Résumé
Objective To analyze the expression of MIAT in colorectal cancer and explore its molecular mechanism.Methods The expression of MIAT mRNA in colorectal cancer tissues and paracancerous tissues,colorectal cancer cell lines and human normal colorectal mucosa cells was detected by RT-qPCR.HCT-116 cells were transfected with MIAT overexpression vector and infected with knockdown lentivirus,cell proliferation and cell cycle were detected,Western blot was used to analyze the β3-catenin protein levels,luciferase assay was used to detect β-catenin promoter transcription level,C-myc,CCND1,CD44 and Oct3/4 mRNA levels was measured by RT-qPCR.Results The expression of MIAT in colorectal cancer tissues was significantly higher than that in adjacent tissues (t =4.093,P ＜ 0.05).Overexpression of MIAT could promote the proliferation of HCT-116 cells,decrease the rate of G0/G1 phase,activate Wnt/β-catenin pathway and increase its downstream target gene mRNA expression levels (all P ＜ 0.05).Knockdown MIAT shows the inhibition effect.Conclusions MIAT is a tumor-promoting gene of colorectal cancer and may play a role in tumor promotion by activating Wnt/β3-catenin pathway.