转化生长因子-β1受体拮抗剂LY2109761抑制胃癌侵袭转移的机制

Mechanism of transforming growth factor--β1 receptor antagonist LY2109761 inhibiting gastric cancer invasion and metastasis

目的探讨转化生长因子-β1（TGF-β1）受体拮抗剂LY2109761抑制胃癌细胞侵袭转移的机制。方法利用逆转录一聚合酶链反应（RT—PCR）和Westernblot检测TGF-β1及其受体拮抗剂LY2109761作用于胃癌细胞SGC7901后基质金属蛋白酶（MMP）-2、MMP-9、Smad2、血管内皮生长因子（VEGF）等与肿瘤细胞浸润、转移相关基因mRNA及蛋白的表达水平。流式细胞术检测细胞的凋亡率，Transwell迁移侵袭实验检测TGF-β1对细胞迁移及侵袭能力的影响。结果RT—PCR检测结果显示TGF一131作用于胃癌细胞时其MMP-2、MMP-9、Smad2、VEGF表达水平分别为0．83±0．10、0．74±0．11、0．60±0．08、0．79±0．12，而经LY2109761预处理后分别降为0．45±0．07、0．54±0．14、0．32±0．05、0．51±0．09；Westernblot结果显示胃癌细胞经LY2109761预处理后MMP-2、MMP-9、Smad2、VEGF的蛋白表达水平均出现下降趋势；流式细胞术显示经LY2109761预处理后胃癌细胞凋亡率从17．23％下降到5．38％（P〈0．05）；Transwell迁移及侵袭实验显示胃癌细胞经LY2109761预处理后其迁移及侵袭能力明显减弱（P〈0．05）。结论LY2109761可能是抑制了胃癌细胞的Smad信号通路、TGF-β1诱导的VEGF表达和多种MMPs的活性，从而抑制肿瘤细胞的侵袭及转移能力，具有抗肿瘤作用。

Objective To investigate ihe mechanism of transforming growth factor （TGF） -β1 re- ceptor antagonist LY2109761 inhibiting invasion and metastasis of gastric cancer cells. Methods Human gastric SGC7901 carcinoma ceils were treated with TGF-β1 and LY2109761, and the mRNA and protein expression levels of matrix metalloproteinase （MMP） -2, MMP-9, Smad2, vascular endothelial growth fac- tor （VEGF） which were related with invasion and metastasis of tumor cells were analyzed by using reverse transcriptase-polymerase chain reaction （RT-PCR） and Western blotting. The apoptosis rate was detected by using flow cytometry. Transwell migration and invasion assays were used to detect the migration and in- vasion abilities of tumor cells before and after the experiment. Results RT-PCR results showed that the ex- pression levels of MMP-2, MMP-9, Smad2 and VEGF were 0. 83 ±0. 10, 0. 74 _±0. 11, 0. 60 ±0. 08 and 0. 79 ±0. 12 respectively in gastric cancer ceils treated by TGF-151, but reduced to 0. 45 ±0. 07, 0. 54± O. 14, O. 32 ±0. 05 and O. 51 ±0. 09 in gastric cancer cells pretreated by LY2109761. Western blotting re- vealed that the protein expression levels of MMP-2, MMP-9, Smad2 and VEGF were decreased significantly in gastric cancer cells which were pretreated by LY2109761. The apoptosis rate was decreased from 17. 23% to 5.38% in gastric cancer cells pretreated by LY2109761 （P 〈0. 05）. The migration and inva- sion abilities of gastric cancer cells pretreated by LY2109761 were decreased significantly （P 〈 0. 05 ）. Conclusion LY2109761 may inhibit the Smad signaling pathway of gastric cancer ceils, TGF-β1induced VEGF expression and a variety of MMPs activity, thereby inhibiting tumor cell invasion and metastasis with the anti-tumor effect.