Studies on the expression of claudin-3 in various type of prostate disease—prostatic adenocarcinoma (NAC), benign prostatic hyperplasia (BPH), prostatic intraepithelial neoplasia (PIN), prostate cancer, and metastatic prostatic adenocarcinoma (Mets)—reported that expression of theses claudins was upregulated in malignant tumor [66]. The gene discussed is CLDN3; the disease is prostate intraepithelial neoplasia.