AGT and cancer: In this review, we will discuss the adaptive response mediated by MPT alkyltransferase activity (Section 2), the repair mechanism in the AGT family of proteins (Section 3), the distribution of the different classes of alkyltransferases in nature (Section 4), interactions of these proteins with other protein systems and their functional implications (Section 5), and the inhibition and augmentation of AGT activity in cancer chemotherapy (Section 6).