Tripterine promotes pyroptosis of liver cancer cells by regulating ATF4/caspase-3/GSDME signaling pathway / 中国药理学通报

ABSTRACT

Aim To explore the new mechanism of triptolide (TRI) inhibiting the progression of hepatocellular carcinoma (HCC) . Methods Different concentrations (0, 0 . 5, 2, and 8 jjunol • L~) of TRI were administered to act on liver cancer cells, and then the cell phenotypes and possible mechanisms were explored using experimental methods such as CCK-8, cell cloning, Transwell, and protein immunoblotting; siRNA was used to interfere with the target gene GSDME and its role was determined. Finally, the mechanism of TRI inhibiting the growth of HCC cells in vivo was validated using a transplanted tumor model. Results TRI could inhibit the proliferation, cloning, and invasion of HCC cells, and promote cell apoptosis. Immunoblotting results showed that the expression of GSDME was significantly upregulated in HepG2 or He-pal-6 hepatocellular carcinoma after TRI treatment, while the expression of cleaved caspase-3 and PARP also significantly increased. Knocking out GSDME could partially reverse TRI-induced cell apoptosis. At the same time, cells knocked down by GSDME had stronger cloning and migration abilities, and the apoptosis rate was reduced compared to the TRI treatment group alone. In vivo experiments showed that TRI inhibited HCC tumor growth, and the TRI + siGSDME group had a faster tumor growth rate than the TRI treatment group alone did. In addition, after TRI stimulation, p-eIF2a and ATF4 in HepG2 and Hepal-6 cells significantly increased. The immunofluorescence results showed a dose-dependent increase in the number of ATF4 positive cells in HepG2 and Hepal-6 cells after TRI stimulation. Conclusion The inhibitory effect of TRI on the growth and invasion of liver cancer cells may be related to its regulation of the ATF4/caspase-3/GSDME signaling pathway and promotion of liver cancer cell apoptosis.