title: Genistein enhances TRAIL-induced apoptosis through inhibition of p38 MAPK signaling in human hepatocellular carcinoma Hep3B cells.
abstract: The cytotoxic effect of the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is limited in some carcinoma cancer cells. However, it was found that treatment with TRAIL in combination with nontoxic concentrations of genistein sensitized TRAIL-resistant human hepatocellular carcinoma Hep3B cells to TRAIL-mediated apoptosis. Combined treatment with genistein and TRAIL-induced chromatin condensation and sub-G1 phase DNA content. These indicators of apoptosis were correlated with the induction of caspase activity that resulted in the cleavage of poly(ADP-ribose) polymerase (PARP). Both cell viability and the cleavage of PARP induced by combined treatment were significantly inhibited by caspase-3, -8 and -9 inhibitors, which demonstrates the important roles of caspases in the observed cytotoxic effects. Genistein treatment also triggered the inhibition of p38-beta mitogen-activated protein kinase (MAPK) activation. Pretreatment with SB203580 resulted in significantly increased sub-G1 population and loss of mitochondrial membrane potential (MMP) in TRAIL-induced apoptosis. By contrast, overexpression of p38 MAPK protected apoptosis by co-treatment with genistein and TRAIL, suggesting that the p38 MAPK act as key regulators of apoptosis in response to treatment with a combination of genistein and TRAIL in human hepatocellular carcinoma Hep3B cells.
authors.affiliation: Department of Biomaterial Control, Dongeui University Graduate School, Dongeui University College of Oriental Medicine, Busan, Republic of Korea.
authors.forename: Cheng-Yun
authors.initials: CY
authors.lastname: Jin
authors.forename: Cheol
authors.initials: C
authors.lastname: Park
authors.forename: Gi-Young
authors.initials: GY
authors.lastname: Kim
authors.forename: Su-Jae
authors.initials: SJ
authors.lastname: Lee
authors.forename: Wun-Jae
authors.initials: WJ
authors.lastname: Kim
authors.forename: Yung Hyun
authors.initials: YH
authors.lastname: Choi
mesh_terms: D016588:Anticarcinogenic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D006528:Carcinoma, Hepatocellular / Q000473:pathology; D020169:Caspases / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation / Q000187:drug effects; D015971:Gene Expression Regulation, Enzymologic; D019833:Genistein / Q000008:administration & dosage / Q000494:pharmacology*; D006801:Humans; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D015398:Signal Transduction; D053221:TNF-Related Apoptosis-Inducing Ligand / Q000008:administration & dosage / Q000494:pharmacology*; D048051:p38 Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism*
chemical_list: D016588:Anticarcinogenic Agents; D053221:TNF-Related Apoptosis-Inducing Ligand; D019833:Genistein; D048051:p38 Mitogen-Activated Protein Kinases; D020169:Caspases