GLP1R and hepatocellular carcinoma: In addition, Ex-4 was also demonstrated to downregulate hepatic steatosis in HepG2 human HCC cells, via GLP-1R-mediated activation of PKA [58], while Krause et al. provided evidence that Ex-4 induced autophagy and prevented HepG2 cell regrowth via the modulation of mTOR signaling in HCC [59].