Association of galectin-1- but not galectin-3-dependent parameters with proliferation activity in human neuroblastomas and small cell lung carcinomas.

Galectins, a family of animal lectins binding beta-galactosides, are involved in growth regulation of diverse cell types in vitro, even harboring the potential to act as biphasic modulators with cell type selectivity. Owing to this capacity they might affect tumor growth when expression is adapted adequately.To determine galectin-1-/-3- related features in routinely-fixed sections of two tumor types with poor prognosis (neuroblastoma and small cell lung carcinoma), immuno- and lectin histochemistry with specific antibodies and labeled galectins was performed.In comparison to previously studied tissue culture models, galectin-3 was frequently present, documenting occurrence of discrepancies between tumor models and clinical material for this protein. Cytoplasmic staining with galectin-1 and its antibody coincides with the proliferative activity of positive tumor cells determined by the MIB-1 monoclonal antibody. No statistical correlation was seen for galectin-3.These results encourage further cell biological studies to assess a regulatory role of galectin-1 on cell growth in vitro as a model for interfering with tumor proliferation by modulating expression of this type of endogenous effector(s).