Effects Of Hydroxycamptothecin On The Energy Metabolism Of Hepatocellular Carcinoma HepG2 Cells By Inhibiting HIF-1?

OBJECTIVE:To investigate the effect of hydroxycamptothecin(HCPT)on energy metabolism in human hepatoma HepG2 cells,and to examine the mechanism of HCPTTs effect on the energy metabolism of HepG2 cells by inhibiting the expression of HIF-la protein.METHODS:The effect of HCPT on the proliferation of HepG2 cells was determined by MTT assay.The effect of HCPT on HepG2 cell apoptosis was detected by Annexin V-FITC/PI staining.The activity of Caspase-3 was detected by spectrophotometry.The glucose uptake of each group was determined.Energy metabolites lactic acid(LD)adenosine triphosphate(ATP)and other related en,ergy metabolism parameters and glycolytic key enzymes hexokinase(HK),pyruvate kinase (PK),lactate dehydrogenase(LDH)activity;unmunoblotting The expression levels of Bax,Bcl-2,HIF-1?,GLUT-1 and LDH proteins were determined by t he method.RESULTS:HCPT can inhibit the proliferation of HepG2 cells,and the cell proliferation activity decreases with the increase of drug dosage.Compared with the control group,the early apoptosis rate of the drug-administered group increased,and the Caspase-3 activity gradually increased.As the dose increases,HCPT can increase the expression of Bax,and at the same time,the expression of Bcl-2 decreases with increasing dose.HCPT can inhibit(reduce)ATP production,LD production and Glu uptake in a dose-dependent manner;HCPT can inhibit the activity of HK and LDH in a dose-dependent manner,but the effect on PK is not obvious.Low-dose,medium-dose,and high-dose HCPT reduced the expression of GLUT-1,which was statistically significant compared with the control group;the effect on LDH is significant;HCPT can inhibit the expression of HIF-la,and the expression of HIF-la is inhibited gradually with increasing strengthen.Conclusion:HCPT can effectively inhibit the proliferation of HepG2 cells and promote cell apoptosis.HCPT inhibits the uptake of Glu by HepG2 cells by inhibiting the expression of GHUT-1 and LDH by inhibiting the expression of HIF-la.In addition,HCPT can also reduce HK,LDH by inhibiting the expression of HIF-1a.The activity affects the glycolytic pathway and reduces the production of the energy substance ATP and the metabolite LD.The above studies can show that HCPT can inhibit the energy metabolism of HepG2 cells by inhibiting HIF-la,thereby inhibiting the proliferation of tumor cells and promoting the apoptosis of tumor cells.The above-mentioned proteins and key en2ymes of glycolysis can be used as therapeutic targets.Cut off the energy metabolism of tumor cells.