Microsomal epoxide hydrolase gene polymorphisms and susceptibility to prostate cancer: A systematic review.

Microsomal epoxide hydrolase (mEH) is a crucial biotransformation enzyme that has capability to metabolize a large number of structurally divergent, highly reactive epoxides, and numerous environmentally exposed carcinogens. It catalyzes the conversion of xenobiotic epoxide compounds into more polar diol metabolites and may play important part of the enzymatic defense against adverse effects of foreign compounds. Most commonly, two functional polymorphisms affecting mEH enzyme activity have been identified: One in exon 3 and other in exon 4 of the mEH gene, which results in His113Tyr and Arg139His amino acid substitutions, respectively. Recent reports have shown that polymorphisms in mEH gene loci may an important risk factor for susceptibility of prostate cancers (PCs), worldwide, but inconsistent finding were also be illustrated. To the best of our knowledge, globally, there is no any systematic review has been published related to mEH gene polymorphisms and PC risk. Thus, in the current review, we have discussed the association between mEH gene polymorphisms, gene–environmental interaction, and PC risk.