Lysionotin promoted apoptosis of hepatocellular carcinoma cells via inducing autophagy.

BACKGROUND: Hepatocellular carcinoma is a prevalent malignant tumor with a high mortality rate. Natural plants hold promise for its treatment, however, the mechanism of lysionotin induced apoptosis in liver cancer cells unclearly. This study aims to investigate the microenvironment alterations and the efficacy of lysionotin in liver cancer. METHODS: Transmission electron microscopy, and laser confocal microscopy were employed to investigate the effect of lysionotin on autophagy in HCC cells. The molecular mechanism through which lysionotin induces autophagy and autophagy-induced apoptosis was ascertained by transcriptome sequencing, immunoblotting and Hoechst 33258 staining. RESULTS: RNA sequencing analysis, electron microscopy and laser confocal microscopy revealed that lysionotin initiate autophagy in liver cancer cells. Immunoblotting indicated that lysionotin markedly enhances the activation of LC3-II in HCC cells, resulting in the activation of key effector molecules ATG12, Beclin-1 and the degradation of P62. Combined with autophagy inhibitors CQ and 3-MA significantly inhibited lysionotin-induced cell apoptosis. Immunoblotting and Hoechst staining disclosed that the activation of autophagy by lysionotin might be associated with the suppression of the mTOR-AKT signaling pathway. The treatment of mTOR inhibitor RAPA and activator 1485 demonstrated that inhibiting mTOR activation significantly augments the pro-apoptotic effect of lysionotin on liver cancer cells, while mTOR activator could rescue the effect of lysionotin on cells. CONCLUSIONS: The findings suggest that the activation of autophagy by lysionotin may represent one of the pivotal mechanisms underlying its therapeutic efficacy against HCC and its synergistic enhancement of RAPA's antitumor effects.