1
|
Wang S, Gilbreath C, Kollipara RK, Sonavane R, Huo X, Yenerall P, Das A, Ma S, Raj GV, Kittler R. Mithramycin suppresses DNA damage repair via targeting androgen receptor in prostate cancer. Cancer Lett 2020; 488:40-49. [PMID: 32485222 DOI: 10.1016/j.canlet.2020.05.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 04/22/2020] [Accepted: 05/21/2020] [Indexed: 01/04/2023]
Abstract
The dependency of prostate cancer (PCa) growth on androgen receptor (AR) signaling has been harnessed to develop first-line therapies for high-risk localized and metastatic PCa treatment. However, the occurrence of aberrant expression, mutated or splice variants of AR confers resistance to androgen ablation therapy (ADT), radiotherapy or chemotherapy in AR-positive PCa. Therapeutic strategies that effectively inhibit the expression and/or transcriptional activity of full-length AR, mutated AR and AR splice variants have remained elusive. In this study, we report that mithramycin (MTM), an antineoplastic antibiotic, suppresses cell proliferation and exhibits dual inhibitory effects on expression and transcriptional activity of AR and AR splice variants. MTM blocks AR recruitment to its genomic targets by occupying AR enhancers and causes downregulation of AR target genes, which includes key DNA repair factors in DNA damage repair (DDR). We show that MTM significantly impairs DDR and enhances the effectiveness of ionizing radiation or the radiomimetic agent Bleomycin in PCa. Thus, the combination of MTM treatment with RT or radiomimetic agents, such as bleomycin, may present a novel effective therapeutic strategy for patients with high-risk, clinically localized PCa.
Collapse
Affiliation(s)
- Shan Wang
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX, USA; Department of Urology, University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA.
| | - Collin Gilbreath
- Department of Urology, University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA
| | - Rahul K Kollipara
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Rajni Sonavane
- Department of Urology, University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA
| | - Xiaofang Huo
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Paul Yenerall
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX, USA; Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA
| | - Amit Das
- Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA
| | - Shihong Ma
- Department of Urology, University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA
| | - Ganesh V Raj
- Department of Urology, University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA
| | - Ralf Kittler
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX, USA; Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA; Department of Pharmacology, University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA; Green Center for Reproductive Biology Sciences, University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA.
| |
Collapse
|