Effects of truncated mutation of adenomatous polyposis coli(APC) on cell-matrix and cell-cell adhesion of MDCK cells

Objective To explore the impact of mutational adenomatous polyposis coli(APC) on cell-matrix,cell-cell adhesion and the relative mechanism.Methods Cell-matrix and cell-cell adhesion assays were employed to determine the adhesion level of two stable cell lines MDCK-N2-APC and MDCK-GFP.The truncated APC of N2 fragment,which spans residues 449-781,was studied in comparison with control cells including GFP alone.Immunofluorescence staining,RT-PCR analysis and Western blot were applied to check several adhesion molecules which are key roles in cell contact process.Results In contract with control,cell-matrix adhesion was averagely increased to 180% in N2 cells,whereas cell-cell adhesion was reduced by about 30%.Our experiments accordingly indicated that CD29 expression level was enhanced and the expression level of E-cadherin was enervated in N2 cells.And these two molecules all have crucial roles in cell-matrix and cell-cell adhesion.Conclusions Full length APC plays a crucial role in cell-matrix and cell-cell adhesion.Truncated N2-APC may influence cell adhesion through changing the expression level of certain adhesion molecules,such as E-cadherin and CD29.The truncation mutation of APC fragment N2 restrained in the colon cancer cells will alter the cell invasion and migration by affecting cell adhesion and cell-matrix adhesion.