Quantification of methylation degrees and expression of the inhibitor genes in CLL cell lines EHEB and MEC-1 upon treatment with 5-aza-dC. (A) The average percentage of methylation was recorded by bisulphite pyrosequencing after 72 h growth in pure medium (deep blue bars) and in presence of 1.0 or 2.0 μM 5-aza-dC (intermediate and light blue bars), respectively. (B) Quantification of mRNA expression levels by PCR. As in panel A, control and experimental conditions are represented by different shades of red. Three separate measurements were performed for each sample. GAPDH was used as an internal control. The expression in untreated cells was set to 1. Significant induction of mRNA expression in both or one cell line is indicated with ** or * at the bottom.