Expression of galectin-3 in cells exposed to stress -: roles of Jun and NF-κB

Background/Aims: Galectin-3 is an interesting intracellular lectin that appears to be involved in numerous physiological processes. We have analyzed expression of galectin3 in glioblastoma cells exposed to heat-shock, alkylating agents, UV-C radiation and subculturing (trypsinization). Methods: Protein levels of galectin-3 were measured by western-blot analysis using M3/38 monoclonal antibody. The involvement of transcription factors NF-kappa B and Jun in the induction of galectin-3 was addressed using specific inhibitor of NF-kappa B (zL(3)-vs) and antisense-jun oligonucleotides. Results: Exposure of cells to heat-shock or subculturing (trypsinization) decreased levels of galectin-3 to approximately 50%. Alkylating damage and UV-C irradiation caused an increase in the expression of galectin-3. Both inhibition of Jun by antisense-jun oligonucleotides, and inhibition of NF-kappa B by specific proteasomal inhibitor attenuated the induction of galectin-3 by UV-light, but with somewhat different kinetics. Conclusions: We have found that different forms of cellular stress have different effects on the expression of galectin3. Heat-shock and subculturing decrease, while alkylating agents and UV-light increase galectin 3. NF-kappa B and Jun were shown to be involved in the induction of galectin-3 by UV-light, which is a first demonstration that these transcriptional factors are involved in the regulation of galectin3 expression. Copyright (C) 2000 S. Karger AG, Baser.