Altered glycosylation of membrane glycoproteins associated with human mammary carcinoma

N-Linked sugar chains of normal mammary gland, mammary carcinomas (primary lesion), and axillary lymph node metastases of mammary carcinomas were released from their membrane preparations by hydrazinolysis and their structures were analyzed. Fractionation using a Datura stramonium agglutinin (DSA)-Sepharose column revealed that the metastasized carcinomas contain more than twice as much DSA-binding oligosaccharides as the normal gland, and the primary carcinomas contain an intermediate amount. These oligosaccharides were elucidated to have tri- and tetraantennary structures containing the GlcNAc beta 1-->6(GlcNAc beta 1-->2)Man group with and without N-acetyllactosamine repeating units. Lectin blot analysis of membrane glycoproteins and histochemical staining of tissues using biotinylated DSA indicated that these glycosylation changes predominantly occur in a limited number of glycoproteins with apparent molecular weights of 90, 160, and 210 kilodaltons, and mammary carcinomas are distinguishable from normal gland by their intense intracytoplasmic staining.