HPGDS and cancer: Changed expression of enzymes elaborated in phase II of drug metabolism, comprising glutathione-S-transferases (GSTs), gamma-glutamyl transferases (GTs), thiopurine methyltransferases (TPMTs), uridine diphospho-glucuronosyltransferases (UGTs), and dihydropyrimidine dehydrogenases (DPDs) in cancer cells may improve their MDR.