CYP2E1 and risk of chemically mediated cancers.

IMPORTANCE OF THE FIELD: Among various human CYPs, CYP2E1 is of particular interest because of its involvement in the metabolic activation of many low molecular mass procarcinogens. CYP2E1 induction, which may be a consequence of genetic polymorphism or/and gene induction by xenobiotics, is the first step leading to the development of certain chemically-mediated cancers. The aim of this review is to outline the current knowledge on chemically-induced cancers through activation by CYP2E1, with emphasis on the association between polymorphisms of the CYP2E1 gene and incidence of different neoplasias. AREAS COVERED IN THIS REVIEW: Literature searches of MEDLINE (1966 to July 2009) for English articles in CYP2E1-induced carcinogenesis were conducted. WHAT THE READER WILL GAIN: CYP2E1 genetic polymorphisms leading to enhanced CYP2E1 gene transcription have been associated with increased risk of development of malignant tumours, through increased biotransformation of procarcinogens. Likewise, long-term intake of CYP2E1 inducers, such as ethanol, isoniazid, various solvents and chemicals, also increase the probability of developing malignancy, especially for carriers of certain CYP2E1 alleles. TAKE HOME MESSAGE: Genetic screening for CYP2E1 'carcinogenic' polymorphisms and CYP2E1 phenotype determination of susceptible subjects, as well as the development of effective CYP2E1 inhibitors, could be a future perspective towards prevention of CYP2E1-mediated cancers.