Accumulating evidence demonstrated that IRE1α-XBP1 pathway plays a critical role in various cancers, IRE1α-XBP1 pathway was found playing an important role in cell proliferation, tumor progression and invasion in colorectal carcinoma (11), melanoma (12), hepatocellular carcinoma (13) and prostate cancer (14). This evidence concerns the gene XBP1 and Familial prostate cancer.