Helix pomatia agglutinin lectin-binding oligosaccharides of aggressive breast cancer

Predicting long-term outcome after breast-cancer diagnosis remains problema tic, particularly for patients with clinically small, axillary lymph node- negative tumours, Evidence suggests that the lectin Helix pomatia agglutini n (HPA) identifies oligosaccharides associated with poor-prognosis cancer. Our aim was to identify oligosaccharides that bind HPA in aggressive breast cancers. Breast-cancer cell lines (MCF-7, BT-549 and BT-20) and a cell lin e From human milk (HBL-100), which showed a range of HPA-binding intensitie s, were used to extract HPA-binding glycoproteins, Oligosaccharides were re leased using anhydrous hydrazine and separated on a range of HPLC matrices. We investigated whether HPA-binding oligosaccharides from cell lines were present in human breast-cancer tissues, using 69 breast-cancer specimens fr om patients with between 5 and 10 years' follow-up. A monosialylated oligos accharide was over-expressed in the cell line that bound HPA strongly. Furt her analysis by normal-phase HPLC showed that the 2-aminobenzamide-conjugat ed oligosaccharide had a hydrodynamic volume of 4.58 glucose units (HPAgly 1), Increased expression of HPAgly 1 was associated with HPA staining of br east-cancer specimens (Student's t-test p = 0.025). Analysis of oligosaccha ride levels and disease-free survival after treatment for breast cancer ind icated a shorter disease-free interval for patients with elevated levels of HPAgly 1, This is the first time that histochemical lectin staining has be en correlated with biochemical mapping of oligosaccharides, Using this appr oach, we have identified a monosialylated HPA lectin-binding oligosaccharid e present in breast-cancer cells grown in vitro which is elevated in breast -cancer specimens that bind the lectin, (C) 2001 Wiley-Liss, Inc.