LAUSR

Androgen receptor (AR) signaling plays a key role in the progression of prostate cancer and androgen deprivation therapy (ADT) is one the standard of care for men with advanced prostate cancer. However, AR also exerts effects on androgen responsive tissues and accumulating data indicates that AR is implicated in influencing gut flora. Commensal bacteria are essential for maintaining a healthy immune system which plays a major role in cancer surveillance. Moreover, cancer is known to promote commensal dysbiosis which can further impair immune function. Here, we investigate associations between commensal fecal bacteria and androgen deprivation in an immunocompetent transgenic mouse model of Pten-deficient prostate cancer. 16S rRNA amplicon sequencing was used to comprehensive profile and compare the fecal microbiomes of bearing conditional Pten-knockout mice with those of mice 5 weeks after surgical castration. Tumor burden in surgically castrated mice was significantly lower compared to that of intact mice, 57.45%, P Citation Format: Marco A. De Velasco, Kazuko Sakai, Yurie Kura, Eri Banno, Naomi Ando, Noriko Sako, Nobutaka Shimizu, Kazutoshi Fujita, Masahiro Nozawa, Kazuhiro Yoshimura, Kazuto Nishio, Hirotsugu Uemura. Correlates of androgen deprivation and gut microbiome in mouse Pten-deficient prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1781.