Lectin-Defined Cell Surface Glycoconjugates of Pancreatic Cancer Cells and Their Nonmalignant Counterparts

Alterations of cell surface carbohydrates of human pancreatic cancer cells from long-term cultures (COLO 357, RPMI 7451, PC 103, PC 107) were assessed ultrastructurally by use of an array of lectin-enzyme conjugates, and compared with lectin-defined changes of glycoconjugates on human pancreatic tissue sections of normal and various pathological conditions. Ulex europeus and, to a lesser degree, Lotus tetragonolobus lectin binding indicate that L-fucose-containing glycoconjugates are expressed predominantly on pancreatic cancer cell surfaces, but not, or restricted to intracytoplasmic structures, on nonmalignant pancreas cells. A comparable binding pattern to pancreatic carcinoma cells is found for Phaseolus vulgaris lectin. This is in contrast to the results with soy bean lectin, the reactivity of which was not restricted to cancer cell surfaces, and with Helix pomatia lectin, which did not bind to pancreatic cancer cells at all, although the latter three lectins possess similar sugar specificities. Between the long-term-cultured malignant pancreas cells differences were observed concerning the binding of wheat germ and pokeweed lectin. Besides, qualitative assets of lectin-binding absorption analyses elaborated quantitative differences in the expression of lectin-defined glycoconjugates on pancreatic cancer cell surfaces.