glycycoumarin and Carcinoma--Hepatocellular

Glycycoumarin (GCM) is a major bioactive coumarin compound isolated from licorice and the anti-cancer activity of GCM has not been scientifically addressed. In the present study, we have tested the anti-liver cancer activity of GCM using both in vitro and in vivo models and found for the first time that GCM possesses a potent activity against liver cancer evidenced by cell growth inhibition and apoptosis induction in vitro and tumor reduction in vivo. Mechanistically, GCM was able to bind to and inactivate oncogenic kinase T-LAK cell-originated protein kinase (TOPK), which in turn led to activation of p53 pathway. Our findings supported GCM as a novel active compound that contributed to the anti-cancer activity of licorice and TOPK could be an effective target for hepatocellular carcinoma (HCC) treatment.

Topics: Animals; Antineoplastic Agents; Apoptosis; Biomarkers, Tumor; Carcinoma, Hepatocellular; Cell Proliferation; Coumarins; Humans; Liver Neoplasms; Male; Mice; Mice, Inbred BALB C; Mice, Nude; Mitogen-Activated Protein Kinase Kinases; Phosphorylation; Protein Conformation; Tumor Cells, Cultured; Tumor Suppressor Protein p53; Xenograft Model Antitumor Assays

Licorice, a traditional Chinese medicine, has been used to treat various diseases, including liver disease, for centuries. However, the chemical basis and biological mechanisms underlying the biological functions of licorice remain elusive. The purpose of the current study was to test the hepatoprotective effect of glycycoumarin (GCM), a representative coumarin in licorice, using animal models of both chronic and acute alcoholic liver injury. C57BL/6J mice were used to evaluate the hepatoprotective effect of GCM on liver injury induced by either chronic or acute ethanol exposure. AML-12 and HepG2 cells were utilized to determine the functional role of Nrf2 in the hepatoprotective effect of GCM and to decipher the mechanisms of GCM-induced Nrf2 activation. We found that treatment with GCM leads to a significant reduction in hepatotoxicity in response to either chronic or acute ethanol exposure. Further mechanistic investigations reveal that activation of Nrf2 via the p38 pathway and induction of autophagy by GCM contribute to its hepatoprotective activity. In addition, we demonstrate that p62 upregulation by a transcriptional mechanism also contributes to Nrf2 activation via a positive feedback loop. Our study has identified GCM as a novel active ingredient that contributes to the hepatoprotective activity of licorice.

Topics: Animals; Apoptosis; Autophagy; Blotting, Western; Carcinoma, Hepatocellular; Cell Proliferation; Cells, Cultured; Central Nervous System Depressants; Coumarins; Ethanol; Fluorescent Antibody Technique; Liver; Liver Neoplasms; Male; Mice; Mice, Inbred C57BL; NF-E2-Related Factor 2; Oxidative Stress; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger