p38 MAPK信号通路在伊立替康诱导结肠癌SW620细胞凋亡中的作用分析

Role of p38 MAPK signaling pathway in apoptosis of colon cancer cell line SW620 induced by irinotecan

目的探讨p38 MAPK信号通路在伊立替康诱导结肠癌细胞SW620凋亡过程中的变化及机制。方法利用MTT实验和流式细胞术检测不同浓度(20μmol/L、40μmol/L、80μmol/L)伊立替康对SW620细胞的增殖抑制和凋亡作用,通过酶联免疫吸附试验(ELISA)测定该药对细胞p38活性的影响。利用p38抑制剂以及siRNA转染技术,分析p38 MAPK信号通路在伊立替康诱导SW620细胞凋亡过程中的变化。结果伊立替康抑制SW620细胞的生长和增殖的作用均呈时间和剂量依赖性。SW620细胞增殖率随着伊立替康浓度的升高显著下降,不同浓度处理组的增殖率随时间显著降低(P均<0.05)。抑制率方面,无论是早期还是晚期,20μmol/L伊立替康组诱导SW620细胞凋亡率与对照组相比均无统计学差异(P>0.05),但40μmol/L、80μmol/L组凋亡率均显著增加(P均<0.05),且后两组抑制率在晚期均显著降低(P均<0.05)。80μmol/L伊立替康处理SW620细胞后的p38激活相对缓慢,12 h时p38活性急剧升高,达到峰值,之后缓慢减弱。80μmol/L伊立替康诱导SW620细胞凋亡率为25.19%±1.25%,与其相比,p38活性抑制后的SB203580组及p38 siRNA组细胞凋亡率显著减少,分别为13.37%±0.96%和8.07%±1.32%(P<0.05)。结论p38 MAPK信号通路参与伊立替康诱导SW620细胞凋亡,其作用与p38活性相关。

Objective To investigate the changes and mechanism of p38MAPK signaling pathway in the apoptosis of colon cancer cell line SW620 induced by irinotecan.Methods MTT assay and flow cytometry were used to detect the proliferation,inhibition and apoptosis of SW620 cells with different concentrations(20μmol/L,40μmol/L,80μmol/L)of irinotecan.The effect of irinotecan on cell p38 activity was determined by enzyme-linked immunosorbent assay(ELISA).The changes of p38 MAPK signaling pathway in the apoptosis of SW620 cells induced by irinotecan were analyzed by using p38 inhibitor and siRNA transfection technology.Results Irinotecan inhibited the growth and proliferation of SW620 cells in a time-and dose-dependent manner.The proliferation rate of SW620 cells decreased over time(P<0.05)and with concentration increasing(P<0.05).The total apoptotic rate of SW620 cells induced by 20μmol/L irinotecan group had no significant difference with that of the control group(P>0.05),but was significantly less than that of the 40μmol/L group and the 80μmol/L group(P<0.05,respectively).The activation of p38 in SW620 cells treated with 80μmol/L irinotecan was relatively slow,it peaked at 12 h,and then slowly weakened.The apoptosis rate of SW620 cells induced by 80μmol/L of irinotecan was significantly higher than that in SB203580 group and p38 siRNA group(P<0.05,respectively).Conclusion The p38 MAPK signaling pathway is involved in the apoptosis of SW620 cells induced by irinotecan,and its effect is related to p38 activity.