γ分泌酶抑制剂阻断Notch信号通路对人卵巢癌SKOV3细胞增殖和凋亡的影响

Notch Signaling Pathway Blocked byγ-secretase Inhibitor and Its Effect on the Growth and Apoptosis of SKOV3 Cells

目的观察γ分泌酶抑制剂(DAPT)对人宫颈癌SKOV3细胞增殖和凋亡的影响,并探讨其作用机制。方法不同浓度DAPT对SKOV3细胞作用后,采用CCK-8法检测对SKOV3细胞的增殖抑制作用,吖啶橙/溴化乙锭(AO/EB)荧光双染色法及流式细胞术检测细胞凋亡,RT-PCR、Western blot检测SKOV3细胞Notch1mRNA和蛋白表达水平的变化。结果与空白对照组相比,5μmol/L、10μmol/L、20μmol/L浓度的DAPT对SKOV3细胞均有一定的增殖抑制作用(P<0.05),且其抑制作用呈剂量依耐性增加(P<0.05),24h抑制率分别为19.87%、28.38%、46.67%。与空白对照组相比,不同浓度的DAPT作用SKOV3细胞24h后凋亡率增加(P<0.05),且随DAPT浓度增加,凋亡细胞逐渐从早期凋亡过渡至晚期凋亡;Notch1mRNA和蛋白表达抑制,其抑制率分别为(10.23%、20.50%、38.83%)和(12.89%、27.47%、49.84%)。结论γ分泌酶抑制剂DAPT可阻断Notch信号通路,能抑制卵巢癌SKOV3细胞的增殖,促进细胞凋亡,其作用机制可能与下调Notch1表达有关。

Objective To determine the effect and mechanism ofγ-secretase inhibitor DAPT on the growth and apoptosis of human ovarian carcinoma SKOV3cells.Methods The effect ofγ-secretase inhibitor DAPT was tested in vitro using SKOV3cells.Its inhibition effect on cell proliferation was determined by CCK-8assay.The cell apoptosis was detected by AO/EB double staining and flow cytometry.The expression of Notch1mRNA and protein was detected by RT-PCR and Western blot.Results Compared with controls,5μmol/L,10μmol/L and 20μmol/L of DAPT showed an effect of cell growth inhibition in a dose-dependent manner,with 19.87%,28.38%,and 46.67% of 24hinhibitory rates,respectively.Dose-dependent effect of DAPT on cell apoptosis was also evident,with（5.80±0.98）%,（12.96±4.99）%,（30.88±7.63）%,and（42.98±1.46）%apoptosis rates for the control,5μmol/L,10μmol/L and 20μmol/L DAPT groups,respectively.RT-PCR analysis demonstrated that the expression of Notch1 mRNA decreased significantly in the DAPT groups,with an inhibition rate of10.23%,20.50%,and 38.83%for the three DAPT groups,respectively.Western blot results demonstrated that the expression of Notch1protein decreased significantly,with an inhibition rate of 12.89%,27.47%,and 49.84%for the three DAPT groups,respectively.Conclusion γ-secretase inhibitor DAPT can block Notch signaling pathway,inhibit proliferation,and induce apoptosis of SKOV3cells through down-regulation of the expression of Notch1.