
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
| | - Stefan K Bohlander
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
| | - Elaine Marshall
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Bruce C Baguley
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
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9
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Zhang W, Li C, Jin Y, Liu X, Wang Z, Shaw JP, Baguley BC, Wu Z, Liu J. Multiseed liposomal drug delivery system using micelle gradient as driving force to improve amphiphilic drug retention and its anti-tumor efficacy. Drug Deliv 2018; 25:611-622. [PMID: 29493300 PMCID: PMC6058678 DOI: 10.1080/10717544.2018.1440669] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
To improve drug retention in carriers for amphiphilic asulacrine (ASL), a novel active loading method using micelle gradient was developed to fabricate the ASL-loaded multiseed liposomes (ASL-ML). The empty ML were prepared by hydrating a thin film with empty micelles. Then the micelles in liposomal compartment acting as ‘micelle pool’ drove the drug to be loaded after the outer micelles were removed. Some reasoning studies including critical micelle concentration (CMC) determination, influencing factors tests on entrapment efficiency (EE), structure visualization, and drug release were carried out to explore the mechanism of active loading, ASL location, and the structure of ASL-ML. Comparisons were made between pre-loading and active loading method. Finally, the extended drug retention capacity of ML was evaluated through pharmacokinetic, drug tissue irritancy, and in vivo anti-tumor activity studies. Comprehensive results from fluorescent and transmission electron microscope (TEM) observation, encapsulation efficiency (EE) comparison, and release studies demonstrated the formation of ML-shell structure for ASL-ML without inter-carrier fusion. The location of drug mainly in inner micelles as well as the superiority of post-loading to the pre-loading method , in which drug in micelles shifted onto the bilayer membrane was an additional positive of this delivery system. It was observed that the drug amphiphilicity and interaction of micelles with drug were the two prerequisites for this active loading method. The extended retention capacity of ML has been verified through the prolonged half-life, reduced paw-lick responses in rats, and enhanced tumor inhibition in model mice. In conclusion, ASL-ML prepared by active loading method can effectively load drug into micelles with expected structure and improve drug retention.
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Affiliation(s)
- Wenli Zhang
- a Department of Pharmaceutics , China Pharmaceutical University , Nanjing , PR China
| | - Caibin Li
- a Department of Pharmaceutics , China Pharmaceutical University , Nanjing , PR China
| | - Ya Jin
- a Department of Pharmaceutics , China Pharmaceutical University , Nanjing , PR China
| | - Xinyue Liu
- a Department of Pharmaceutics , China Pharmaceutical University , Nanjing , PR China
| | - Zhiyu Wang
- a Department of Pharmaceutics , China Pharmaceutical University , Nanjing , PR China
| | - John P Shaw
- b School of Pharmacy , University of Auckland , Auckland , New Zealand
| | - Bruce C Baguley
- c Auckland Cancer Society Cancer Research Centre , University of Auckland , Auckland , New Zealand
| | - Zimei Wu
- b School of Pharmacy , University of Auckland , Auckland , New Zealand
| | - Jianping Liu
- a Department of Pharmaceutics , China Pharmaceutical University , Nanjing , PR China
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10
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Sarkar D, Oghabian A, Bodiyabadu PK, Joseph WR, Leung EY, Finlay GJ, Baguley BC, Askarian-Amiri ME. Correction: Sarkar, D., et al. Multiple Isoforms of ANRIL in Melanoma Cells: Structural Complexity Suggests Variations in Processing. Int. J. Mol. Sci. 2017, 18, 1378. Int J Mol Sci 2018; 19:ijms19051343. [PMID: 29724053 PMCID: PMC5983800 DOI: 10.3390/ijms19051343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 04/11/2018] [Accepted: 04/12/2018] [Indexed: 11/17/2022] Open
Affiliation(s)
- Debina Sarkar
- Auckland Cancer Society Research Centre, University of Auckland, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
| | - Ali Oghabian
- Institute of Biotechnology, P.O. Box 56 (Viikinkaari 5), University of Helsinki, FI-00014 Helsinki, Finland.
| | - Pasani K Bodiyabadu
- Auckland Cancer Society Research Centre, University of Auckland, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
| | - Wayne R Joseph
- Auckland Cancer Society Research Centre, University of Auckland, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
| | - Euphemia Y Leung
- Auckland Cancer Society Research Centre, University of Auckland, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
| | - Graeme J Finlay
- Auckland Cancer Society Research Centre, University of Auckland, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
| | - Bruce C Baguley
- Auckland Cancer Society Research Centre, University of Auckland, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
| | - Marjan E Askarian-Amiri
- Auckland Cancer Society Research Centre, University of Auckland, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
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11
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Leung EY, Askarian-Amiri ME, Sarkar D, Ferraro-Peyret C, Joseph WR, Finlay GJ, Baguley BC. Endocrine Therapy of Estrogen Receptor-Positive Breast Cancer Cells: Early Differential Effects on Stem Cell Markers. Front Oncol 2017; 7:184. [PMID: 28929082 PMCID: PMC5591432 DOI: 10.3389/fonc.2017.00184] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Accepted: 08/08/2017] [Indexed: 01/13/2023] Open
Abstract
Introduction Endocrine therapy of breast cancer, which either deprives cancer tissue of estrogen or prevents estrogen pathway signaling, is the most common treatment after surgery and radiotherapy. We have previously shown for the estrogen-responsive MCF-7 cell line that exposure to tamoxifen, or deprivation of estrogen, leads initially to inhibition of cell proliferation, followed after several months by the emergence of resistant sub-lines that are phenotypically different from the parental line. We examined the early responses of MCF-7 cells following either exposure to 4-hydroxytamoxifen or deprivation of estrogen for periods of 2 days–4 weeks. Methods Endocrine-sensitive or -resistant breast cancer cell lines were used to examine the expression of the stem cell gene SOX2, and the Wnt effector genes AXIN2 and DKK1 using quantitative PCR analysis. Breast cancer cell lines were used to assess the anti-proliferative effects (as determined by IC50 values) of Wnt pathway inhibitors LGK974 and IWP-2. Results Hormone therapy led to time-dependent increases of up to 10-fold in SOX2 expression, up to threefold in expression of the Wnt target genes AXIN2 and DKK1, and variable changes in NANOG and OCT4 expression. The cells also showed increased mammosphere formation and increased CD24 surface protein expression. Some but not all hormone-resistant MCF-7 sub-lines, emerging after long-term hormonal stress, showed up to 50-fold increases in SOX2 expression and smaller increases in AXIN2 and DKK1 expression. However, the increase in Wnt target gene expression was not accompanied by an increase in sensitivity to Wnt pathway inhibitors LGK974 and IWP-2. A general trend of lower IC50 values was observed in 3-dimensional spheroid culture conditions (which allowed enrichment of cells with cancer stem cell phenotype) relative to monolayer cultures. The endocrine-resistant cell lines showed no significant increase in sensitivity to Wnt inhibitors. Conclusion Hormone treatment of cultured MCF-7 cells leads within 2 days to increased expression of components of the SOX2 and Wnt pathways and to increased potential for mammosphere formation. We suggest that these responses are indicative of early adaptation to endocrine stress with features of stem cell character and that this facilitates the survival of emerging hormone-resistant cell populations.
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Affiliation(s)
- Euphemia Y Leung
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand.,Molecular Medicine and Pathology Department, University of Auckland, Auckland, New Zealand
| | - Marjan E Askarian-Amiri
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand.,Molecular Medicine and Pathology Department, University of Auckland, Auckland, New Zealand
| | - Debina Sarkar
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand.,Molecular Medicine and Pathology Department, University of Auckland, Auckland, New Zealand
| | - Carole Ferraro-Peyret
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand.,Cancer Research Center of Lyon, INSERM 1052, CNRS5286, Lyon, France.,Faculty of Pharmacy, University of Lyon, Claude Bernard Lyon 1 University, Lyon, France.,Molecular Biology of Tumors, Hôpital Edouard Herriot, Hospices Civils de Lyon, Lyon, France
| | - Wayne R Joseph
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Graeme J Finlay
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand.,Molecular Medicine and Pathology Department, University of Auckland, Auckland, New Zealand
| | - Bruce C Baguley
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
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12
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Sarkar D, Oghabian A, Bodiyabadu PK, Joseph WR, Leung EY, Finlay GJ, Baguley BC, Askarian-Amiri ME. Multiple Isoforms of ANRIL in Melanoma Cells: Structural Complexity Suggests Variations in Processing. Int J Mol Sci 2017; 18:ijms18071378. [PMID: 28653984 PMCID: PMC5535871 DOI: 10.3390/ijms18071378] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2017] [Revised: 06/21/2017] [Accepted: 06/22/2017] [Indexed: 11/29/2022] Open
Abstract
The long non-coding RNA ANRIL, antisense to the CDKN2B locus, is transcribed from a gene that encompasses multiple disease-associated polymorphisms. Despite the identification of multiple isoforms of ANRIL, expression of certain transcripts has been found to be tissue-specific and the characterisation of ANRIL transcripts remains incomplete. Several functions have been associated with ANRIL. In our judgement, studies on ANRIL functionality are premature pending a more complete appreciation of the profusion of isoforms. We found differential expression of ANRIL exons, which indicates that multiple isoforms exist in melanoma cells. In addition to linear isoforms, we identified circular forms of ANRIL (circANRIL). Further characterisation of circANRIL in two patient-derived metastatic melanoma cell lines (NZM7 and NZM37) revealed the existence of a rich assortment of circular isoforms. Moreover, in the two melanoma cell lines investigated, the complements of circANRIL isoforms were almost completely different. Novel exons were also discovered. We also found the family of linear ANRIL was enriched in the nucleus, whilst the circular isoforms were enriched in the cytoplasm and they differed markedly in stability. With respect to the variable processing of circANRIL species, bioinformatic analysis indicated that intronic Arthrobacter luteus (Alu) restriction endonuclease inverted repeats and exon skipping were not involved in selection of back-spliced exon junctions. Based on our findings, we hypothesise that “ANRIL” has wholly distinct dual sets of functions in melanoma. This reveals the dynamic nature of the locus and constitutes a basis for investigating the functions of ANRIL in melanoma.
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Affiliation(s)
- Debina Sarkar
- Auckland Cancer Society Research Centre, University of Auckland, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
| | - Ali Oghabian
- Institute of Biotechnology, P.O. Box 56 (Viikinkaari 5), University of Helsinki, FI-00014 Helsinki, Finland.
| | - Pasani K Bodiyabadu
- Auckland Cancer Society Research Centre, University of Auckland, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
| | - Wayne R Joseph
- Auckland Cancer Society Research Centre, University of Auckland, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
| | - Euphemia Y Leung
- Auckland Cancer Society Research Centre, University of Auckland, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
| | - Graeme J Finlay
- Auckland Cancer Society Research Centre, University of Auckland, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
| | - Bruce C Baguley
- Auckland Cancer Society Research Centre, University of Auckland, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
| | - Marjan E Askarian-Amiri
- Auckland Cancer Society Research Centre, University of Auckland, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd. Grafton, 1023 Auckland, New Zealand.
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13
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Silva JM, Deuker MM, Baguley BC, McMahon M. PIK3CA-mutated melanoma cells rely on cooperative signaling through mTORC1/2 for sustained proliferation. Pigment Cell Melanoma Res 2017; 30:353-367. [PMID: 28233937 DOI: 10.1111/pcmr.12586] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Accepted: 02/20/2017] [Indexed: 01/01/2023]
Abstract
Malignant conversion of BRAF- or NRAS-mutated melanocytes into melanoma cells can be promoted by PI3'-lipid signaling. However, the mechanism by which PI3'-lipid signaling cooperates with mutationally activated BRAF or NRAS has not been adequately explored. Using human NRAS- or BRAF-mutated melanoma cells that co-express mutationally activated PIK3CA, we explored the contribution of PI3'-lipid signaling to cell proliferation. Despite mutational activation of PIK3CA, melanoma cells were more sensitive to the biochemical and antiproliferative effects of broader spectrum PI3K inhibitors than to an α-selective PI3K inhibitor. Combined pharmacological inhibition of MEK1/2 and PI3K signaling elicited more potent antiproliferative effects and greater inhibition of the cell division cycle compared to single-agent inhibition of either pathway alone. Analysis of signaling downstream of MEK1/2 or PI3K revealed that these pathways cooperate to regulate cell proliferation through mTORC1-mediated effects on ribosomal protein S6 and 4E-BP1 phosphorylation in an AKT-dependent manner. Although PI3K inhibition resulted in cytostatic effects on xenografted NRASQ61H /PIK3CAH1047R melanoma, combined inhibition of MEK1/2 plus PI3K elicited significant melanoma regression. This study provides insights as to how mutationally activated PIK3CA acts in concert with MEK1/2 signaling to cooperatively regulate mTORC1/2 to sustain PIK3CA-mutated melanoma proliferation.
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Affiliation(s)
- Jillian M Silva
- Helen Diller Family Comprehensive Cancer Center, Department of Cellular & Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA
| | - Marian M Deuker
- Helen Diller Family Comprehensive Cancer Center, Department of Cellular & Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA
| | - Bruce C Baguley
- Auckland Cancer Society Research Centre, School of Medical Sciences, University of Auckland, Auckland, New Zealand
| | - Martin McMahon
- Helen Diller Family Comprehensive Cancer Center, Department of Cellular & Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA
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14
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Kendall JD, Giddens AC, Tsang KY, Marshall ES, Lill CL, Lee WJ, Kolekar S, Chao M, Malik A, Yu S, Chaussade C, Buchanan C, Jamieson SM, Rewcastle GW, Baguley BC, Denny WA, Shepherd PR. Novel pyrazolo[1,5- a ]pyridines with improved aqueous solubility as p110α-selective PI3 kinase inhibitors. Bioorg Med Chem Lett 2017; 27:187-190. [DOI: 10.1016/j.bmcl.2016.11.078] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 11/23/2016] [Accepted: 11/24/2016] [Indexed: 10/20/2022]
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15
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Hansji H, Leung EY, Baguley BC, Finlay GJ, Cameron-Smith D, Figueiredo VC, Askarian-Amiri ME. ZFAS1: a long noncoding RNA associated with ribosomes in breast cancer cells. Biol Direct 2016; 11:62. [PMID: 27871336 PMCID: PMC5117590 DOI: 10.1186/s13062-016-0165-y] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 11/11/2016] [Indexed: 12/20/2022] Open
Abstract
Background Most of the eukaryotic genome is transcribed, yielding a complex network of transcripts including thousands of lncRNAs that generally lack protein coding potential. However, only a small percentage of these molecules has been functionally characterised, and discoveries of specific functions demonstrate layers of complexity. A large percentage of lncRNAs is located in the cytoplasm, associated with ribosomes but the function of the majority of these transcripts is unclear. The current study analyses putative mechanisms of action of the lncRNA species member ZFAS1 that was initially discovered by microarray analysis of murine tissues undergoing mammary gland development. As developmental genes are often deregulated in cancer, here we have studied its function in breast cancer cell lines. Results Using human breast cancer cell lines, ZFAS1 was found to be expressed in all cell lines tested, albeit at different levels of abundance. Following subcellular fractionation, human ZFAS1 was found in both nucleus and cytoplasm (as is the mouse orthologue) in an isoform-independent manner. Sucrose gradients based on velocity sedimentation were utilised to separate the different components of total cell lysate, and surprisingly ZFAS1 was primarily co-localised with light polysomes. Further investigation into ribosome association through subunit dissociation studies showed that ZFAS1 was predominantly associated with the 40S small ribosomal subunit. The expression levels of ZFAS1 and of mRNAs encoding several ribosomal proteins that have roles in ribosome assembly, production and maturation were tightly correlated. ZFAS1 knockdown significantly reduced RPS6 phosphorylation. Conclusion A large number of lncRNAs associate with ribosomes but the function of the majority of these lncRNAs has not been elucidated. The association of the lncRNA ZFAS1 with a subpopulation of ribosomes and the correlation with expression of mRNAs for ribosomal proteins suggest a ribosome-interacting mechanism pertaining to their assembly or biosynthetic activity. ZFAS1 may represent a new class of lncRNAs which associates with ribosomes to regulate their function. Reviewers This article was reviewed by Christine Vande Velde, Nicola Aceto and Haruhiko Siomi. Electronic supplementary material The online version of this article (doi:10.1186/s13062-016-0165-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Herah Hansji
- Auckland Cancer Society Research Centre, University of Auckland, 85 Park Rd, Grafton, Auckland, 1023, New Zealand.,Department of Molecular Medicine and Pathology, University of Auckland, 85 Park Rd, Grafton, Auckland, 1023, New Zealand
| | - Euphemia Y Leung
- Auckland Cancer Society Research Centre, University of Auckland, 85 Park Rd, Grafton, Auckland, 1023, New Zealand.,Department of Molecular Medicine and Pathology, University of Auckland, 85 Park Rd, Grafton, Auckland, 1023, New Zealand
| | - Bruce C Baguley
- Auckland Cancer Society Research Centre, University of Auckland, 85 Park Rd, Grafton, Auckland, 1023, New Zealand
| | - Graeme J Finlay
- Auckland Cancer Society Research Centre, University of Auckland, 85 Park Rd, Grafton, Auckland, 1023, New Zealand.,Department of Molecular Medicine and Pathology, University of Auckland, 85 Park Rd, Grafton, Auckland, 1023, New Zealand
| | - David Cameron-Smith
- The Liggins Institute, University of Auckland, 85 Park Rd, Grafton, Auckland, 1023, New Zealand
| | - Vandre C Figueiredo
- The Liggins Institute, University of Auckland, 85 Park Rd, Grafton, Auckland, 1023, New Zealand
| | - Marjan E Askarian-Amiri
- Auckland Cancer Society Research Centre, University of Auckland, 85 Park Rd, Grafton, Auckland, 1023, New Zealand. .,Department of Molecular Medicine and Pathology, University of Auckland, 85 Park Rd, Grafton, Auckland, 1023, New Zealand.
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16
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Zhang W, Li C, Baguley BC, Zhou F, Zhou W, Shaw JP, Wang Z, Wu Z, Liu J. Optimization of the formation of embedded multicellular spheroids of MCF-7 cells: How to reliably produce a biomimetic 3D model. Anal Biochem 2016; 515:47-54. [PMID: 27717854 DOI: 10.1016/j.ab.2016.10.004] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 09/13/2016] [Accepted: 10/03/2016] [Indexed: 01/09/2023]
Abstract
To obtain a multicellular MCF-7 spheroid model to mimic the three-dimensional (3D) of tumors, the microwell liquid overlay (A) and hanging-drop/agar (B) methods were first compared for their technical parameters. Then a method for embedding spheroids within collagen was optimized. For method A, centrifugation assisted cells form irregular aggregates but not spheroids. For method B, an extended sedimentation period of over 24 h for cell suspensions and increased viscosity of the culture medium using methylcellulose were necessary to harvest a dense and regular cell spheroid. When the number was less than 5000 cells/drop, embedded spheroids showed no tight cores and higher viability than the unembedded. However, above 5000 cells/drop, cellular viability of embedded spheroids was not significantly different from unembedded spheroids and cells invading through the collagen were in a sun-burst pattern with tight cores. Propidium Iodide staining indicated that spheroids had necrotic cores. The doxorubicin cytotoxicity demonstrated that spheroids were less susceptible to DOX than their monolayer cells. A reliable and reproducible method for embedding spheroids using the hanging-drop/agarose method within collagen is described herein. The cell culture model can be used to guide experimental manipulation of 3D cell cultures and to evaluate anticancer drug efficacy.
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Affiliation(s)
- Wenli Zhang
- Department of Pharmaceutics, China Pharmaceutical University, Nanjing, 210009, PR China
| | - Caibin Li
- Department of Pharmaceutics, China Pharmaceutical University, Nanjing, 210009, PR China
| | - Bruce C Baguley
- Auckland Cancer Society Research Centre, University of Auckland, Private Bag 92019, Auckland, New Zealand
| | - Fang Zhou
- Key Laboratory of Drug Metabolism and Pharmacokinetics, China Pharmaceutical University, Nanjing, 210009, PR China
| | - Weisai Zhou
- Department of Pharmaceutics, China Pharmaceutical University, Nanjing, 210009, PR China
| | - John P Shaw
- School of Pharmacy, University of Auckland, Private Bag 92019, Auckland, New Zealand
| | - Zhen Wang
- Department of Pharmaceutics, China Pharmaceutical University, Nanjing, 210009, PR China
| | - Zimei Wu
- School of Pharmacy, University of Auckland, Private Bag 92019, Auckland, New Zealand.
| | - Jianping Liu
- Department of Pharmaceutics, China Pharmaceutical University, Nanjing, 210009, PR China.
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17
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D'mello SAN, Joseph WR, Green TN, Leung EY, During MJ, Finlay GJ, Baguley BC, Kalev-Zylinska ML. Selected GRIN2A mutations in melanoma cause oncogenic effects that can be modulated by extracellular glutamate. Cell Calcium 2016; 60:384-395. [PMID: 27659111 DOI: 10.1016/j.ceca.2016.09.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 08/29/2016] [Accepted: 09/13/2016] [Indexed: 02/09/2023]
Abstract
GRIN2A mutations are frequent in melanoma tumours but their role in disease is not well understood. GRIN2A encodes a modulatory subunit of the N-methyl-d-aspartate receptor (NMDAR). We hypothesized that certain GRIN2A mutations increase NMDAR function and support melanoma growth through oncogenic effects. This hypothesis was tested using 19 low-passage melanoma cell lines, four of which carried novel missense mutations in GRIN2A that we previously reported. We examined NMDAR expression, function of a calcium ion (Ca2+) channel and its contribution to cell growth using pharmacological modulators; findings were correlated with the presence or absence of GRIN2A mutations. We found that NMDAR expression was low in all melanoma cell lines, independent of GRIN2A mutations. In keeping with this, NMDAR-mediated Ca2+ influx and its contribution to cell proliferation were weak in most cell lines. However, certain GRIN2A mutations and culture media with lower glutamate levels enhanced NMDAR effects on cell growth and invasion. The main finding was that G762E was associated with higher glutamate-mediated Ca2+ influx and stronger NMDAR contribution to cell proliferation, compared with wild-type GRIN2A and other GRIN2A mutations. The pro-invasive phenotype of mutated cell lines was increased in culture medium containing less glutamate, implying environmental modulation of mutation effects. In conclusion, NMDAR ion channel function is low in cultured melanoma cells but supports cell proliferation and invasion. Selected GRIN2A mutations, such as G762E, are associated with oncogenic consequences that can be modulated by extracellular glutamate. Primary cultures may be better suited to determine the role of the NMDAR in melanoma in vivo.
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Affiliation(s)
- Stacey Ann N D'mello
- Department of Molecular Medicine and Pathology, University of Auckland, Private Bag 92019, Auckland, New Zealand; Auckland Cancer Society Research Centre, University of Auckland, Auckland, Private Bag 92019, Auckland, New Zealand
| | - Wayne R Joseph
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, Private Bag 92019, Auckland, New Zealand
| | - Taryn N Green
- Department of Molecular Medicine and Pathology, University of Auckland, Private Bag 92019, Auckland, New Zealand
| | - Euphemia Y Leung
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, Private Bag 92019, Auckland, New Zealand
| | - Matthew J During
- Cancer Genetics and Neuroscience Program, Department of Molecular Virology, Immunology and Medical Genetics, The Ohio State University, Columbus, OH 43210, United States
| | - Graeme J Finlay
- Department of Molecular Medicine and Pathology, University of Auckland, Private Bag 92019, Auckland, New Zealand; Auckland Cancer Society Research Centre, University of Auckland, Auckland, Private Bag 92019, Auckland, New Zealand
| | - Bruce C Baguley
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, Private Bag 92019, Auckland, New Zealand
| | - Maggie L Kalev-Zylinska
- Department of Molecular Medicine and Pathology, University of Auckland, Private Bag 92019, Auckland, New Zealand; LabPlus Haematology, Auckland City Hospital, Private Bag 92024, Auckland, New Zealand.
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18
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Portier CJ, Armstrong BK, Baguley BC, Baur X, Belyaev I, Bellé R, Belpoggi F, Biggeri A, Bosland MC, Bruzzi P, Budnik LT, Bugge MD, Burns K, Calaf GM, Carpenter DO, Carpenter HM, López-Carrillo L, Clapp R, Cocco P, Consonni D, Comba P, Craft E, Dalvie MA, Davis D, Demers PA, De Roos AJ, DeWitt J, Forastiere F, Freedman JH, Fritschi L, Gaus C, Gohlke JM, Goldberg M, Greiser E, Hansen J, Hardell L, Hauptmann M, Huang W, Huff J, James MO, Jameson CW, Kortenkamp A, Kopp-Schneider A, Kromhout H, Larramendy ML, Landrigan PJ, Lash LH, Leszczynski D, Lynch CF, Magnani C, Mandrioli D, Martin FL, Merler E, Michelozzi P, Miligi L, Miller AB, Mirabelli D, Mirer FE, Naidoo S, Perry MJ, Petronio MG, Pirastu R, Portier RJ, Ramos KS, Robertson LW, Rodriguez T, Röösli M, Ross MK, Roy D, Rusyn I, Saldiva P, Sass J, Savolainen K, Scheepers PTJ, Sergi C, Silbergeld EK, Smith MT, Stewart BW, Sutton P, Tateo F, Terracini B, Thielmann HW, Thomas DB, Vainio H, Vena JE, Vineis P, Weiderpass E, Weisenburger DD, Woodruff TJ, Yorifuji T, Yu IJ, Zambon P, Zeeb H, Zhou SF. Differences in the carcinogenic evaluation of glyphosate between the International Agency for Research on Cancer (IARC) and the European Food Safety Authority (EFSA). J Epidemiol Community Health 2016; 70:741-5. [PMID: 26941213 PMCID: PMC4975799 DOI: 10.1136/jech-2015-207005] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
| | | | | | - Xaver Baur
- Charité University Medicine Berlin, Berlin, Germany
| | - Igor Belyaev
- Cancer Research Institute, Bratislava, Slovak Republic
| | - Robert Bellé
- Sorbonne Universités, UPMC Univ Paris 06, UMR8227, Roscoff, France
| | | | - Annibale Biggeri
- Institute for Cancer Prevention and Research, University of Florence, Italy
| | | | - Paolo Bruzzi
- National Cancer Research Institute, San Martino—IST Hospital, Genoa, Italy
| | | | - Merete D Bugge
- STAMI, National Institute of Occupational Health, Oslo, Norway
| | | | - Gloria M Calaf
- Instituto de Alta Investigación, Universidad de Tarapacá, Arica, Chile
| | - David O Carpenter
- Institute for Health and the Environment, University at Albany, Rensselaer, New York, USA
| | | | | | - Richard Clapp
- Boston University School of Public Health, Boston, Massachusetts, USA
| | - Pierluigi Cocco
- Department of Public Health, Clinical and Molecular Medicine, University of Cagliari, Cagliari, Italy
| | - Dario Consonni
- Department of Preventive Medicine, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Pietro Comba
- Department of Environment and Primary Prevention, IstitutoSuperiore di Sanità, Rome, Italy
| | - Elena Craft
- Environmental Defense Fund, Austin, Texas, USA
| | - Mohamed Aqiel Dalvie
- Center for Environmental and Occupational Health, University of Cape Town, Cape Town, South Africa
| | - Devra Davis
- Environmental Health Trust, Jackson Hole, Wyoming, USA and The Hebrew University Hadassah School of Medicine, Jerusalem, Israel.
| | - Paul A Demers
- Dalla Lana School of Public Health, University of Toronto, Canada
| | - Anneclaire J De Roos
- Department of Environmental and Occupational Health, Drexel University, Philadelphia, Pennsylvania, USA
| | - Jamie DeWitt
- Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | | | | | - Lin Fritschi
- School of Public Health, Curtin University, Perth, Western Australia, Australia
| | - Caroline Gaus
- Department of Environmental Toxicology, The University of Queensland, Brisbane, Australia
| | - Julia M Gohlke
- Department of Population Health Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | | | | | - Johnni Hansen
- Danish Cancer Society Research Center, Copenhagen, Denmark
| | | | - Michael Hauptmann
- Biostatistics Branch, Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Wei Huang
- Faculty of Department of Occupational and Environmental Health, Peking Univ School of Public Health, Beijing, China
| | - James Huff
- National Institute for Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | | | - C W Jameson
- CWJ Consulting, LLC, Cape Coral, Florida, USA
| | - Andreas Kortenkamp
- Institute of Environment, Health and Societies, Brunel University London, London, UK
| | | | - Hans Kromhout
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands
| | - Marcelo L Larramendy
- National Council of Scientific and Technological Research, National University of La Plata, Argentina
| | - Philip J Landrigan
- Arnhold Institute for Global Health, Icahn School of Medicine at Mount Sinai,New York, USA
| | - Lawrence H Lash
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | | | - Charles F Lynch
- Department of Epidemiology, University of Iowa, Iowa City, Iowa, USA
| | - Corrado Magnani
- Cancer Epidemiology Unit, University of Eastern Piedmont, Novara, Italy
| | | | | | - Enzo Merler
- Department of Prevention, Occupational Health Unit, National Health Service, Padua, Italy
| | | | - Lucia Miligi
- Occupational and Environmental Epidemiology Unit, ISPO-Cancer Prevention and Research Institute, Florence, Italy
| | - Anthony B Miller
- Dalla Lana School of Public Health, University of Toronto, Canada
| | - Dario Mirabelli
- Unit of Cancer Epidemiology, University of Turin and CPO-Piemonte, Torino, Italy
| | - Franklin E Mirer
- Department of Environmental and Occupational Health Sciences, City University of New York School of Public Health, USA
| | - Saloshni Naidoo
- School of Nursing and Public Health, University of KwaZulu-Natal, Durban, South Africa
| | - Melissa J Perry
- Department of Environmental and Occupational Health, Milken Institute School of Public Health, The George Washington University, Washington DC, USA
| | - Maria Grazia Petronio
- Health and Environment-Department of Prevention, Local Health Authority-Empoli, Florence, Italy
| | - Roberta Pirastu
- Department of Biology and Biotechnology “Charles Darwin”, Sapienza Rome University, Italy
| | - Ralph J Portier
- Department of Environmental Sciences, School of the Coast & Environment, Louisiana State University, Baton Rouge, Los Angeles, USA
| | - Kenneth S Ramos
- Center for Applied Genetics and Genomic Medicine, University of Arizona Health Sciences, Tucson, Arizona, USA
| | - Larry W Robertson
- Iowa Superfund Research Program and the Interdisciplinary Graduate Program in Human Toxicology, University of Iowa, Iowa City, Iowa, USA
| | - Theresa Rodriguez
- Center for Research in Health, Work and Environment (CISTA), National Autonomous University of Nicaragua (UNAN-León), León, Nicaragua
| | - Martin Röösli
- Swiss Tropical and Public Health Institute, Associated Institute of the University of Basel, Basel, Switzerland
| | - Matt K Ross
- College of Veterinary Medicine, Mississippi State University, Mississippi State, USA
| | - Deodutta Roy
- Department of Environmental and Occupational Health, Florida International University, Miami, Florida, USA
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas, USA
| | - Paulo Saldiva
- Faculty of Medicine, University of São Paulo, São Paulo, Brazil
| | - Jennifer Sass
- Natural Resources Defense Council and George Washington University, Washington DC, USA
| | - Kai Savolainen
- Nanosafety Research Centre, Finnish Institute of Occupational Health, Helsinki, Finland
| | - Paul T J Scheepers
- Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Consolato Sergi
- Department of Pathology, University of Alberta, Edmonton, Alberta, Canada
| | - Ellen K Silbergeld
- Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Martyn T Smith
- School of Public Health, University of California, Berkeley, California, USA
| | - Bernard W Stewart
- Faculty of Medicine, University of New South Wales, Randwick, New South WalesAustralia
| | - Patrice Sutton
- Program on Reproductive Health and the Environment, University of California, San Francisco, California, USA
| | - Fabio Tateo
- Istituto di Geosceinze e Georisorse (CNR), Padova, Italy
| | | | - Heinz W Thielmann
- German Cancer Research Center, Heidelberg and Faculty of Pharmacy, Heidelberg University, Germany
| | - David B Thomas
- Fred Hutchinson Cancer Research Center, University of Washington, Seattle, Washington, USA
| | - Harri Vainio
- Faculty of Public Health, Kuwait University, Kuwait City, Kuwait
| | - John E Vena
- Department of Public Health Sciences, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Paolo Vineis
- Department of Environmental Epidemiology, Imperial College London, London, UK
| | - Elisabete Weiderpass
- Department of Research, Cancer Registry of Norway, Institute of Population-Based Cancer Research, Oslo, Norway; Department of Community Medicine, Faculty of Health Sciences, University of Tromsø, The Arctic University of Norway, Tromsø, Norway; Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden; and Genetic Epidemiology Group, Folkhälsan Research Center, Helsinki, Finland.
| | | | - Tracey J Woodruff
- Program on Reproductive Health and the Environment, University of California, San Francisco, USA
| | | | - Il Je Yu
- Institute of Nanoproduct Safety Research, Hoseo University, Asan, The Republic of Korea
| | | | - Hajo Zeeb
- Department of Prevention and Evaluation, Leibniz-Institute for Prevention Research and Epidemiology, Bremen, Germany
| | - Shu-Feng Zhou
- College of Pharmacy, University of South Florida, Tampa, Florida, USA
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19
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Silva JM, Deuker MM, Baguley BC, McMahon M. Abstract 29: MEK and PI3K signaling cooperate through mTORC1/2 to promote PIK3CA mutant melanoma cell proliferation. Cancer Res 2016. [DOI: 10.1158/1538-7445.am2016-29] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Oncogenic transformation of mutationally activated BRAF or NRAS melanocytes often requires the cooperation of genetic aberrations in the phosphoinositide 3-kinase (PI3K) pathway to promote melanomagenesis. Activating point mutations in the p110α catalytic subunit of PI3K are detected at a low frequency in both BRAF and NRAS mutant melanomas, yet the principle mechanism of this cooperation remains elusive. Thus, using BRAFV600E/PIK3CAH1047R, NRASQ61H/PIK3CAH1047R, and PIK3CAE545K mutant melanoma cells derived from metastatic melanoma patients treated with pathway-targeted inhibitors, we examined the contribution of mutational activation of PIK3CA to melanoma maintenance and signaling and the consequential response of these PIK3CA mutant cells to α-specific PI3K inhibition. Combined MEK and isoform-selective PI3K inhibition elicited more potent anti-proliferative effects and greater suppression of S-phase progression of the cell cycle compared to single-agent inhibition of either pathway. Analysis of signaling downstream of MEK or PI3K revealed that these pathways cooperated to regulate PIK3CA cell proliferation through mTORC1-mediated effects on ribosomal protein S6 and 4E-BP1 phosphorylation in an AKT-dependent manner. Despite the profound anti-proliferative and biochemical effects of α-specific or PI3Kβ-sparing class I PI3K inhibition in vitro, these agents elicited largely cytostatic effects on PIK3CA xenograft tumors. However, combined inhibition of PI3Kβ-sparing class I PI3K and MEK did significantly cooperate to reduce tumor growth compared to the corresponding monotherapies. Furthermore, this study provides a biochemical mechanism to explain how mTORC1/2 moderates the cooperation of MEK and PI3K signaling for the maintenance of PIK3CA mutant melanoma cell proliferation.
Citation Format: Jillian M. Silva, Marian M. Deuker, Bruce C. Baguley, Martin McMahon. MEK and PI3K signaling cooperate through mTORC1/2 to promote PIK3CA mutant melanoma cell proliferation. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 29.
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Affiliation(s)
| | | | | | - Martin McMahon
- 1University of California, San Francisco, San Francisco, CA
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20
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Reynisson J, Jaiswal JK, Barker D, D'mello SAN, Denny WA, Baguley BC, Leung EY. Evidence that phospholipase C is involved in the antitumour action of NSC768313, a new thieno[2,3-b]pyridine derivative. Cancer Cell Int 2016; 16:18. [PMID: 26966420 PMCID: PMC4785615 DOI: 10.1186/s12935-016-0293-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Accepted: 03/01/2016] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND The thieno[2,3-b]pyridines were discovered by virtual high throughput screening as potential inhibitors of phospholipase C (PLC) isoforms and showed potent growth inhibitory effects in National Cancer Institute's human tumour cell line panel (NCI60). The mechanism of the anti-proliferative activity of thieno[2,3-b]pyridines is explored here. OBJECTIVES We aimed to investigate the basis for the anti-proliferative activity of these thieno[2,3-b]pyridines and to determine whether the cellular inhibition was related to their inhibition of PLC. METHODS Four breast cancer cell lines were used to assess the anti-proliferative effects (IC50 values) of six representative thieno[2,3-b]pyridines. The most potent compound (derivative 3; NSC768313), was further studied in MDA-MB-231 cells. DNA damage was examined by γH2AX expression level, and cell cycle arrest by flow cytometry. Cell morphology was examined by tubulin antibody staining. The growth inhibitory effect of combination treatment with derivative 3 and paclitaxel (tubulin inhibitor), doxorubicin (topoisomerase II inhibitor) or camptothecin (topoisomerase I inhibitor) was evaluated. A preliminary mouse toxicity assay was used to evaluate the pharmacological properties. RESULTS Addition of the thieno[2,3-b]pyridine derivative 3 to the MDA-MB-231 cells induced G2/M growth inhibition, cell cycle arrest in G2-phase, membrane blebbing and the formation of multinucleated cells. It did not induce DNA damage, mitotic arrest or changes in calcium ion flux. Combination of derivative 3 with paclitaxel showed a high degree of synergy, while combinations with doxorubicin and camptothecin showed only additive effects. A mouse pharmacokinetic study of derivative 3 showed that after intraperitoneal injection of a single does (10 mg/Kg), the Cmax was 0.087 μmol/L and the half-life was 4.11 h. CONCLUSIONS The results are consistent with a mechanism in which thieno[2,3-b]pyridine derivatives interact with PLC isoforms (possibly PLC-δ), which in turn affect the cellular dynamics of tubulin-β, inducing cell cycle arrest in G2-phase. We conclude that these compounds have novelty because of their PLC target and may have utility in combination with mitotic poisons for cancer treatment.
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Affiliation(s)
- Jóhannes Reynisson
- School of Chemical Sciences, University of Auckland, Auckland, New Zealand
| | - Jagdish K Jaiswal
- Auckland Cancer Society Research Centre, University of Auckland, Private Bag 92019, Auckland, 1142 New Zealand
| | - David Barker
- School of Chemical Sciences, University of Auckland, Auckland, New Zealand
| | - Stacey A N D'mello
- Auckland Cancer Society Research Centre, University of Auckland, Private Bag 92019, Auckland, 1142 New Zealand ; Molecular Medicine and Pathology Department, University of Auckland, Private Bag 92019, Auckland, 1142 New Zealand
| | - William A Denny
- Auckland Cancer Society Research Centre, University of Auckland, Private Bag 92019, Auckland, 1142 New Zealand
| | - Bruce C Baguley
- Auckland Cancer Society Research Centre, University of Auckland, Private Bag 92019, Auckland, 1142 New Zealand
| | - Euphemia Y Leung
- Auckland Cancer Society Research Centre, University of Auckland, Private Bag 92019, Auckland, 1142 New Zealand ; Molecular Medicine and Pathology Department, University of Auckland, Private Bag 92019, Auckland, 1142 New Zealand
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21
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Portier CJ, Armstrong BK, Baguley BC, Baur X, Belyaev I, Bellé R, Belpoggi F, Biggeri A, Bosland MC, Bruzzi P, Budnik LT, Bugge MD, Burns K, Calaf GM, Carpenter DO, Carpenter HM, López-Carrillo L, Clapp R, Cocco P, Consonni D, Comba P, Craft E, Dalvie MA, Davis D, Demers PA, De Roos AJ, DeWitt J, Forastiere F, Freedman JH, Fritschi L, Gaus C, Gohlke JM, Goldberg M, Greiser E, Hansen J, Hardell L, Hauptmann M, Huang W, Huff J, James MO, Jameson CW, Kortenkamp A, Kopp-Schneider A, Kromhout H, Larramendy ML, Landrigan PJ, Lash LH, Leszczynski D, Lynch CF, Magnani C, Mandrioli D, Martin FL, Merler E, Michelozzi P, Miligi L, Miller AB, Mirabelli D, Mirer FE, Naidoo S, Perry MJ, Petronio MG, Pirastu R, Portier RJ, Ramos KS, Robertson LW, Rodriguez T, Röösli M, Ross MK, Roy D, Rusyn I, Saldiva P, Sass J, Savolainen K, Scheepers PTJ, Sergi C, Silbergeld EK, Smith MT, Stewart BW, Sutton P, Tateo F, Terracini B, Thielmann HW, Thomas DB, Vainio H, Vena JE, Vineis P, Weiderpass E, Weisenburger DD, Woodruff TJ, Yorifuji T, Yu IJ, Zambon P, Zeeb H, Zhou SF. Differences in the carcinogenic evaluation of glyphosate between the International Agency for Research on Cancer (IARC) and the European Food Safety Authority (EFSA). J Epidemiol Community Health 2016. [PMID: 26941213 DOI: 10.1136/jech-2015-207005.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
| | | | | | - Xaver Baur
- Charité University Medicine Berlin, Berlin, Germany
| | - Igor Belyaev
- Cancer Research Institute, Bratislava, Slovak Republic
| | - Robert Bellé
- Sorbonne Universités, UPMC Univ Paris 06, UMR8227, Roscoff, France
| | | | - Annibale Biggeri
- Institute for Cancer Prevention and Research, University of Florence, Italy
| | | | - Paolo Bruzzi
- National Cancer Research Institute, San Martino-IST Hospital, Genoa, Italy
| | | | - Merete D Bugge
- STAMI, National Institute of Occupational Health, Oslo, Norway
| | | | - Gloria M Calaf
- Instituto de Alta Investigación, Universidad de Tarapacá, Arica, Chile
| | - David O Carpenter
- Institute for Health and the Environment, University at Albany, Rensselaer, New York, USA
| | | | | | - Richard Clapp
- Boston University School of Public Health, Boston, Massachusetts, USA
| | - Pierluigi Cocco
- Department of Public Health, Clinical and Molecular Medicine, University of Cagliari, Cagliari, Italy
| | - Dario Consonni
- Department of Preventive Medicine, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Pietro Comba
- Department of Environment and Primary Prevention, IstitutoSuperiore di Sanità, Rome, Italy
| | - Elena Craft
- Environmental Defense Fund, Austin, Texas, USA
| | - Mohamed Aqiel Dalvie
- Center for Environmental and Occupational Health, University of Cape Town, Cape Town, South Africa
| | - Devra Davis
- Environmental Health Trust, Jackson Hole, Wyoming, USA and The Hebrew University Hadassah School of Medicine, Jerusalem, Israel
| | - Paul A Demers
- Dalla Lana School of Public Health, University of Toronto, Canada
| | - Anneclaire J De Roos
- Department of Environmental and Occupational Health, Drexel University, Philadelphia, Pennsylvania, USA
| | - Jamie DeWitt
- Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | | | | | - Lin Fritschi
- School of Public Health, Curtin University, Perth, Western Australia, Australia
| | - Caroline Gaus
- Department of Environmental Toxicology, The University of Queensland, Brisbane, Australia
| | - Julia M Gohlke
- Department of Population Health Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | | | | | - Johnni Hansen
- Danish Cancer Society Research Center, Copenhagen, Denmark
| | | | - Michael Hauptmann
- Biostatistics Branch, Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Wei Huang
- Faculty of Department of Occupational and Environmental Health, Peking Univ School of Public Health, Beijing, China
| | - James Huff
- National Institute for Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | | | - C W Jameson
- CWJ Consulting, LLC, Cape Coral, Florida, USA
| | - Andreas Kortenkamp
- Institute of Environment, Health and Societies, Brunel University London, London, UK
| | | | - Hans Kromhout
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands
| | - Marcelo L Larramendy
- National Council of Scientific and Technological Research, National University of La Plata, Argentina
| | - Philip J Landrigan
- Arnhold Institute for Global Health, Icahn School of Medicine at Mount Sinai, New York, USA
| | - Lawrence H Lash
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | | | - Charles F Lynch
- Department of Epidemiology, University of Iowa, Iowa City, Iowa, USA
| | - Corrado Magnani
- Cancer Epidemiology Unit, University of Eastern Piedmont, Novara, Italy
| | | | | | - Enzo Merler
- Department of Prevention, Occupational Health Unit, National Health Service, Padua, Italy
| | | | - Lucia Miligi
- Occupational and Environmental Epidemiology Unit, ISPO-Cancer Prevention and Research Institute, Florence, Italy
| | - Anthony B Miller
- Dalla Lana School of Public Health, University of Toronto, Canada
| | - Dario Mirabelli
- Unit of Cancer Epidemiology, University of Turin and CPO-Piemonte, Torino, Italy
| | - Franklin E Mirer
- Department of Environmental and Occupational Health Sciences, City University of New York School of Public Health, USA
| | - Saloshni Naidoo
- School of Nursing and Public Health, University of KwaZulu-Natal, Durban, South Africa
| | - Melissa J Perry
- Department of Environmental and Occupational Health, Milken Institute School of Public Health, The George Washington University, Washington DC, USA
| | - Maria Grazia Petronio
- Health and Environment-Department of Prevention, Local Health Authority-Empoli, Florence, Italy
| | - Roberta Pirastu
- Department of Biology and Biotechnology "Charles Darwin", Sapienza Rome University, Italy
| | - Ralph J Portier
- Department of Environmental Sciences, School of the Coast & Environment, Louisiana State University, Baton Rouge, Los Angeles, USA
| | - Kenneth S Ramos
- Center for Applied Genetics and Genomic Medicine, University of Arizona Health Sciences, Tucson, Arizona, USA
| | - Larry W Robertson
- Iowa Superfund Research Program and the Interdisciplinary Graduate Program in Human Toxicology, University of Iowa, Iowa City, Iowa, USA
| | - Theresa Rodriguez
- Center for Research in Health, Work and Environment (CISTA), National Autonomous University of Nicaragua (UNAN-León), León, Nicaragua
| | - Martin Röösli
- Swiss Tropical and Public Health Institute, Associated Institute of the University of Basel, Basel, Switzerland
| | - Matt K Ross
- College of Veterinary Medicine, Mississippi State University, Mississippi State, USA
| | - Deodutta Roy
- Department of Environmental and Occupational Health, Florida International University, Miami, Florida, USA
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas, USA
| | - Paulo Saldiva
- Faculty of Medicine, University of São Paulo, São Paulo, Brazil
| | - Jennifer Sass
- Natural Resources Defense Council and George Washington University, Washington DC, USA
| | - Kai Savolainen
- Nanosafety Research Centre, Finnish Institute of Occupational Health, Helsinki, Finland
| | - Paul T J Scheepers
- Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Consolato Sergi
- Department of Pathology, University of Alberta, Edmonton, Alberta, Canada
| | - Ellen K Silbergeld
- Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Martyn T Smith
- School of Public Health, University of California, Berkeley, California, USA
| | - Bernard W Stewart
- Faculty of Medicine, University of New South Wales, Randwick, New South Wales Australia
| | - Patrice Sutton
- Program on Reproductive Health and the Environment, University of California, San Francisco, California, USA
| | - Fabio Tateo
- Istituto di Geosceinze e Georisorse (CNR), Padova, Italy
| | | | - Heinz W Thielmann
- German Cancer Research Center, Heidelberg and Faculty of Pharmacy, Heidelberg University, Germany
| | - David B Thomas
- Fred Hutchinson Cancer Research Center, University of Washington, Seattle, Washington, USA
| | - Harri Vainio
- Faculty of Public Health, Kuwait University, Kuwait City, Kuwait
| | - John E Vena
- Department of Public Health Sciences, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Paolo Vineis
- Department of Environmental Epidemiology, Imperial College London, London, UK
| | - Elisabete Weiderpass
- Department of Research, Cancer Registry of Norway, Institute of Population-Based Cancer Research, Oslo, Norway; Department of Community Medicine, Faculty of Health Sciences, University of Tromsø, The Arctic University of Norway, Tromsø, Norway; Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden; and Genetic Epidemiology Group, Folkhälsan Research Center, Helsinki, Finland
| | | | - Tracey J Woodruff
- Program on Reproductive Health and the Environment, University of California, San Francisco, USA
| | | | - Il Je Yu
- Institute of Nanoproduct Safety Research, Hoseo University, Asan, The Republic of Korea
| | | | - Hajo Zeeb
- Department of Prevention and Evaluation, Leibniz-Institute for Prevention Research and Epidemiology, Bremen, Germany
| | - Shu-Feng Zhou
- College of Pharmacy, University of South Florida, Tampa, Florida, USA
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22
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Abstract
Recent genomic and transcriptomic analysis has revealed that the majority of the human genome is transcribed as nonprotein-coding RNA. These transcripts, known as long noncoding RNA, have structures similar to those of mRNA. Many of these transcripts are now thought to have regulatory roles in different biological pathways which provide cells with an additional layer of regulatory complexity in gene expression and proteome function in response to stimuli. A wide variety of cellular functions may thus depend on the fine-tuning of interactions between noncoding RNAs and other key molecules in cell signaling networks. Deregulation of many noncoding RNAs is thought to occur in a variety of human diseases, including neoplasia and cancer drug resistance. Here we discuss recent findings on the molecular functions of long noncoding RNAs in cellular pathways mediating resistance to anticancer drugs.
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Affiliation(s)
- Marjan E Askarian-Amiri
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Road, Grafton, Auckland, 1023, New Zealand. .,Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand.
| | - Euphemia Leung
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Road, Grafton, Auckland, 1023, New Zealand.,Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Graeme Finlay
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Road, Grafton, Auckland, 1023, New Zealand.,Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Bruce C Baguley
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Road, Grafton, Auckland, 1023, New Zealand
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23
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Abstract
The development and progression of melanoma have been attributed to independent or combined genetic and epigenetic events. There has been remarkable progress in understanding melanoma pathogenesis in terms of genetic alterations. However, recent studies have revealed a complex involvement of epigenetic mechanisms in the regulation of gene expression, including methylation, chromatin modification and remodeling, and the diverse activities of non-coding RNAs. The roles of gene methylation and miRNAs have been relatively well studied in melanoma, but other studies have shown that changes in chromatin status and in the differential expression of long non-coding RNAs can lead to altered regulation of key genes. Taken together, they affect the functioning of signaling pathways that influence each other, intersect, and form networks in which local perturbations disturb the activity of the whole system. Here, we focus on how epigenetic events intertwine with these pathways and contribute to the molecular pathogenesis of melanoma.
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Key Words
- 5hmC, 5-hydroxymethylcytosine
- 5mC, 5-methylcytosine
- ACE, angiotensin converting enzyme
- ANCR, anti-differentiation non-coding RNA
- ANRIL, antisense noncoding RNA in INK4 locus
- ASK1, apoptosis signal-regulating kinase 1
- ATRA, all-trans retinoic acid
- BANCR, BRAF-activated non-coding RNA
- BCL-2, B-cell lymphoma 2
- BRAF, B-Raf proto-oncogene, serine/threonine kinase
- BRG1, ATP-dependent helicase SMARCA4
- CAF-1, chromatin assembly factor-1
- CBX7, chromobox homolog 7
- CCND1, cyclin D1
- CD28, cluster of differentiation 28
- CDK, cyclin-dependent kinase
- CDKN2A/B, cyclin-dependent kinase inhibitor 2A/B
- CHD8, chromodomain-helicase DNA-binding protein 8
- CREB, cAMP response element-binding protein
- CUDR, cancer upregulated drug resistant
- Cdc6, cell division cycle 6
- DNA methylation/demethylation
- DNMT, DNA methyltransferase
- EMT, epithelial-mesenchymal transition
- ERK, extracellular signal-regulated kinase
- EZH2, enhancer of zeste homolog 2
- GPCRs, G-protein coupled receptors
- GSK3a, glycogen synthase kinase 3 α
- GWAS, genome-wide association study
- HDAC, histone deacetylase
- HOTAIR, HOX antisense intergenic RNA
- IAP, inhibitor of apoptosis
- IDH2, isocitrate dehydrogenase
- IFN, interferon, interleukin 23
- JNK, Jun N-terminal kinase
- Jak/STAT, Janus kinase/signal transducer and activator of transcription
- MAFG, v-maf avian musculoaponeurotic fibrosarcoma oncogene homolog G
- MALAT1, metastasis-associated lung adenocarcinoma transcript 1
- MAPK, mitogen-activated protein kinase
- MC1R, melanocortin-1 receptor
- MGMT, O6-methylguanine-DNA methyltransferase
- MIF, macrophage migration inhibitory factor
- MITF, microphthalmia-associated transcription factor
- MRE, miRNA recognition element
- MeCP2, methyl CpG binding protein 2
- NF-κB, nuclear factor kappa-light-chain-enhancer of activated B cells
- NOD, nucleotide-binding and oligomerization domain
- PBX, pre-B-cell leukemia homeobox
- PEDF, pigment epithelium derived factor
- PI3K, phosphatidylinositol-4, 5-bisphosphate 3-kinase
- PIB5PA, phosphatidylinositol-4, 5-biphosphate 5-phosphatase A
- PKA, protein kinase A
- PRC, polycomb repressor complex
- PSF, PTB associated splicing factor
- PTB, polypyrimidine tract-binding
- PTEN, phosphatase and tensin homolog
- RARB, retinoic acid receptor-β2
- RASSF1A, Ras association domain family 1A
- SETDB1, SET Domain, bifurcated 1
- SPRY4, Sprouty 4
- STAU1, Staufen1
- SWI/SNF, SWItch/Sucrose Non-Fermentable
- TCR, T-cell receptor
- TET, ten eleven translocase
- TGF β, transforming growth factor β
- TINCR, tissue differentiation-inducing non-protein coding RNA
- TOR, target of rapamycin
- TP53, tumor protein 53
- TRAF6, TNF receptor-associated factor 6
- UCA1, urothelial carcinoma-associated 1
- ceRNA, competitive endogenous RNAs
- chromatin modification
- chromatin remodeling
- epigenetics
- gene regulation
- lncRNA, long ncRNA
- melanoma
- miRNA, micro RNA
- ncRNA, non-coding RNA
- ncRNAs
- p14ARF, p14 alternative reading frame
- p16INK4a, p16 inhibitor of CDK4
- pRB, retinoblastoma protein
- snoRNA, small nucleolar RNA
- α-MSHm, α-melanocyte stimulating hormone
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Affiliation(s)
- Debina Sarkar
- a Auckland Cancer Society Research Center ; University of Auckland ; Auckland , New Zealand
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Leung EY, Askarian-Amiri M, Finlay GJ, Rewcastle GW, Baguley BC. Potentiation of Growth Inhibitory Responses of the mTOR Inhibitor Everolimus by Dual mTORC1/2 Inhibitors in Cultured Breast Cancer Cell Lines. PLoS One 2015; 10:e0131400. [PMID: 26148118 PMCID: PMC4492962 DOI: 10.1371/journal.pone.0131400] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2015] [Accepted: 06/01/2015] [Indexed: 11/19/2022] Open
Abstract
The mammalian target of rapamycin (mTOR), a vital component of signaling pathways involving PI3K/AKT, is an attractive therapeutic target in breast cancer. Everolimus, an allosteric mTOR inhibitor that inhibits the mTOR functional complex mTORC1, is approved for treatment of estrogen receptor positive (ER+) breast cancer. Other mTOR inhibitors show interesting differences in target specificities: BEZ235 and GSK2126458 are ATP competitive mTOR inhibitors targeting both PI3K and mTORC1/2; AZD8055, AZD2014 and KU-0063794 are ATP competitive mTOR inhibitors targeting both mTORC1 and mTORC2; and GDC-0941 is a pan-PI3K inhibitor. We have addressed the question of whether mTOR inhibitors may be more effective in combination than singly in inhibiting the proliferation of breast cancer cells. We selected a panel of 30 human breast cancer cell lines that included ER and PR positive, HER2 over-expressing, and “triple negative” variants, and determined whether signaling pathway utilization was related to drug-induced inhibition of proliferation. A significant correlation (p = 0.005) was found between everolimus IC50 values and p70S6K phosphorylation, but not with AKT or ERK phosphorylation, consistent with the mTOR pathway being a principal target. We then carried out combination studies with four everolimus resistant triple-negative breast cancer cell lines, and found an unexpectedly high degree of synergy between everolimus and the other inhibitors tested. The level of potentiation of everolimus inhibitory activity (measured by IC50 values) was found to be cell line-specific for all the kinase inhibitors tested. The results suggest that judicious combination of mTOR inhibitors with different modes of action could have beneficial effects in the treatment of breast cancer.
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Affiliation(s)
- Euphemia Y. Leung
- Auckland Cancer Society Research Centre, University of Auckland, Grafton, Auckland, New Zealand
- Department of Molecular Medicine and Pathology, University of Auckland, Grafton, Auckland, New Zealand
- * E-mail: (EL); (BB)
| | - Marjan Askarian-Amiri
- Auckland Cancer Society Research Centre, University of Auckland, Grafton, Auckland, New Zealand
- Department of Molecular Medicine and Pathology, University of Auckland, Grafton, Auckland, New Zealand
| | - Graeme J. Finlay
- Auckland Cancer Society Research Centre, University of Auckland, Grafton, Auckland, New Zealand
- Department of Molecular Medicine and Pathology, University of Auckland, Grafton, Auckland, New Zealand
| | - Gordon W. Rewcastle
- Auckland Cancer Society Research Centre, University of Auckland, Grafton, Auckland, New Zealand
| | - Bruce C. Baguley
- Auckland Cancer Society Research Centre, University of Auckland, Grafton, Auckland, New Zealand
- * E-mail: (EL); (BB)
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25
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Sweetlove M, Wrightson E, Kolekar S, Rewcastle GW, Baguley BC, Shepherd PR, Jamieson SMF. Inhibitors of pan-PI3K Signaling Synergize with BRAF or MEK Inhibitors to Prevent BRAF-Mutant Melanoma Cell Growth. Front Oncol 2015; 5:135. [PMID: 26137449 PMCID: PMC4468830 DOI: 10.3389/fonc.2015.00135] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 06/01/2015] [Indexed: 11/13/2022] Open
Abstract
BRAF and MEK inhibitors have improved outcomes for patients with BRAF-mutant melanoma, but their efficacy is limited by both intrinsic and acquired resistances. Activation of the PI3K pathway can mediate resistance to these agents, providing a strong rationale for combination therapy in melanoma. Here, a panel of nine low-passage human metastatic melanoma cell lines with BRAF mutations was tested in cell proliferation and protein expression assays for sensitivity to inhibitors of MEK (selumetinib) and BRAF (vemurafenib) as single agents and in combination with inhibitors of pan-PI3K (ZSTK474), pan-PI3K/mTOR (BEZ235), individual PI3K isoforms (p110α, A66; p110β, TGX-221; p110γ, AS-252424; p110δ, idelalisib), or mTORC1/2 (KU-0063794). Selumetinib and vemurafenib potently inhibited cell proliferation in all cell lines, especially in those that expressed low levels of phosphorylated AKT (pAKT). ZSTK474 and BEZ235 also inhibited cell proliferation in all cell lines and enhanced the antitumor activity of selumetinib and vemurafenib in the majority of lines by either interacting synergistically or additively to increase potency or by inducing cytotoxicity by significantly increasing the magnitude of cell growth inhibition. Furthermore, ZSTK474 or BEZ235 combined with selumetinib to produce robust inhibition of pERK, pAKT, and pS6 expression and synergistic inhibition of NZM20 tumor growth. The inhibitors of individual PI3K isoforms or mTORC1/2 were less effective at inhibiting cell proliferation either as single agents or in combination with selumetinib or vemurafenib, although KU-0063794 synergistically interacted with vemurafenib and increased the magnitude of cell growth inhibition with selumetinib or vemurafenib in certain cell lines. Overall, these results suggest that the sensitivity of BRAF-mutant melanoma cells to BRAF or MEK inhibitors is at least partly mediated by activation of the PI3K pathway and can be enhanced by combined inhibition of the BRAF/MEK and PI3K/mTOR signaling pathways.
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Affiliation(s)
- Melanie Sweetlove
- Auckland Cancer Society Research Centre, The University of Auckland , Auckland , New Zealand
| | - Emma Wrightson
- Auckland Cancer Society Research Centre, The University of Auckland , Auckland , New Zealand
| | - Sharada Kolekar
- Department of Molecular Medicine and Pathology, The University of Auckland , Auckland , New Zealand
| | - Gordon W Rewcastle
- Auckland Cancer Society Research Centre, The University of Auckland , Auckland , New Zealand ; Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland , Auckland , New Zealand
| | - Bruce C Baguley
- Auckland Cancer Society Research Centre, The University of Auckland , Auckland , New Zealand ; Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland , Auckland , New Zealand
| | - Peter R Shepherd
- Department of Molecular Medicine and Pathology, The University of Auckland , Auckland , New Zealand ; Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland , Auckland , New Zealand
| | - Stephen M F Jamieson
- Auckland Cancer Society Research Centre, The University of Auckland , Auckland , New Zealand ; Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland , Auckland , New Zealand
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Zhang W, Wang G, See E, Shaw JP, Baguley BC, Liu J, Amirapu S, Wu Z. Post-insertion of poloxamer 188 strengthened liposomal membrane and reduced drug irritancy and in vivo precipitation, superior to PEGylation. J Control Release 2015; 203:161-9. [PMID: 25701612 DOI: 10.1016/j.jconrel.2015.02.026] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 01/29/2015] [Accepted: 02/17/2015] [Indexed: 02/05/2023]
Abstract
The ultimate aim of this study was to develop asulacrine (ASL)-loaded long-circulating liposomes to prevent phlebitis during intravenous (i.v.) infusion for chemotherapy. Poly(ethylene)glycol (PEG) and poloxamer 188-modified liposomes (ASL-PEGL and ASL-P188L) were developed, and ASL was loaded using a remote loading method facilitated with a low concentration of sulfobutyl ether-β-cyclodextrin as a drug solubilizer. The liposomes were characterized in terms of morphology, size, release properties and stability. Pharmacokinetics and venous tissue tolerance of the formulations were simultaneously studied in rabbits following one-hour i.v. infusion via the ear vein. The irritancy was assessed using a rat paw-lift/lick model after subplantar injections. High drug loading 9.0% w/w was achieved with no drug leakage found from ASL-PEGL or ASL-P188L suspended in a 5% glucose solution at 30days. However, a rapid release (leakage) from ASL-PEGL was observed when PBS was used as release medium, partially related to the use of cyclodextrin in drug loading. Post-insertion of poloxamer 188 to the liposomes appeared to be able to restore the drug retention possibly by increasing the packing density of phospholipids in the membrane. In rabbits (n=5), ASL-P188L had a prolonged half-life with no drug precipitation or inflammation in the rabbit ear vein in contrast to ASL solution. Following subplantar (footpad) injections in rats ASL solution induced paw-lick/lift responses in all rats whereas ASL-P188L caused no response (n=8). PEGylation showed less benefit possibly due to the drug 'leakage'. In conclusion, drug precipitation in the vein and the drug mild irritancy may both contribute to the occurrence of phlebitis caused by the ASL solution, and could both be prevented by encapsulation of the drug in liposomes. Poloxamer 188 appeared to be able to 'seal' the liposomal membrane and enhance drug retention. The study also highlighted the importance of bio-relevant in vitro release study in formulation screening.
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Affiliation(s)
- Wenli Zhang
- School of Pharmacy, The University of Auckland, Private Bag 92019, Auckland, New Zealand; China Pharmaceutical University, Nanjing 210009, PR China
| | - Guangji Wang
- China Pharmaceutical University, Nanjing 210009, PR China
| | - Esther See
- School of Pharmacy, The University of Auckland, Private Bag 92019, Auckland, New Zealand
| | - John P Shaw
- School of Pharmacy, The University of Auckland, Private Bag 92019, Auckland, New Zealand
| | - Bruce C Baguley
- Auckland Cancer Society Research Centre, The University of Auckland, Private Bag 92019, Auckland, New Zealand
| | - Jianping Liu
- China Pharmaceutical University, Nanjing 210009, PR China.
| | - Satya Amirapu
- Anatomy, Medical Sciences, The University of Auckland, Private Bag 92019, Auckland, New Zealand
| | - Zimei Wu
- School of Pharmacy, The University of Auckland, Private Bag 92019, Auckland, New Zealand.
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27
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Burd CE, Liu W, Huynh MV, Waqas MA, Gillahan JE, Clark KS, Fu K, Martin BL, Jeck WR, Souroullas GP, Darr DB, Zedek DC, Miley MJ, Baguley BC, Campbell SL, Sharpless NE. Mutation-specific RAS oncogenicity explains NRAS codon 61 selection in melanoma. Cancer Discov 2014; 4:1418-29. [PMID: 25252692 PMCID: PMC4258185 DOI: 10.1158/2159-8290.cd-14-0729] [Citation(s) in RCA: 137] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
UNLABELLED NRAS mutation at codons 12, 13, or 61 is associated with transformation; yet, in melanoma, such alterations are nearly exclusive to codon 61. Here, we compared the melanoma susceptibility of an NrasQ61R knock-in allele to similarly designed KrasG12D and NrasG12D alleles. With concomitant p16INK4a inactivation, KrasG12D or NrasQ61R expression efficiently promoted melanoma in vivo, whereas NrasG12D did not. In addition, NrasQ61R mutation potently cooperated with Lkb1/Stk11 loss to induce highly metastatic disease. Functional comparisons of NrasQ61R and NrasG12D revealed little difference in the ability of these proteins to engage PI3K or RAF. Instead, NrasQ61R showed enhanced nucleotide binding, decreased intrinsic GTPase activity, and increased stability when compared with NrasG12D. This work identifies a faithful model of human NRAS-mutant melanoma, and suggests that the increased melanomagenecity of NrasQ61R over NrasG12D is due to heightened abundance of the active, GTP-bound form rather than differences in the engagement of downstream effector pathways. SIGNIFICANCE This work explains the curious predominance in human melanoma of mutations of codon 61 of NRAS over other oncogenic NRAS mutations. Using conditional "knock-in" mouse models, we show that physiologic expression of NRASQ61R, but not NRASG12D, drives melanoma formation.
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Affiliation(s)
- Christin E Burd
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio. Department of Molecular and Cellular Biochemistry, The Ohio State University, Columbus, Ohio
| | - Wenjin Liu
- Department of Genetics, University of North Carolina School of Medicine, Chapel Hill, North Carolina. The Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Minh V Huynh
- Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Meriam A Waqas
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio
| | - James E Gillahan
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio. Department of Molecular and Cellular Biochemistry, The Ohio State University, Columbus, Ohio
| | - Kelly S Clark
- Department of Genetics, University of North Carolina School of Medicine, Chapel Hill, North Carolina. The Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Kailing Fu
- Department of Genetics, University of North Carolina School of Medicine, Chapel Hill, North Carolina. The Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Brit L Martin
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio
| | - William R Jeck
- Department of Genetics, University of North Carolina School of Medicine, Chapel Hill, North Carolina. The Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - George P Souroullas
- Department of Genetics, University of North Carolina School of Medicine, Chapel Hill, North Carolina. The Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - David B Darr
- Department of Genetics, University of North Carolina School of Medicine, Chapel Hill, North Carolina. The Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Daniel C Zedek
- Department of Dermatology, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Michael J Miley
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Bruce C Baguley
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Sharon L Campbell
- The Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina. Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Norman E Sharpless
- Department of Genetics, University of North Carolina School of Medicine, Chapel Hill, North Carolina. The Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina.
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Baguley BC, Ding Q, Richardson E. Preliminary Evidence That High-Dose Vitamin C has a Vascular Disrupting Action in Mice. Front Oncol 2014; 4:310. [PMID: 25414833 PMCID: PMC4220656 DOI: 10.3389/fonc.2014.00310] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 10/18/2014] [Indexed: 12/20/2022] Open
Abstract
High intravenous doses of vitamin C (ascorbic acid) have been reported to benefit cancer patients, but the data are controversial and there is incomplete knowledge of what physiological mechanisms might be involved in any response. Vitamin C is taken up efficiently by cells expressing SVCT2 transporters and since vascular endothelial cells express SVCT2, we explored the hypothesis that administration of high-dose vitamin C (up to 5 g/kg) to mice might affect vascular endothelial function. A single administration of vitamin C to mice induced time- and dose-dependent increases in plasma concentrations of the serotonin metabolite 5-hydroxyindole acetic acid (5-HIAA), a marker for vascular disrupting effects. Responses were comparable to those for the tumor vascular disrupting agents, vadimezan and fosbretabulin. High-dose vitamin C administration decreased tumor serotonin concentrations, consistent with the release of serotonin from platelets and its metabolism to 5-HIAA. High-dose vitamin C also significantly increased the degree of hemorrhagic necrosis in tumors removed after 24 h, and significantly decreased tumor volume after 2 days. However, the effect on tumor growth was temporary. The results support the concept that vitamin C at high dose increases endothelial permeability, allowing platelets to escape and release serotonin. Plasma 5-HIAA concentrations could provide a pharmacodynamic biomarker for vitamin C effects in clinical studies.
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Affiliation(s)
- Bruce C Baguley
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland , Auckland , New Zealand
| | - Qi Ding
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland , Auckland , New Zealand
| | - Emma Richardson
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland , Auckland , New Zealand
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29
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Hansji H, Leung EY, Baguley BC, Finlay GJ, Askarian-Amiri ME. Keeping abreast with long non-coding RNAs in mammary gland development and breast cancer. Front Genet 2014; 5:379. [PMID: 25400658 PMCID: PMC4215690 DOI: 10.3389/fgene.2014.00379] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Accepted: 10/13/2014] [Indexed: 12/18/2022] Open
Abstract
The majority of the human genome is transcribed, even though only 2% of transcripts encode proteins. Non-coding transcripts were originally dismissed as evolutionary junk or transcriptional noise, but with the development of whole genome technologies, these non-coding RNAs (ncRNAs) are emerging as molecules with vital roles in regulating gene expression. While shorter ncRNAs have been extensively studied, the functional roles of long ncRNAs (lncRNAs) are still being elucidated. Studies over the last decade show that lncRNAs are emerging as new players in a number of diseases including cancer. Potential roles in both oncogenic and tumor suppressive pathways in cancer have been elucidated, but the biological functions of the majority of lncRNAs remain to be identified. Accumulated data are identifying the molecular mechanisms by which lncRNA mediates both structural and functional roles. LncRNA can regulate gene expression at both transcriptional and post-transcriptional levels, including splicing and regulating mRNA processing, transport, and translation. Much current research is aimed at elucidating the function of lncRNAs in breast cancer and mammary gland development, and at identifying the cellular processes influenced by lncRNAs. In this paper we review current knowledge of lncRNAs contributing to these processes and present lncRNA as a new paradigm in breast cancer development.
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Affiliation(s)
- Herah Hansji
- Auckland Cancer Society Research Centre, University of Auckland Auckland, New Zealand
| | - Euphemia Y Leung
- Auckland Cancer Society Research Centre, University of Auckland Auckland, New Zealand
| | - Bruce C Baguley
- Auckland Cancer Society Research Centre, University of Auckland Auckland, New Zealand
| | - Graeme J Finlay
- Auckland Cancer Society Research Centre, University of Auckland Auckland, New Zealand ; Department of Molecular Medicine and Pathology, University of Auckland Auckland, New Zealand
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Zhang W, Wang G, Falconer JR, Baguley BC, Shaw JP, Liu J, Xu H, See E, Sun J, Aa J, Wu Z. Strategies to maximize liposomal drug loading for a poorly water-soluble anticancer drug. Pharm Res 2014; 32:1451-61. [PMID: 25355460 DOI: 10.1007/s11095-014-1551-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2014] [Accepted: 10/10/2014] [Indexed: 11/27/2022]
Abstract
PURPOSE To develop a liposomal system with high drug loading (DL) for intravenous (i.v.) delivery of a poorly water-soluble basic drug, asulacrine (ASL). METHODS A thin-film hydration and extrusion method was used to fabricate the PEGylated liposomal membranes followed by a freeze and thaw process. A novel active drug loading method was developed using ammonium sulphate gradient as an influx driving force of ASL solubilized with sulfobutyl ether-β-cyclodextrin (SBE-β-CD). DL was maximized by optimizing liposomal preparation and loading conditions. Pharmacokinetics was evaluated following i.v. infusion in rabbits. RESULTS Freeze-thaw resulted in unilamellar liposome formation (180 nm) free of micelles. Higher DL was obtained when dialysis was used to remove the untrapped ammonium sulphate compared to ultracentrifuge. The pH and SBE-β-CD level in the loading solution played key roles in enhancing DL. High DL ASL-liposomes (8.9%w/w, drug-to-lipid mole ratio 26%) were obtained with some drug "bundles" in the liposomal cores and were stable in a 5% glucose solution for >80 days with minimal leakage (<2%). Surprisingly, following administration of ASL-liposomes prepared with or without SBE-β-CD, the half-lives were similar to the drug solution despite an increased area under the curve, indicating drug leakage from the carriers. CONCLUSIONS High liposomal DL was achieved with multiple strategies for a poorly-water soluble weak base. However, the liposomal permeability needed to be tailored to improve drug retention.
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Affiliation(s)
- Wenli Zhang
- School of Pharmacy, The University of Auckland, 1142, Auckland, New Zealand
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31
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Wilson MK, Baguley BC, Wall C, Jameson MB, Findlay MP. Review of high-dose intravenous vitamin C as an anticancer agent. Asia Pac J Clin Oncol 2014; 10:22-37. [PMID: 24571058 DOI: 10.1111/ajco.12173] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/25/2013] [Indexed: 12/26/2022]
Abstract
In the 1970s, Pauling and Cameron reported increased survival of patients with advanced cancer treated with high-dose intravenous (IV) vitamin C (L-ascorbate, ascorbic acid). These studies were criticized for their retrospective nature and lack of standardization of key prognostic factors including performance status. Subsequently, several well-designed randomized controlled trials failed to demonstrate a significant survival benefit, although these trials used high-dose oral vitamin C. Marked differences are now recognized in the pharmacokinetics of vitamin C with oral and IV administration, opening the issue of therapeutic efficacy to question. In vitro evidence suggests that vitamin C functions at low concentrations as an antioxidant but may have pro-oxidant activity at high concentrations. The mechanism of its pro-oxidant action is not fully understood, and both intra- and extracellular mechanisms that generate hydrogen peroxide have been proposed. It remains to be proven whether vitamin C-induced reactive oxygen species occur in vivo and, if so, whether this will translate to a clinical benefit. Current clinical evidence for a therapeutic effect of high-dose IV vitamin C is ambiguous, being based on case series. The interpretation and validation of these studies is hindered by limited correlation of plasma vitamin C concentrations with response. The methodology exists to determine if there is a role for high-dose IV vitamin C in the treatment of cancer, but the limited understanding of its pharmacodynamic properties makes this challenging. Currently, the use of high-dose IV vitamin C cannot be recommended outside of a clinical trial.
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Rewcastle GW, Flanagan JU, Giddens AC, Gamage SA, Tsang SKY, Kendall JD, Baguley BC, Buchanan CM, Matthews DJ, O'Farrell M, Jamieson SMF, Denny WA, Shepherd PR. Abstract 1644: Design and discovery of PWT33597 (VDC-597), a dual inhibitor of PI3-kinase alpha and mTOR. Cancer Res 2014. [DOI: 10.1158/1538-7445.am2014-1644] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Phosphoinositide-3-kinase (PI3K) is an important mediator of tumor cell growth, survival and proliferation. In particular, PI3K alpha is important for signaling downstream of receptor tyrosine kinases and is also frequently amplified or mutationally
activated in tumors, suggesting that selective inhibitors of this isoform may have therapeutic utility in the treatment of cancer. Downstream of PI3K, the mTOR kinase also plays a critical role in cellular growth and metabolism, and inhibitors of mTOR have demonstrated clinical benefit in several tumor types. We report here the design, discovery and characterization of PWT33597 (VDC-597), a dual inhibitor of PI3K alpha and mTOR, which entered human clinical trials in 2011. Starting with the known pan-Class I PI3-kinase inhibitor ZSTK474, we identified the methanesulfonylpiperazine analogue, 2-(difluoromethyl)-1-[4-[4-(methylsulfonyl)-1-piperazinyl]-6-(4-morpholinyl)-1,3,5-triazin-2-yl]-1H-benzimidazole as a promising lead compound with activity against both PI3K alpha (IC50 = 21 nM) and PI3K delta (IC50 = 18 nM). The addition of a methoxy group at the 4-position of the benzimidazole group led to a more selective inhibitor of PI3K alpha (IC50 = 6 nM versus 41 nM for PI3K delta), although with reduced solubility. A search for more soluble analogues identified SN 32976 as a selective inhibitor of PI3K alpha (IC50 = 28 nM) over both PI3K delta (IC50 = 287 nM) and mTOR (IC50 = 227 nM), with good aqueous solubility. SN 32976 displayed good oral bioavailability and was significantly more active than ZSTK474 against a U87 MG human tumor xenograft model in mice. A search for more metabolically stable analogues subsequently identified PWT33597, which maintained the selectivity for PI3K alpha (IC50 = 26 nM) over PI3K delta (IC50 = 291 nM) but now also displayed activity against mTOR in biochemical assays (IC50 = 21 nM). PWT33597 had good pharmacokinetic properties in multiple preclinical species, was not extensively metabolized in vivo and showed little potential for interaction with cytochrome P450 enzymes. Human clinical trials of PWT33597 were completed in 2012, and it is now undergoing further studies in veterinary cancers (as VDC-597).
Citation Format: Gordon W. Rewcastle, Jack U. Flanagan, Anna C. Giddens, Swarna A. Gamage, Sophia KY Tsang, Jackie D. Kendall, Bruce C. Baguley, Christina M. Buchanan, David J. Matthews, Marie O'Farrell, Stephen MF Jamieson, William A. Denny, Peter R. Shepherd. Design and discovery of PWT33597 (VDC-597), a dual inhibitor of PI3-kinase alpha and mTOR. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1644. doi:10.1158/1538-7445.AM2014-1644
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Leung EY, Kim JE, Askarian-Amiri M, Joseph WR, McKeage MJ, Baguley BC. Hormone Resistance in Two MCF-7 Breast Cancer Cell Lines is Associated with Reduced mTOR Signaling, Decreased Glycolysis, and Increased Sensitivity to Cytotoxic Drugs. Front Oncol 2014; 4:221. [PMID: 25232533 PMCID: PMC4153047 DOI: 10.3389/fonc.2014.00221] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 08/02/2014] [Indexed: 11/13/2022] Open
Abstract
The mTOR pathway is a key regulator of multiple cellular signaling pathways and is a potential target for therapy. We have previously developed two hormone-resistant sub-lines of the MCF-7 human breast cancer line, designated TamC3 and TamR3, which were characterized by reduced mTOR signaling, reduced cell volume, and resistance to mTOR inhibition. Here, we show that these lines exhibit increased sensitivity to carboplatin, oxaliplatin, 5-fluorouracil, camptothecin, doxorubicin, paclitaxel, docetaxel, and hydrogen peroxide. The mechanisms underlying these changes have not yet been characterized but may include a shift from glycolysis to mitochondrial respiration. If this phenotype is found in clinical hormone-resistant breast cancers, conventional cytotoxic therapy may be a preferred option for treatment.
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Affiliation(s)
- Euphemia Yee Leung
- Auckland Cancer Society Research Centre, University of Auckland , Auckland , New Zealand
| | - Ji Eun Kim
- Auckland Cancer Society Research Centre, University of Auckland , Auckland , New Zealand
| | - Marjan Askarian-Amiri
- Auckland Cancer Society Research Centre, University of Auckland , Auckland , New Zealand
| | - Wayne R Joseph
- Auckland Cancer Society Research Centre, University of Auckland , Auckland , New Zealand
| | - Mark J McKeage
- Auckland Cancer Society Research Centre, University of Auckland , Auckland , New Zealand
| | - Bruce C Baguley
- Auckland Cancer Society Research Centre, University of Auckland , Auckland , New Zealand
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Leung EY, Kim JE, Askarian-Amiri M, Rewcastle GW, Finlay GJ, Baguley BC. Relationships between signaling pathway usage and sensitivity to a pathway inhibitor: examination of trametinib responses in cultured breast cancer lines. PLoS One 2014; 9:e105792. [PMID: 25170609 PMCID: PMC4149495 DOI: 10.1371/journal.pone.0105792] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2014] [Accepted: 07/23/2014] [Indexed: 11/19/2022] Open
Abstract
Cellular signaling pathways involving mTOR, PI3K and ERK have dominated recent studies of breast cancer biology, and inhibitors of these pathways have formed a focus of numerous clinical trials. We have chosen trametinib, a drug targeting MEK in the ERK pathway, to address two questions. Firstly, does inhibition of a signaling pathway, as measured by protein phosphorylation, predict the antiproliferative activity of trametinib? Secondly, do inhibitors of the mTOR and PI3K pathways synergize with trametinib in their effects on cell proliferation? A panel of 30 human breast cancer cell lines was chosen to include lines that could be classified according to whether they were ER and PR positive, HER2 over-expressing, and “triple negative”. Everolimus (targeting mTOR), NVP-BEZ235 and GSK2126458 (both targeting PI3K/mTOR) were chosen for combination experiments. Inhibition of cell proliferation was measured by IC50 values and pathway utilization was measured by phosphorylation of signaling kinases. Overall, no correlation was found between trametinib IC50 values and inhibition of ERK signaling. Inhibition of ERK phosphorylation was observed at trametinib concentrations not affecting proliferation, and sensitivity of cell proliferation to trametinib was found in cell lines with low ERK phosphorylation. Evidence was found for synergy between trametinib and either everolimus, NVP-BEZ235 or GSK2126458, but this was cell line specific. The results have implications for the clinical application of PI3K/mTOR and MEK inhibitors.
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Affiliation(s)
- Euphemia Y. Leung
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
- * E-mail: (EYL); (BCB)
| | - Ji Eun Kim
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Marjan Askarian-Amiri
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Gordon W. Rewcastle
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Graeme J. Finlay
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Bruce C. Baguley
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
- * E-mail: (EYL); (BCB)
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See E, Zhang W, Liu J, Svirskis D, Baguley BC, Shaw JP, Wang G, Wu Z. Physicochemical characterization of asulacrine towards the development of an anticancer liposomal formulation via active drug loading: stability, solubility, lipophilicity and ionization. Int J Pharm 2014; 473:528-35. [PMID: 25079434 DOI: 10.1016/j.ijpharm.2014.07.033] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Revised: 06/10/2014] [Accepted: 07/24/2014] [Indexed: 11/29/2022]
Abstract
To facilitate the development of a liposomal formulation for cancer therapy, the physicochemical properties of asulacrine (ASL), an anticancer drug candidate, were characterized. Nano-liposomes were prepared by thin-film hydration in conjugation with active drug loading using ammonium sulphate and post-insertion with Poloxamer 188. A stability-indicating HPLC assay with diode array detection was developed for the determination of ASL concentrations. The U-shaped pH-solubility profile in aqueous solutions, with a lowest solubility at pH 7.4 (0.843 μg/mL), indicated that ASL is an ampholyte, and dilution or neutralization of acidic drug solutions used in clinical trials with physiological fluids may cause drug precipitation. The basic pKa value measured by absorbance spectroscopy was 6.72. The logD value at pH 3.8 was 1.15 which increased to 3.24 as pH increased to 7.4. ASL was found to be the most stable in acidic conditions and degraded most rapidly in alkaline conditions. An extra-liposomal pH of 5.6 during drug loading was found to be optimal to achieve the highest drug loading (DL) of 4.76% and entrapment efficiency (EE) of 99.9%. At this pH, >90% of ASL was ionized conferring high drug solubility (1mg/mL) and acted as a reservoir of unionized ASL to be transported into liposomal cores. As a suspension the optimized liposomes showed great physicochemical stability for five months at 4°C. In summary, the obtained physicochemical parameters provided insightful information useful to maximise DL into the liposomes, and explain a tendency of drug precipitation of pH-solubilized formulations following intravenous infusion.
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Affiliation(s)
- Esther See
- School of Pharmacy, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 114, New Zealand
| | - Wenli Zhang
- School of Pharmacy, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 114, New Zealand
| | - Jianping Liu
- China Pharmaceutical University, Nanjing 210009, PR China
| | - Darren Svirskis
- School of Pharmacy, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 114, New Zealand
| | - Bruce C Baguley
- Auckland Cancer Society Research Centre, University of Auckland, New Zealand
| | - John P Shaw
- School of Pharmacy, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 114, New Zealand
| | - Guangji Wang
- China Pharmaceutical University, Nanjing 210009, PR China
| | - Zimei Wu
- School of Pharmacy, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland 114, New Zealand.
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Askarian-Amiri ME, Seyfoddin V, Smart CE, Wang J, Kim JE, Hansji H, Baguley BC, Finlay GJ, Leung EY. Emerging role of long non-coding RNA SOX2OT in SOX2 regulation in breast cancer. PLoS One 2014; 9:e102140. [PMID: 25006803 PMCID: PMC4090206 DOI: 10.1371/journal.pone.0102140] [Citation(s) in RCA: 100] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 06/13/2014] [Indexed: 02/02/2023] Open
Abstract
The transcription factor SOX2 is essential for maintaining pluripotency in a variety of stem cells. It has important functions during embryonic development, is involved in cancer stem cell maintenance, and is often deregulated in cancer. The mechanism of SOX2 regulation has yet to be clarified, but the SOX2 gene lies in an intron of a long multi-exon non-coding RNA called SOX2 overlapping transcript (SOX2OT). Here, we show that the expression of SOX2 and SOX2OT is concordant in breast cancer, differentially expressed in estrogen receptor positive and negative breast cancer samples and that both are up-regulated in suspension culture conditions that favor growth of stem cell phenotypes. Importantly, ectopic expression of SOX2OT led to an almost 20-fold increase in SOX2 expression, together with a reduced proliferation and increased breast cancer cell anchorage-independent growth. We propose that SOX2OT plays a key role in the induction and/or maintenance of SOX2 expression in breast cancer.
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Affiliation(s)
| | - Vahid Seyfoddin
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Chanel E. Smart
- University of Queensland Centre for Clinical Research, Royal Brisbane & Women's Hospital Campus, Herston, Queensland, Australia
| | - Jingli Wang
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Ji Eun Kim
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Herah Hansji
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Bruce C. Baguley
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Graeme J. Finlay
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
- * E-mail: (GJF); (EYL)
| | - Euphemia Y. Leung
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
- * E-mail: (GJF); (EYL)
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Macaulay EC, Roberts HE, Cheng X, Jeffs AR, Baguley BC, Morison IM. Retrotransposon hypomethylation in melanoma and expression of a placenta-specific gene. PLoS One 2014; 9:e95840. [PMID: 24759919 PMCID: PMC3997481 DOI: 10.1371/journal.pone.0095840] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Accepted: 03/31/2014] [Indexed: 11/18/2022] Open
Abstract
In the human placenta, DNA hypomethylation permits the expression of retrotransposon-derived genes that are normally silenced by methylation in somatic tissues. We previously identified hypomethylation of a retrotransposon-derived transcript of the voltage-gated potassium channel gene KCNH5 that is expressed only in human placenta. However, an RNA sequence from this placental-specific transcript has been reported in melanoma. This study examined the promoter methylation and expression of the retrotransposon-derived KCNH5 transcript in 25 melanoma cell lines to determine whether the acquisition of 'placental' epigenetic marks is a feature of melanoma. Methylation and gene expression analysis revealed hypomethylation of this retrotransposon in melanoma cell lines, particularly in those samples that express the placental KCNH5 transcript. Therefore we propose that hypomethylation of the placental-specific KCNH5 promoter is frequently associated with KCNH5 expression in melanoma cells. Our findings show that melanoma can develop hypomethylation of a retrotransposon-derived gene; a characteristic notably shared with the normal placenta.
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Affiliation(s)
- Erin C. Macaulay
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
- Gravida: National Centre for Growth and Development, Auckland, New Zealand
- * E-mail:
| | - Hester E. Roberts
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
- Gravida: National Centre for Growth and Development, Auckland, New Zealand
| | - Xi Cheng
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Aaron R. Jeffs
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Bruce C. Baguley
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Ian M. Morison
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
- Gravida: National Centre for Growth and Development, Auckland, New Zealand
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Hung N, Chen YJ, Taha A, Olivecrona M, Boet R, Wiles A, Warr T, Shaw A, Eiholzer R, Baguley BC, Eccles MR, Braithwaite AW, Macfarlane M, Royds JA, Slatter T. Increased paired box transcription factor 8 has a survival function in glioma. BMC Cancer 2014; 14:159. [PMID: 24602166 PMCID: PMC4015841 DOI: 10.1186/1471-2407-14-159] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Accepted: 02/28/2014] [Indexed: 11/10/2022] Open
Abstract
Background The molecular basis to overcome therapeutic resistance to treat glioblastoma remains unclear. The anti-apoptotic b cell lymphoma 2 (BCL2) gene is associated with treatment resistance, and is transactivated by the paired box transcription factor 8 (PAX8). In earlier studies, we demonstrated that increased PAX8 expression in glioma cell lines was associated with the expression of telomerase. In this current study, we more extensively explored a role for PAX8 in gliomagenesis. Methods PAX8 expression was measured in 156 gliomas including telomerase-negative tumours, those with the alternative lengthening of telomeres (ALT) mechanism or with a non-defined telomere maintenance mechanism (NDTMM), using immunohistochemistry and quantitative PCR. We also tested the affect of PAX8 knockdown using siRNA in cell lines on cell survival and BCL2 expression. Results Seventy-two percent of glioblastomas were PAX8-positive (80% telomerase, 73% NDTMM, and 44% ALT). The majority of the low-grade gliomas and normal brain cells were PAX8-negative. The suppression of PAX8 was associated with a reduction in both cell growth and BCL2, suggesting that a reduction in PAX8 expression would sensitise tumours to cell death. Conclusions PAX8 is increased in the majority of glioblastomas and promoted cell survival. Because PAX8 is absent in normal brain tissue, it may be a promising therapeutic target pathway for treating aggressive gliomas.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | - Tania Slatter
- Department of Pathology, University of Otago, Dunedin, New Zealand.
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D'mello SAN, Flanagan JU, Green TN, Leung EY, Askarian-Amiri ME, Joseph WR, McCrystal MR, Isaacs RJ, Shaw JHF, Furneaux CE, During MJ, Finlay GJ, Baguley BC, Kalev-Zylinska ML. Evidence That GRIN2A Mutations in Melanoma Correlate with Decreased Survival. Front Oncol 2014; 3:333. [PMID: 24455489 PMCID: PMC3888952 DOI: 10.3389/fonc.2013.00333] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2013] [Accepted: 12/30/2013] [Indexed: 12/17/2022] Open
Abstract
Previous whole-exome sequencing has demonstrated that melanoma tumors harbor mutations in the GRIN2A gene. GRIN2A encodes the regulatory GluN2A subunit of the glutamate-gated N-methyl-d-aspartate receptor (NMDAR), involvement of which in melanoma remains undefined. Here, we sequenced coding exons of GRIN2A in 19 low-passage melanoma cell lines derived from patients with metastatic melanoma. Potential mutation impact was evaluated in silico, including within the GluN2A crystal structure, and clinical correlations were sought. We found that of 19 metastatic melanoma tumors, four (21%) carried five missense mutations in the evolutionarily conserved domains of GRIN2A; two were previously reported. Melanoma cells that carried these mutations were treatment-naïve. Sorting intolerant from tolerant analysis predicted that S349F, G762E, and P1132L would disrupt protein function. When modeled into the crystal structure of GluN2A, G762E was seen to potentially alter GluN1-GluN2A interactions and ligand binding, implying disruption to NMDAR functionality. Patients whose tumors carried non-synonymous GRIN2A mutations had faster disease progression and shorter overall survival (P < 0.05). This was in contrast to the BRAF V600E mutation, found in 58% of tumors but showing no correlation with clinical outcome (P = 0.963). Although numbers of patients in this study are small, and firm conclusions about the association between GRIN2A mutations and poor clinical outcome cannot be drawn, our results highlight the high prevalence of GRIN2A mutations in metastatic melanoma and suggest for the first time that mutated NMDARs impact melanoma progression.
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Affiliation(s)
- Stacey Ann N D'mello
- Department of Molecular Medicine and Pathology, School of Medical Sciences, University of Auckland , Auckland , New Zealand
| | - Jack U Flanagan
- Auckland Cancer Society Research Centre, University of Auckland , Auckland , New Zealand ; Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland , Auckland , New Zealand
| | - Taryn N Green
- Department of Molecular Medicine and Pathology, School of Medical Sciences, University of Auckland , Auckland , New Zealand
| | - Euphemia Y Leung
- Auckland Cancer Society Research Centre, University of Auckland , Auckland , New Zealand
| | | | - Wayne R Joseph
- Auckland Cancer Society Research Centre, University of Auckland , Auckland , New Zealand
| | - Michael R McCrystal
- Department of Clinical Oncology, Auckland District Health Board , Auckland , New Zealand ; Canopy Cancer Care, Mercy Hospital , Auckland , New Zealand
| | - Richard J Isaacs
- Regional Cancer Treatment Service, Palmerston North Public Hospital , Palmerston North , New Zealand
| | | | | | - Matthew J During
- Department of Molecular Virology, Immunology and Medical Genetics, Neuroscience and Neurological Surgery, Ohio State University , Columbus, OH , USA ; Centre for Brain Research, University of Auckland , Auckland , New Zealand
| | - Graeme J Finlay
- Auckland Cancer Society Research Centre, University of Auckland , Auckland , New Zealand
| | - Bruce C Baguley
- Auckland Cancer Society Research Centre, University of Auckland , Auckland , New Zealand
| | - Maggie L Kalev-Zylinska
- Department of Molecular Medicine and Pathology, School of Medical Sciences, University of Auckland , Auckland , New Zealand ; LabPlus Haematology, Auckland District Health Board , Auckland , New Zealand
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Kendall JD, Marshall AJ, Giddens AC, Tsang KY, Boyd M, Frédérick R, Lill CL, Lee WJ, Kolekar S, Chao M, Malik A, Yu S, Chaussade C, Buchanan CM, Rewcastle GW, Baguley BC, Flanagan JU, Denny WA, Shepherd PR. Novel pyrazolo[1,5-a]pyridines as PI3K inhibitors: variation of the central linker group. Med Chem Commun 2014. [DOI: 10.1039/c3md00221g] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Lukka PB, Chen YY, Finlay GJ, Joseph WR, Richardson E, Paxton JW, Baguley BC. Tumour tissue selectivity in the uptake and retention of SN 28049, a new topoisomerase II-directed anticancer agent. Cancer Chemother Pharmacol 2013; 72:1013-22. [PMID: 24036845 DOI: 10.1007/s00280-013-2280-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Accepted: 08/27/2013] [Indexed: 01/03/2023]
Abstract
PURPOSE A variety of anticancer drugs, including doxorubicin and mitoxantrone, have structures in which a DNA-intercalating chromophore is linked to a positively charged side chain. These drugs generally inhibit tumour growth and survival by poisoning the enzyme DNA topoisomerase II. SN 28049, a benzonaphthyridine derivative with these properties, has curative activity against the Colon 38 tumour in mice. Previous pharmacokinetic studies have demonstrated tumour-selective retention with approximately 20-fold higher area under the concentration-time curve (AUC) for tumour tissue as compared to normal tissues. We have investigated here whether such retention is tumour specific. METHODS Plasma and tissue pharmacokinetics were assessed in the murine Lewis lung (LL3) tumour in C57 BL/6 mice and in xenografts of the NZM4, NZM10 and NZM52 human melanoma lines in Balb/c Rag-1 immunodeficient mice. The in vitro cellular localisation of SN 28049 in murine and human cell lines was studied by confocal fluorescence microscopy. RESULTS A 260-fold variation, from 8.9 μM h (NZM4) to 2,334 μM h (Colon 38), was found among the different tumours. Only small variations were observed in the corresponding plasma AUC (2.9-5 μM h). Moreover, in vivo activity, as measured by tumour growth delay, varied from 1 day (NZM4) to curative (Colon 38), consistent with the tumour pharmacokinetic data. In cultured cell lines, SN 28049 was found in cytoplasmic bodies, suggesting that drug sequestration could contribute to tumour pharmacokinetics. CONCLUSION SN 28049 shows dramatic differences in both tumour AUC and antitumour activity against different tumours. These differences point to the presence of a tumour-specific uptake and retention mechanism.
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Affiliation(s)
- Pradeep B Lukka
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand
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Eccles MR, He S, Ahn A, Slobbe LJ, Jeffs AR, Yoon HS, Baguley BC. MITF and PAX3 Play Distinct Roles in Melanoma Cell Migration; Outline of a "Genetic Switch" Theory Involving MITF and PAX3 in Proliferative and Invasive Phenotypes of Melanoma. Front Oncol 2013; 3:229. [PMID: 24062982 PMCID: PMC3769631 DOI: 10.3389/fonc.2013.00229] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Accepted: 08/21/2013] [Indexed: 11/13/2022] Open
Abstract
Melanoma is a very aggressive neoplasm with a propensity to undergo progression and invasion early in its evolution. The molecular pathways underpinning invasion in melanoma are now just beginning to be elucidated, but a clear understanding of the transition from non-invasive to invasive melanoma cells remains elusive. Microphthalmia-associated transcription factor (MITF), is thought to be a central player in melanoma biology, and it controls many aspects of the phenotypic expression of the melanocytic lineage. However, recently the paired box transcription factor PAX3 was shown to transcriptionally activate POU3F2/BRN2, leading to direct repression of MITF expression. Here we present a theory to explain melanoma phenotype switching and discuss the predictions that this theory makes. One prediction is that independent and opposing roles for MITF and PAX3 in melanoma would be expected, and we present empirical evidence supporting this: in melanoma tissues PAX3 expression occurs independently of MITF, and PAX3 does not play a key role in melanoma cell proliferation. Furthermore, we show that knockdown of PAX3 inhibits cell migration in a group of "lower MITF" melanoma cell lines, while knockdown of MITF promotes cell migration in a complementary "higher MITF" group of melanoma cell lines. Moreover, the morphological effects of knocking down PAX3 versus MITF in melanoma cells were found to differ. While these data support the notion of independent roles for MITF and PAX3, additional experiments are required to provide robust examination of the proposed genetic switch theory. Only upon clear delineation of the mechanisms associated with progression and invasion of melanoma cells will successful treatments for invasive melanoma be developed.
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Affiliation(s)
- Michael R Eccles
- Department of Pathology, University of Otago , Dunedin , New Zealand
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Awasthi A, Woolley AG, Lecomte FJ, Hung N, Baguley BC, Wilbanks SM, Jeffs AR, Tyndall JDA. Variable Expression of GLIPR1 Correlates with Invasive Potential in Melanoma Cells. Front Oncol 2013; 3:225. [PMID: 24010123 PMCID: PMC3757444 DOI: 10.3389/fonc.2013.00225] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Accepted: 08/16/2013] [Indexed: 12/11/2022] Open
Abstract
GLI pathogenesis-related 1 (GLIPR1) was previously identified as an epigenetically regulated tumor suppressor in prostate cancer and, conversely, an oncoprotein in glioma. More recently, GLIPR1 was shown to be differentially expressed in other cancers including ovarian, acute myeloid leukemia, and Wilms' tumor. Here we investigated GLIPR1 expression in metastatic melanoma cell lines and tissue. GLIPR1 was variably expressed in metastatic melanoma cells, and transcript levels correlated with degree of GLIPR1 promoter methylation in vitro. Elevated GLIPR1 levels were correlated with increased invasive potential, and siRNA-mediated knockdown of GLIPR1 expression resulted in reduced cell migration and proliferation in vitro. Immunohistochemical studies of melanoma tissue microarrays showed moderate to high staining for GLIPR1 in 50% of specimens analyzed. GLIPR1 staining was observed in normal skin in merocrine sweat glands, sebaceous glands, and hair follicles within the dermis.
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Affiliation(s)
- Anshul Awasthi
- School of Pharmacy, University of Otago , Dunedin , New Zealand ; Department of Pathology, Dunedin School of Medicine, University of Otago , Dunedin , New Zealand ; Department of Biochemistry, Otago School of Medical Sciences, University of Otago , Dunedin , New Zealand
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Kim JE, Leung E, Baguley BC, Finlay GJ. Heterogeneity of expression of epithelial-mesenchymal transition markers in melanocytes and melanoma cell lines. Front Genet 2013; 4:97. [PMID: 23755070 PMCID: PMC3668138 DOI: 10.3389/fgene.2013.00097] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Accepted: 05/14/2013] [Indexed: 11/13/2022] Open
Abstract
The epithelial–mesenchymal transition (EMT) describes a reversible switch from an epithelial-like to a mesenchymal-like phenotype. It is essential for the development of the normal epithelium and also contributes to the invasive properties of carcinomas. At the molecular level, the EMT transition is characterized by a series of coordinated changes including downregulation of the junctional protein E-cadherin (CDH1), up-regulation of transcriptional repressors of E-cadherin such as Snail (SNAI1) and Slug (SNAI2), and up-regulation of N-cadherin. We wished to determine whether cultured normal melanocytes and melanoma cell lines, which are derived from the neural crest, showed signs of a similarly coordinated phenotypic switch. We investigated normal melanocytes and 25 cell lines derived from New Zealand patients with metastatic melanoma. Most lines had been previously genotyped for common mutations such as BRAF, NRAS, PIK3CA (phosphatidylinositol-3-kinase), TP53 (p53), and CDKN2A (p16). Expression of E-cadherin, N-cadherin, microphthalmia-associated transcription factor (MITF), Snail, Slug, Axl, p53, and Hdm2 was compared by western blotting. Normal melanocytes expressed each of these proteins except for Snail, while normal melanocytes and almost every melanoma line expressed Slug. Expression of individual markers among different melanoma lines varied from high to low or undetectable. Quantitation of western blots showed that expression of MITF-M, the melanocyte-specific isoform of MITF, was positively related to that of E-cadherin but inversely related to that of N-cadherin and Axl. There was also no apparent relationship between expression of any particular marker and the presence of BRAF, NRAS, PIK3CA, TP53, or CDKN2A mutations. The results suggest that melanomas do not show the classical epithelial and mesenchymal phenotypes but rather display either high E-cadherin/high MITF-M expression on one hand, or high N-cadherin/high Axl expression on the other. These may correspond to differentiated and invasive phenotypes in vivo.
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Affiliation(s)
- Ji Eun Kim
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland Auckland, New Zealand
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Abstract
The Hippo signaling pathway comprises a series of cytoplasmic tumor suppressor proteins including Merlin and the Lats1/2 and MST1/2 kinases, and is thought to play a critical role in determining the sizes of organs and tissues. The Hippo pathway is regulated upstream by extracellular mechanosensory signaling arising from cell shape and polarity, as well as by a variety of extracellular signaling molecules. When active, the pathway maintains the transcriptional activators Yes-associated protein (YAP) and TAZ in phosphorylated forms in the cytoplasm, preventing cell proliferation. When the Hippo pathway is inactivated, YAP and TAZ are translocated to the nucleus and induce the expression of a variety of proteins concerned with entry into the cell division cycle, such as cyclin D1 and Fox M1, as well as the inhibition of apoptosis. The failure of the Hippo pathway has been implicated in the development of many different types of cancer but there is limited information available as to its involvement in melanoma. We hypothesize here firstly that the Hippo pathway is involved in maintaining density of cutaneous melanocytes on the basement membrane at the junction of the epidermis and the dermis, and secondly, that its function is disturbed in melanoma. We have analyzed a series of 23 low passage human melanoma lines as well as cultured normal melanoma, and find that melanocytes, as well as all melanoma cell lines examined express TAZ. Melanocytes and most melanoma lines also express YAP. E-cadherin, an upstream regulator of the Hippo pathway, and Axl, a receptor tyrosine kinase regulated by the Hippo pathway, are expressed in melanocytes and in several melanoma cell lines. These observations, together with published evidence for the presence of Merlin, Lats1/2, and MST1/2 in melanocytes and melanoma cells, support the hypothesis that the Hippo pathway is an important component of melanocyte and melanoma behavior.
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Affiliation(s)
- Ji Eun Kim
- Faculty of Medical and Health Sciences, Auckland Cancer Society Research Centre, The University of Auckland Auckland, New Zealand
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Stones CJ, Kim JE, Joseph WR, Leung E, Marshall ES, Finlay GJ, Shelling AN, Baguley BC. Comparison of responses of human melanoma cell lines to MEK and BRAF inhibitors. Front Genet 2013; 4:66. [PMID: 23658559 PMCID: PMC3647113 DOI: 10.3389/fgene.2013.00066] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Accepted: 04/09/2013] [Indexed: 11/13/2022] Open
Abstract
The NRAS and BRAF genes are frequently mutated in melanoma, suggesting that the NRAS-BRAF-MEK-ERK signaling pathway is an important target for therapy. Two classes of drugs, one targeting activated BRAF and one targeting MEK, are currently undergoing clinical evaluation. We have analysed the NRAS and BRAF mutational status of a series of 44 early passage lines developed from New Zealand patients with metastatic melanoma. 41% of the lines analysed had BRAF mutations, 23% had NRAS mutations, and 36% had neither. We then determined IC50 values (drug concentrations for 50% growth inhibition) for CI-1040, a commonly used inhibitor of MEK kinase; trametinib, a clinical agent targeting MEK kinase; and vemurafenib, an inhibitor of mutant BRAF kinase. Cell lines with activating BRAF mutations were significantly more sensitive to vemurafenib than lines with NRAS mutations or lines lacking either mutation (p < 0.001). IC50 values for CI-1040 and trametinib were strongly correlated (r = 0.98) with trametinib showing ~100-fold greater potency. Cell lines sensitive to vemurafenib were also sensitive to CI-1040 and trametinib, but there was no relationship between IC50 values and NRAS mutation status. A small number of lines lacking a BRAF mutation were sensitive to CI-1040 but resistant to vemurafenib. We used western blotting to investigate the effect on ERK phosphorylation of CI-1040 in four lines, of vemurafenib in two lines and of trametinib in two lines. The results support the view that MEK inhibitors might be combined with BRAF inhibitors in the treatment of melanomas with activated BRAF. The high sensitivity to trametinib of some lines with wildtype BRAF status also suggests that MEK inhibitors could have a therapeutic effect against some melanomas as single agents.
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Affiliation(s)
- Clare J Stones
- Department of Obstetrics and Gynaecology, The University of Auckland Auckland, New Zealand ; Auckland Cancer Society Research Centre, The University of Auckland Auckland, New Zealand
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Abstract
BACKGROUND Human tumour cell lines have played a major role in anticancer drug discovery, but cell lines may model only some aspects of tumour behaviour in cancer patients. Growing evidence supports a theory that stem cells with self-renewing properties sustain tumours. OBJECTIVE This review considers the extent to which a deeper understanding of the origin and properties of tumour cell lines might lead to new strategies for anticancer drug discovery. METHODS Recent literature on normal and tumour stem cells is reviewed and placed in the context of a discussion on the derivation and properties of tumour cell lines. RESULTS/CONCLUSION Early-passage cell lines may model the more rapidly proliferating cells in human tumours and, thus, retain some of the properties of tumour stem cells. The effects of anticancer drugs on cell lines should be considered not only with regards to the induction of apoptosis, but also to the induction of senescence or other pathways that lead to host immune and inflammatory responses.
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Affiliation(s)
- Bruce C Baguley
- Professor and Co-Director The University of Auckland, Auckland Cancer Society Research Centre, Auckland 1142, New Zealand +64 9 3737599 ; +649 3737502 ;
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Lukka PB, Paxton JW, Kestell P, Baguley BC. Comparison of a homologous series of benzonaphthyridine anti-cancer agents in mice: divergence between tumour and plasma pharmacokinetics. Cancer Chemother Pharmacol 2012; 70:151-60. [DOI: 10.1007/s00280-012-1892-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Accepted: 05/09/2012] [Indexed: 10/28/2022]
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Kim JE, Stones C, Joseph WR, Leung E, Finlay GJ, Shelling AN, Phillips WA, Shepherd PR, Baguley BC. Comparison of growth factor signalling pathway utilisation in cultured normal melanocytes and melanoma cell lines. BMC Cancer 2012; 12:141. [PMID: 22475322 PMCID: PMC3352269 DOI: 10.1186/1471-2407-12-141] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Accepted: 04/04/2012] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND The phosphatidylinositol-3-kinase (PI3K-PKB), mitogen activated protein kinase (MEK-ERK) and the mammalian target of rapamycin (mTOR- p70S6K), are thought to regulate many aspects of tumour cell proliferation and survival. We have examined the utilisation of these three signalling pathways in a number of cell lines derived from patients with metastatic malignant melanoma of known PIK3CA, PTEN, NRAS and BRAF mutational status. METHODS Western blotting was used to compare the phosphorylation status of components of the PI3K-PKB, MEK-ERK and mTOR-p70S6K signalling pathways, as indices of pathway utilisation. RESULTS Normal melanocytes could not be distinguished from melanoma cells on the basis of pathway utilisation when grown in the presence of serum, but could be distinguished upon serum starvation, where signalling protein phosphorylation was generally abrogated. Surprisingly, the differential utilisation of individual pathways was not consistently associated with the presence of an oncogenic or tumour suppressor mutation of genes in these pathways. CONCLUSION Utilisation of the PI3K-PKB, MEK-ERK and mTOR-p70S6K signalling pathways in melanoma, as determined by phosphorylation of signalling components, varies widely across a series of cell lines, and does not directly reflect mutation of genes coding these components. The main difference between cultured normal melanocytes and melanoma cells is not the pathway utilisation itself, but rather in the serum dependence of pathway utilisation.
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Affiliation(s)
- Ji Eun Kim
- Auckland Cancer Society Research Centre, The University of Auckland, Auckland, New Zealand
- Auckland Cancer Society Research Centre, Private Bag 92019, The University of Auckland, Auckland, New Zealand
| | - Clare Stones
- Auckland Cancer Society Research Centre, The University of Auckland, Auckland, New Zealand
- Department of Molecular Medicine and Pathology, The University of Auckland, Auckland, New Zealand
| | - Wayne R Joseph
- Auckland Cancer Society Research Centre, The University of Auckland, Auckland, New Zealand
| | - Euphemia Leung
- Auckland Cancer Society Research Centre, The University of Auckland, Auckland, New Zealand
| | - Graeme J Finlay
- Auckland Cancer Society Research Centre, The University of Auckland, Auckland, New Zealand
- Department of Molecular Medicine and Pathology, The University of Auckland, Auckland, New Zealand
| | - Andrew N Shelling
- Department of Obstetrics and Gynaecology, The University of Auckland, Auckland, New Zealand
| | - Wayne A Phillips
- Department of Surgery, Surgical Oncology Research Laboratory, Peter MacCallum Cancer Centre and University of Melbourne, St. Vincent's Hospital, Melbourne, VIC, Australia
| | - Peter R Shepherd
- Department of Molecular Medicine and Pathology, The University of Auckland, Auckland, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Auckland, New Zealand
| | - Bruce C Baguley
- Auckland Cancer Society Research Centre, The University of Auckland, Auckland, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Auckland, New Zealand
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Royds JA, Al Nadaf S, Wiles AK, Chen YJ, Ahn A, Shaw A, Bowie S, Lam F, Baguley BC, Braithwaite AW, MacFarlane MR, Hung NA, Slatter TL. The CDKN2A G500 allele is more frequent in GBM patients with no defined telomere maintenance mechanism tumors and is associated with poorer survival. PLoS One 2011; 6:e26737. [PMID: 22046342 PMCID: PMC3202568 DOI: 10.1371/journal.pone.0026737] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2011] [Accepted: 10/03/2011] [Indexed: 02/04/2023] Open
Abstract
Prognostic markers for glioblastoma multiforme (GBM) are important for patient management. Recent advances have identified prognostic markers for GBMs that use telomerase or the alternative lengthening of telomeres (ALT) mechanism for telomere maintenance. Approximately 40% of GBMs have no defined telomere maintenance mechanism (NDTMM), with a mixed survival for affected individuals. This study examined genetic variants in the cyclin-dependent kinase inhibitor 2A (CDKN2A) gene that encodes the p16INK4a and p14ARF tumor suppressors, and the isocitrate dehydrogenase 1 (IDH1) gene as potential markers of survival for 40 individuals with NDTMM GBMs (telomerase negative and ALT negative by standard assays), 50 individuals with telomerase, and 17 individuals with ALT positive tumors. The analysis of CDKN2A showed NDTMM GBMs had an increased minor allele frequency for the C500G (rs11515) polymorphism compared to those with telomerase and ALT positive GBMs (p = 0.002). Patients with the G500 allele had reduced survival that was independent of age, extent of surgery, and treatment. In the NDTMM group G500 allele carriers had increased loss of CDKN2A gene dosage compared to C500 homozygotes. An analysis of IDH1 mutations showed the R132H mutation was associated with ALT positive tumors, and was largely absent in NDTMM and telomerase positive tumors. In the ALT positive tumors cohort, IDH1 mutations were associated with a younger age for the affected individual. In conclusion, the G500 CDKN2A allele was associated with NDTMM GBMs from older individuals with poorer survival. Mutations in IDH1 were not associated with NDTMM GBMs, and instead were a marker for ALT positive tumors in younger individuals.
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Affiliation(s)
- Janice A. Royds
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Shafagh Al Nadaf
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Anna K. Wiles
- Department of Medicine, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Yu-Jen Chen
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Antonio Ahn
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Alisha Shaw
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Sara Bowie
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | | | - Bruce C. Baguley
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Antony W. Braithwaite
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
- Children's Research Institute, University of Sydney, Westmead, Australia
| | | | - Noelyn A. Hung
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Tania L. Slatter
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
- * E-mail:
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