The Effect Of MACC1by RNA Interference(RNAi) On The Proliferation And Epithelial-mesenchymal Transition Of Colorectal Cancer Cell

AIM: To investigate the effects of the inhibition of MACC1expression by RNAi onthe proliferation and epithelial-mesenchymal transition(EMT) of SW620．Methods: In this study, the specific MACC1siRNA designed and synthetized inadvance was transfected by lipidosome LipofectamineTM2000into SW620．We alsomade negative control and blank group．The morphology of SW620was observedunder the inverted microscope． MTT was used to analyse the effect on theproliferation after RNAi and to draw the growth curve of each group．In Controlgroup(nontransfection group),Negative control group and MACC1siRNA groupcells,E-cadherin and Vimentin expression were detected by using Western blot. theexpression of E-cadherin and Vimentin were detected by cell immunofluorescence inSW620cells treated with MACC1. Laser scanning confocal microscope is used toidentify the change of cytoskeletal filament which has been colored by phalloidine.Results: The efficiency of cell transfection examined by the inverted fluorescencemicroscope was about70—80％．It can been seen under the inverted microscope thatthe proliferation and the quantity of cells were decreased apparently after thetransfection of MACC1siRNA．MTT shows that RNAi group compared withnegative control group and blank control group were differences between theboth.Western Blot demonstrated that MACC1siRNA group compared with Controlgroup, Vimentin expression decreased significantly（P＜0.05）,E-cadherin expressionincreased significantly（P＜0.05）.Immunofluorescence shows that MACC1siRNAgroup significantly inhibited SW620cells Vimentin decreasing while E-cadherinprotein expression levels was significantly increased. Confocal showed that MACC1induced the number and density of microfilament on cell surface decreased and theskeleton of cells changed. Conclusions: The RNA interference targeted B-catenin can significantly inhibit Theproliferation and epithelial-mesenchymal transition of SW620，and MACC1genemight be a potential target for the molecular therapy of human colorectaladenocarcinoma.