Expression of N-acetyl galactosaminylated and sialylated glycans by metastases arising from primary breast cancer

This study examines the Helix pomatia lectin (HPA) binding characteristics of metastases arising from primary breast cancer, and compares HPA binding patterns with binding of Dolichos biflorus lectin (DBA), Limax flavus lecti n (LFA), and a monoclonal antibody against the Tn epitope. Of 81 blocks of metastases in a range of tissues, taken at autopsy from 46 individuals, 79% were HPA positive. No site specificity with regard to HPA binding was obse rved. Both HPA-positive and -negative tumour deposits were seen within a si ngle individual. HPA-positive tumours were commonly negative for binding of sialic acid specific lectin LFA (86% were negative), Binding patterns of a lpha-GalNAc specific HPA and DBA, and a monoclonal antibody against Tn epit ope (GalNAc-O-Ser/Thr) were markedly different.