Cell surface
integrins, especially those binding to
fibronectin (FN), participate in processes of
tumor cell invasion and
metastasis. Changes in glycosylation of cell surface adhesion
proteins are often associated with malignant transformation of cells. In this study we examined the influence of
swainsonine (SW) on adhesion, wound healing and haptotactic migration on FN, comparing the responses of different human
melanoma cell lines: primary WM35 and metastatic WM9, WM239 and A375. We also examined the role of alpha subunits in adhesion to FN. All of the
antibodies inhibited adhesion to FN but with different efficiencies depending on the cell line. Adhesion was mediated mainly by
integrin alpha(5)beta(1) (WM9, A375), alpha(3)beta(1) (WM35, A375, WM239). Scratch
wound repair was significantly faster on FN-coated wells than on
plastic for all cells except for WM9. A375 and WM9 had the greatest migration ability, both expressing the highest level of alpha(5)beta(1)
integrin. It seems very likely that adhesion to FN can be accomplished by many different
integrins, but for effective migration alpha(5)beta(1)
integrin is responsible. Only A375 and WM239 cell lines reacted to SW treatment. In the presence of SW WM239 and A375 cells had 70% and 40% increased adhesion to FN, and their migration was decreased 40% and 50%, respectively. Interestingly, although most of the cell lines share a common profile of
integrins, each line interacted with FN differently. They differed mainly in the repertoire of
integrins used for adhesion, and in the manner in which glycosylation affected these processes. The influence of SW was observed in two metastatic cell lines indicating the contribution of glycosylation status to the progression of
melanoma. The lack of reaction to SW in WM9 cells may suggest that there is a threshold in the expression level of the highly branched N-
glycans that may influence the adhesion and migration properties of the cell.