Inhibitive effects of 15-deoxy-Δ12,14-prostaglandin J2 on hepatoma-cell proliferation through reactive oxygen species-mediated apoptosis

Objective: 15-Deoxy-Delta(12,14)-prostaglandin J(2) (15d-PGJ(2)) induces reactive oxygen species (ROS)-mediated apoptosis in many malignant cells, which has not been studied in hepatoma cells. In this study, we investigated whether 15d-PGJ(2) induced apoptosis in hepatocellular carcinoma (HCC) associated with ROS. Materials and methods: The LM3, SMMC-7721, and Huh-7 HCC cell lines were treated with 15d-PGJ(2) (5-40 mu M) for 24, 48, and 72 hours. Cholecystokinin 8 was used to detect the cytotoxicity of 15d-PGJ(2). Flow cytometry, Hoechst staining, and Western blotting were used to analyze apoptosis. ROS were combined with the fluorescent probe dihydroethidium and then observed by fluorescence microscopy and flow cytometry. Activation of JNK and expression of Akt were detected by Western blotting. Results: 15d-PGJ(2) inhibited HCC cell proliferation and induced apoptosis in a dose-and time-dependent manner. Apoptosis was mainly induced via an intrinsic pathway and was ROS-dependent, and was alleviated by ROS scavengers. ROS induced JNK activation and Akt downregulation in HCC cells. Conclusion: 15d-PGJ(2) induced ROS in HCC cell lines, and inhibition of cell growth and apoptosis were partly ROS-dependent.