STC2 基因在乳腺癌中的表达及抑制其表达对癌细胞生物学特性的影响研究

目的:探讨斯钙素鄄2(STC2)基因在乳腺癌中的表达及抑制其表达对癌细胞增殖、周期及凋亡的影响。方法:RT鄄PCR 及Western blot 分别检测乳腺癌组织中STC2 基因的mRNA 及蛋白表达,并分析其与病理特征的关系;将STC2-siRNA转染人乳腺癌MCF-7 细胞,另设空白对照组(Control)和阴性对照组(NC-siRNA),转染48 h 后,Western blot 检测各组细胞中STC2、ki67、细胞周期素(cyclin D1)、活化的含半胱氨酸的天冬氨酸蛋白水解酶3(Cleaved caspase3)、Notch1、Hes1 蛋白表达;CCK8 检测细胞增殖;流式细胞仪检测细胞周期及凋亡。结果:STC2 基因在乳腺癌中的mRNA 及蛋白表达均显著高于癌旁组织(P<0.05);STC2 基因表达与乳腺癌患者年龄、组织学分级及是否发生转移无关(P>0郾05),与病理分期、肿瘤大小相关(P<0.05);NC-siRNA 组STC2 的蛋白表达与Control 组差异无统计学意义(P>0.05),STC2鄄siRNA 组STC2 的蛋白表达显著低于Control 组(P<0.05);STC2鄄siRNA 组细胞存活率、S 期和G2/ M 细胞及ki67、cyclin D1、Notch1、Hes1 蛋白表达显著低于Control组,细胞凋亡率、G0/ G1 期细胞及Cleaved caspase3 蛋白表达显著高于Control 组(P<0.05)。结论:STC2 基因在乳腺癌中高表达,其表达与病理分期和肿瘤大小相关,抑制其表达可降低癌细胞的增殖,阻滞细胞于G1 期,并诱导细胞凋亡,其机制与下调ki67、cyclin D1 和上调Cleaved caspase3 表达及下调Notch1 信号通路有关。

Expression of STC2 gene in breast cancer and influence of its expression on#br# biological characteristics of cancer cells

Objective:To investigate the expression of STC2 gene in breast cancer and the influence of its expression on theproliferation,cycle and apoptosis of cancer cells.Methods:RT-PCR and Western blot were used to detect mRNA and protein expressionof STC2 gene in breast cancer,and to analyze the relationship with pathological features;STC2-siRNA transfected human breast cancercell line MCF-7,a blank control group(control)and negative control group(NC-siRNA)were set,expression of STC2,ki67,cyclin D1,Cleaved caspase3,Notch1,Hes1 protein after transfected for 48 h were detected Western blot;cell proliferation was detected by CCK8assay;cell cycle and apoptosis were detected by flow cytometry.Results:The mRNA and protein expression of STC2 gene in breastcancer were significantly higher than adjacent tissues(P<0.05);the expression of STC2 gene was not correlated with age,histologicalgrade and metastasis of breast cancer patients(P >0.05),was correlated with pathological stage and tumor size(P <0.05);STC2expression had no significant difference between NC-siRNA group and control group(P>0.05),expression of STC2 protein in STC2-siRNA group was significantly lower than control group(P<0.05);the cell survival rate,S cell and G2/ M cell and the expression ofki67,cyclin D1,Notch1 and Hes1 protein in STC2-siRNA group were significantly lower than control group,the apoptosis rate,G0/ G1cells and Cleaved caspase3 protein expression was significantly higher than Control group(P<0.05).Conclusion:The expression ofSTC2 gene in breast cancer was higher,the expression was correlated with pathological stage and tumor size,the inhibition of itsexpression can reduce the proliferation of cancer cells,block cells in G1 stage,and induce cell apoptosis,the mechanism is related todown regulation of ki67,cyclin D1 expression and up regulation of Cleaved caspase3 expression and down regulation of Notch1 signalingpathway.