Simvastatin Inhibits the Warburg Effect and Improves the Mechanism of Metastasis and Invasion of Sorafenib-resistant Liver Cancer Cells

OBJECTIVE To explore the mechanism of simvastatin to improve the metastatic invasion of sorafenib-resistant liver cancer cells after inhibiting the Warburg effect. METHODS Sorafenib-resistant human liver cancer cell line SMMC-7721/S(5 μmol·L^-1 sorafenib-resistant) was divided into control group, sorafenib group and simvastatin group. The sorafenib group was treated with 5 μmol·L^-1 sorafenib, and the simvastatin group was treated with 10 μmol·L^-1 and 20 μmol·L^-1 simvastatin. CCK-8 method was used to detect changes in SMMC-7721/S cell viability. Flow cytometry after PI staining was used to detect cell cycle changes. In vitro cell scratch test was used to detect cell migration. Transwell cell test was used to detect cell invasion and metastasis. Western blotting was used to detect the key enzymes of Warburg effect, hexokinase, pyruvate kinase, lactate dehydrogenase, pyruvate dehydrogenase and citrate synthase expression changes. The kit detected the level of lactic acid production in the culture medium. ECAR detected the change in the pressure of glycolysis in the cell. And the 929 oxygen system detected the level of oxygen absorption by the cell. RESULTS The cell viability test results showed that the cell viability of the sorafenib group was not significantly changed compared with the control group, and there was no significant difference in the cell cycle. The expression of hexokinase, pyruvate kinase, lactate dehydrogenase, pyruvate dehydrogenase and citrate synthase enzymes in the cells did not change, and there was no significant difference in the level of lactic acid and oxygen absorption in the medium. The cell viability was significantly down-regulated in the simvastatin group, and the cell cycle was blocked at the G0/G1 phase, which was significantly different from the sorafenib group(P<0.05), while the cell migration, metastasis, and invasion ability was significantly weakened(P<0.05), the levels of hexokinase, pyruvate kinase, lactate dehydrogenase, pyruvate dehydrogenase and enzymes in the cells were lower than those in the sorafenib group(P<0.05), the level of lactic acid in the medium of the simvastatin group was reduced, and the level of oxygen absorption was increased, which was significantly different from the sorafenib group(P<0.05). CONCLUSION Simvastatin can inhibit the metastasis and invasion of liver cancer cells by improving the Warburg effect of drug-resistant liver cancer cells.