Nimbolide induced apoptosis by activating ERK-mediated inhibition of c-IAP1 expression in human hepatocellular carcinoma cells

Area of Science:

• Pharmacology
• Cancer Biology
• Molecular Oncology

Background:

• Nimbolide, a neem tree compound, possesses known antitumor properties.
• The specific mechanisms of nimbolide-induced apoptosis in hepatocellular carcinoma (HCC) remain largely unelucidated.
• Investigating nimbolide's effects on HCC is crucial for developing novel cancer therapies.

Purpose of the Study:

• To investigate the in vitro and in vivo effects of nimbolide on human hepatocellular carcinoma cells.
• To elucidate the molecular mechanisms underlying nimbolide-induced apoptosis and cell death.
• To evaluate the therapeutic potential of nimbolide against HCC.

Main Methods:

• Cell viability assays and cell cycle analysis in Huh-7 and PLC/PRF/5 HCC cell lines.
• Mitochondrial function assessment and Western blot analysis for apoptosis-related proteins (caspases, PARP, Bcl-2 family).
• Apoptosis antibody array, ERK pathway analysis, MEK inhibitor (U0126) treatment, and in vivo xenograft mouse model studies.

Main Results:

• Nimbolide inhibited HCC cell growth, induced G2/M phase arrest, and caused mitochondrial dysfunction.
• Apoptosis was mediated by increased cleaved caspase-3, -7, -9, PARP, Bax, and decreased Mcl-1, Bcl-2.
• Nimbolide targeted XIAP, c-IAP1, and c-IAP2, sustained ERK activation, and significantly reduced tumor growth in vivo.

Conclusions:

• Nimbolide effectively induces apoptosis and inhibits growth in human hepatocellular carcinoma cells via multiple molecular pathways.
• The compound demonstrates significant antitumor activity in both in vitro and in vivo preclinical models.
• Nimbolide presents a promising therapeutic candidate for hepatocellular carcinoma treatment.