Immunohistochemical analysis of sialic acid and fucose composition in human colorectal adenocarcinoma

The expression of different sialoglycoconjugates and fucoglycoconjugates in normal mucosa and adenocarcinoma samples from 43 colorectal cancer patient s was investigated by using specific lectins and applying a semiquantitativ e analysis. A pronounced decrease in the intracellular binding of the Maack ia amurensis lectin, which recognizes alpha(2,3)-linked sialic acid residue s, was found in the tu moral tissue. In contrast, a significant increase in the staining with the Sambucus nigra lectin (SNA I), which binds to alpha( 2,6)-linked sialic acid residues, was detected in the epithelial cells as w ell as in the mucins from tumors. No significant differences in the reactiv ity with the Aleuria aurantia lectin, which recognizes the sequence Fuc(alp ha 1,G)GlcNAc, between normal and malignant colorectal tissues were detecte d. Furthermore, the correlation between lectin-binding profiles and the pro gnosis of colorectal cancer patients was examined. After an average postope rative follow-up period of 31 months, patients with tumors showing a strong SNA I staining presented a greater probability of disease recurrence. This result suggests that the intensity of staining with SNA I could be a valid parameter for predicting recurrence in colorectal cancer. Copyright (C) 20 00 S. Karger AG, Basel.