1
|
Etoposide and topoisomerase II inhibition for aggressive prostate cancer: Data from a translational study. Cancer Treat Res Commun 2020; 25:100221. [PMID: 33091733 DOI: 10.1016/j.ctarc.2020.100221] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 09/05/2020] [Accepted: 10/04/2020] [Indexed: 12/16/2022]
Abstract
BACKGROUND Etoposide phosphate (VP-16) is a topoisomerase 2 (TOP2) inhibitor that demonstrated activity in patients with metastatic castration-resistant prostate cancer (mCRPC). We investigated the sensitivity of prostate cancer (PCa) cells (LNCaP, 22Rv1, PC3, DU145, PDB and MDB) to VP-16 and the possible relationship between VP-16 activity and TOP2 expression. The activity of VP-16 was compared with that of docetaxel, enzalutamide and olaparib. The prevalence and clinical significance of TOP2 genetic and transcriptomic alterations was also explored in mCRPC. METHODS Cell cultures and crystal violet cell proliferation assays were performed. Specific antibodies were used in western blots analyses of cell protein extracts. Datasets were analyzed in cBioportal. RESULTS VP-16 was active in all PCa cell lines analyzed and demonstrated increased activity in PC3 and DU145 cells. VP-16 was more cytotoxic compared to the other treatments, except for LNCaP and 22Rv1, which were more sensitive to docetaxel. Maintenance of antiandrogen treatment in MDB and PDB increased sensitivity to VP-16, docetaxel and enzalutamide. TOP2A was found overexpressed in 22Rv1, DU145 and PC3, whereas TOP2B was overexpressed in 22Rv1 and PDB. In the mCRPC datasets analysis, TOP2A mRNA overexpression was associated with worse patients' prognosis, with the molecular features of neuroendocrine prostate cancer (NEPC) and with lower androgen receptor (AR) score. Patients overexpressing TOP2A mRNA were more likely to harbor RB1 loss. CONCLUSIONS Specific subpopulations of patients with aggressive variant prostate cancer (AVPC) could benefit from VP-16 treatment. TOP2A overexpression, rather than TOP2B, might be a good biomarker to predict response to VP-16.
Collapse
|
2
|
Kim EH, Cao D, Mahajan NP, Andriole GL, Mahajan K. ACK1-AR and AR-HOXB13 signaling axes: epigenetic regulation of lethal prostate cancers. NAR Cancer 2020; 2:zcaa018. [PMID: 32885168 PMCID: PMC7454006 DOI: 10.1093/narcan/zcaa018] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 07/22/2020] [Accepted: 08/13/2020] [Indexed: 12/24/2022] Open
Abstract
The androgen receptor (AR) is a critical transcription factor in prostate cancer (PC) pathogenesis. Its activity in malignant cells is dependent on interactions with a diverse set of co-regulators. These interactions fluctuate depending on androgen availability. For example, the androgen depletion increases the dependence of castration-resistant PCs (CRPCs) on the ACK1 and HOXB13 cell survival pathways. Activated ACK1, an oncogenic tyrosine kinase, phosphorylates cytosolic and nuclear proteins, thereby avoiding the inhibitory growth consequences of androgen depletion. Notably, ACK1-mediated phosphorylation of histone H4, which leads to epigenetic upregulation of AR expression, has emerged as a critical mechanism of CRPC resistance to anti-androgens. This resistance can be targeted using the ACK1-selective small-molecule kinase inhibitor (R)- 9b. CRPCs also deploy the bromodomain and extra-terminal domain protein BRD4 to epigenetically increase HOXB13 gene expression, which in turn activates the MYC target genes AURKA/AURKB. HOXB13 also facilitates ligand-independent recruitment of the AR splice variant AR-V7 to chromatin, compensating for the loss of the chromatin remodeling protein, CHD1, and restricting expression of the mitosis control gene HSPB8. These studies highlight the crosstalk between AR-ACK1 and AR-HOXB13 pathways as key mediators of CRPC recurrence.
Collapse
Affiliation(s)
- Eric H Kim
- Division of Urologic Surgery, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Dengfeng Cao
- Siteman Cancer Center, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Nupam P Mahajan
- Division of Urologic Surgery, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Gerald L Andriole
- Division of Urologic Surgery, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Kiran Mahajan
- Division of Urologic Surgery, Washington University in St. Louis, St. Louis, MO 63110, USA
| |
Collapse
|
3
|
Jo DW, Kim YK, Yun PY. The influence of p53 mutation status on the anti-cancer effect of cisplatin in oral squamous cell carcinoma cell lines. J Korean Assoc Oral Maxillofac Surg 2016; 42:337-344. [PMID: 28053903 PMCID: PMC5206238 DOI: 10.5125/jkaoms.2016.42.6.337] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 10/05/2016] [Accepted: 10/07/2016] [Indexed: 01/08/2023] Open
Abstract
Objectives The purpose of this study was to evaluate the anti-cancer activity of cisplatin by studying its effects on cell viability and identifying the mechanisms underlying the induction of cell cycle arrest and apoptosis on oral squamous cell carcinoma (OSCC) cell lines with varying p53 mutation status. Materials and Methods Three OSCC cell lines, YD-8 (p53 point mutation), YD-9 (p53 wild type), and YD-38 (p53 deletion) were used. To determine the cytotoxic effect of cisplatin, MTS assay was performed. The cell cycle alteration and apoptosis were analyzed using flow cytometry. Western blot analysis was used to detect the expression of cell cycle alteration- or apoptosis-related proteins as well as p53. Results Cisplatin showed a time- and dose-dependent anti-proliferative effect in all cell lines. Cisplatin induced G2/M cell accumulation in the three cell lines after treatment with 0.5 and 1.0 µg/mL of cisplatin for 48 hours. The proportion of annexin V-FITC-stained cells increased following treatment with cisplatin. The apoptotic proportion was lower in the YD-38 cell line than in the YD-9 or YD-8 cell lines. Also, immunoblotting analysis indicated that p53 and p21 were detected only in YD-8 and YD-9 cell lines after cisplatin treatment. Conclusion In this study, cisplatin showed anti-cancer effects via G2/M phase arrest and apoptosis, with some difference among OSCC cell lines. The mutation status of p53 might have influenced the difference observed among cell lines. Further studies on p53 mutation status are needed to understand the biological behavior and characteristics of OSCCs and to establish appropriate treatment.
Collapse
Affiliation(s)
- Deuk-Won Jo
- Department of Prosthodontics, Section of Dentistry, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Young-Kyun Kim
- Department of Oral and Maxillofacial Surgery, Section of Dentistry, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Pil-Young Yun
- Department of Oral and Maxillofacial Surgery, Section of Dentistry, Seoul National University Bundang Hospital, Seongnam, Korea
| |
Collapse
|
4
|
Souza TM, Rieswijk L, Beucken TVD, Kleinjans J, Jennen D. Persistent transcriptional responses show the involvement of feed-forward control in a repeated dose toxicity study. Toxicology 2016; 375:58-63. [PMID: 27765683 DOI: 10.1016/j.tox.2016.10.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 10/13/2016] [Accepted: 10/14/2016] [Indexed: 01/17/2023]
Abstract
Chemical carcinogenesis, albeit complex, often relies on modulation of transcription through activation or repression of key transcription factors. While analyzing extensive networks may hinder the biological interpretation, one may focus on dynamic network motifs, among which persistent feed-forward loops (FFLs) are known to chronically influence transcriptional programming. Here, to investigate the relevance a FFL-oriented approach in depth, we have focused on aflatoxin B1-induced transcriptomic alterations during distinct states of exposure (daily administration during 5days followed by a non-exposed period) of human hepatocytes, by exploring known interactions in human transcription. Several TF-coding genes were persistently deregulated after washout of AFB1. Oncogene MYC was identified as the prominent regulator and driver of many FFLs, among which a FFL comprising MYC/HIF1A was the most recurrent. The MYC/HIF1A FFL was also identified and validated in an independent set as the master regulator of metabolic alterations linked to initiation and progression of carcinogenesis, i.e. the Warburg effect, possibly as result of persistent intracellular alterations arising from AFB1 exposure (nuclear and mitochondrial DNA damage, oxidative stress, transcriptional activation by secondary messengers). In summary, our analysis shows the involvement of FFLs as modulators of gene expression suggestive of a carcinogenic potential even after termination of exposure.
Collapse
Affiliation(s)
- Terezinha M Souza
- Department of Toxicogenomics, Maastricht University, Maastricht, 6229 ER, The Netherlands.
| | - Linda Rieswijk
- Department of Toxicogenomics, Maastricht University, Maastricht, 6229 ER, The Netherlands.
| | - Twan van den Beucken
- Department of Toxicogenomics, Maastricht University, Maastricht, 6229 ER, The Netherlands.
| | - Jos Kleinjans
- Department of Toxicogenomics, Maastricht University, Maastricht, 6229 ER, The Netherlands.
| | - Danyel Jennen
- Department of Toxicogenomics, Maastricht University, Maastricht, 6229 ER, The Netherlands.
| |
Collapse
|
5
|
Rebello RJ, Kusnadi E, Cameron DP, Pearson HB, Lesmana A, Devlin JR, Drygin D, Clark AK, Porter L, Pedersen J, Sandhu S, Risbridger GP, Pearson RB, Hannan RD, Furic L. The Dual Inhibition of RNA Pol I Transcription and PIM Kinase as a New Therapeutic Approach to Treat Advanced Prostate Cancer. Clin Cancer Res 2016; 22:5539-5552. [PMID: 27486174 DOI: 10.1158/1078-0432.ccr-16-0124] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 07/15/2016] [Accepted: 07/21/2016] [Indexed: 11/16/2022]
Abstract
PURPOSE The MYC oncogene is frequently overexpressed in prostate cancer. Upregulation of ribosome biogenesis and function is characteristic of MYC-driven tumors. In addition, PIM kinases activate MYC signaling and mRNA translation in prostate cancer and cooperate with MYC to accelerate tumorigenesis. Here, we investigate the efficacy of a single and dual approach targeting ribosome biogenesis and function to treat prostate cancer. EXPERIMENTAL DESIGN The inhibition of ribosomal RNA (rRNA) synthesis with CX-5461, a potent, selective, and orally bioavailable inhibitor of RNA polymerase I (Pol I) transcription, has been successfully exploited therapeutically but only in models of hematologic malignancy. CX-5461 and CX-6258, a pan-PIM kinase inhibitor, were tested alone and in combination in prostate cancer cell lines, in Hi-MYC- and PTEN-deficient mouse models and in patient-derived xenografts (PDX) of metastatic tissue obtained from a patient with castration-resistant prostate cancer. RESULTS CX-5461 inhibited anchorage-independent growth and induced cell-cycle arrest in prostate cancer cell lines at nanomolar concentrations. Oral administration of 50 mg/kg CX-5461 induced TP53 expression and activity and reduced proliferation (MKI67) and invasion (loss of ductal actin) in Hi-MYC tumors, but not in PTEN-null (low MYC) tumors. While 100 mg/kg CX-6258 showed limited effect alone, its combination with CX-5461 further suppressed proliferation and dramatically reduced large invasive lesions in both models. This rational combination strategy significantly inhibited proliferation and induced cell death in PDX of prostate cancer. CONCLUSIONS Our results demonstrate preclinical efficacy of targeting the ribosome at multiple levels and provide a new approach for the treatment of prostate cancer. Clin Cancer Res; 22(22); 5539-52. ©2016 AACR.
Collapse
Affiliation(s)
- Richard J Rebello
- Cancer Program, Biomedicine Discovery Institute and Department of Anatomy & Developmental Biology, Monash University, Victoria, Australia
| | - Eric Kusnadi
- Oncogenic Signaling and Growth Control Program, Peter MacCallum Cancer Centre, St Andrews Place, East Melbourne, Victoria, Australia
| | - Donald P Cameron
- Oncogenic Signaling and Growth Control Program, Peter MacCallum Cancer Centre, St Andrews Place, East Melbourne, Victoria, Australia.,Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Helen B Pearson
- Oncogenic Signaling and Growth Control Program, Peter MacCallum Cancer Centre, St Andrews Place, East Melbourne, Victoria, Australia
| | - Analia Lesmana
- Oncogenic Signaling and Growth Control Program, Peter MacCallum Cancer Centre, St Andrews Place, East Melbourne, Victoria, Australia
| | - Jennifer R Devlin
- Oncogenic Signaling and Growth Control Program, Peter MacCallum Cancer Centre, St Andrews Place, East Melbourne, Victoria, Australia
| | | | - Ashlee K Clark
- Cancer Program, Biomedicine Discovery Institute and Department of Anatomy & Developmental Biology, Monash University, Victoria, Australia
| | - Laura Porter
- Cancer Program, Biomedicine Discovery Institute and Department of Anatomy & Developmental Biology, Monash University, Victoria, Australia
| | | | - Shahneen Sandhu
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia
| | - Gail P Risbridger
- Cancer Program, Biomedicine Discovery Institute and Department of Anatomy & Developmental Biology, Monash University, Victoria, Australia
| | - Richard B Pearson
- Oncogenic Signaling and Growth Control Program, Peter MacCallum Cancer Centre, St Andrews Place, East Melbourne, Victoria, Australia. .,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia.,Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, Australia.,Department of Biochemistry and Molecular Biology, Monash University, Victoria, Australia
| | - Ross D Hannan
- Oncogenic Signaling and Growth Control Program, Peter MacCallum Cancer Centre, St Andrews Place, East Melbourne, Victoria, Australia. .,Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University, Canberra, Australia.,Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria, Australia.,Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, Australia.,Department of Biochemistry and Molecular Biology, Monash University, Victoria, Australia.,School of Biomedical Sciences, University of Queensland, Brisbane, Queensland, Australia
| | - Luc Furic
- Cancer Program, Biomedicine Discovery Institute and Department of Anatomy & Developmental Biology, Monash University, Victoria, Australia.
| |
Collapse
|
6
|
Chemopreventive effect of Annona muricata on DMBA-induced cell proliferation in the breast tissues of female albino mice. EGYPTIAN JOURNAL OF MEDICAL HUMAN GENETICS 2014. [DOI: 10.1016/j.ejmhg.2014.05.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
|
7
|
Ta HQ, Gioeli D. The convergence of DNA damage checkpoint pathways and androgen receptor signaling in prostate cancer. Endocr Relat Cancer 2014; 21:R395-407. [PMID: 25096064 PMCID: PMC4382101 DOI: 10.1530/erc-14-0217] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
It is increasingly clear that castration-resistant prostate cancer (PCa) is dependent on the androgen receptor (AR). This has led to the use of anti-androgen therapies that reduce endogenous steroid hormone production as well as the use of AR antagonists. However, the AR does not act in isolation and integrates with a milieu of cell-signaling proteins to affect cell biology. It is well established that cancer is a genetic disease resulting from the accumulation of mutations and chromosomal translocations that enables cancer cells to survive, proliferate, and disseminate. To maintain genomic integrity, there exists conserved checkpoint signaling pathways to facilitate cell cycle delay, DNA repair, and/or apoptosis in response to DNA damage. The AR interacts with, affects, and is affected by these DNA damage-response proteins. This review will focus on the connections between checkpoint signaling and the AR in PCa. We will describe what is known about how components of checkpoint signaling regulate AR activity and what questions still face the field.
Collapse
Affiliation(s)
- Huy Q Ta
- Department of MicrobiologyImmunology, and Cancer BiologyUVA Cancer CenterUniversity of Virginia, PO Box 800734, Charlottesville, Virginia 22908, USA
| | - Daniel Gioeli
- Department of MicrobiologyImmunology, and Cancer BiologyUVA Cancer CenterUniversity of Virginia, PO Box 800734, Charlottesville, Virginia 22908, USA Department of MicrobiologyImmunology, and Cancer BiologyUVA Cancer CenterUniversity of Virginia, PO Box 800734, Charlottesville, Virginia 22908, USA
| |
Collapse
|
8
|
Chiang KC, Tsui KH, Chung LC, Yeh CN, Feng TH, Chen WT, Chang PL, Chiang HY, Juang HH. Cisplatin modulates B-cell translocation gene 2 to attenuate cell proliferation of prostate carcinoma cells in both p53-dependent and p53-independent pathways. Sci Rep 2014; 4:5511. [PMID: 24981574 PMCID: PMC4076686 DOI: 10.1038/srep05511] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Accepted: 06/11/2014] [Indexed: 12/29/2022] Open
Abstract
Cisplatin is a widely used anti-cancer drug. The B-cell translocation gene 2 (BTG2) is involved in the cell cycle transition regulation. We evaluated the cisplatin effects on prostate cancer cell proliferation and the expressions of BTG2, p53, androgen receptor (AR) and prostate specific antigen (PSA) in prostate carcinoma, p53 wild-type LNCaP or p53-null PC-3, cells. Cisplatin treatments attenuated cell prostate cancer cell growth through inducing Go/G1 cell cycle arrest in lower concentration and apoptosis at higher dosage. Cisplatin treatments enhanced p53 and BTG2 expression, repressed AR and PSA expression, and blocked the activation of androgen on the PSA secretion in LNCaP cells. BTG2 knockdown in LNCaP cells attenuated cisplatin-mediated growth inhibition. Cisplatin enhanced BTG2 gene expression dependent on the DNA fragment located within -173 to -82 upstream of BTG2 translation initiation site in prostate cancer cells. Mutation of the p53 response element from GGGCAGAGCCC to GGGCACC or mutation of the NFκB response element from GGAAAGTCC to GGAAAGGAA by site-directed mutagenesis abolished the stimulation of cisplatin on the BTG2 promoter activity in LNCaP or PC-3 cells, respectively. Our results indicated that cisplatin attenuates prostate cancer cell proliferation partly mediated by upregulation of BTG2 through the p53-dependent pathway or p53-independent NFκB pathway.
Collapse
Affiliation(s)
- Kun-Chun Chiang
- Department of General Surgery, Chang Gung Memorial Hospital, Keelung, Taiwan, ROC
- These authors contributed equally to this work
| | - Ke-Hung Tsui
- Department of Urology, Chang Gung Memorial Hospital, Kwei-Shan, Tao-Yuan, Taiwan, ROC
- These authors contributed equally to this work
| | - Li-Chuan Chung
- Department of Anatomy, College of Medicine, Chang Gung University, Kwei-Shan, Tao-Yuan, Taiwan, ROC
| | - Chun-Nan Yeh
- Department of General Surgery, Chang Gung Memorial Hospital, Kwei-Shan, Tao-Yuan, Taiwan, ROC
| | - Tsui-Hsia Feng
- School of Nursing, College of Medicine, Chang Gung University, Kwei-Shan, Tao-Yuan, Taiwan, ROC
| | - Wen-Tsung Chen
- National Kaohsiung University of Hospitality and Tourism, Hsiao-Kang, Kaohsiung Taiwan R.O.C
| | - Phei-Lang Chang
- Department of Urology, Chang Gung Memorial Hospital, Kwei-Shan, Tao-Yuan, Taiwan, ROC
| | - Hou-Yu Chiang
- Department of Anatomy, College of Medicine, Chang Gung University, Kwei-Shan, Tao-Yuan, Taiwan, ROC
| | - Horng-Heng Juang
- Department of Anatomy, College of Medicine, Chang Gung University, Kwei-Shan, Tao-Yuan, Taiwan, ROC
| |
Collapse
|
9
|
Yang F, Nickols NG, Li BC, Szablowski JO, Hamilton SR, Meier JL, Wang CM, Dervan PB. Animal toxicity of hairpin pyrrole-imidazole polyamides varies with the turn unit. J Med Chem 2013; 56:7449-57. [PMID: 24015881 PMCID: PMC3788622 DOI: 10.1021/jm401100s] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
![]()
A hairpin
pyrrole-imidazole polyamide (1) targeted
to the androgen receptor consensus half-site was found to exert antitumor
effects against prostate cancer xenografts. A previous animal study
showed that 1, which has a chiral amine at the α-position
of the γ-aminobutyric acid turn (γ-turn), did not exhibit
toxicity at doses less than 10 mg/kg. In the same study, a polyamide
with an acetamide at the β-position of the γ-turn resulted
in animal morbidity at 2.3 mg/kg. To identify structural motifs that
cause animal toxicity, we synthesized polyamides 1–4 with variations at the α- and β-positions in
the γ-turn. Weight loss, histopathology, and serum chemistry
were analyzed in mice post-treatment. While serum concentration was
similar for all four polyamides after injection, dose-limiting liver
toxicity was only observed for three polyamides. Polyamide 3, with an α-acetamide, caused no significant evidence of rodent
toxicity and retains activity against LNCaP xenografts.
Collapse
Affiliation(s)
- Fei Yang
- Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California 91125, United States
| | | | | | | | | | | | | | | |
Collapse
|
10
|
Hsiao KY, Mizzen CA. Histone H4 deacetylation facilitates 53BP1 DNA damage signaling and double-strand break repair. J Mol Cell Biol 2013; 5:157-65. [PMID: 23329852 DOI: 10.1093/jmcb/mjs066] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
53BP1 and other DNA damage response (DDR) proteins form foci at double-strand breaks (DSBs) which promote their repair by nonhomologous end joining (NHEJ). Focal accumulation of 53BP1 depends on the specific interaction of its tandem Tudor domain with dimethylated lysine 20 in histone H4 (H4K20me2). How 53BP1 foci dynamics are regulated is unclear since H4K20me2 is highly abundant, established largely in the absence of DNA damage, and uncertainty exists about the roles of candidate H4K20 methyltransferases in 53BP1 foci formation. Here, we show that 53BP1 foci assemble primarily on H4K20me2 established prior to DNA damage by the SETD8 and SUV420 methyltransferases rather than de novo H4K20 methylation mediated by MMSET/WHSC1. Moreover, we define a novel role for H4K16 acetylation in regulating 53BP1 foci dynamics. Concurrent acetylation at H4K16 antagonizes 53BP1 binding to extant H4K20me2 until DSBs elicit transient, localized H4 deacetylation that facilitates 53BP1 foci formation and NHEJ, and is associated with global repression of gene transcription. Our findings demonstrate that rapid induction of H4 deacetylation by DSBs affects multiple aspects of the DDR, and also suggest that antagonism of 53BP1 binding to H4K20me2 by H4K16 hyperacetylation may contribute to the efficacy of histone deacetylase inhibitors for cancer therapy.
Collapse
Affiliation(s)
- Kuei-Yang Hsiao
- Department of Molecular and Integrative Physiology, University of Illinois, Urbana, IL 61801, USA
| | | |
Collapse
|
11
|
The stress response mediator ATF3 represses androgen signaling by binding the androgen receptor. Mol Cell Biol 2012; 32:3190-202. [PMID: 22665497 DOI: 10.1128/mcb.00159-12] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Activating transcription factor 3 (ATF3) is a common mediator of cellular stress response signaling and is often aberrantly expressed in prostate cancer. We report here that ATF3 can directly bind the androgen receptor (AR) and consequently repress AR-mediated gene expression. The ATF3-AR interaction requires the leucine zipper domain of ATF3 that independently binds the DNA-binding and ligand-binding domains of AR, and the interaction prevents AR from binding to cis-acting elements required for expression of androgen-dependent genes while inhibiting the AR N- and C-terminal interaction. The functional consequences of the loss of ATF3 expression include increased transcription of androgen-dependent genes in prostate cancer cells that correlates with increased ability to grow in low-androgen-containing medium and increased proliferative activity of the prostate epithelium in ATF3 knockout mice that is associated with prostatic hyperplasia. Our results thus demonstrate that ATF3 is a novel repressor of androgen signaling that can inhibit AR functions, allowing prostate cells to restore homeostasis and maintain integrity in the face of a broad spectrum of intrinsic and environmental insults.
Collapse
|
12
|
Elattar A, Warburton KG, Mukhopadhyay A, Freer RM, Shaheen F, Cross P, Plummer ER, Robson CN, Edmondson RJ. Androgen receptor expression is a biological marker for androgen sensitivity in high grade serous epithelial ovarian cancer. Gynecol Oncol 2012; 124:142-7. [DOI: 10.1016/j.ygyno.2011.09.004] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Revised: 09/01/2011] [Accepted: 09/03/2011] [Indexed: 01/12/2023]
|
13
|
Sex dimorphism in antitumor response of chemotherapeutic drug cisplatin in a murine host-bearing a T-cell lymphoma. Anticancer Drugs 2008; 19:583-92. [PMID: 18525317 DOI: 10.1097/cad.0b013e3282fb97bf] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Previously we have demonstrated that in-vivo growth of a murine T-cell lymphoma of spontaneous origin designated as Dalton's lymphoma (DL) shows sex dimorphism (J Rep Immunol 2005; 65:17-32). It remained unclear, however, if DL growth in female and male tumor-bearing hosts also shows a sex-dependent differential susceptibility to the antitumor action of cancer chemotherapeutic drugs. In this study we have demonstrated that in-vivo administration of anticancer drugs: cisplatin or doxorubicin to the DL-bearing host results in a sex-dependent different antitumor activity of the drugs, causing a sex dimorphism in the antitumor response of the drugs with respect to tumor growth inhibition. The antitumor effect of both drugs was found to be better in male tumor-bearing hosts compared with female tumor-bearing hosts. The study also shows that DL cells obtained from male and female tumor-bearing hosts display a differential growth response to following treatment with cisplatin in vitro. Cell growth regulatory proteins: interleukin-2, interferon-gamma, tumor growth factor-beta, p53, caspase-activated DNase, vascular endothelial growth factor, and interleukin-2 receptor were found to be involved in the observed sex-specific response of DL cells to the antitumor action of cisplatin. Moreover, gonadal hormones: androgen, estrogen, and their specific antagonists flutamide and tamoxifen were found to directly modulate the cytotoxicity of cisplatin against DL cells in vitro. This study, therefore, suggests for the first time that the efficacy of cancer chemotherapeutic may vary in a sex-specific manner in a host-bearing a T-cell lymphoma.
Collapse
|
14
|
Zender L, Kubicka S. Androgen receptor and hepatocarcinogenesis: what do we learn from HCC mouse models? Gastroenterology 2008; 135:738-40. [PMID: 18692055 DOI: 10.1053/j.gastro.2008.07.034] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
|
15
|
Inhibition of apoptosis in prostate cancer cells by androgens is mediated through downregulation of c-Jun N-terminal kinase activation. Neoplasia 2008; 10:418-28. [PMID: 18472959 DOI: 10.1593/neo.07985] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2007] [Revised: 02/19/2008] [Accepted: 02/20/2008] [Indexed: 11/18/2022] Open
Abstract
Androgen deprivation induces the regression of prostate tumors mainly due to an increase in the apoptosis rate; however, the molecular mechanisms underlying the antiapoptotic actions of androgens are not completely understood. We have studied the antiapoptotic effects of androgens in prostate cancer cells exposed to different proapoptotic stimuli. Terminal deoxynucleotidyl transferase-mediated nick-end labeling and nuclear fragmentation analyses demonstrated that androgens protect LNCaP prostate cancer cells from apoptosis induced by thapsigargin, the phorbol ester 12-O-tetradecanoyl-13-phorbol-acetate, or UV irradiation. These three stimuli require the activation of the c-Jun N-terminal kinase (JNK) pathway to induce apoptosis and in all three cases, androgen treatment blocks JNK activation. Interestingly, okadaic acid, a phosphatase inhibitor that causes apoptosis in LNCaP cells, induces JNK activation that is also inhibited by androgens. Actinomycin D, the antiandrogen bicalutamide or specific androgen receptor (AR) knockdown by small interfering RNA all blocked the inhibition of JNK activation mediated by androgens indicating that this activity requires AR-dependent transcriptional activation. These data suggest that the crosstalk between AR and JNK pathways may have important implications in prostate cancer progression and may provide targets for the development of new therapies.
Collapse
|
16
|
Anti-histone acetyltransferase activity from allspice extracts inhibits androgen receptor-dependent prostate cancer cell growth. Biosci Biotechnol Biochem 2007; 71:2712-9. [PMID: 17986787 DOI: 10.1271/bbb.70306] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Histone acetylation depends on the activity of two enzyme families, histone acetyltransferase (HAT) and deacetylase (HDAC). In this study, we screened various plant extracts to find potent HAT inhibitors. Hot water extracts of allspice inhibited HAT activity, especially p300 and CBP (40% at 100 microg/ml). The mRNA levels of two androgen receptor (AR) regulated genes, PSA and TSC22, decreased with allspice treatment (100 microg/ml). Importantly, in IP western analysis, AR acetylation was dramatically decreased by allspice treatment.Furthermore, chromatin immunoprecipitation indicated that the acetylation of histone H3 in the PSA and B2M promoter regions was also repressed. Finally, allspice treatment reduced the growth of human prostate cancer cells, LNCaP (50% growth inhibition at 200 microg/ml). Taken together, our data indicate that the potent HAT inhibitory activity of allspice reduced AR and histone acetylation and led to decreased transcription of AR target genes, resulting in inhibition of prostate cancer cell growth.
Collapse
|
17
|
Gupta V, Singh SM. Gender dimorphism in the myeloid differentiation of bone marrow precursor cells in a murine host bearing a T cell lymphoma. J Reprod Immunol 2007; 74:90-102. [PMID: 17275917 DOI: 10.1016/j.jri.2007.01.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2006] [Revised: 11/24/2006] [Accepted: 01/02/2007] [Indexed: 12/11/2022]
Abstract
Little information is available regarding the existence of gender dimorphism of tumor growth for most types of tumors. In a previous report we have demonstrated the existence of gender dimorphism in the growth of a murine T cell lymphoma, designated as Dalton's lymphoma (DL); moreover, tumor-associated macrophages (TAM) were found to play a central role in the manifestation of gender dimorphism observed in the growth of this T cell lymphoma. In view of these observations, the present investigation was undertaken to study if gender dimorphism in the growth of a T cell tumor also could be associated with a gender-dependent differential myelopoiesis of bone marrow cells. We have demonstrated the existence of a gender dimorphism in the proliferation, apoptosis and myeloid differentiation of bone marrow cells obtained from male and female tumor-bearing hosts. Androgen and estrogen were found to alter directly the growth properties of bone marrow cells, as also determined by the use of receptor antagonists of these hormones, flutamide and tamoxifen. Bone marrow cells of male and female tumor-bearing hosts also showed a differential expression of the cell cycle and apoptosis regulatory protein p53 and macrophage-colony stimulating factor (M-CSF) genes. Bone marrow cells of male tumor-bearing hosts showed a predominant differentiation in the macrophage lineage whereas those of female tumor-bearing mice were in the granulocyte lineage. Bone marrow-derived macrophages (BMDM) from male and female tumor-bearing mice also showed the existence of gender dimorphism with respect to their differentiation and activation. These observations are of clinical significance with respect to understanding of the host-tumor relationship at the level of gender dimorphism of myelopoiesis.
Collapse
Affiliation(s)
- Vivekanand Gupta
- School of Biotechnology, Banaras Hindu University, Varanasi 221005, India
| | | |
Collapse
|