辣椒素促进食管鳞癌细胞凋亡的体外研究

OBJECTIVE: This study was to detect the status of NF-κB signaling pathway in two ESCC cell lines and evaluate whether capsaicin induced apoptosis through inhibition of NF-κB signaling pathway in ESCC cells. METHODS: Western blot was used to determine the protein levels of inhibitor-κBα (IκBα) and phosphorylated-IκBα (pIκBα), p50 and p65 in the nuclear extracts. Cytoplasmic extracts were examined for the expression of pIκBα and Bcl-2 using Western blot after the cells were treated with different concentration capsaicin. DNA-binding activity and the change of DNA-binding activity after treated with capsaicin were evaluated by electrophoretic mobility gel shift assay (EMSA). ESCC cells were treated with capsaicin, 5-FU or combinations thereof for 72h and then analyzed cell apoptosis by flow cytometry. RESULTS: Two ESCC cell lines had expression of IκBα and pIκBα in the cytoplasm, p50 and p65 in the nuclear. The results also indicated that capsaicin inhibited IκBα phosphorylation and Bcl-2 in two ESCC cell lines in a concentration-dependent manner. EMSA showed high DNA-binding activity in two ESCC cell lines and capasicin suppressed the NF-κB-DNA-binding in a concentration-dependent manner. Capsaicin alone could increase cell apoptosis (P<0.05). While combination with 5-FU, the results were more prominence (P<0.05). CONCLUSION: Capsaicin inhibits the phosphorylation of IκBα and downregulates the activation of NF-κB signaling pathway, leading to suppression of proliferation, induction of apoptosis and increasing the sensitivity of 5-FU in ESCC cell lines.