Overexpression Of AQP9 Can Enhance Cisplatin Induced Apoptosis Of SMMC-7721 Cell Line

ObjectiveTo investigate the effect of aquaglyceroporin9(AQP9)on apoptosis of human hepatoma carcinoma SMMC-7721 cells induced by cisplatin and its possible mechanism.MethodsSMMC-7721 cells were transfected with recombinant lentivirus LV-AQP9 and LV-GFP separately.The infection efficiency of recombinant lentivirus LV-AQP9 was observed under the confocal microscope The expression of AQP9 was detected by real-time PCR and western blot.The cell inhibition rates of liver cancer SMMC-7721 cells were detected after cells were incubated with different concentrations of cisplatin for 24,36,48 h.Then the best concentration and incubation time of cisplatin were selected.There were four groups: GFP group?AQP9 group?GFP combined with DDP group?AQP9 combined with DDP group.The flow cytometry was applied to detect apoptosis.The expression of related proteins were detected by western blot.ResultsThe infection efficiency of recombinant lentivirus LV-AQP9 in SMMC-7721 cells was above 90% under the fluorescence microscope.The over-expression of AQP9 was successfully detected in SMMC-7721 cells(P?0.01).The half inhibition concentration(IC50)of SMMC-7721 cells treated with cisplatin for 24 h was 5 ug / mL.There were significant difference among the four groups in cells apoptosis rate(P < 0.05).AQP9 expression significantly promoted apoptosis(FAQP9 = 71.391.780,P = 0.000);DDP induced more liver cancer cell apoptosis(FCDDP = 361.682,P = 0.000;AQP9 can significantly enhance liver cancer cell apoptosis induced by cisplatin.Both have synergy(FAQP9×CDDP=26.681,P=0.001).All above results were analyzed by multiple factor variance analysis.The expression of GRP78 and cleaved Caspase12 were significantly higher in AQP9 combined DDP group compared with other three groups(P < 0.01).There was no significant difference between GFP group and AQP9 group.ConclusionOver-expression of AQP9 can enhance liver cancer SMMC-7721 cell apoptosis which induced by cisplatin and increased its sensitivity of chemotherapy.AQP9 over-expression may induce apoptosis through the activated endoplasmic reticulum stress signaling pathway,then promote apoptosis by cooperated with DDP.