FOS and neoplasm: Given that IL-6 has been known to increase AR activity in castration-resistant prostate cancer [37], together, these molecule features of the prostate epithelium of the pbIL-6 mice endowed its neoplasia features and tumorigenic properties, which were further substantiated by elevated expression of oncogenes, such as c-Fos and k-Ras as measured by quantitative RT-PCR (Fig. 2c, d).