葫芦素B对人肺鳞癌NCI-H520细胞增殖及凋亡的影响

Effects of cucurbitacin B on proliferation and apoptosis of human squamous cell lung carcinoma NCI-H520 cells

目的探讨葫芦素B对人肺鳞癌NCI-H520细胞增殖及凋亡的影响。方法体外培养NCI-H520细胞,MTT法观察葫芦素B对细胞增殖的影响;倒置相差显微镜、Hoechst 33258荧光染色法观察葫芦素B作用前后细胞形态的变化;采用流式细胞术检测细胞凋亡率;采用Westen blot方法检测葫芦素B对T-STAT3、p-STAT3表达的影响。结果葫芦素B对NCI-H520细胞的增殖有抑制作用,且呈剂量、时间依赖性;葫芦素B处理组细胞形态发生显著性改变,细胞皱缩、变圆,可见胞核染色质浓缩、核固缩、核碎裂等典型的凋亡改变;流式细胞仪检测结果显示NCI-H520细胞凋亡率随葫芦素B作用浓度增加而增加,呈剂量依赖性;葫芦素B呈剂量依赖性抑制p-STAT3蛋白的表达,对T-STAT3的表达无影响。结论葫芦素B可能通过抑制STAT3信号通路的活化抑制NCI-H520细胞的增殖并诱导细胞凋亡。

Objective To study the influence of Cucurbitacin B on the proliferation and apoptosis of human squamous cell lung carcinoma NCI-H520 cells.Method Human squamous cell lung carcinoma NCI-H520 cells were cultured in vitro.The growth inhibitory effect of Cucurbitacin B on NCI-H520 cells was detected by MTT assay.The morphology of the cells was evaluated using inverted phase contrast microscope and Hoechst 33258 staining.Apoptosis rate was determined by flow cytometry analysis.The expression of total STAT3（TSTAT3） and phosphorylated STAT3（p-STAT3） was determined by Western blot after Cucurbitacin B treatment.Result The growth of NCI-H520 cells was inhibited by Cucurbitacin B in a dose-and time-dependent manner.Marked morphological changes such as cell volume shrinking,condensation of chromatin,karyopyknosis and nuclear fragmentation were observed after treated by Cucurbitacin B.Flow cytometry analysis showed that Cucurbitacin B could induce NCI-H520 cells apoptosis in a dose-dependent manner.Cucurbitacin B suppressed p-STAT3 in a dose-dependent manner,while had no effect on the level of T-STAT3.Conclusion Cucurbitacin B could inhibit proliferation and induce apoptosis via STAT3 pathway inhibition in NCI-H520 cell line.