Targeting DNA Damage Response in Prostate Cancer by Inhibiting Androgen Receptor-CDC6-ATR-Chk1 Signaling

Cell Reports

Ganiraju C. Manyam¹  Bradley Broom¹  Guang Yang²  Wei Zhang²  Sanghee Park²  Xuemei Zuo²  Jian H. Song²  Timothy C. Thompson²  Shuhua Li²  Gary E. Gallick²  Nora Navone²  Likun Li²  Paul G. Corn²  Styliani Karanika²  Theodoros Karantanos²  Ana M. Aparicio²  Jianxiang Wang²  Sankar N. Maity²  Patricia Troncoso³ 

[1] Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77230, USA;Department of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA;Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA;

关键词: androgen receptor;    CDC6;    Chk1;    ATR;    TOPBP1;    DNA damage;    prostate cancer;    enzalutamide;    AZD7762;   

DOI  :  10.1016/j.celrep.2017.01.072

来源: DOAJ

【 摘 要 】

Cell division cycle 6 (CDC6), an androgen receptor (AR) target gene, is implicated in regulating DNA replication and checkpoint mechanisms. CDC6 expression is increased during prostate cancer (PCa) progression and positively correlates with AR in PCa tissues. AR or CDC6 knockdown, together with AZD7762, a Chk1/2 inhibitor, results in decreased TopBP1-ATR-Chk1 signaling and markedly increased ataxia-telangiectasia-mutated (ATM) phosphorylation, a biomarker of DNA damage, and synergistically increases treatment efficacy. Combination treatment with the AR signaling inhibitor enzalutamide (ENZ) and the Chk1/2 inhibitor AZD7762 demonstrates synergy with regard to inhibition of AR-CDC6-ATR-Chk1 signaling, ATM phosphorylation induction, and apoptosis in VCaP (mutant p53) and LNCaP-C4-2b (wild-type p53) cells. CDC6 overexpression significantly reduced ENZ- and AZD7762-induced apoptosis. Additive or synergistic therapeutic activities are demonstrated in AR-positive animal xenograft models. These findings have important clinical implications, since they introduce a therapeutic strategy for AR-positive, metastatic, castration-resistant PCa, regardless of p53 status, through targeting AR-CDC6-ATR-Chk1 signaling.

【 授权许可】

Unknown