Effect on radiation-induced apoptosis of HeLa cells by inhibiting expression of NF-κB

Background and purpose: NF-κB is activated by tumor necrosis factor,some chemotherapeutic agents,and ionizing radiation.The activation of NF-κB could result in inhibition of apoptosis.NF-κB,regulated by PDTC(pyrrolidine dithiocarbamate),is a specific inhibitor of NF-κB.The purpose of our study was to explore the impact of inhibiting expression of NF-κB on radiation-induced apoptosis of uterine cervix cancer HeLa cells.Methods:Inhibition of NF-κB in HeLa cells was performed by treatment with 100 μmol/L PDTC for 2 hours.Cells were irradiated at 0,2,4 and 6 Gy with or without PDTC.The expression of NF-κB in nuclear was determined by western blot,and apoptosis was evaluated by using the TUNEL assay.Cell proliferation was evaluated by using MTT assay.Results:NF-κB activation was induced by radiation and inhibited by PDTC.Inhibition of radiation-induced NF-κB activation resulted in inhibiting cell proliferation(P0.05)and increased apoptosis index(P0.001) in HeLa cells.Conclusions:Inhibition of the expression of NF-κB increases radiation-induced apoptosis in uterine cervix cancer HeLa cells and enhances the cell response to radiation.