胰岛素对子宫内膜癌细胞增殖和凋亡的影响

目的 探讨胰岛素对子宫内膜癌细胞系Ishikawa3-H-12细胞增殖、凋亡和细胞周期的影响。方法 应用免疫细胞化学方法和RT-PCR技术检测Ishikawa3-H-12细胞胰岛素受体（INSR）蛋白和mRNA的表达。以不同浓度胰岛素作用Ishikawa3-H-12细胞不同时间,采用四甲基偶氮唑蓝比色法、流式细胞仪检测细胞增殖、凋亡和细胞周期。结果 （1）Ishikawa3-H-12细胞INSR蛋白呈棕黄色阳性表达,并可见INSR基因的表达。（2）胰岛素以浓度和时间依赖的方式促进子宫内膜癌细胞增殖,1×10^-4mol／L胰岛素作用48h时促增殖作用最显著,增殖率为（340．2±15．9）％,与对照细胞（以胰岛素浓度为0作为对照,为100％）比较,差异有统计学意义（P〈0．05）。（3）胰岛素以浓度和时间依赖的方式使Ishikawa3-H-12细胞中G0／G1期细胞比例减少,S期细胞比例增加,1×10^-4mol／L胰岛素作用72h时最显著,G0／G1期细胞比例为（27．7±2．5）％,S期细胞为（55．2±1．4）％,分别与对照细胞[分别为（67．6±1．5）％、（15．7±1．0）％]比较,差异均有统计学意义（P〈0．05）;胰岛素对G2／M期细胞无影响（P〉0．05）。（4）随着胰岛素浓度的增加,Ishikawa3-H-12细胞凋亡率逐渐下降。1×10^-4mol／L胰岛素作用最显著,作用24、48、72、96h时的细胞凋亡率分别为（1．76±0．16）％、（1．70±0．15）％、（1．56±0．20）％、（1．31±0．24）％,分别与对照细[分别为（9．81±0．61）％、（9．93±1．44）％、（9．10±0．66）％、（10．30±1．20）％]比较,差异均有统计学意义（P〈0．05）。结论 胰岛素对子宫内膜癌Ishikawa3-H-12细胞具有促进增殖、抑制凋亡的作用。

Effects of insulin on proliferation and apoptosis of endometrial carcinoma cell

OBJECTIVE: To study the expression of insulin receptor (INSR) in endometrial cell line Ishikawa3-H-12, and the effects of insulin on proliferation, cell cycle distribution and apoptosis of Ishikawa3-H-12 cells. METHODS: Immunocytochemistry and RT-PCR methods were used to investigate the expression of INSR in Ishikawa3-H-12 cells. The effects of insulin at different concentrations and different time on proliferation, apoptosis and cell cycle distribution of endometrial carcinoma cells were observed by methyl thiazolyl tetrazolium (MTT) assay and fluorescence-activated cell sorting technique. RESULTS: (1) We demonstrated the expression of INSR in Ishikawa3-H-12 cell line. (2) Incubation with insulin stimulated a dose- and time-dependent proliferation response in Ishikawa3-H-12 cells with the peak response occurring at 48 hours with 1 x 10(-4) mol/L insulin incubation [proliferative rate: (340.2 +/- 15.9)%, vs control (100%), P < 0.05]. (3) The percentage of Ishikawa3-H-12 cells at G(0)/G(1) phase decreased and percentage at S phase increased significantly with insulin treatment in a dose- and time-dependent manner with the peak response occurring at 72 hours with 1 x 10(-4) mol/L insulin incubation [G(0)/G(1) phase (27.7 +/- 2.5)%, S phase (55.2 +/- 1.4)%, vs control: (67.6 +/- 1.5)% and (15.7 +/- 1.0)%, P < 0.05], whereas that of G(2)/M phase did not show significant alteration. (4) The apoptosis rate of Ishikawa3-H-12 cells was decreased gradually with increasing concentration of insulin, while the alteration was time-independent. The peak response occurred with 1 x 10(-4) mol/L insulin incubation [apoptosis rate: (1.76 +/- 0.16)%, (1.70 +/- 0.15)%, (1.56 +/- 0.20)%, (1.31 +/- 0.24)% when incubated at 24, 48, 72 and 96 hours respectively, vs control, P < 0.05]. CONCLUSION: Insulin can promote the proliferation and inhibit the apoptosis of endometrial carcinoma cells.