Sensitization of neuroendocrine prostate cancer by RRx-001.

280Background: RRx-001 is a first-in-class dinitroazetidine nontoxic anticancer agent. Its actions include upregulation of oxidative stress, depletion of GSH and NADPH, anti-angiogenesis, epigenetic modulation and induction of viral mimicry. In a phase II clinical study (NCT02489903), RRx-001 reversed resistance to reintroduced platinum doublets in small cell lung cancer (SCLC) and other tumor types. RRx001 demonstrated clinical activity with a complete metabolic response of metastatic castration-resistant neuroendocrine prostate cancer (NEPC) after treatment with RRx-001 and reintroduced platinum doublets. Here, we used a preclinical model to further investigate RRx-001 sensitization of NEPC to platinum therapy. Methods: NCI-H660 spheroids were pre-treated with 1 mM RRx-001 or vehicle prior to treatment with carboplatin or docetaxel and cell proliferation was assessed. Cells were also pre-treated with both 1 mM RRx-001 and 10 mM N-acetyl cysteine (NAC) or 1 mM Buthionine-S,R-sulfoximine (BSO) to investig...