GSTP1 and urinary bladder neoplasm: For example, the high content of GSTP1 in urothelium may be responsible for the detoxification of benzo[a]pyrene dihydrodiol epoxide (Simic et al. 2009), but at the same time, overexpression of GSTP1, very often observed in urinary bladder tumors, may be linked with drug resistance during chemotherapy (Harbottle et al. 2001).