DNA direct reversal repair and alkylating agent drug resistance.

DNA direct reversal repair (DRR) is unique in that no DNA synthesis is required to correct the error and therefore repair via such mechanisms are error-free. In humans, DRR is carried out by two different pathways: the O6-methylguanine-DNA methyltransferase (MGMT) and the alkylated DNA repair protein B (AlkB) homologs. The use of alkylating agents is the standard of care for many cancers. However, the use of those drugs is usually halted when resistance develops. This review will examine repair of alkylating agent damage mediated by DRR, resistance mechanisms and potential ways to overcome such resistance.