Curcumin Sensitizes Hepatocellular Carcinoma Cells to Radiation via Suppression of Radiation-Induced NF-κB Activity

• Published in: BioMed research international 2015-01, Vol.2015 (2015), p.1-7
• Main Authors: Hwang, Jeng-Jong, Liu, Tsu-Te, Liu, Yu-Chang, Hsu, Fei-Ting
• Format: Article
• Language: English
• Subjects: Animals; Apoptosis - drug effects; Apoptosis - radiation effects; Cancer cells; Carcinoma, Hepatocellular - drug therapy; Carcinoma, Hepatocellular - genetics; Carcinoma, Hepatocellular - pathology; Carcinoma, Hepatocellular - radiotherapy; Cell Proliferation - drug effects; Cell Proliferation - radiation effects; Curcumin - administration & dosage; Drug therapy; Gene Expression Regulation, Neoplastic - drug effects; Gene Expression Regulation, Neoplastic - radiation effects; Health aspects; Hep G2 Cells; Hepatoma; Humans; I-kappa B Proteins - genetics; Liver Neoplasms - drug therapy; Liver Neoplasms - genetics; Liver Neoplasms - pathology; Liver Neoplasms - radiotherapy; Membrane Potential, Mitochondrial - drug effects; Membrane Potential, Mitochondrial - radiation effects; Methods; Mice; NF-kappa B - biosynthesis; NF-kappa B - genetics; NF-KappaB Inhibitor alpha; Radiotherapy; Turmeric; Xenograft Model Antitumor Assays
• ISSN: 2314-6133; 2314-6141
• DOI: 10.1155/2015/363671

The effects and possible underlying mechanism of curcumin combined with radiation in human hepatocellular carcinoma (HCC) cells in vitro were evaluated. The effects of curcumin, radiation, and combination of both on cell viability, apoptosis, NF-κB activation, and expressions of NF-κB downstream effector proteins were investigated with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), NF-κB reporter gene, mitochondrial membrane potential (MMP), electrophoretic mobility shift (EMSA), and Western blot assays in Huh7-NF-κB-luc2, Hep3B, and HepG2 cells. Effect of I kappa B alpha mutant (IκBαM) vector, a specific inhibitor of NF-κB activation, on radiation-induced loss of MMP was also evaluated. Results show that curcumin not only significantly enhances radiation-induced cytotoxicity and depletion of MMP but inhibits radiation-induced NF-κB activity and expressions of NF-κB downstream proteins in HCC cells. IκBαM vector also shows similar effects. In conclusion, we suggest that curcumin augments anticancer effects of radiation via the suppression of NF-κB activation.