低频超声联合紫杉醇对人乳腺癌MCF-7细胞增殖和凋亡的影响

Effect of low-frequency ultrasound combined with paclitaxel on proliferation and apoptosis in breast cancer MCF-7 cell line

目的研究低频超声和紫杉醇联合应用对乳腺癌MCF-7细胞增殖和凋亡的影响以及其可能机制。方法培养乳腺癌MCF-7细胞,随机分为4组:对照组、低频超声组、紫杉醇组和低频超声+紫杉醇组。低2频超声组为超声840k Hz,0.75W/cm×3min辐照;紫杉醇组为药物浓度为10nmol/L培养24h;联合组叠加处理因素。应用CCK-8检测细胞增殖,应用流式细胞仪和凋亡试剂盒检测各组细胞凋亡,应用流式细胞仪和ROS试剂盒检测各组细胞ROS水平,应用Western Blot实验检测凋亡相关蛋白表达。结果单独应用低频超声或紫杉醇均能抑制MCF-7细胞增殖,诱导细胞凋亡,升高细胞内活性氧水平,增加凋亡相关蛋白(cleaved caspase-3、cleaved caspase-2、Bax)的表达水平,降低Bcl-2的表达水平。与单独应用组相比,低频超声和紫杉醇联合,显著增强了上述作用。结论低频超声和紫杉醇联合作用,极大增强了抑制MCF-7细胞增殖,诱发其凋亡的作用,其作用可能和线粒体凋亡途径相关。

Objective To study the effect and possible mechanism of low-frequency ultrasound combined with paclitaxel on breast cancer MCF-7 cells proliferation and apoptosis. Methods The breast cancer MCF-7 cells were cultured divided into 4 groups randomly： control group, low-frequency ultrasound group（840k Hz,0.75W/ cm2×3min ultrasound treated）, paclitaxel group（10nmol/L for 24h） and low-frequency ultrasound＋paclitaxel group. CCK-8 assay was used to detect cells proliferation, flow cytometry and apoptosis kit to detect apoptosis, flow cytometry and ROS kit to detect the levels of ROS, Western Blot to examine apoptosis-related proteins. Results Low-frequency ultrasound or paclitaxel inhibited MCF-7 cells proliferation, induced apoptosis, increased intracellular ROS levels, increased the expression of apoptosis-related proteins（cleaved caspase-3, cleaved caspase-2 and Bax）, downregulated Bcl-2 expression level. The combination of low-frequency ultrasound and paclitaxel enhanced these effects synergistically in MCF-7 cells, compared with low-frequency ultrasound or paclitaxel alone. Conclusion The synergistic effect of low-frequency ultrasound and paclitaxel combination enhanced the abilities of inhibiting proliferation and inducing apoptosis in MCF-7 cells, which might be related to mitochondrial apoptosis pathway.