|
Objective: To investigate recombinant human endostatin (rh-Endostatin) on human lung adenocarcinoma cell A549/DDP resistance reversal effect and its mechanism. Methods: In this study, human lung adenocarcinoma A549 cells and cisplatin (DDP) A549/DDP resistant cells as a research object, the DDP with rh-Endostatin to separately administered and their combination mode of administration, the role of in human lung cancer cell line A549 and resistant cell lines A549/DDP, reaction time 72 hours, observe the different modes of administration the same strain caused by the difference between the cells and drug resistance among different cell lines resistant difference. 1 using MTT assay rh-Endostatin and DDP on lung adenocarcinoma cell line A549 and resistant strains A549/DDP cell growth inhibition, determined rh-Endostatin no cytotoxicity half inhibitory concentration and the DDP rate (IC50), determine resistance index. 2 with Caspase-3 spectrophotometry rh-Endostatin monotherapy group, DDP monotherapy group, and rh-Endostatin and DDP group were acting on A549/DDP cells apoptosis rate. 3 using western blot assay rh-Endostatin monotherapy group, DDP monotherapy group, and rh-Endostatin and DDP group were acting on the cells of the resistance protein A549/DDP lung resistance protein (LRP) and glutathione -S-transferase (GST) expression. Results: 1.MTT assay showed that: the concentration of 400ug/ml role of rh-Endostatin A549/DDP 72 hours on A549 cells and no cytotoxicity. DDP on A549 cell half inhibitory concentration (IC50) was 0.79 ± 0.06ug/ml, on A549/DDP cells with IC50 of 13.3 ± 0.9ug/ml, A549/DDP to DDP resistance index was 16.8. rh-Endostatin and DDP in combination, the resistant cells with IC50 A549/DDP dropped 2.57 ± 0.04ug/ml, reversal fold (RF) 5.14, relative reversal rate (RRR%) 85.6%, prompted rh-Endostatin likely to enhance the DDP on the cytotoxicity of A549/DDP has some role reversal A549/DDP resistant cells. 2.Caspase-3 spectrophotometry results: rh-Endostatin monotherapy group measured OD value 0.034 ± 0.21, DDP monotherapy group was 1.289 ± 0.39, rh-Endostatin and DDP group was 2.693 ± 0.78, A549/DDP cell control group was 0.015 ± 0.35. Combined treatment group compared with the separate administration group P = 0.00, statistically significant. 3.western blot results showed: A549/DDP intracellular LRP, GST protein expression, rh-Endostatin and DDP group treated A549/DDP cells LRP, GST protein expression were decreased significantly. (P = 0.00, statistically significant.) Conclusion: rh-Endostatin partially reversed A549/DDP cells resistant to DDP, the reversal mechanism may A549/DDP intracellular LRP and GST protein expression was reduced, the cells wither associated with increased death.
|