ABCB4 and prostate cancer: Kharaziha et al. conducted proteomic analysis on EVs derived from prostate cancer cells sensitive vs. resistant to docetaxel, identifying multidrug resistance protein 1 (MDR-1), MDR-3, endophilin-A2, and poly(A) binding protein 4 as proteins enriched in the latter as well as present in EVs from the serum of castration-resistant prostate cancer patients, suggesting that EVs may be used as biomarker candidates for predicting therapeutic response or resistance[143].