Variability and regulation of O6-alkylguanine-DNA alkyltransferase.

O(6)-Alkylguanine-DNA alkyltransferase (ATase) confers resistance to many of the biological effects of certain classes of alkylating agents by repairing the DNA lesions responsible. The role of ATase in the mutagenic and toxic effects of the carcinogenic and antitumour alkylating agents are of interest in relation to the prevention and treatment of cancer in man. In this commentary we specifically focus on the variation in ATase levels and our current understanding of the factors involved in the regulation of ATase expression.