Regulatory effect of interleukin-4 and interleukin-13 on colon cancer celladhesion

To assess the role of interleukin-4 (IL-4) and interleukin-13 (IL-13) in co lon cancer cell-cell adhesion, we investigated the effect of both cytokines in human colon cancer cell line, colo205 cell-cell adhesion. IL-4 receptor was expressed on the cell surface of colo205, and recombinant IL-4 inhibit ed colo205 cell-cell adhesion in a dose-dependent fashion without inhibitin g cell proliferation. Flow cytometric analysis revealed that monoclonal ant ibodies (mAbs) directed against E-cadherin and carcinoembryonic antigen (CE A) inhibited colo205 cell-cell adhesion and IL-4 significantly inhibited th e expression of E-cadherin and CEA. IL-13 also inhibited colo205 cell-cell adhesion. These results indicated that IL-4 and IL-13 inhibited colon cance r cell-cell adhesion by down-regulation of E-cadherin and CEA molecules. We then investigated the expression of both cytokines from freshly isolated c olon cancer tumour-infiltrating lymphocytes (TILs). With reverse transcript ion-polymerase chain reaction and flow cytometric analysis, we demonstrated that colon TILs expressed IL-4 and IL-13 mRNA and protein. These results s uggest that Th 2 type cytokines IL-4 and IL-13 locally-produced from TILs m ay regulate colon cancer adhesion by down-regulation of adhesion molecules. (C) 2000 Cancer Research Campaign.