ABCB1 and prostate carcinoma: In other hormone-dependent neoplasms such as prostate cancer, Chen and colleagues[32] found that PXR activation by the selective potent agonist SR12813 enhanced resistance to chemotherapeutic drugs taxol and vinblastine via PXR-mediated upregulation of CYP3A4 and MDR1 in human prostate cancer PC3 cells.