The Enhancement of Drug Sensitivity of Human AFP-Producing Gastric Carcinoma Cell Line FU97 to Arsenic Trioxide Using AFP as Targeting siRNA

AFP-producing gastric carcinoma(APGC) are known to have a poorer prognosis and to show a higher incidence of liver metastasis than ordinary gastric carcinoma. Therefore, surgical resection, chemotherapy or radiotherapy is usually not satisfactory. In recent years, effects of arsenic trioxide (As₂O₃) on cell proliferation and induced apoptosis of solid tumors have been widely studied, while little is known about the APGC. This study was undertaken to delineate the effect of As₂O₃ on AFP gene expression ,the cell growth and apopotosis ,and to study the effect of the siRNA targeting AFP gene on the drug sensitivity of APGC cell line FU97 to As₂O₃. AFP gene sequence-specific siRNA expression vector (AFP-siRNA) and sequence-unrelated control were transfected into FU97. At 6h after transfection ,the cells were cultured with 2 mumol/L As₂O₃, with corresponding untreated cells serving as controls.The growth inhibition rate on FU97 was determined by MTT assay; Apoptosis of FU97 was investigated by DNA gel electrophore; The expressions of AFP,VEGF were determined by realtime-PCR, western blot, ELISA and chemistry luminescence. The combination of AFP-siRNA with arsenic trioxide resulted in significantly inhibitory action on growth of FU97 cells ,as well as descending of expression of AFP and VEGF.The effective siRNA targeting AFP can increase the drug sensitivity of the FU97 to arsenic trioxide.