[Curcumin promotes apoptosis of esophageal squamous carcinoma cell lines through inhibition of NF-kappaB signaling pathway].

BACKGROUND & OBJECTIVE: Activation of NF-kappaB signaling pathway plays a critical role in the initiation and progression of carcinogenesis. However, the role of NF-kappaB pathway in esophageal squamous cell carcinoma (ESCC) has not been fully elucidated. Studies have shown that curcumin possesses anti-infection and anti-oxidation effects. This study was to evaluate whether curcumin could induce apoptosis through inhibition of NF-kappaB signaling pathway in ESCC cells. METHODS: Expressions of pIkappaBalpha and Bcl-2 were detected using Western blott after incubation of ESCC cells with curcumin (50 micromol/L) at different time points. Apoptosis and the number of viable ESCC cells were analyzed using flow cytometry and MTT, respectively, after the treatment of curcumin, 5-FU, or the combination of curcumin and 5-FU. RESULTS: In two ESCC cell lines, EC9706 and Eca109,curcumin inhibited IkappaBalpha phosphorylation and Bcl-2 in a time-dependent manner; curcumin alone increased cell apoptosis (P<0.05), and the effect became more prominent when it was combined with 5-FU (P<0.05); curcumin plus 5-FU exerted a stronger inhibition effect on cell proliferation than curcumin alone (P<0.05) or 5-FU alone (P<0.05). CONCLUSION: Curcumin inhibits the phosphorylation of IkappaBalpha, leading to suppression of proliferation, induction of apoptosis and an increase of the sensitivity of ESCC cell lines towards 5-FU.