异丙酚通过GLUT4抑制肺癌糖酵解及肿瘤进展

Propofol inhibits glycolysis and tumor progression in lung cancer through GLUT4

目的 研究异丙酚对肺癌糖酵解的作用,并进一步探究其通过葡萄糖转运体4(Glucose transporter 4,GLUT4)抑制肺癌糖酵解的潜在机制。方法 培养A549人源肺癌细胞系和LLC鼠源肺癌细胞系,实验分组设置为空白对照组(Control组)和异丙酚(10μmoL)组(Propofol组)。采用CCK-8检测细胞活力;免疫荧光检测细胞及肿瘤组织Ki-67表达水平;细胞外酸化率(Extracellular acidification rate, ECAR)和线粒体耗氧量(Mitochondrial oxygen consumption, OCR)实验检测细胞代谢水平;ELISA检测细胞乳酸和丙酮酸含量;采用CB-Dock在线工具进行分子对接实验,检测GLUT4与异丙酚结合能力;葡萄糖摄取试剂盒检测葡萄糖摄取情况;Western blot检测各组的GLUT4、HK2和PFK1的蛋白表达变化。结果 在10μmoL异丙酚的作用下,A549细胞(0.661±0.052)和LLC细胞(0.632±0.033)的细胞活力被明显抑制(P<0.001)。与对照组相比,A549和LLC阳性细胞的Ki-67荧光平均强度(0.663±0.064和0.540±0.070)均被明显抑制(P<0.001)。ELISA结果显示,与对照组相比,异丙酚组乳酸和丙酮酸水平降低(P<0.001),在异丙酚的作用下,细胞的葡萄糖摄取能力降低(P<0.001)。采用CB-Dock在线工具进行分子对接实验,检测出GLUT4与异丙酚结合力最强,Western blot结果显示GLUT4及其下游HK2和PFK1蛋白表达水平下降。瞬时转染敲低GLUT4后,细胞乳酸(P<0.001)和丙酮酸含量(P<0.01)下降,葡萄糖摄取能力降低,异丙酚对糖酵解的抑制作用消失。肺肿瘤组织中,给药组的肿瘤大小明显小于模型组(P<0.001)。与模型组相比,异丙酚组乳酸含量和丙酮酸含量降低(P<0.001)。结论 异丙酚能够通过抑制肺癌细胞糖酵解抑制肺癌细胞增殖及荷瘤小鼠肺癌进展,其机制可能与靶向GLUT4影响肺癌细胞糖酵解有关。

Objective The objective of this study was to investigate the effects of propofol on glycolysis of lung cancer,and to further explore its potential mechanism of inhibiting glycolysis in lung cancer through glucose transporter 4(GLUT4).Methods Human lung cancer A549 cells and mouse lung cancer LLC cells were cultured,and the experimental groups were set as the blank control group(Control group)and propofol(10μmol/L)group(Propofol group).The CCK-8 assay was used to detect cell viability;Immunofluorescence(IF)was used to detect the expression of Ki-67 in lung cancer cells and A549 cell xenografts.Extracellular acidification rate(ECAR)and mitochondrial oxygen consumption(OCR)assays were used to detect the cellular metabolic levels;ELISA was used to detect the cell lactate and pyruvate content;Molecular docking experiments were used to detect the binding ability of GLUT4 with propofol using CB-Dock online tool;The glucose uptake kit was used to detect glucose uptake;Western blot was used to detect the expression of GLUT4,HK2,and PFK1 proteins in lung cancer cells.Results The cell viability of A549 cells(0.661±0.052)and LLC cells(0.632±0.033)in the propofol group was significantly inhibited by 10μmol/L of propofol in lung cancer cells(P<0.001).Compared with the control group,the average fluorescence intensity of Ki-67 in A549 and LLC positive cells(0.663±0.064 and 0.540±0.070)was significantly suppressed(P<0.001).The ELISA results showed that compared with the control group,the levels of lactate and pyruvate in the propofol group decreased(P<0.001),and under the action of propofol,the glucose uptake ability of cells decreased(P<0.001).Molecular docking experiments using the CB-Dock online tool showed that GLUT4 had the strongest binding force with propofol.The results of Western blot showed a decrease in the expression of GLUT4 and its downstream HK2 and PFK1 proteins.After transient transfection and knockdown of GLUT4,cellular lactate(P<0.001)and pyruvate content(P<0.01)decreased,glucose uptake capacity reduced,and the inhibitory effect of propofol on glycolysis disappeared.In A549 cell xenografts,the weight of xenografts in the propofol group was significantly smaller than that of the model group(P<0.001).Compared with the model group,the lactate content and pyruvate content decreased in the propofol group(P<0.001).Conclusion Propofol can inhibit the proliferation of lung cancer cells and the progression of A549 cell xenografts in bearing mice by inhibiting the glycolysis of lung cancer cells,and its mechanism may be related to the targeted effect of GLUT4 on the glycolysis of lung cancer cells.