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Bingul M, Arndt GM, Marshall GM, Black DS, Cheung BB, Kumar N. Synthesis and Characterisation of Novel Tricyclic and Tetracyclic Furoindoles: Biological Evaluation as SAHA Enhancer against Neuroblastoma and Breast Cancer Cells. Molecules 2021; 26:molecules26195745. [PMID: 34641289 PMCID: PMC8510456 DOI: 10.3390/molecules26195745] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 09/08/2021] [Accepted: 09/14/2021] [Indexed: 11/16/2022] Open
Abstract
The dihydropyranoindole structures were previously identified as promising scaffolds for improving the anti-cancer activity of histone deacetylase inhibitors. This work describes the synthesis of related furoindoles and their ability to synergize with suberoylanilide hydroxamic acid (SAHA) against neuroblastoma and breast cancer cells. The nucleophilic substitution of hydroxyindole methyl esters with α-haloketones yielded the corresponding arylether ketones, which were subsequently cyclized to tricyclic and tetracyclic furoindoles. The furoindoles showed promising individual cytotoxic efficiency against breast cancer cells, as well as decent SAHA enhancement against cancer cells in select cases. Interestingly, the best IC50 value was obtained with the non-cyclized intermediate.
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Affiliation(s)
- Murat Bingul
- School of Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia;
- Lowy Cancer Research Centre, Children’s Cancer Institute, UNSW Sydney, Sydney, NSW 2031, Australia; (G.M.A.); (G.M.M.)
- School of Pharmacy, Dicle University, Diyarbakır 21280, Turkey
| | - Greg M. Arndt
- Lowy Cancer Research Centre, Children’s Cancer Institute, UNSW Sydney, Sydney, NSW 2031, Australia; (G.M.A.); (G.M.M.)
- ACRF Drug Discovery Centre for Childhood Cancer, Children’s Cancer Institute Australia for Medical Research, Lowy Cancer Research Centre, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Glenn M. Marshall
- Lowy Cancer Research Centre, Children’s Cancer Institute, UNSW Sydney, Sydney, NSW 2031, Australia; (G.M.A.); (G.M.M.)
- Kids Cancer Centre, Sydney Children’s Hospital, Randwick, NSW 2031, Australia
| | - David StC. Black
- School of Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia;
- Correspondence: (D.S.B.); (B.B.C.); (N.K.); Tel.: +61-2-9385-4657 (D.S.B.); +61-2-9385-2450 (B.B.C.); +61-2-9385-4698 (N.K.)
| | - Belamy B. Cheung
- Lowy Cancer Research Centre, Children’s Cancer Institute, UNSW Sydney, Sydney, NSW 2031, Australia; (G.M.A.); (G.M.M.)
- School of Women’s and Children’s Health, UNSW Sydney, Sydney, NSW 2052, Australia
- Correspondence: (D.S.B.); (B.B.C.); (N.K.); Tel.: +61-2-9385-4657 (D.S.B.); +61-2-9385-2450 (B.B.C.); +61-2-9385-4698 (N.K.)
| | - Naresh Kumar
- School of Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia;
- Correspondence: (D.S.B.); (B.B.C.); (N.K.); Tel.: +61-2-9385-4657 (D.S.B.); +61-2-9385-2450 (B.B.C.); +61-2-9385-4698 (N.K.)
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Bingul M, Arndt GM, Marshall GM, Cheung BB, Kumar N, Black DS. Synthesis, Characterization and Biological Evaluation of Novel Dihydropyranoindoles Improving the Anticancer Effects of HDAC Inhibitors. Molecules 2020; 25:molecules25061377. [PMID: 32197360 PMCID: PMC7144403 DOI: 10.3390/molecules25061377] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 03/16/2020] [Accepted: 03/16/2020] [Indexed: 12/03/2022] Open
Abstract
The dihydropyranoindole scaffold was identified as a promising target for improving the anti-cancer activity of HDAC inhibitors from the preliminary screening of a library of compounds. A suitable methodology has been developed for the preparation of novel dihydropyranoindoles via the Hemetsberger indole synthesis using azido-phenylacrylates, derived from the reaction of corresponding alkynyl-benzaldehydes with methyl azidoacetate, followed by thermal cyclization in high boiling solvents. Anti-cancer activity of all the newly synthesized compounds was evaluated against the SH-SY5Y and Kelly neuroblastoma cells as well as the MDA-MB-231 and MCF-7 breast adenocarcinoma cell lines. Biological studies showed that the tetracyclic systems had significant cytotoxic activity at higher concentration against the neuroblastoma cancer cells. More importantly, these systems, at the lower concentration, considerably enhanced the SAHA toxicity. In addition to that, the toxicity of designated systems on the healthy human cells was found to be significantly less than the cancer cells.
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Affiliation(s)
- Murat Bingul
- School of Chemistry, UNSW Sydney, Sydney, NSW 2052, Australia;
- Children’s Cancer Institute, Lowy Cancer Research Centre, UNSW Sydney, Sydney, NSW 2052, Australia; (G.M.A.); (G.M.M.)
- School of Pharmacy, Dicle University, 21280 Diyarbakır, Turkey
| | - Greg M. Arndt
- Children’s Cancer Institute, Lowy Cancer Research Centre, UNSW Sydney, Sydney, NSW 2052, Australia; (G.M.A.); (G.M.M.)
- ACRF Drug Discovery Centre for Childhood Cancer, Children’s Cancer Institute, Lowy Cancer Research Centre, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Glenn M. Marshall
- Children’s Cancer Institute, Lowy Cancer Research Centre, UNSW Sydney, Sydney, NSW 2052, Australia; (G.M.A.); (G.M.M.)
- Kids Cancer Centre, Sydney Children’s Hospital, Randwick, NSW 2031, Australia
| | - Belamy B. Cheung
- Children’s Cancer Institute, Lowy Cancer Research Centre, UNSW Sydney, Sydney, NSW 2052, Australia; (G.M.A.); (G.M.M.)
- School of Women’s and Children’s Health, UNSW Sydney, Sydney, NSW 2052, Australia
- Correspondence: (B.B.C.); (N.K.); (D.S.B.); Tel.: +61-2-9385-2450 (B.B.C.); +61-2-9385-4698 (N.K.); +61-2-9385-4657 (D.S.B.)
| | - Naresh Kumar
- School of Chemistry, UNSW Sydney, Sydney, NSW 2052, Australia;
- Correspondence: (B.B.C.); (N.K.); (D.S.B.); Tel.: +61-2-9385-2450 (B.B.C.); +61-2-9385-4698 (N.K.); +61-2-9385-4657 (D.S.B.)
| | - David StC. Black
- School of Chemistry, UNSW Sydney, Sydney, NSW 2052, Australia;
- Correspondence: (B.B.C.); (N.K.); (D.S.B.); Tel.: +61-2-9385-2450 (B.B.C.); +61-2-9385-4698 (N.K.); +61-2-9385-4657 (D.S.B.)
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Bingul M, Tan O, Gardner CR, Sutton SK, Arndt GM, Marshall GM, Cheung BB, Kumar N, Black DS. Synthesis, Characterization and Anti-Cancer Activity of Hydrazide Derivatives Incorporating a Quinoline Moiety. Molecules 2016; 21:molecules21070916. [PMID: 27428941 PMCID: PMC6273134 DOI: 10.3390/molecules21070916] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 07/05/2016] [Accepted: 07/08/2016] [Indexed: 11/16/2022] Open
Abstract
Identification of the novel (E)-N′-((2-chloro-7-methoxyquinolin-3-yl)methylene)-3-(phenylthio)propanehydrazide scaffold 18 has led to the development of a new series of biologically active hydrazide compounds. The parent compound 18 and new quinoline derivatives 19–26 were prepared from the corresponding quinoline hydrazones and substituted carboxylic acids using EDC-mediated peptide coupling reactions. Further modification of the parent compound 18 was achieved by replacement of the quinoline moiety with other aromatic systems. All the newly synthesized compounds were evaluated for their anti-cancer activity against the SH-SY5Y and Kelly neuroblastoma cell lines, as well as the MDA-MB-231 and MCF-7 breast adenocarcinoma cell lines. Analogues 19 and 22 significantly reduced the cell viability of neuroblastoma cancer cells with micromolar potency and significant selectivity over normal cells. The quinoline hydrazide 22 also induced G1 cell cycle arrest, as well as upregulation of the p27kip1 cell cycle regulating protein.
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Affiliation(s)
- Murat Bingul
- School of Chemistry, The University of New South Wales Australia, Sydney, NSW 2052, Australia.
- Children's Cancer Institute Australia for Medical Research, Lowy Cancer Research Centre, The University of New South Wales Australia, Sydney, NSW 2031, Australia.
| | - Owen Tan
- Children's Cancer Institute Australia for Medical Research, Lowy Cancer Research Centre, The University of New South Wales Australia, Sydney, NSW 2031, Australia.
| | - Christopher R Gardner
- School of Chemistry, The University of New South Wales Australia, Sydney, NSW 2052, Australia.
- Children's Cancer Institute Australia for Medical Research, Lowy Cancer Research Centre, The University of New South Wales Australia, Sydney, NSW 2031, Australia.
| | - Selina K Sutton
- Children's Cancer Institute Australia for Medical Research, Lowy Cancer Research Centre, The University of New South Wales Australia, Sydney, NSW 2031, Australia.
| | - Greg M Arndt
- Children's Cancer Institute Australia for Medical Research, Lowy Cancer Research Centre, The University of New South Wales Australia, Sydney, NSW 2031, Australia.
- ACRF Drug Discovery Centre for Childhood Cancer, Children's Cancer Institute Australia for Medical Research, Lowy Cancer Research Centre, The University of New South Wales Australia, Sydney, NSW 2052, Australia.
| | - Glenn M Marshall
- Children's Cancer Institute Australia for Medical Research, Lowy Cancer Research Centre, The University of New South Wales Australia, Sydney, NSW 2031, Australia.
- Kids Cancer Centre, Sydney Children's Hospital, Randwick, NSW 2031, Australia.
| | - Belamy B Cheung
- Children's Cancer Institute Australia for Medical Research, Lowy Cancer Research Centre, The University of New South Wales Australia, Sydney, NSW 2031, Australia.
| | - Naresh Kumar
- School of Chemistry, The University of New South Wales Australia, Sydney, NSW 2052, Australia.
| | - David StC Black
- School of Chemistry, The University of New South Wales Australia, Sydney, NSW 2052, Australia.
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Chiaradonna F, Barozzi I, Miccolo C, Bucci G, Palorini R, Fornasari L, Botrugno OA, Pruneri G, Masullo M, Passafaro A, Galimberti VE, Fantin VR, Richon VM, Pece S, Viale G, Di Fiore PP, Draetta G, Pelicci PG, Minucci S, Chiocca S. Redox-Mediated Suberoylanilide Hydroxamic Acid Sensitivity in Breast Cancer. Antioxid Redox Signal 2015; 23:15-29. [PMID: 25897982 PMCID: PMC4492673 DOI: 10.1089/ars.2014.6189] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
AIMS Vorinostat (suberoylanilide hydroxamic acid; SAHA) is a histone deacetylase inhibitor (HDACi) approved in the clinics for the treatment of T-cell lymphoma and with the potential to be effective also in breast cancer. We investigated the responsiveness to SAHA in human breast primary tumors and cancer cell lines. RESULTS We observed a differential response to drug treatment in both human breast primary tumors and cancer cell lines. Gene expression analysis of the breast cancer cell lines revealed that genes involved in cell adhesion and redox pathways, especially glutathione metabolism, were differentially expressed in the cell lines resistant to SAHA compared with the sensitive ones, indicating their possible association with drug resistance mechanisms. Notably, such an association was also observed in breast primary tumors. Indeed, addition of buthionine sulfoximine (BSO), a compound capable of depleting cellular glutathione, significantly enhanced the cytotoxicity of SAHA in both breast cancer cell lines and primary breast tumors. INNOVATION We identify and validate transcriptional differences in genes involved in redox pathways, which include potential predictive markers of sensitivity to SAHA. CONCLUSION In breast cancer, it could be relevant to evaluate the expression of antioxidant genes that may favor tumor resistance as a factor to consider for potential clinical application and treatment with epigenetic drugs (HDACis).
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Affiliation(s)
- Ferdinando Chiaradonna
- 1 Department of Biotechnology and Biosciences, University of Milano-Bicocca , Milan, Italy .,2 SYSBIO Centre of Systems Biology , Milan, Italy
| | - Iros Barozzi
- 3 Department of Experimental Oncology, European Institute of Oncology , Milan, Italy
| | - Claudia Miccolo
- 3 Department of Experimental Oncology, European Institute of Oncology , Milan, Italy
| | - Gabriele Bucci
- 3 Department of Experimental Oncology, European Institute of Oncology , Milan, Italy
| | - Roberta Palorini
- 1 Department of Biotechnology and Biosciences, University of Milano-Bicocca , Milan, Italy .,2 SYSBIO Centre of Systems Biology , Milan, Italy
| | - Lorenzo Fornasari
- 3 Department of Experimental Oncology, European Institute of Oncology , Milan, Italy
| | - Oronza A Botrugno
- 3 Department of Experimental Oncology, European Institute of Oncology , Milan, Italy
| | - Giancarlo Pruneri
- 4 Department of Pathology, European Institute of Oncology , Milan, Italy
| | - Michele Masullo
- 4 Department of Pathology, European Institute of Oncology , Milan, Italy
| | - Alfonso Passafaro
- 3 Department of Experimental Oncology, European Institute of Oncology , Milan, Italy
| | | | - Valeria R Fantin
- 6 Oncology Research Unit, Pfizer Global Research and Development , La Jolla, California
| | | | - Salvatore Pece
- 3 Department of Experimental Oncology, European Institute of Oncology , Milan, Italy
| | - Giuseppe Viale
- 4 Department of Pathology, European Institute of Oncology , Milan, Italy
| | - Pier Paolo Di Fiore
- 3 Department of Experimental Oncology, European Institute of Oncology , Milan, Italy
| | - Giulio Draetta
- 8 Institute for Applied Cancer, The University of Texas MD Anderson Cancer Center Science , Houston, Texas
| | - Pier Giuseppe Pelicci
- 3 Department of Experimental Oncology, European Institute of Oncology , Milan, Italy
| | - Saverio Minucci
- 3 Department of Experimental Oncology, European Institute of Oncology , Milan, Italy .,9 Department of Biosciences, University of Milan , Milan, Italy
| | - Susanna Chiocca
- 3 Department of Experimental Oncology, European Institute of Oncology , Milan, Italy
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Bergadà L, Yeramian A, Sorolla A, Matias-Guiu X, Dolcet X. Antioxidants impair anti-tumoral effects of Vorinostat, but not anti-neoplastic effects of Vorinostat and caspase-8 downregulation. PLoS One 2014; 9:e92764. [PMID: 24651472 PMCID: PMC3961419 DOI: 10.1371/journal.pone.0092764] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2013] [Accepted: 02/26/2014] [Indexed: 11/18/2022] Open
Abstract
We have recently demonstrated that histone deacetylase inhibitor, Vorinostat, applied as a single therapy or in combination with caspase-8 downregulation exhibits high anti-tumoral activity on endometrial carcinoma cell lines. In the present study, we have assessed the signalling processes underlying anti-tumoral effects of Vorinostat. Increasing evidence suggests that reactive oxygen species are responsible for histone deacetylase inhibitor-induced cell killing. We have found that Vorinostat induces formation of reactive oxygen species and DNA damage. To investigate the role of oxidative stress as anti-neoplastic mechanism, we have evaluated the effects of different antioxidants (Bha, Nac and Tiron) on endometrial carcinoma cell line Ishikawa treated with Vorinostat. We show that Bha, Nac and Tiron markedly inhibited the cytotoxic effects of Vorinostat, increasing cell viability in vitro. We found that all three antioxidants did not inhibited accumulation of acetyl Histone H4, so that antioxidants did not inhibit Vorinostat activity. Finally, we have evaluated the effects of antioxidants on anti-tumoral activity of Vorinostat as monotherapy or in combination with caspase-8 downregulation in vivo. Interestingly, antioxidants blocked the reduction of tumour growth caused by Vorinostat, but they were unable to inhibit anti-tumoral activity of Vorinostat plus caspase-8 inhibition.
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Affiliation(s)
- Laura Bergadà
- Oncologic Pathology Group, Department de Ciències Mèdiques Bàsiques, Universitat de Lleida, Hospital Universitari Arnau de Vilanova, Institut de Recerca Biomèdica de Lleida, IRBLleida, Lleida, Spain
| | - Andree Yeramian
- Oncologic Pathology Group, Department de Ciències Mèdiques Bàsiques, Universitat de Lleida, Hospital Universitari Arnau de Vilanova, Institut de Recerca Biomèdica de Lleida, IRBLleida, Lleida, Spain
| | - Annabel Sorolla
- Oncologic Pathology Group, Department de Ciències Mèdiques Bàsiques, Universitat de Lleida, Hospital Universitari Arnau de Vilanova, Institut de Recerca Biomèdica de Lleida, IRBLleida, Lleida, Spain
| | - Xavier Matias-Guiu
- Oncologic Pathology Group, Department de Ciències Mèdiques Bàsiques, Universitat de Lleida, Hospital Universitari Arnau de Vilanova, Institut de Recerca Biomèdica de Lleida, IRBLleida, Lleida, Spain
| | - Xavier Dolcet
- Oncologic Pathology Group, Department de Ciències Mèdiques Bàsiques, Universitat de Lleida, Hospital Universitari Arnau de Vilanova, Institut de Recerca Biomèdica de Lleida, IRBLleida, Lleida, Spain
- * E-mail:
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Synergistic Anticancer Effects of Vorinostat and Epigallocatechin-3-Gallate against HuCC-T1 Human Cholangiocarcinoma Cells. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2013; 2013:185158. [PMID: 23864881 PMCID: PMC3706064 DOI: 10.1155/2013/185158] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Accepted: 05/28/2013] [Indexed: 12/30/2022]
Abstract
The aim of this study was to investigate the effect of the combination of vorinostat and epigallocatechin-3-gallate against HuCC-T1 human cholangiocarcinoma cells. A novel chemotherapy strategy is required as cholangiocarcinomas rarely respond to conventional chemotherapeutic agents. Both vorinostat and EGCG induce apoptosis and suppress invasion, migration, and angiogenesis of tumor cells. The combination of vorinostat and EGCG showed synergistic growth inhibitory effects and induced apoptosis in tumor cells. The Bax/Bcl-2 expression ratio and caspase-3 and -7 activity increased, but poly (ADP-ribose) polymerase expression decreased when compared to treatment with each agent alone. Furthermore, invasion, matrix metalloproteinase (MMP) expression, and migration of tumor cells decreased following treatment with the vorinostat and EGCG combination compared to those of vorinostat or EGCG alone. Tube length and junction number of human umbilical vein endothelial cells (HUVECs) decreased as well as vascular endothelial growth factor expression following vorinostat and EGCG combined treatment. These results indicate that the combination of vorinostat and EGCG had a synergistic effect on inhibiting tumor cell angiogenesis potential. We suggest that the combination of vorinostat and EGCG is a novel option for cholangiocarcinoma chemotherapy.
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Alzoubi KH, Khabour OF, Jaber AG, Al-Azzam SI, Mhaidat NM, Masadeh MM. Tempol prevents genotoxicity induced by vorinostat: role of oxidative DNA damage. Cytotechnology 2013; 66:449-55. [PMID: 23761013 DOI: 10.1007/s10616-013-9597-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Accepted: 06/03/2013] [Indexed: 12/14/2022] Open
Abstract
Vorinostat is a member of histone deacetylase inhibitors, which represents a new class of anticancer agents for the treatment of solid and hematological malignancies. Studies have shown that these drugs induce DNA damage in blood lymphocytes, which is proposed to be due to the generation of oxidative lesions. The increase in DNA damage is sometimes associated with risk of developing secondary cancer. Thus, finding a treatment that limits DNA damage caused by anticancer drugs would be beneficial. Tempol is a potent antioxidant that was shown to prevent DNA damage induced by radiation. In this study, we aimed to investigate the harmful effects of vorinostat on DNA damage, and the possible protective effects of tempol against this damage. For that, the spontaneous frequency of sister chromatid exchanges (SCEs), chromosomal aberrations (CAs), and 8-hydroxy-2-deoxy guanosine (8-OHdG) levels were measured in cultured human lymphocytes treated with vorinostat and/or tempol. The results showed that vorinostat significantly increases the frequency of SCEs, CAs and 8-OHdG levels in human lymphocytes as compared to control. These increases were normalized by the treatment of cells with tempol. In conclusion, vorinostat is genotoxic to lymphocytes, and this toxicity is reduced by tempol. Such results could set the stage for future studies investigating the possible usefulness of antioxidants co-treatment in preventing the genotoxicity of vorinostat when used as anticancer in human.
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Affiliation(s)
- Karem H Alzoubi
- Department of Clinical Pharmacy, Faculty of Pharmacy, Jordan University of Science and Technology, Irbid, 22110, Jordan,
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Wilson PM, Labonte MJ, Martin SC, Kuwahara ST, El-Khoueiry A, Lenz HJ, Ladner RD. Sustained inhibition of deacetylases is required for the antitumor activity of the histone deactylase inhibitors panobinostat and vorinostat in models of colorectal cancer. Invest New Drugs 2013; 31:845-57. [PMID: 23299388 DOI: 10.1007/s10637-012-9914-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Accepted: 12/06/2012] [Indexed: 12/20/2022]
Abstract
Despite compelling preclinical data in colorectal cancer (CRC), the efficacy of HDACIs has been disappointing in the clinic. The goal of this study was to evaluate the effectiveness of vorinostat and panobinostat in a dose- and exposure-dependent manner in order to better understand the dynamics of drug action and antitumor efficacy. In a standard 72 h drug exposure MTS assay, notable concentration-dependent antiproliferative effects were observed in the IC50 range of 1.2-2.8 μmol/L for vorinostat and 5.1-17.5 nmol/L for panobinostat. However, shorter clinically relevant exposures of 3 or 6 h failed to elicit any significant growth inhibition and in most cases a >24 h exposure to vorinostat or panobinostat was required to induce a sigmoidal dose-response. Similar results were observed in colony formation assays where ≥ 24 h of exposure was required to effectively reduce colony formation. Induction of acetyl-H3, acetyl-H4 and p21 by vorinostat were transient and rapidly reversed within 12 h of drug removal. In contrast, panobinostat-induced acetyl-H3, acetyl-H4, and p21 persisted for 48 h after an initial 3 h exposure. Treatment of HCT116 xenografts with panobinostat induced significant increases in acetyl-H3 and downregulation of thymidylate synthase after treatment. Although HDACIs exert both potent growth inhibition and cytotoxic effects when CRC cells were exposed to drug for ≥ 24 h, these cells demonstrate an inherent ability to survive HDACI concentrations and exposure times that exceed those clinically achievable. Continued efforts to develop novel HDACIs with improved pharmacokinetics/phamacodynamics, enhanced intratumoral delivery and class/isoform-specificity are needed to improve the therapeutic potential of HDACIs and HDACI-based combination regimens in solid tumors.
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Affiliation(s)
- Peter M Wilson
- Department of Pathology, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90089, USA
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Abstract
Prostate cancer is a commonly diagnosed cancer in men and a leading cause of cancer deaths. Whilst the underlying mechanisms leading to prostate cancer are still to be determined, it is evident that both genetic and epigenetic changes contribute to the development and progression of this disease. Epigenetic changes involving DNA hypo- and hypermethylation, altered histone modifications and more recently changes in microRNA expression have been detected at a range of genes associated with prostate cancer. Furthermore, there is evidence that particular epigenetic changes are associated with different stages of the disease. Whilst early detection can lead to effective treatment, and androgen deprivation therapy has a high response rate, many tumours develop towards hormone-refractory prostate cancer, for which there is no successful treatment. Reliable markers for early detection and more effective treatment strategies are, therefore, needed. Consequently, there is a considerable interest in the potential of epigenetic changes as markers or targets for therapy in prostate cancer. Epigenetic modifiers that demethylate DNA and inhibit histone deacetylases have recently been explored to reactivate silenced gene expression in cancer. However, further understanding of the mechanisms and the effects of chromatin modulation in prostate cancer are required. In this review, we examine the current literature on epigenetic changes associated with prostate cancer and discuss the potential use of epigenetic modifiers for treatment of this disease.
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