Objective: To study the DNA methylation status of WT1 gene promoter region in hematologic malignancy cell lines and its correlation with WT1 gene expression.
Methods: 1. RT-PCR and methylation-specific PCR were performed for detecting WT1 gene expression and DNA methylation status in its promoter region in 8226, HL-60, Jurkat, K562, KG-1, NB4, Raji, SHI-1, U266 and U937 cell lines. 2. Treatment of U937 cells with 5-aza-CdR, a demethylation inducing agent and the changes in WT1 gene expression level and its promoter region methylation status were determined.
Results: 1. HL-60, K562, KG-1, NB4 and SHI-1 cells showed higher levels while 8226, Jurkat, Raji, U266 and U937 cells showed extremely low levels of WT1 expression. DNA hypermethylation in WT1 gene promoter region was identified in 8226, Jurkat, Raji, U266 and U937 cells. 2. The WT1 gene expression in U937 was enhanced after treatment with 5-aza-CdR accompanied with the decrease of methylated and the increase of unmethylated levels in its promoter region.
Conclusion: Modulation of the DNA methylation status in WT1 promoter region is one of the epigenetic mechanisms for regulating its expression.