目的： 探索转化生长因子-β超家族细胞因子激活素A（activin A）对胃癌细胞迁移和有氧糖酵解的影响,及其编码基因抑制素βA亚基（inhibin βA, INHBA）表达水平与胃癌患者预后的相关性。方法： 用不同浓度激活素 A处理胃癌细胞,蛋白质免疫印迹（Western blotting,Wb）检测激活素信号通路下游磷酸化Smad2/3（phosphorylated Smad2/3,pSmad2/3）水平上调情况,确定合适的激活素 A作用浓度。Transwell和划痕实验评价激活素 A对胃癌细胞迁移的影响,检测乳酸生成和葡萄糖摄取探索激活素 A对胃癌细胞有氧糖酵解的影响。癌症基因组图谱（the Cancer Genome Atlas,TCGA）数据库基因表达水平相关性分析联合Wb验证,探索激活素 A可能影响哪些上皮间质转化（epithelial mesenchymal transformation, EMT）和糖酵解相关基因。利用TCGA、基因表达综合数据库（Gene Expression Omnibus,GEO）等公共数据库分析INHBA在胃癌组织和癌旁胃黏膜组织中表达的差异,及其表达水平对患者生存的影响。结果： 20 ng/mL以上浓度的激活素 A作用24 h可显著上调pSmad2/3水平,故选择20 ng/mL的激活素 A进行后续功能实验。激活素 A处理后胃癌细胞迁移能力增强,葡萄糖摄取和乳酸产生均增加。INHBA与多个EMT相关基因及缺氧诱导因子-1α（hypoxia-inducible factor-1α, HIF1A）、葡萄糖转运蛋白3（glucose transporter 3, GLUT3）表达呈显著正相关[SNAI1: r=0.47, P=0;SNAI2: r=0.51, P=0;波形蛋白（vimentin,VIM）: r=0.37, P=2.1×10^-14;基质金属蛋白酶（matrix metalloproteinase,MMP）2: r=0.64, P=0;MMP9: r=0.27, P=2.8×10^-8;HIF1A: r=0.45, P=0;SLC2A3: r=0.42, P=0]。激活素 A处理后,snail、slug、VIM、MMP2、GLUT3等蛋白表达升高（P<0.05）。INHBA在胃癌组织中表达明显高于癌旁胃黏膜组织,高表达INHBA的患者预后差。结论： 激活素 A可促进胃癌细胞迁移和有氧糖酵解,其机制可能是激活素 A 促进了EMT相关基因及GLUT3的表达,INHBA高表达是胃癌患者的不良预后标志。

Objective To investigate the role of activin A, a member of transforming growth factor-β superfamily cytokine, in regulating migration and aerobic glycolysis of gastric cancer cells, and the prognostic value of the expression of its coding gene inhibin βA(INHBA) in survival of gastric cancer patients. Methods The gastric cells were first titrated with various concentration of activin A and the expression of pSmad2/3 was examined by Western blot(WB) to determine the concentration range of activin A used in the study. The effect of activin A on the migration of gastric cancer cells was monitored by transwell and wound healing assays. The lactate production and glucose uptake of gastric cancer cells were followed to evaluate the role of activin A on the regulation of aerobic glycolysis. The association between activin A and epithelial mesenchymal transformation(EMT)/glycolysis related genes was analyzed in the Cancer Genome Atlas (TCGA) gastric cancer database, and further validated by WB studies. The expression of INHBA in gastric cancer and normal mucosa tissue were analyzed in TCGA, Gene Expression Omnibus(GEO) and other publicly available databases to explore the association of INHBA expression level with patients’ survival. Results The activin A at 20 ng/mL sufficiently upregulate the level of pSmad2/3, and the concentration was thus used in the study. Activin A promoted migration and aerobic glycolysis of gastric cancer cells. There was a significant positive correlation between the expression of INHBA and several EMT related genes, hypoxia inducible factor-1 α(HIF1A), glucose transporter 3 (GLUT3) [SNAI1: r=0.47, P=0;SNAI2: r=0.51, P=0; VIM: r=0.37, P=2.1×10^-14; matrix metalloproteinase(MMP)2: r=0.64, P=0; MMP9: r=0.27, P=2.8×10^-8; HIF1A: r=0.45, P=0; SLC2A3: r=0.42, P=0]. After treatment with activin A, the expression of snail, slug, vimentin, MMP2 and GLUT3 increased significantly(P<0.05). The expression of INHBA in gastric cancer was significantly higher than that in normal gastric mucosa tissue, and the prognosis of patients with higher expression of INHBA was poor. Conclusions Activin A can promote migration and aerobic glycolysis, which might attribute to its upregulation of EMT related genes and GLUT3. High level of INHBA is indicative of prognosis for gastric cancer patients.