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Blocking EZH2 methylation transferase activity by GSK126 decreases stem cell-like myeloma cells. Oncotarget 2018; 8:3396-3411. [PMID: 27926488 PMCID: PMC5356890 DOI: 10.18632/oncotarget.13773] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 11/21/2016] [Indexed: 01/14/2023] Open
Abstract
EZH2 is a critical epigenetic regulator that is deregulated in various types of cancers including multiple myeloma (MM). In the present study, we hypothesized that targeting EZH2 might induce apoptosis in myeloma cells including stem cell-like cells (CSCs). We investigated the effect of EZH2 inhibition on MM cells using a potent inhibitor (GSK126). The results showed that GSK126 effectively abrogated the methylated histone 3 (H3K27me3) level in MM.1S and LP1 cells, and inhibited the number of live cells and colony formation in soft agar of six MM cell lines. GSK126 induced massive apoptosis in MM.1S, LP1 and RPMI8226 cells. Progressive release of mitochondrial cytochrome c and AIF into the cytosol was detected in GSK126-treated MM cells. GSK126 treatment elicited caspase-3-dependent MCL-1 cleavage with accumulation of proapoptotic truncated MCL-1. These results suggested that GSK126 triggers the intrinsic mitochondrial apoptosis pathway. Enhanced apoptosis was observed in the combination of GSK126 with bortezomib. Using ALDH and side population (SP) assays to characterize CSCs, we found that GSK126 eliminated the stem-like myeloma cells by blocking the Wnt/β-catenin pathway. The in vivo anti-tumor effect of GSK126 was confirmed by using RPMI8226 cells in a xenograft mouse model. In conclusion, our findings suggest that EZH2 inactivation by GSK126 is effective in killing MM cells and CSCs as a single agent or in combination with bortezomib. Clinical trial of GSK126 in patients with MM may be warranted.
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102
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Xu F, Zhu Y, Lu Y, Yu Z, Zhong J, Li Y, Pan J. Anthelmintic pyrvinium pamoate blocks Wnt/β-catenin and induces apoptosis in multiple myeloma cells. Oncol Lett 2018; 15:5871-5878. [PMID: 29552217 DOI: 10.3892/ol.2018.8006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 12/21/2017] [Indexed: 01/12/2023] Open
Abstract
Multiple myeloma (MM) is a malignancy of the bone marrow. The median survival time of patients with MM is only 5 years, with patients frequently experiencing relapse. Currently, there is no effective therapy for recurrent MM. The results of the present study indicated that pyrvinium pamoate (PP), a US Food and Drug Administration-approved oral anthelmintic drug, exhibited potent antitumor activity in MM cells in vitro. It is demonstrated that PP inhibited MM cell proliferation and mediated apoptosis. Notably, PP markedly promoted the degradation of β-catenin and abrogated its phosphorylation. PP triggered apoptosis in MM cells by inducing the release of cytochrome c and downregulating the expression of myeloid leukemia cell differentiation protein. In addition, PP effectively induced cell death in primary MM cells. In conclusion, PP may be a promising agent for the clinical treatment of MM.
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Affiliation(s)
- Fang Xu
- Jinan University Institute of Tumor Pharmacology, College of Pharmacy, Guangzhou, Guangdong 510632, P.R. China
| | - Yingjie Zhu
- Jinan University Institute of Tumor Pharmacology, College of Pharmacy, Guangzhou, Guangdong 510632, P.R. China
| | - Yuhong Lu
- Department of Hematology, First Affiliated Hospital, Jinan University, Guangzhou, Guangdong 510632, P.R. China
| | - Zhi Yu
- Department of Hematology, First Affiliated Hospital, Jinan University, Guangzhou, Guangdong 510632, P.R. China
| | - Jun Zhong
- Department of Hematology, First Affiliated Hospital, Jinan University, Guangzhou, Guangdong 510632, P.R. China
| | - Yangqiu Li
- Department of Hematology, First Affiliated Hospital, Jinan University, Guangzhou, Guangdong 510632, P.R. China
| | - Jingxuan Pan
- Jinan University Institute of Tumor Pharmacology, College of Pharmacy, Guangzhou, Guangdong 510632, P.R. China
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103
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Anthelmintic niclosamide suppresses transcription of BCR-ABL fusion oncogene via disabling Sp1 and induces apoptosis in imatinib-resistant CML cells harboring T315I mutant. Cell Death Dis 2018; 9:68. [PMID: 29358661 PMCID: PMC5833368 DOI: 10.1038/s41419-017-0075-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 09/13/2017] [Accepted: 09/25/2017] [Indexed: 12/12/2022]
Abstract
Tyrosine kinase BCR-ABL fusion protein is the driver in patients with chronic myeloid leukemia (CML). The gate-keeper mutation T315I is the most challenging mutant due to its resistance to most tyrosine kinase inhibitors (TKIs). The third generation TKI ponatinib is the only effective TKI to treat CML patients harboring T315I-BCR-ABL mutation, but with high rate of major arterial thrombotic events. Alternative strategies to specifically target T315I-BCR-ABL are needed for the treatment of CML patients harboring such a mutation. Given that Sp1 is a fundamental transcriptional factor to positively regulate WT-BCR-ABL fusion oncogene, the purpose of this investigation was aimed at evaluating the anti-tumor activity and the underlying mechanism in terms of Sp1 regulational effect on the transcription of T315I-BCR-ABL fusion oncogene. Like in WT-BCR-ABL, we identified enrichment of Sp1 on the promoter of T315I-BCR-ABL fusion gene. Treatment of WT- and T315I-BCR-ABL-expressing CML cells by niclosamide diminished such an enrichment of Sp1, and decreased WT- and T315I-BCR-ABL transcription and its downstream signaling molecules such as STAT5 and Akt. Further, niclosamide significantly inhibited the proliferation and induced apoptosis through intrinsic pathway. The in vivo efficacy validation of p-niclosamide, a water soluble derivative of niclosamide, showed that p-niclosamide significantly inhibited the tumor burden of nude mice subcutaneously bearing T315I-BCR-ABL-expressing CML cells, and prolonged the survival of allografted leukemic mice harboring BaF3-T315I-BCR-ABL. We conclude that niclosamide is active against T315I-BCR-ABL-expressing cells, and may be a promising agent for CML patients regardless of T315I mutation status.
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104
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Liu C, Nie D, Li J, Du X, Lu Y, Li Y, Zhou J, Jin Y, Pan J. Antitumor Effects of Blocking Protein Neddylation in T315I-BCR-ABL Leukemia Cells and Leukemia Stem Cells. Cancer Res 2018; 78:1522-1536. [PMID: 29321163 DOI: 10.1158/0008-5472.can-17-1733] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 10/27/2017] [Accepted: 01/05/2018] [Indexed: 11/16/2022]
Abstract
Imatinib revolutionized the treatment of chronic myeloid leukemia (CML), but drug resistance and disease recurrence remain a challenge. In this study, we suggest a novel strategy based on blocking protein neddylation to address BCR-ABL point mutations and leukemia stem cells (LSC) that lie at the root of imatinib-resistant recurrences. On the basis of the finding that the NEDD8-activating enzyme subunit NAE1 is overexpressed in CML cells, we hypothesized that the function of certain neddylation-dependent protein substrates might be targeted to therapeutic ends in imatinib-resistant CML cells and LSCs. In support of this hypothesis, we demonstrated that the NAE1 inhibitor MLN4924 induced G2-M-phase arrest and apoptosis in bulk CML cells with wild-type p53, regardless of their T315I mutation status in BCR-ABL. Moreover, MLN4924 inhibited the survival and self-renewal of primary human CML CD34+ cells and LSCs in CML-bearing mice via accumulation of p27kip1 in the nucleus. Notably, p27kip1 silencing attenuated the suppressive effect of MLN4924 on the maintenance of LSCs in CML-bearing mice. Taken together, our findings offer a preclinical proof of concept for targeting protein neddylation as a novel therapeutic strategy to override mutational and LSC-derived imatinib resistance in CML.Significance: These findings highlight a mediator of protein neddylation, a type of protein turnover mechanism, as a viable therapeutic target against imatinib-resistant forms of chronic myelogenous leukemia. Cancer Res; 78(6); 1522-36. ©2018 AACR.
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Affiliation(s)
- Chang Liu
- Jinan University Institute of Tumor Pharmacology, College of Pharmacy, Jinan University; State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Danian Nie
- Department of Hematology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Juan Li
- Department of Hematology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Xin Du
- Department of Hematology, Guangdong General Hospital/Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Yuhong Lu
- Department of Hematology, The First Affiliated Hospital, Jinan University, Guangzhou, China
| | - Yangqiu Li
- Department of Hematology, The First Affiliated Hospital, Jinan University, Guangzhou, China
| | - Jingfeng Zhou
- Jinan University Institute of Tumor Pharmacology, College of Pharmacy, Jinan University; State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Yanli Jin
- Jinan University Institute of Tumor Pharmacology, College of Pharmacy, Jinan University; State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China.
| | - Jingxuan Pan
- Jinan University Institute of Tumor Pharmacology, College of Pharmacy, Jinan University; State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China.
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105
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Chiang K, Zielinska AE, Shaaban AM, Sanchez-Bailon MP, Jarrold J, Clarke TL, Zhang J, Francis A, Jones LJ, Smith S, Barbash O, Guccione E, Farnie G, Smalley MJ, Davies CC. PRMT5 Is a Critical Regulator of Breast Cancer Stem Cell Function via Histone Methylation and FOXP1 Expression. Cell Rep 2017; 21:3498-3513. [PMID: 29262329 PMCID: PMC5746596 DOI: 10.1016/j.celrep.2017.11.096] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 11/01/2017] [Accepted: 11/28/2017] [Indexed: 12/26/2022] Open
Abstract
Breast cancer progression, treatment resistance, and relapse are thought to originate from a small population of tumor cells, breast cancer stem cells (BCSCs). Identification of factors critical for BCSC function is therefore vital for the development of therapies. Here, we identify the arginine methyltransferase PRMT5 as a key in vitro and in vivo regulator of BCSC proliferation and self-renewal and establish FOXP1, a winged helix/forkhead transcription factor, as a critical effector of PRMT5-induced BCSC function. Mechanistically, PRMT5 recruitment to the FOXP1 promoter facilitates H3R2me2s, SET1 recruitment, H3K4me3, and gene expression. Our findings are clinically significant, as PRMT5 depletion within established tumor xenografts or treatment of patient-derived BCSCs with a pre-clinical PRMT5 inhibitor substantially reduces BCSC numbers. Together, our findings highlight the importance of PRMT5 in BCSC maintenance and suggest that small-molecule inhibitors of PRMT5 or downstream targets could be an effective strategy eliminating this cancer-causing population.
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Affiliation(s)
- Kelly Chiang
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Agnieszka E Zielinska
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Abeer M Shaaban
- Department of Cellular Pathology, Queen Elizabeth Hospital Birmingham, and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham B15 2GW, UK
| | - Maria Pilar Sanchez-Bailon
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - James Jarrold
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Thomas L Clarke
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Jingxian Zhang
- Institute of Molecular and Cell Biology (IMCB), A(∗)STAR (Agency for Science, Technology and Research), 61 Biopolis Drive, Proteos Building #3-06, 138673 Singapore, Singapore
| | - Adele Francis
- Department of Cellular Pathology, Queen Elizabeth Hospital Birmingham, and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham B15 2GW, UK
| | - Louise J Jones
- Centre for Tumour Biology, Barts Cancer Institute, A Cancer Research UK Centre of Excellence, Queen Mary University of London, John Vane Science Centre, London EC1M 6BQ, UK
| | - Sally Smith
- Centre for Tumour Biology, Barts Cancer Institute, A Cancer Research UK Centre of Excellence, Queen Mary University of London, John Vane Science Centre, London EC1M 6BQ, UK
| | - Olena Barbash
- Cancer Epigenetics DPU, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Ernesto Guccione
- Institute of Molecular and Cell Biology (IMCB), A(∗)STAR (Agency for Science, Technology and Research), 61 Biopolis Drive, Proteos Building #3-06, 138673 Singapore, Singapore; Department of Oncological Sciences and Pharmacological Sciences, Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Gillian Farnie
- Structural Genomics Consortium, Botnar Research Centre, NDORMS, University of Oxford, Oxford OX3 7LD, UK
| | - Matthew J Smalley
- European Cancer Stem Cell Research Institute, Cardiff School of Biosciences, Cardiff University, Cardiff CF24 4HQ, UK
| | - Clare C Davies
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK.
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106
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Jin Y, Zhang P, Wang Y, Jin B, Zhou J, Zhang J, Pan J. Neddylation Blockade Diminishes Hepatic Metastasis by Dampening Cancer Stem-Like Cells and Angiogenesis in Uveal Melanoma. Clin Cancer Res 2017; 24:3741-3754. [PMID: 29233905 DOI: 10.1158/1078-0432.ccr-17-1703] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 09/03/2017] [Accepted: 12/05/2017] [Indexed: 11/16/2022]
Abstract
Purpose: Liver metastasis is the major and direct cause of death in patients with uveal melanoma (UM). There is no effective therapy for patients with metastatic UM. Improved treatments of hepatic metastatic patients with UM were urgently needed. Inspired by readily detectable key components in the neddylation pathway in UM cells, we aimed at exploring whether neddylation pathway was a therapeutic target for liver metastatic UM.Experimental Design: Expression of key proteins in the neddylation pathway in UM was detected by Western blotting, real-time quantitative RT-PCR (qRT-PCR), and immunohistochemical staining. Cellular proliferation, apoptosis, cell cycle, migration, and cancer stem-like cells (CSCs) properties were examined upon treatment with MLN4924, a potent and selective NAE inhibitor. Antitumor activity and frequency of CSCs were determined by using a NOD-SCID mouse xenograft model. Liver metastasis was evaluated by use of a NOD-scid-IL2Rg-/- mouse model.Results: NAE1 expression was readily detectable in UM. Inhibition of the neddylation pathway by MLN4924 repressed the CSCs properties in UM (capacities of tumorsphere formation and serially replating, aldehyde dehydrogenase-positive cells, and frequency of CSC) through Slug protein degradation. MLN4924 treatment disturbed the paracrine secretion of NF-κB-mediated VEGF-C and its dependent angiogenesis. The inhibitory effect of neddylation blockade on proliferation, which was confirmed by xenografted UM tumor in NOD-SCID mice, was involved in activation of ATM-Chk1-Cdc25C DNA damage response, and G2-M phase arrest. Neddylation inhibition profoundly inhibited hepatic metastasis in UM.Conclusions: Our studies validate the neddylation pathway as a promising therapeutic target for the treatment of patients with hepatic metastasis of UM. Clin Cancer Res; 24(15); 3741-54. ©2017 AACRSee related commentary by Yang et al., p. 3477.
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Affiliation(s)
- Yanli Jin
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Ping Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Yun Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Bei Jin
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Jingfeng Zhou
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Jing Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Jingxuan Pan
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China.
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107
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Bhatia R. Novel approaches to therapy in CML. HEMATOLOGY. AMERICAN SOCIETY OF HEMATOLOGY. EDUCATION PROGRAM 2017; 2017:115-120. [PMID: 29222245 PMCID: PMC6142563 DOI: 10.1182/asheducation-2017.1.115] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Treatment with tyrosine kinase inhibitors (TKIs) results in remission and prolongation of survival in most chronic myeloid leukemia (CML) patients but fails to eliminate the leukemia stem cells (LSCs) responsible for disease development and propagation. This accounts for the clinical observation that TKI discontinuation leads to rapid leukemia relapse. Most patients require continued treatment to prevent relapse, with associated risk of relapse, toxicity, teratogenic effects, financial burden, and noncompliance. Understanding LSC resistance to TKI and development of strategies to increase the proportion of CML patients achieving treatment-free remissions is a critical area of investigation in CML. In addition, LSCs are the source of TKI resistance, relapse, or disease progression, which is another major area of need in CML treatment. It is now understood that BCR-ABL kinase-independent mechanisms are responsible for retention of LSC subpopulations. It is likely that both cell-intrinsic and microenvironmental mechanisms contribute to LSC maintenance. Here, we review the current understanding of mechanisms underlying persistence of CML LSCs during TKI treatment, recently described approaches to target these cells and emerging clinical trials, and the challenges impeding more rapid progress in achieving cures for a greater number of CML patients.
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MESH Headings
- Drug Resistance, Neoplasm/drug effects
- Fusion Proteins, bcr-abl/antagonists & inhibitors
- Fusion Proteins, bcr-abl/metabolism
- Humans
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/enzymology
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Protein Kinase Inhibitors/adverse effects
- Protein Kinase Inhibitors/therapeutic use
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Affiliation(s)
- Ravi Bhatia
- Division of Hematology/Oncology, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL
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108
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Wang Z, Kong J, Wu Y, Zhang J, Wang T, Li N, Fan J, Wang H, Zhang J, Ling R. PRMT5 determines the sensitivity to chemotherapeutics by governing stemness in breast cancer. Breast Cancer Res Treat 2017; 168:531-542. [DOI: 10.1007/s10549-017-4597-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 11/22/2017] [Indexed: 01/07/2023]
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109
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Zhou J, Nie D, Li J, Du X, Lu Y, Li Y, Liu C, Dai W, Wang Y, Jin Y, Pan J. PTEN Is Fundamental for Elimination of Leukemia Stem Cells Mediated by GSK126 Targeting EZH2 in Chronic Myelogenous Leukemia. Clin Cancer Res 2017; 24:145-157. [PMID: 29070525 DOI: 10.1158/1078-0432.ccr-17-1533] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 09/21/2017] [Accepted: 10/18/2017] [Indexed: 11/16/2022]
Abstract
Purpose: Leukemia stem cells (LSCs) are an important source of tyrosine kinase inhibitor resistance and disease relapse in patients with chronic myelogenous leukemia (CML). Targeting LSCs may be an attractive strategy to override this thorny problem. Given that EZH2 was overexpressed in primary CML CD34+ cells, our purpose in this study was to evaluate the effects of targeting EZH2 on CML LSCs and clarify its underlying mechanism.Experimental Design: Human primary CML CD34+ cells and retrovirally BCR-ABL-driven CML mouse models were employed to evaluate the effects of suppression of EZH2 by GSK126- or EZH2-specific shRNA in vitro and in vivo Recruitment of EZH2 and H3K27me3 on the promoter of tumor-suppressor gene PTEN in CML cells was measured by chromatin immunoprecipitation assay.Results: Our results showed that pharmacologic inhibition of EZH2 by GSK126 not only elicited apoptosis and restricted cell growth in CML bulk leukemia cells, but also decreased LSCs in CML CD34+ cells while sparing those from normal bone marrow CD34+ cells. Suppression of EZH2 by GSK126 or specific shRNA prolonged survival of CML mice and reduced the number of LSCs in mice. EZH2 knockdown resulted in elevation of PTEN and led to impaired recruitment of EZH2 and H3K27me3 on the promoter of PTEN gene. The effect of EZH2 knockdown in the CML mice was at least partially reversed by PTEN knockdown.Conclusions: These findings improve the understanding of the epigenetic regulation of stemness in CML LSCs and warrant clinical trial of GSK126 in refractory patients with CML. Clin Cancer Res; 24(1); 145-57. ©2017 AACR.
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Affiliation(s)
- Jingfeng Zhou
- Jinan University Institute of Tumor Pharmacology, College of Pharmacy, Jinan University, Guangzhou, China
| | - Danian Nie
- Department of Hematology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Juan Li
- Department of Hematology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Xin Du
- Department of Hematology, Guangdong General Hospital/Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Yuhong Lu
- Department of Hematology, The First Affiliated Hospital, Jinan University, Guangzhou, China
| | - Yangqiu Li
- Department of Hematology, The First Affiliated Hospital, Jinan University, Guangzhou, China
| | - Chang Liu
- Jinan University Institute of Tumor Pharmacology, College of Pharmacy, Jinan University, Guangzhou, China
| | - Wei Dai
- Jinan University Institute of Tumor Pharmacology, College of Pharmacy, Jinan University, Guangzhou, China
| | - Yun Wang
- Jinan University Institute of Tumor Pharmacology, College of Pharmacy, Jinan University, Guangzhou, China
| | - Yanli Jin
- Jinan University Institute of Tumor Pharmacology, College of Pharmacy, Jinan University, Guangzhou, China.
| | - Jingxuan Pan
- Jinan University Institute of Tumor Pharmacology, College of Pharmacy, Jinan University, Guangzhou, China. .,State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
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110
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The PAF complex regulation of Prmt5 facilitates the progression and maintenance of MLL fusion leukemia. Oncogene 2017; 37:450-460. [PMID: 28945229 PMCID: PMC5785415 DOI: 10.1038/onc.2017.337] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 07/20/2017] [Accepted: 07/31/2017] [Indexed: 02/06/2023]
Abstract
Acute myeloid leukemia (AML) is a disease associated with epigenetic dysregulation. 11q23 translocations involving the H3K4 methyltransferase MLL1 (KMT2A) generate oncogenic fusion proteins with deregulated transcriptional potential. The Polymerase Associated Factor complex (PAFc) is an epigenetic co-activator complex that makes direct contact with MLL fusion proteins and is involved in AML, however its functions are not well understood. Here, we explored the transcriptional targets regulated by the PAFc that facilitate leukemia by performing RNA-sequencing after conditional loss of the PAFc subunit Cdc73. We found Cdc73 promotes expression of an early hematopoietic progenitor gene program that prevents differentiation. Among the target genes, we confirmed the protein arginine methyltransferase Prmt5 is a direct target that is positively regulated by a transcriptional unit that includes the PAFc, MLL1, HOXA9 and STAT5 in leukemic cells. We observed reduced PRMT5-mediated H4R3me2s following excision of Cdc73 placing this histone modification downstream of the PAFc and revealing a novel mechanism between the PAFc and Prmt5. Knock down or pharmacologic inhibition of Prmt5 causes a G1 arrest and reduced proliferation resulting in extended leukemic disease latency in vivo. Overall, we demonstrate the PAFc regulates Prmt5 to facilitate leukemic progression and is a potential therapeutic target for AMLs.
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111
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Shen N, Jiang L, Li Q, Cui J, Zhou S, Cheng F, Zhong Z, Meng L, You Y, Zhu X, Zou P. The epigenetic effect of microRNA in BCR-ABL1-positive microvesicles during the transformation of normal hematopoietic transplants. Oncol Rep 2017; 38:3278-3284. [DOI: 10.3892/or.2017.5966] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 08/16/2017] [Indexed: 11/06/2022] Open
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112
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113
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Koschmieder S, Vetrie D. Epigenetic dysregulation in chronic myeloid leukaemia: A myriad of mechanisms and therapeutic options. Semin Cancer Biol 2017; 51:180-197. [PMID: 28778403 DOI: 10.1016/j.semcancer.2017.07.006] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 07/13/2017] [Accepted: 07/28/2017] [Indexed: 01/08/2023]
Abstract
The onset of global epigenetic changes in chromatin that drive tumor proliferation and heterogeneity is a hallmark of many forms of cancer. Identifying the epigenetic mechanisms that govern these changes and developing therapeutic approaches to modulate them, is a well-established avenue pursued in translational cancer medicine. Chronic myeloid leukemia (CML) arises clonally when a hematopoietic stem cell (HSC) acquires the capacity to produce the constitutively active tyrosine kinase BCR-ABL1 fusion protein which drives tumor development. Treatment with tyrosine kinase inhibitors (TKI) that target BCR-ABL1 has been transformative in CML management but it does not lead to cure in the vast majority of patients. Thus novel therapeutic approaches are required and these must target changes to biological pathways that are aberrant in CML - including those that occur when epigenetic mechanisms are altered. These changes may be due to alterations in DNA or histones, their biochemical modifications and requisite 'writer' proteins, or to dysregulation of various types of non-coding RNAs that collectively function as modulators of transcriptional control and DNA integrity. Here, we review the evidence for subverted epigenetic mechanisms in CML and how these impact on a diverse set of biological pathways, on disease progression, prognosis and drug resistance. We will also discuss recent progress towards developing epigenetic therapies that show promise to improve CML patient care and may lead to improved cure rates.
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Affiliation(s)
- Steffen Koschmieder
- Department of Hematology, Oncology, Hemostaseology, and Stem Cell Transplantation, Faculty of Medicine, RWTH Aachen University, Aachen, Germany.
| | - David Vetrie
- Epigenetics Unit, Wolfson Wohl Cancer Research Centre, Institute of Cancer Sciences, University of Glasgow, Glasgow, United Kingdom.
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114
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In vitro and in vivo anti-uveal melanoma activity of JSL-1, a novel HDAC inhibitor. Cancer Lett 2017; 400:47-60. [DOI: 10.1016/j.canlet.2017.04.028] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 04/08/2017] [Accepted: 04/14/2017] [Indexed: 12/27/2022]
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115
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Zhang B, Zhang J, Pan J. Pristimerin effectively inhibits the malignant phenotypes of uveal melanoma cells by targeting NF‑κB pathway. Int J Oncol 2017; 51:887-898. [PMID: 28766683 DOI: 10.3892/ijo.2017.4079] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Accepted: 07/13/2017] [Indexed: 11/05/2022] Open
Abstract
Uveal melanoma (UM) is a highly aggressive intraocular malignancy that lacks any effective targeted-therapy. Neither survival nor prognosis has been improved for the past decades in patients with metastatic UM. NF‑κB pathway is reported to be abnormally activated in UM. However, the role of NF‑κB pathway as a potential therapeutical target in UM remains unclear. Here, the effect of pristimerin, a potent inhibitor of NF‑κB pathway, on UM cells in terms of growth, apoptosis, motility, invasion and cancer stem-like cells (CSCs) was evaluated in vitro. We showed that pristimerin suppressed tumor necrosis factor α (TNFα)-induced IκBα phosphorylation, translocation of p65, and expression of NF‑κB-dependent genes. Moreover, pristimerin decreased cell viability and clonogenic ability of UM cells. A synergistic effect was observed in the treatment of pristimerin combined with vinblastine, a frontline therapeutic agent, in UM. Pristimerin led to a significant increase in the Annexin V+ cell population as measured by flow cytometry. We also observed that pristimerin impaired the abilities of migration and invasion in UM cells. Furthermore, pristimerin eliminated the ALDH+ cells and weakened serial re-plating ability of melanosphere. Collectively, pristimerin shows remarkable anticancer activities in UM cells through inactivating NF‑κB pathway, revealing that pristimerin may be a promising therapeutic agent in UM.
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Affiliation(s)
- Biao Zhang
- Institute of Tumor Pharmacology, College of Pharmacy, Jinan University, Guangzhou, Guangdong 510060, P.R. China
| | - Jing Zhang
- Institute of Tumor Pharmacology, College of Pharmacy, Jinan University, Guangzhou, Guangdong 510060, P.R. China
| | - Jingxuan Pan
- Institute of Tumor Pharmacology, College of Pharmacy, Jinan University, Guangzhou, Guangdong 510060, P.R. China
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116
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Genetic deletion or small-molecule inhibition of the arginine methyltransferase PRMT5 exhibit anti-tumoral activity in mouse models of MLL-rearranged AML. Leukemia 2017; 32:499-509. [PMID: 28663579 DOI: 10.1038/leu.2017.206] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 05/31/2017] [Accepted: 06/21/2017] [Indexed: 12/13/2022]
Abstract
The hematological malignancies classified as mixed lineage leukemias (MLL) harbor fusions of the MLL1 gene to partners that are members of transcriptional elongation complexes. MLL-rearranged leukemias are associated with extremely poor prognosis, and response to conventional therapies and efforts to identify molecular targets are urgently needed. Using mouse models of MLL-rearranged acute myeloid leukemia, here we show that genetic inactivation or small-molecule inhibition of the protein arginine methyltransferase PRMT5 exhibit anti-tumoral activity in MLL-fusion protein-driven transformation. Genome-wide transcriptional analysis revealed that inhibition of PRMT5 methyltransferase activity overrides the differentiation block in leukemia cells without affecting the expression of MLL-fusion direct oncogenic targets. Furthermore, we find that this differentiation block is mediated by transcriptional silencing of the cyclin-dependent kinase inhibitor p21 (CDKN1a) gene in leukemia cells. Our study provides pre-clinical rationale for targeting PRMT5 using small-molecule inhibitors in the treatment of leukemias harboring MLL rearrangements.
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117
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Chen L, Pan J. Dual cyclin-dependent kinase 4/6 inhibition by PD-0332991 induces apoptosis and senescence in oesophageal squamous cell carcinoma cells. Br J Pharmacol 2017; 174:2427-2443. [PMID: 28444744 DOI: 10.1111/bph.13836] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2016] [Revised: 03/22/2017] [Accepted: 04/17/2017] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND AND PURPOSE Aberrant activation of the cyclin D1-cyclin-dependent kinase 4/6 (CDK4/6)-Rb signalling pathway is common in oesophageal squamous cell carcinoma (ESCC). PD-0332991, a highly specific inhibitor of CDK4/6, has potent antitumour activity against many types of cancer. The purpose of this study was to examine the in vitro and in vivo antineoplastic effect of PD-0332991 against the growth and metastasis of ESCC cells. EXPERIMENTAL APPROACH Cell viability and any synergy between PD-0332991 and 5-fluorouracil or cisplatin were measured by MTS assay and CalcuSyn software respectively. Cell migration and invasion were detected by wound healing and transwell assays. Apoptosis was evaluated by flow cytometry after staining annexin V-FITC/PI. Cellular senescence was assessed by measuring SA-β-gal activity. Nude mouse xenograft models of ESCC were employed to determine the in vivo activity of PD-0332991 against tumour growth and lung metastasis. KEY RESULTS PD-0332991 inhibited cellular growth and induced mitochondrial-dependent apoptosis in ESCC cells. PD-0332991 also suppressed migration, invasion and the expression of MMP-2 in ESCC cells. Furthermore, PD-0332991 treatment caused cell senescence in a FOXM1-dependent manner. In addition, there was synergy between PD-0332991 and cisplatin or 5-fluorouracil. Importantly, the xenografted tumour experiments demonstrated that PD-0332991 potently inhibits ESCC cell growth and lung metastasis. CONCLUSIONS AND IMPLICATIONS PD-0332991 can elicit a strong antitumour activity against ESCC growth and metastasis and may be a promising candidate drug for the treatment of patients with ESCC. Our results warrant a clinical trial to further evaluate the efficacy of PD-0332991 in ESCC patients, even those with metastasis.
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Affiliation(s)
- Liang Chen
- Jinan University Institute of Tumor Pharmacology, College of Pharmacy, Jinan University, Guangzhou, China
| | - Jingxuan Pan
- Jinan University Institute of Tumor Pharmacology, College of Pharmacy, Jinan University, Guangzhou, China
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118
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Gao D, Herman JG, Cui H, Jen J, Fuks F, Brock MV, Ushijima T, Croce C, Akiyama Y, Guo M. Meeting Report of the Fifth International Cancer Epigenetics Conference in Beijing, China, October 2016. Epigenomics 2017; 9:937-941. [PMID: 28530839 DOI: 10.2217/epi-2017-0030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Fifth International Cancer Epigenetics Conference, Beijing, China, 21-23 October 2016 This meeting reported many new findings in the field of cancer epigenetics, including basic science, translational and clinical studies. In this report, we summarize some of the main advancements and prospects in cancer epigenetics presented at this meeting.
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Affiliation(s)
- Dan Gao
- Department of Gastroenterology & Hepatology, Chinese PLA General Hospital, Beijing 100853, China.,School of Medicine, Nankai University, Tianjin 300071, China
| | - James G Herman
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburg, PA 15232, USA
| | - Hengmi Cui
- Institute of Epigenetics & Epigenomics, Yangzhou University, Yangzhou 225000, China
| | - Jin Jen
- Department of Laboratory of Medicine & Pathology, Mayo Clinic, Rochester, MN 55905, USA
| | - Francois Fuks
- Laboratory of Cancer Epigenetics, Faculty of Medicine, ULB Cancer Research Center (U-CRC), Université Libre de Bruxelles (ULB), Brussels 1070, Belgium
| | - Malcolm V Brock
- Oncology Center, Johns Hopkins University, Baltimore, MD 21231, USA
| | - Toshikazu Ushijima
- Division of Epigenomics, National Cancer Center Research Institute, Tokyo 104-0045, Japan
| | - Carlo Croce
- Department of Cancer Biology & Genetics, College of Medicine, The Ohio State University Comprehensive Cancer Center, Columbus, OH 43210, USA
| | - Yoshimitsu Akiyama
- Department of Molecular Oncology, Graduate School of Medical & Dental Sciences, Tokyo Medical & Dental University, Tokyo 113-8519, Japan
| | - Mingzhou Guo
- Department of Gastroenterology & Hepatology, Chinese PLA General Hospital, Beijing 100853, China
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119
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Wainwright EN, Scaffidi P. Epigenetics and Cancer Stem Cells: Unleashing, Hijacking, and Restricting Cellular Plasticity. Trends Cancer 2017; 3:372-386. [PMID: 28718414 PMCID: PMC5506260 DOI: 10.1016/j.trecan.2017.04.004] [Citation(s) in RCA: 221] [Impact Index Per Article: 31.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Revised: 03/30/2017] [Accepted: 04/10/2017] [Indexed: 02/07/2023]
Abstract
Epigenetic mechanisms have emerged as key players in cancer development which affect cellular states at multiple stages of the disease. During carcinogenesis, alterations in chromatin and DNA methylation resulting from genetic lesions unleash cellular plasticity and favor oncogenic cellular reprogramming. At later stages, during cancer growth and progression, additional epigenetic changes triggered by interaction with the microenvironment modulate cancer cell phenotypes and properties, and shape tumor architecture. We review here recent advances highlighting the interplay between epigenetics, genetics, and cell-to-cell signaling in cancer, with particular emphasis on mechanisms relevant for cancer stem cell formation (CSC) and function. Epigenetic regulators are one of the most commonly mutated classes of genes in cancer. During cancer initiation, mutated epigenetic regulators lead to oncogenic cellular reprogramming and promote the acquisition of uncontrolled self-renewal. The emergence of CSCs requires elaborate reorganization of the epigenome. During cancer growth, epigenetic mechanisms integrate the effect of cell-intrinsic (i.e., subclonal mutations) and cell-extrinsic (i.e., signaling from the microenvironment) changes and establish intratumoral heterogeneity, either promoting or inhibiting the CSC state. ‘Loose’ epigenetic constraints in cancer cells enhance cellular plasticity and allow reversible transitions between different phenotypic states. Enhanced cellular plasticity favors cancer cell adaptability and resistance to therapy. Modulation of epigenetic processes allows targeting of the most downstream determinants of the CSC state.
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Affiliation(s)
- Elanor N Wainwright
- Cancer Epigenetics Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Paola Scaffidi
- Cancer Epigenetics Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK; UCL Cancer Institute, University College London, London WC1E 6DD, UK.
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Abstract
In the past few years, it has become clear that mutations in epigenetic regulatory genes are common in human cancers. Therapeutic strategies are now being developed to target cancers with mutations in these genes using specific chemical inhibitors. In addition, a complementary approach based on the concept of synthetic lethality, which allows exploitation of loss-of-function mutations in cancers that are not targetable by conventional methods, has gained traction. Both of these approaches are now being tested in several clinical trials. In this Review, we present recent advances in epigenetic drug discovery and development, and suggest possible future avenues of investigation to drive progress in this area.
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121
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Clarke CJ, Holyoake TL. Preclinical approaches in chronic myeloid leukemia: from cells to systems. Exp Hematol 2017; 47:13-23. [PMID: 28017647 PMCID: PMC5333535 DOI: 10.1016/j.exphem.2016.11.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 11/19/2016] [Indexed: 12/22/2022]
Abstract
Advances in the design of targeted therapies for the treatment of chronic myeloid leukemia (CML) have transformed the prognosis for patients diagnosed with this disease. However, leukemic stem cell persistence, drug intolerance, drug resistance, and advanced-phase disease represent unmet clinical needs demanding the attention of CML investigators worldwide. The availability of appropriate preclinical models is essential to efficiently translate findings from the bench to the clinic. Here we review the current approaches taken to preclinical work in the CML field, including examples of commonly used in vivo models and recent successes from systems biology-based methodologies.
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MESH Headings
- Animals
- Animals, Genetically Modified
- Cell Line, Transformed
- Cell Transplantation
- Disease Models, Animal
- Drug Evaluation, Preclinical
- Humans
- In Vitro Techniques
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/etiology
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/therapy
- Transduction, Genetic
- Transgenes
- Tumor Cells, Cultured
- Xenograft Model Antitumor Assays
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Affiliation(s)
- Cassie J Clarke
- Paul O'Gorman Leukaemia Research Centre, Institute of Cancer Sciences, University of Glasgow, Gartnavel General Hospital, Glasgow, UK
| | - Tessa L Holyoake
- Paul O'Gorman Leukaemia Research Centre, Institute of Cancer Sciences, University of Glasgow, Gartnavel General Hospital, Glasgow, UK.
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122
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Ma YW, Liu YZ, Pan JX. Verteporfin induces apoptosis and eliminates cancer stem-like cells in uveal melanoma in the absence of light activation. Am J Cancer Res 2016; 6:2816-2830. [PMID: 28042502 PMCID: PMC5199756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 10/24/2016] [Indexed: 06/06/2023] Open
Abstract
Uveal melanoma (UM) is the most common primary ocular malignancy in adults. Currently, no beneficial systemic therapy is available; therefore, there is an urgent need for effective targeted therapeutic drugs. As verteporfin has shown anti-neoplastic activity in several types of cancers, here we hypothesized and investigated the efficacy of verteporfin against UM cells without light activation. MTS assay, flow cytometry analysis of apoptosis, Western blotting of relevant proteins, transwell migration and invasion assay, melanosphere culture, and measurement of ALDH+ populations, were used to evaluate the effects of verteporfin on UM cells. We found that verteporfin disrupted the interaction between YAP and TEAD4 in UM cells and decreased the expression of YAP targeted downstream genes. Verteporfin treatment decreased the cytoplasmic and nuclear levels of YAP and induced lysosome-dependent degradation of YAP protein. Verteporfin exhibited distinct inhibitory effect on the proliferation of four lines of UM cells (e.g., 92.1, Mel 270, Omm 1 and Omm 2.3), and induced apoptosis through the intrinsic pathway. Additionally, verteporfin suppressed migration and invasion of UM cells, impaired the traits of cancer stem-like cells (e.g., melanosphere formation capacity, and ALDH+ cell population). This study demonstrated the anti-neoplastic activity of verteporfin against UM cells in vitro, providing a rationale for evaluating this agent in clinical investigation.
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Affiliation(s)
- Ya-Wen Ma
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University Guangzhou, People's Republic of China
| | - Yi-Zhi Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University Guangzhou, People's Republic of China
| | - Jing-Xuan Pan
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University Guangzhou, People's Republic of China
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123
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Jin Y, Nie D, Li J, Du X, Lu Y, Li Y, Liu C, Zhou J, Pan J. Gas6/AXL Signaling Regulates Self-Renewal of Chronic Myelogenous Leukemia Stem Cells by Stabilizing β-Catenin. Clin Cancer Res 2016; 23:2842-2855. [PMID: 27852702 DOI: 10.1158/1078-0432.ccr-16-1298] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2016] [Revised: 10/14/2016] [Accepted: 11/07/2016] [Indexed: 11/16/2022]
Abstract
Purpose: Quiescent leukemia stem cells (LSC) are important resources of resistance and relapse in chronic myelogenous leukemia (CML). Thus, strategies eradicating CML LSCs are required for cure. In this study, we discovered that AXL tyrosine kinase was selectively overexpressed in primary CML CD34+ cells. However, the role of AXL and its ligand Gas6 secreted by stromal cells in the regulation of self-renewal capacity of LSCs has not been well investigated.Experimental Design: The function of CML CD34+ cells was evaluated by flow cytometer, CFC/replating, long-term culture-initiating cells (LTC-IC), CML mouse model driven by human BCR-ABL gene and NOD-scid-IL2Rg-/- (NSI) mice.Results: AXL was selectively overexpressed in primary CML CD34+ cells. AXL knockdown reduced the survival and self-renewal capacity of human CML CD34+ cells. Pharmacologic inhibition of AXL reduced the survival and self-renewal capacity of human CML LSCs in vitro and in long-term grafts in NSI mice. Human CML CD34+ cells conscripted bone marrow-derived stromal cells (BMDSC) and primary mesenchymal stem cells (MSC) to secrete Gas6 to form a paracrine loop that promoted self-renewal of LSCs. Suppression of AXL by shRNA and inhibitor prolonged survival of CML mice and reduced the growth of LSCs in mice. Gas6/AXL ligation stabilizes β-catenin in an AKT-dependent fashion in human CML CD34+ cells.Conclusions: Our findings improve the understanding of LSC regulation and validate Gas6/AXL as a pair of therapeutic targets to eliminate CML LSCs. Clin Cancer Res; 23(11); 2842-55. ©2016 AACR.
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Affiliation(s)
- Yanli Jin
- Jinan University Institute of Tumor Pharmacology; State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Danian Nie
- Department of Hematology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Juan Li
- Department of Hematology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Xin Du
- Department of Hematology, Guangdong General Hospital/Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Yuhong Lu
- Department of Hematology, The First Affiliated Hospital, Jinan University, Guangzhou, China
| | - Yangqiu Li
- Department of Hematology, The First Affiliated Hospital, Jinan University, Guangzhou, China
| | - Chang Liu
- Jinan University Institute of Tumor Pharmacology; State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Jingfeng Zhou
- Jinan University Institute of Tumor Pharmacology; State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Jingxuan Pan
- Jinan University Institute of Tumor Pharmacology; State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China. .,Collaborative Innovation Center for Cancer Medicine, State Key Laboratory of Oncology in South China, Sun Yat-Sen University Cancer Center, Guangzhou, China
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