肿瘤坏死因子超家族成员9在肝癌组织的表达及其对肝癌细胞增殖和侵袭的影响

The expression of tumor necrosis factor superfamily member 9 in hepatocellular carcinoma and the effects of tumor necrosis factor superfamily member 9 overexpression on proliferation and invasion of hepatocellular carcinoma cells

目的检测肿瘤坏死因子超家族成员9（TNFSF9）在人肝癌组织的表达，探讨TNFSF9过表达对肝癌细胞增殖和侵袭的作用及其分子机制。方法免疫组织化学法和实时定量聚合酶链反应（Real-time PCR）检测TNFSF9在50例人肝癌及癌旁组织的表达。利用慢病毒载体构建稳定过表达TNFSF9的肝癌HepG2细胞株，Real-time PCR和Western blot检测TNFSF9、增殖细胞核抗原（PCNA）和基质金属蛋白酶-9（MMP-9）的表达水平。噻唑蓝（MTT）法和Transwell实验检测TNFSF9过表达对肝癌细胞增殖和侵袭的影响。结果与癌旁组织（0.30±0.03）比较，TNFSF9在肝癌组织的mRNA表达量较低（0.18±0.02），其蛋白在肝癌组织的阳性表达率较低（26.0%比54.0%，P＝0.004）。体外实验结果显示，TNFSF9过表达减少PCNA和MMP-9蛋白的表达，并抑制肝癌细胞增殖活性；与对照组穿过小室的细胞数[（105.5±11.2）个]比较，TNFSF9组侵袭的肝癌细胞数（[52.8±7.4）个]明显减少（P＝0.000）。结论TNFSF9在人肝癌组织低表达，其过表达抑制肝癌细胞的增殖和侵袭潜能。

Objective To investigate the expression of tumor necrosis factor superfamily member 9 （TNFSF9） in human hepatocellular carcinoma （HCC） and adjacent normal tissues, and explore the effects and molecular mechanism of TNFSF9 overexpression on proliferation and invasion of HCC cells.MethodsThe expression of TNFSF9 in 50 cases of HCC and corresponding normal tissues was detected by immunohistochemistry and real-time quantitative polymerase chain reaction （Real-time PCR） assays. HCC HepG2 cells stably transfected with lentivirus-mediated TNFSF9 overexpression were built up and the expression levels of TNFSF9, proliferating cell nuclear antigen （PCNA） and metalloproteinase-9 （MMP-9） were examined by Real-time PCR and Western blotting assays. The proliferative activity and invasive capability of HCC cells were evaluated by methyl thiazol tetrazolium （MTT） and Transwell assays.ResultsThe expression of TNFSF9 was decreased in 26.0% HCC tissues, and its mRNA expression level （0.18±0.02） in HCC was significantly decreased as compared with that （0.30±0.03） in adjacent non-cancer tissues. TNFSF9 overexpression downregulated the expression of PCNA and MMP-9, and inhibited the proliferative and invasive capability of HCC cells.ConclusionTNFSF9 is lowly expressed in HCC tissues, and overexpression of TNFSF9 inhibits proliferation and invasion of HCC cells.