Ribosome-inactivating Protein MAP30 Isolated from Momordica CharantiaL. Induces Apoptosis in Hepatocellular Carcinoma Cells
Yiping Zhou, Di Yang, Zihao Qiang, Yanfa Meng, Yanfa Meng, Ruigang Li, Fan Xiang, Wei Zhao, Yao Meng, Yao Meng
Abstract
BACKGROUND: Ribosome-inactivating proteins (RIPs) have been reported to exert antitumor and anti-virus activities. A recent patent CN202011568116.7 has developed a new method to prepare Momordica anti-HIV protein of 30 kDa (MAP30). MAP30 is a type I RIP, which kills various tumor cells through the N-glycosidase activity and irreversibly inhibits protein synthesis. OBJECTIVE: To assess the potential role of MAP30 in inducing apoptosis of human hepatocellular carcinoma HCC-LM3 cells and elucidate the molecular mechanism of MAP30. METHODS: CCK-8 assay was used to assess the proliferation of HCC-LM3 cells. Flow cytometry was used to measure the cycle, the level of ROS and apoptosis in HCC-LM3 cells. Western blots was used to measure protein levels. RESULTS: Treatment with MAP30 reduced survival and proliferation of human liver cancer HCCLM3 cells in a dose-dependent manner. PI staining showed cell cycle arrest in G0/G1 phase. Furthermore, MAP30 increased the level of ROS in HCC-LM3 cells in 24 h treatment. To further confirm the role of MAP30 in inducing cell apoptosis, immunoblotting was carried out to detect the change of apoptosis-related proteins including PARP poly (ADP-ribose) polymerase (PARP- 1), Casepase3 and Cleaved-Caspase9. We found that PARP-1 and Caspase-3 were downregulated, whereas Cleaved-Caspase9 was up-regulated in HCC-LM3 cells treated with MAP30. CONCLUSION: This study indicated that MAP30 has the potential to be a novel therapeutic agent for human hepatocellular carcinoma.