Rifamycin in reversing multidrug-resistance in human lung adenocarcinoma cell line A_(549)/ADM:An experimental study

Objective:To investigate the mechanisms of multidrug resistance in human lung adenocarcinoma cell line A549/ADM and the reversion of multidrug resistance with rifamycin.Methods:The expressions of P-glycoprotein(P-gp) and multidrug resistance-associated protein(MRP) were detected with flow cytometry.The resistance to chemotherapeutic drugs and the reversion with rifamycin was evaluated with MTT assay.The accumulation of ADM in A549/ADM cells was evaluated with flow cytometry.Results:The expression of P-gp and MRP enhanced significantly(74.8% and 61.2%) compared with A549 cells;with rifamycin(8 μg/ml)added,the sensitivity of A549/ADM cells to ADM raised by 2.51 times and accumulation of ADM in A549/ADM cells was significantly increased.The sensitivity to VCR,DDP and VP-16 increased by 7.38,1.29 and 2.86 times respecitively.Conclusions:A549/ADM cells are resistant to many commonly used anti-cancer chemotherapeutic drugs and the resistance might be related to P-gp and MRP overexpression.Rifamycin could reverse the MDR of lung adenocarcinoma cell lines A549/ADM.