Decitabine treatment of cells

To 3x10⁶ REH or NALM-6 cells 5-Aza-2'-deoxycytidine (Decitabine; Sigma-Aldrich) was added to give final concentrations of 50 nM, 150 nM, 350 nM and 500 nM. Water served as the untreated control. After each 48 hour interval the cells were pelleted and resuspended in 3 ml of media and freshly prepared Decitabine. After 7 days, the period required for four doublings for each cell line, pellets prepared from 1.5 ml of each cell suspension were used for RNA and DNA extraction.