Casticin Potentiates TRAIL-Induced Apoptosis of Gastric Cancer Cells through Endoplasmic Reticulum Stress

作者：Yuan Zhou, Tian Li, Lingzhi Long, Meifang Quan, Fei Liu, Jianguo Cao · 发表于：PLoS ONE · 年份：2013 · DOI：10.1371/journal.pone.0058855 · 被引用次数：55 · 研究领域：Cell death mechanisms and regulation、Toxin Mechanisms and Immunotoxins、NF-κB Signaling Pathways

BACKGROUND: Casticin is one of the main active components obtained from Fructus Viticis and has been reported to exert anti-carcinogenic activity on a variety of cancer cells but the precise mechanism underlying this activity remains unclear. MATERIALS AND METHODS: Apoptotic activities of casticin (1.0 µmol/l) and TRAIL (25, 50 ng/ml) alone or in combination in the gastric cancer cell lines BGC-823, SGC-7901 and MGC-803 were detected by the use of a cell apoptosis ELISA detection kit, flow cytometry (FCM) with propidium iodide (PI) staining and activities of caspase-3, -8 and -9 by ELISA and cleavage of polyADP-ribose polymerase (PARP) protein using western blot analysis. Death receptors (DR) expression levels were evaluated using FCM analysis and western blotting. 2', 7'-dichlorofluorescein diacetate (DCFH-DA) was used as a probe to measure the increase in reactive oxygen species (ROS) levels in cells. Multiple interventions, such as siRNA transfection and pharmacological inhibitors were used to explore the mechanisms of these actions. RESULTS: Subtoxic concentrations of casticin significantly potentiated TRAIL-induced cytotoxicity and apoptosis in BGC-823, SGC-7901 and MGC-803 cells. Casticin dramatically upregulated DR5 receptor expression but had no effects on DR4 or decoy receptors. Deletion of DR5 by siRNA significantly reduced the apoptosis induced by the co-application of TRAIL and casticin. Gene silencing of the CCAAT/enhancer binding protein homologous protein (CHOP...