Prostate cancer is one of the leading malignancies in adult males worldwide and existing therapies often result in treatment failure and emergence of castration resistant prostate cancer (CRPC). Outcome of some recent clinical trials highlighted the benefit of Docetaxel as a part of initial therapy in CRPC. However, a significant number of patients still remain chemoresistant. Context dependent response profiling using a clinically oriented functional platform would further improve this scenario. Here, we elucidated the role of different immune cells and type 1 and type 2 cytokines in improving Docetaxel sensitivity to prostatic carcinoma. We tested Docetaxel sensitivity in prostate tumors (n = 10) using CANScriptTM platform, a personalized next generation functional testing tool (Majumder B et al. Nat. Commun 2015, Goldman A et al. Nat. Commun. 2015). Of these 10 tumors, 4 were found to be sensitive to Docetaxel and 6 were insensitive. The immune profiling of these tumors suggested that despite preferential CD45, CD8 and CD4 levels in majority of the responders both responders and non responders display modest numbers at baseline. We also observed similar heterogeneity in CD69 (T cell activation marker) in these two groups. Altered expression of cytokines was observed in Docetaxel sensitive and resistant tumors upon their co-culture with peripheral blood mononuclear cells (PBMC), suggesting a defined role of these cytokines in Docetaxel response. We extended the study further by testing the efficacy of PD-1/ PD-L1 inhibitors in Docetaxel resistant tumors. Our results provide the basis for validation of immune phenotypes and cytokines as therapeutic response biomarkers in Docetaxel treated prostatic tumors.

1. Majumder B et al. Nat. Commun.6:6169 (2015).

2. Goldman A et al. Nat. Commun. 6:6139 (2015).

Citation Format: Debapriya G. Mehrotra, Nilesh Brijwani, Biplab Tewary, Vasathkumar Sekar, Abhishek Krishnan, Dency D. Pinto, Muthusamy Oliyarasi, Biswanath Majumder, Saravanan Thiyagarajan, Padhma Radhakrishnan, Pradip K. Majumder. Immunomodulating cytokine profiling of docetaxel-treated human prostate cancer specimens. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5121.