Docetaxel Followed by Provenge in Metastatic Prostate Cancer

This clinical study will evaluate the role of combination therapy of docetaxel followed by Provenge for patients with metastatic castration-resistant prostate cancer (CRPC, (prostate cancer that is resistant to medical or surgical treatments that lower testosterone). The purpose of this study is to look at the combination therapy of docetaxel followed by Provenge to correlate the immunological biomarkers with clinical results for therapy. Biomarkers are genes, proteins and other molecules that affect how cancer cells grow, multiply, die and respond to other compounds in the body. The study drugs are approved by the Food and Drug Administration (FDA). Treatment will be administered on an outpatient basis. Patients will receive 6 cycles of docetaxel followed by Provenge. Docetaxel is an antineoplastic (chemotherapy that affects cancer cell growth) agent. Docetaxel dose of 75 mg/m2 will be given intravenously as a 1-hour infusion every 21 days on Day 1 for 6 cycles. Provenge is an immunotherapy (vaccine made from patient's own blood cells) that reprograms immune cells to attack cancer. A course of therapy consists of three doses of Provenge administered at 2-week intervals. The strategy aims to determine whether cytokine production and T cell infiltration of tumor cells could favor regression using a combination of chemotherapy plus vaccine. Tissue endpoints will include biopsies prior to first chemotherapy and first vaccine therapy and at the end of each therapy. Prostate cancer tissue infiltrates will be studied for expression of CD3, CD4, CD8, CD25/FOX3P, CD56, CTLA-4, PD-1, and Ki67. Additional immunological endpoints will be secondary antigen spread and various cytokine biomarkers.