Objective: To investigate the role of α-enolase (ENO1) in regulating glucose metabolism and cell growth in human glioma cells.
Methods: Glucose uptake and lactate generation were assessed to evaluate the changes in glucose metabolism in human glioma U251 cells with small interfering RNA (siRNA)-mediated ENO1 knockdown. MTT assay and 5-ethynyl-2'-deoxyuridine (EdU) staining were used to examine the cell growth and cell cycle changes following siRNA transfection of the cells.
Results: Transfection of U251 cells with siRNA-ENO1 markedly reduced glucose uptake (P=0.023) and lactate generation (P=0.007) in the cells and resulted in significant suppression of cell proliferation (*P<0.05) since the second day following the transfection. Transfection with siRNA-ENO1 also obviously suppressed cell cycle G1/S transition in the cells (P=0.0425). The expressions of HK2 and LDHA, the marker genes for glucose metabolism, were significantly down-regulated in the cells with siRNA-mediated ENO1 knockdown.
Conclusion: ENO1 as a potential oncogene promotes glioma cell growth by positively modulating glucose metabolism.
目的: 探讨抑制α-烯醇化酶（ENO1）表达对胶质瘤细胞糖代谢和细胞生长的影响。
方法: 在胶质瘤细胞U251中，利用siRNA抑制ENO1表达后，利用葡萄糖摄取和乳酸生成实验检测糖代谢水平的改变；利用3-（4，5-dimethyl-2-thiazolyl）-2，5-diphenyl-2-H-tetrazolium bromide（MTT）和5-Ethynyl-2'-deoxyuridine（EDU）着色的方法检测细胞增殖和细胞周期的改变。Western blot活性分析抑制ENO1表达糖代谢标志基因Hexokinase 2（HK2）和Lactate dehydrogenase A（LDHA）基因的表达水平改变。
结果: 成功筛选了抑制ENO1的siRNA片段。在抑制ENO1表达，胶质瘤U251细胞摄取葡萄糖的能力明显降低（P=0.023）以及乳酸生成能力明显下降（P=0.007）。进一步，MTT和EDU着色分析显示，在抑制ENO1表达后，细胞的增殖能力从第2天开始明显降低（P＜0.05）；除此之外，细胞周期G1/S转化能力明显抑制（P=0.0425）。机制分析显示，ENO1下调后糖代谢标志基因HK2和LDHA表达也明显下降。
结论: ENO1作为候选癌基因，通过正调控葡萄糖代谢从而促进了胶质瘤细胞的生长。