Zeng Ling, Zhou Hai-Yun, Tang Na-Na, Zhang Wei-Feng, He Gui-Jun, Hao Bo, Feng Ya-Dong, Zhu Hong
Ling Zeng, Hai-Yun Zhou, Na-Na Tang, Wei-Feng Zhang, Gui-Jun He, Bo Hao, Ya-Dong Feng, Hong Zhu, Department of Gastroenterology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu Province, China.
World J Gastroenterol. 2016 May 28;22(20):4868-80. doi: 10.3748/wjg.v22.i20.4868.
To investigate the influence of phosphatidylinositol-3-kinase protein kinase B (PI3K/AKT)-HIF-1α signaling pathway on glycolysis in esophageal carcinoma cells under hypoxia.
Esophageal carcinoma cell lines Eca109 and TE13 were cultured under hypoxia environment, and the protein, mRNA and activity levels of hypoxia inducible factor-1 alpha (HIF-1α), glucose transporter 1, hexokinase-II, phosphofructokinase 2 and lactate dehydrogenase-A were determined. Supernatant lactic acid concentrations were also detected. The PI3K/AKT signaling pathway was then inhibited with wortmannin, and the effects of hypoxia on the expression or activities of HIF-1α, associated glycolytic enzymes and lactic acid concentrations were observed. Esophageal carcinoma cells were then transfected with interference plasmid with HIF-1α-targeting siRNA to assess impact of the high expression of HIF-1α on glycolysis.
HIF-1α is highly expressed in the esophageal carcinoma cell lines tested, and with decreasing levels of oxygen, the expression of HIF-1α and the associated glycolytic enzymes and the extracellular lactic acid concentration were enhanced in the esophageal carcinoma cell lines Eca109 and TE13. In both normoxia and hypoxic conditions, the level of glycolytic enzymes and the secretion of lactic acid were both reduced by wortmannin. The expression and activities of glycolytic enzymes and the lactic acid concentration in cells were reduced by inhibiting HIF-1α, especially the decreasing level of glycolysis was significant under hypoxic conditions.
The PI3K/AKT pathway and HIF-1α are both involved in the process of glycolysis in esophageal cancer cells.
探讨磷脂酰肌醇-3激酶蛋白激酶B（PI3K/AKT）-低氧诱导因子-1α（HIF-1α）信号通路对低氧环境下食管癌细胞糖酵解的影响。
将食管癌细胞系Eca109和TE13置于低氧环境中培养，检测低氧诱导因子-1α（HIF-1α）、葡萄糖转运蛋白1、己糖激酶-II、磷酸果糖激酶2和乳酸脱氢酶-A的蛋白、mRNA及活性水平，同时检测上清液乳酸浓度。然后用渥曼青霉素抑制PI3K/AKT信号通路，观察低氧对HIF-1α表达或活性、相关糖酵解酶及乳酸浓度的影响。接着用靶向HIF-1α的小干扰RNA干扰质粒转染食管癌细胞，评估HIF-1α高表达对糖酵解的影响。
HIF-1α在受试食管癌细胞系中高表达，且随着氧浓度降低，食管癌细胞系Eca109和TE13中HIF-1α及相关糖酵解酶的表达和细胞外乳酸浓度均升高。在常氧和低氧条件下，渥曼青霉素均降低了糖酵解酶水平和乳酸分泌。抑制HIF-1α可降低细胞中糖酵解酶的表达和活性以及乳酸浓度，尤其是在低氧条件下糖酵解水平降低显著。
PI3K/AKT通路和HIF-1α均参与食管癌细胞的糖酵解过程。
