The Effect Of RNA Interference Silencing Id-1 Gene On The Proliferation And Apoptosis Of TE-1 In Vitro

Objective:To investigate the effect of si-Id-1 on the proliferation,apoptosis and ERK1/2 pathway of esophageal squamous cell carcinoma cell line TE-1 in vitro,and to study the relationship between signal transduction mechanism of Id-1 and the development of esophageal squamous cell carcinoma.Methods:Si-Id-1 was synthesized and transfected into TE-1 cell by Lipofectamine2000,cell morphological change and the transfection index was observed with inverted fluorescent microscope.The mRNA and protein level of Id-1,ERK1/2 and p-ERK1/2 determined by RT-PCR and Western blot method separately.Cell proliferation was examined by CCK-8 assay at 24h,48h and 72h after transfection.Cell cycle distribution and apoptotic index detected by flow cytometry.Results:Cell morphological change less compared with control groups after transfected under fluorescent microscope.Compared to the control groups,the mRNA level of Id-1 dramatically reduced(P＜0.05),and the mRNA level of ERK1/2 and p-ERKI/2 reduced too(P＜0.05).The protein level of Id-1 and p-ERK1/2 reduced with markedly statistics difference(P＜0.05) compared with control groups,whereas the protein level ERK 1/2 demonstrated no significant difference(P＞0.05).For the TE- 1 cell transfected with si-Id-l,cell proliferation was inhibited significantly compared with control groups(P＜0.01).After transfection of si-Id-1 to TE-1 cell,the percentage of TE-1 in G1-phase was significantly higher than that in control group,the percentage of TE-1 apoptosis cell was significantly higher than that in control group(P＜0.05).Conclusion:The way that transfer Id-1 into the TE-1 cell lines by lipofectamine2000 is safe high-efficiency and low toxicity.SiRNA against Id-1 can effective inactivate the expression of Id-1 in TE-1 cell line.After transfection of si-Id-1 to TE-1 cell,the mRNA level and the protein level of p-ERK1/2 decreased significantly,whereas the protein level ERK1/2 demonstrated no significant difference.The cell proliferation was observed to be slow down;Id-1 is a promising candidate carcinoma-gene and may play a key role in the proliferation.