RESUMEN
Electrophoretic analyses of collagenous material have shown that the parietal yolk sac carcinoma (PYSC) ascitic tumour synthesizes polypeptide chains that migrate as type IV procollagen. Having molecular weights of 185,000 and 160,000, these polypeptides are sensitive to collagenase. When the PYSC cells are injected subcutaneously, they form a solid tumour, and type I collagen predominates. The electrophoretic analyses of sulfated glycosaminoglycans and enzymatic degradation have shown a predominance of heparan sulfate in the ascitic tumour, and of chondroitin sulfate B in the solid tumour. Cells cultured from ascitic tumours have maintained the same collagen and sulfated glycosaminoglycan patterns as the original cells, whereas in the solid tumour culture only chondroitin sulfate AC has been detected.