The interaction between Wilms tumor gene 1 (WT1) and the promoter region of the multidrug resistance-1 (MDR1) gene has been previously reported but the clinical significance of the coexpression of WT1 and MDR1 in acute lymphoblastic leukemia (ALL) is still largely unknown.
However, recent reports have clarified that early growth response 1 gene (Egr1) positively regulates MDR1 transcription, while Wilms' tumor suppressor gene (WT1) does negative regulation of MDR1 gene expression in 12-O-tetradecanoylphorbol-13-acetate treated K562 cells.
We demonstrate here that the Wilms' tumor (WT) suppressor, WT1, a member of the EGR family, inhibits the response of the MDR1 promoter to TPA in K562 cells.