In this review proteins associated with tight junctions (TJs) is described with an emphasis on prostate cancer. Overall tight junctional proteins do not seem to play a decisive role in prostate carcinoma pathogenesis. Of TJ proteins, expression of some claudins show an association with clinical behaviour of the tumors. Claudin 1 expression appears to be related to a better prognosis partly due to its involvement in EMT abrogation. Claudin 3 and 4 are highly expressed in prostate cancer and their expression is associated with aggressive behaviour. Inhibition of claudin 8 promotes prostate carcinoma invasion and spread but studies are few. CPE has been known to bind to especially claudins 3 and 4 and cause cell lysis. Several experiments with modified CPE have been made in prostate cancer cell lines. Regardless of this effective CPE based human treatment for prostate cancer have not yet been developed.