Galectin-1 gene expression and methylation state in human T leukemia cell lines

Galectin-1 has been demonstrated to be a mediator of T-cell apoptosis actin g on activated T-cells and, in a selective manner, on different T leukemia cell lines. Here we show that the sensitivity to galectin-1 is associated w ith repression of the endogenous galectin-1 gene whereas nonsensitive cells express high levels of galectin-1. Repression of galectin-1 gene in sensit ive cells is associated with hypermethylation of the promoter region. Trans ient treatment of nonexpressing cells with the demethylating agent 5-azacyt idine led to irreversible demethylation and subsequent reactivation of gale ctin-1 gene.