POTENTIAL USEFULNESS OF BIOTINYLATED NEOGLYCOPROTEINS AS TUMOR-MARKERS

We used several biotinylated neoglycoproteins as tumor markers to dete ct and localize endogenous carbohydrate-binding proteins in cultured h epatoblastoma, melanoma, and bladder carcinoma tumor cells. The neogly coproteins used consisted of cellobiose, fucose, N-acetyl-gatactosamin e, N-acetyl-glucosamine, lactose, maltose, mannose, melibiose, and xyl ose. In addition, naturally occurring asialofetuin that was chemically disialylated was also used. Binding to the cultured tumor cells was m ade visible with the avidin-peroxidase technique. Depending on the typ e of neoglycoprotein used, markedly different expression of cytoplasmi c and nuclear receptors for sugars (endogenous lectins) was obtained f rom rat hepatoblastoma, human melanoma, and bladder carcinoma tumor ce lls. The most pronounced staining differences were documented for asia lofetuin and the neoglycoproteins containing fucose, N-acetyl-galactos amine, and lactose.