Expression of Phaseolus vulgaris leukoagglutinin-binding oligosaccharides in oral squamous cell carcinoma: Possible association with the metastatic potential

The expression of -GlcNAcβ1-6Man-(β1-6) branched oligosaccharides in carcinoma cells has been considered to influence their metastatic potentials. In the present paper, the lectin histochemistry of oral squamous cell carcinomas obtained in biopsy from 34 patients with Phaseolus vulgaris leukoagglutinin (L-PHA), which potentially binds to N-glycosidic carbohydrates with β1-6 linked lactosamin antennae, was studied in order to analyze the relationship between their staining patterns and metastases. The L-PHA-binding oligosaccharides of the carcinomas were expressed on the cell surface in the following patterns: (i) all cells were positive for the staining ('positive'); (ii) some cells were positive but the rest of the carcinoma cells were negative ('weakly positive'); and (iii) all were negative ('negative'). Statistical analysis revealed that the incidence of the metastasis to regional lymph nodes in the 'positive' cases was significantly higher than that in the 'negative' cases. Moreover, the number of the CD14 positive cells including macrophages in the stroma adjacent to the carcinomas in the 'positive' cases was less than that in the 'negative' or 'weakly positive' cases. The expression of L-PHA-binding oligosaccharides in oral aquamous cell carcinoma may be responsible for their metastatic potential to regional lymph nodes, possibly including their ability to escape macrophage recognition.