Licochalcone B Extracted from Glycyrrhiza uralensis Fisch Induces Apoptotic Effects in Human Hepatoma Cell HepG2

The present study explored the molecular mechanism by which licochalcone B induces the cell cycle arrest and apoptosis in human hepatoma cell HepG2. Initial extraction and identification were performed by HPLC, UPLC-TOF-MS/MS, and NMR analysis, respectively. Licochalcone B inhibited the HepG2 growth with IC₅₀ (110.15 μM) after 24 h, caused morphological distortion, and seized the cell cycle in the G2/M phase (cell arrest in G2/M:43.1 ± 2.2% for 120 μM versus 23.7 ± 1.2% for control), as well as induced apoptosis and intracellular ROS generation. Furthermore, exposure to licochalcone B markedly affected the cell cycle (up/down regulation) at mRNA and protein levels. Apoptosis was induced through the activation of receptor-mediated and mitochondrial pathways. The inhibition of Caspase 8 and Caspase 9 proteins abolished the licochalcone B induced apoptosis. The present work suggested that licochalcone B may further be identified as a potent functional food component with specific health benefits.

Natural Compound Licochalcone B Induced Extrinsic and Intrinsic Apoptosis in Human Skin Melanoma (A375) and Squamous Cell Carcinoma (A431) Cells

Licochalcone B (Lico B), which is normally isolated from the roots of Glycyrrhiza inflata (Chinese Licorice), generally classified into organic compounds including retrochalcones. Potential pharmacological properties of Lico B include anti-inflammatory, anti-bacterial, anti-oxidant, and anti-cancer activities. However, its biological effects on melanoma and squamous cell carcinoma (SCC) are unknown. Based on these known facts, this study investigated the role of Lico B in apoptosis, through the extrinsic and intrinsic pathways and additional regulation of specificity protein 1 in human skin cancer cell lines. Annexin V/7-aminoactinomycin D staining, western blot analysis, mitochondrial membrane potential assay, and an anchorage-independent cell transformation assay demonstrated that Lico B treatment of human melanoma and SCC cells significantly inhibited cell proliferation and induced apoptotic cell death. More specifically, Lico B induced apoptosis through the regulation of specificity protein 1 and apoptosis-related proteins including CCAAT/enhancer-binding protein homologous protein, death receptors, and poly (ADP-ribose) polymerase. These results indicate that Lico B has apoptotic effect on A375 and A431 skin cancer cells, suggesting the potential value of Lico B for the treatment of human melanoma and SCC. Copyright © 2017 John Wiley & Sons, Ltd.