紫杉醇脂质体与培美曲塞在乳腺癌细胞SK-BR-3中放疗增敏作用的比较及其机制

目的:比较紫杉醇脂质体（力扑素）与培美曲塞在乳腺癌细胞SK-BR-3中的放疗增敏作用，探索两者放疗增敏作用的机制。方法:分组设置为细胞对照组、放疗组、力扑素+放疗组、培美曲塞+放疗组。MTT法检测不同处理组细胞生长抑制率，流式细胞仪检测不同处理组细胞周期及凋亡率，Western blot检测不同处理组凋亡相关蛋白Caspase-3、Bcl-2及Bax的表达。结果:MTT结果显示，力扑素+放疗能够发挥比培美曲塞+放疗更明显的细胞生长抑制作用，两者相比有统计学差异（P＜0.05）；流式检测结果显示，力扑素+放疗能够引起更明显的细胞凋亡，与培美曲塞+放疗相比有统计学差异（P＜0.05），同样力扑素+放疗在细胞周期中能够诱导产生更明显的亚G1峰，与培美曲塞+放疗相比有统计学差异（P＜0.05）；Western blot结果显示，促凋亡蛋白Caspase-3和Bax的表达在不同处理组中均升高，但力扑素+放疗组升高更显著，与培美曲塞+放疗相比有统计学差异（P＜0.05），而抗凋亡蛋白Bcl-2的表达在不同处理组中均降低，但力扑素+放疗比培美曲塞+放疗降低更明显,有统计学差异（P＜0.05）。结论:力扑素比培美曲塞具有更强的放疗增敏作用，并且可能是通过调控凋亡蛋白的表达来发挥其放疗增敏作用的。

Effect of radiosensitization between Paclitaxel liposome and Pemetrexed and the mecha-nism

Objective:To compare the effect of radiosensitization between Paclitaxel liposome and Pemetrexed and explore their mechanism in breast cancer cell line SK-BR-3.Methods:MTT assay was used to test the inhibitory effect of Paclitaxel liposome combined with radiotherapy and Pemetrexed combined with radiotherapy in breast cancer cell line SK-BR-3.Flow cytometry instrument to detect the cell cycle and apoptosis.Western blot to detect apoptosis related proteins Bcl-2,Bax and casepase-3.Results:The cell growth inhibition of Paclitaxel liposome combined with radiotherapy showed more significant than Pemetrexed combined with radiotherapy and single radiotherapy,the difference was statistically significant(P＜0.05).Apoptosis after the Paclitaxel liposome combination group showed more significant than radiotherapy group and Pemetrexed combined group,the difference was statistically significant (P＜0.05).Combination groups and radiotherapy group caused the appearance of sub-G1 peak,and combination groups showed more significant than radiotherapy group,the difference was statistically significant(P＜0.05).Conclusion:The effect of radiosensitization is stronger than Pemetrexed and through regulating the expression of apoptosis proteins Paclitaxel liposome achieved the effect of radiosensitization.