A significant reduction in occludin mRNA levels was observed in CAHPV-10 (−19.08 fold, p = 0.001), DU145 (−3.2 fold, p = 0.003) and PC-3 (−4.3 fold, p = 0.003) prostate cancer cells compared to normal prostate epithelial cells (PNT2). This evidence concerns the gene OCLN and prostate cancer.