| Abstract: | Glycopeptides obtained after pronase digestion of normal rat hepatocytes and Zajdela hepatoma cells after 3H-mannose or 3H-glucosamine incorporation were compared. In both cell types, the glycopeptides were resolved in four peaks after gel filtration on Biogel P6 with a different distribution of radioactivity in normal and tumoral cells. The first peak (I) contained high molecular weight glycopeptides, and particularly a megaloglycopeptide (MW 70,000) exclusively present in malignant cells. Peaks II and III contained only N-linked glycopeptides but the ratio bi-antennary/tri-tetra-antennary glycopeptides was very different in normal and malignant cells. Only polymannosidic oligosaccharides were detected in peak IV and their amount was more important in normal than in malignant cells. These results are discussed in relation with the differentiation state of hepatic cells. |
