第10号染色体缺失的磷酸酶与张力蛋白的同源基因通过调控乳腺癌扩增性抗原1和磷酸肌醇3激酶/蛋白激酶B信号通路抑制胆管癌细胞QBC939的增殖能力

Phosphatase and tensin homolog deleted on chromosome 10 inhibits cholangiocarcinoma cell QBC939 proliferation through regulating amplified in breast cancer 1 and phosphatidylinositol 3 kinase/protein kinase B signaling pathway

目的探讨第10号染色体缺失的磷酸酶与张力蛋白的同源基因（PTEN）对人胆管癌细胞QBC939增殖能力的抑制作用及其机制。方法利用4 μg PTEN质粒或小干扰RNA（siRNA）转染人胆管癌细胞株QBC939，转染72 h后，采用噻唑蓝（MTT）实验和Western blot检测上调或下调PTEN表达对QBC939细胞增殖能力、乳腺癌扩增性抗原1（AIB1）和磷酸肌醇3激酶（PI3K）/蛋白激酶B（Akt）信号通路中重要的分子标志物表达的影响。结果人胆管癌细胞株QBC939经PTEN质粒转染72 h后，其吸光度（A）值（0.216±0.013）较对照组（0.243±0.002）降低（P＝0.026），表明增殖能力减弱，同时AIB1蛋白和PI3K/Akt信号通路中的磷酸化Akt（p-Akt）蛋白表达也明显减少。用siRNA下调PTEN表达，其A值（0.403±0.011）较对照组（0.490±0.033）降低（P＝0.013），表明增殖能力减弱，同时上调AIB1蛋白和p-Akt蛋白表达。

ObjectiveTo investigate the effects of phosphatase and tensin homolog deleted on chromosome 10 （PTEN） on proliferation of cholangiocarcinoma cell QBC939 and the mechanisms by which PTEN regulates QBC939 cell proliferation. MethodsQBC939 cells were transfected with 4 μg PTEN vector or small interfering RNA （siRNA） for 72 h. Then methyl thiazol tetrazolium （MTT） assays was used to detect the ability of cells proliferation and Western blotting was performed to detect the protein levels of amplified in breast cancer 1 （AIB1） and significant molecular marker of phosphaidylinositol 3 kinase （PI3K）/protein kinase B （Akt） signal pathway after PTEN was overexperssed or downregulated by siRNA in QBC939 cells. ResultsAfter 72 h transfection, the absorbance （A） value of PTEN-overexpressed group （0.216±0.013） was lower than that of the control group （0.243±0.002, P=0.026）, which indicated that the proliferation of QBC939 cells was inhibited, meanwhile the expression of AIB1 and phosphorylated Akt （p-Akt） which was phosphorylated in PI3K/Akt signal pathway was significantly decreased. Down-regulation of PTEN through siRNA resulted in that its A value （0.403±0.011） was lower than that of the control group （0.490±0.033, P=0.013）, which promoted the proliferation of QBC939 cells, and that up-regulated the expression of AIB1 and p-Akt. ConclusionThese results suggest that PTEN inhibited cholangiocarcinoma cell proliferation through regulating AIB1 and PI3K/Akt signaling pathway.