ABCB1 and prostate cancer: Mechanistically, it is known that the E2F-associated phosphoprotein stimulates the MDR1/P-gp promoter, leading to the upregulation of MDR1/P-gp in a p21-dependent manner.30 Interestingly, MDR1/P-gp has also been shown to transfer resistance to docetaxel via EVs in breast and prostate cancer cells.25, 31