TRANSFORMATION BUT NOT RAS-TRANSFECTION INCREASES THE EXPRESSION OF GALECTIN-3 IN HUMAN HOS CELLS

In ras-transfected NIH3T3 cells, the transcription of the Mr 34,000 be ta-galactoside specific lectin galectin-3 depends on transformation ph enotypes. This observation suggests that this lectin is associated wit h the transformation process and/or that the ras oncogene may modulate its expression; nevertheless the involvement of ras-gene product in g alectin-3 gene expression still remains unclear. In the present study, we investigated the galectin-3 expression in human HOS cells transien tly or stably transfected with a ras-containing vector We observed an increase in galectin-3 mRNA and protein content in stably ras-transfec ted cells which had lost their anchorage dependence for growth but no increase in cells which needed anchorage for growth or in transiently ras-transfected cells These results suggest that the galectin-3 up-reg ulation in ras-transfected HOS cells is the consequence of the cell tr ansformation rather than a divert effect of the ras gene product on ga lectin-3 gene expression.