Influence of smoothened small interfering RNA on proliferation and apoptosis of human esophageal carcinoma cell line EC9706

Objective To investigate the proliferation and apoptosis of blocking Hh signaling on Smo gene locus in esophageal cancer cell.Methods The small interfering RNA (siRNA) was transfected into esophageal squamous carcinoma cell EC9706.reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blotting were used to detect the levels of Smo and Gli1 mRNA and protein.Methyl thiazol tetrazolium (MTT) assay and flow cytometry were used to detect the cell proliferation and apoptosis.Results (1) Compared with the control groups,after transfectitoa of Smo siRNA for 24,48 and 72 h,the levels of Smo mRNA were 4.20 ± 1.10,2.80 ± 1.10 and 1.00 ± 0.71,Gli1 mRNA 4.60 ± 1.34,3.00 ±0.71 and 1.20 ± 1.10,which were knocked down significantly (P ＜0.05).(2) After transfection of Smo siRNA for 72 h,the levels of Smo and Gli protein were 0.330 ±0.016 and 0.324 ±0.021 respectively,which were significantly lower than the control groups (P ＜ 0.05).(3) The inhibition rate of cell proliferation was (88.06 ± 7.56) ％ after transfection of 72 h,which was significantly inhibited compared with the control groups.(4) The number of apoptosis cells was also greatly increased after Smo siRNA transfection.Conclusion Smo gene may play an important role in the proliferation and apoptosis of esophageal cancer cells. Key words: Esophageal carcinoma; Smo gene; Proliferation; Apoptosis; RNA interference