Correlation of galectin-3/galectin-3-binding sites with low differentiation status in head and neck squamous cell carcinomas

The accurate determination of levels of differentiation is of prognostic va lue in human head and neck squamous cell carcinomas (HNSCCs). Because the d eliberate selection of biochemical determinants accompanying certain stages of differentiation can refine the predictive power of histochemical assess ments, the application of the quantitative evaluation of staining distribut ion and intensity by computer-assisted microscopy is one prerequisite to po tential improvements. We used 2 innovative approaches with peanut agglutini n based on encouraging results with respect to common lectin-histochemistry . First, we used a custom-made neoglycoprotein to monitor the presence of T homsen-Friedenreich (T) antigen-binding sites. Second, we measured the pres ence of 2 galectins immunohistochemically and, at the same time, measured l ectin-histochemically the presence of accessible ligands for the endogenous lectins. We also monitored the presence of calcyclin, a protein with relev ance to cell cycle progression or exocytosis. With 61 cases of HNSCC as the ir basis, including 31 oral, 20 laryngeal, and 10 hypopharyngeal lesions, t he data show that the main modifications observed in connection with a loss of differentiation are related to a modification in the levels of both gal ectin-3/galectin-3-binding site and T-antigen/T-antigen-binding site expres sions. The data obtained also suggest that galectin-3 could act as an accep tor site for the T antigen. Because the level of differentiation is known t o be indicative of the recurrence rate in HNSCCs and our data clearly indic ate that galectin-3 and the T antigen (and their respective binding sites) are involved in dedifferentiation processes, further investigation is warra nted into the roles of galectins in HNSCC tumor progression and recurrence analysis.