Biochemical and Biophysical Research Communications, Vol.482, No.4, 802-807, 2017
Anti-apoptotic quinolinate phosphoribosyltransferase (QPRT) is a target gene of Wilms' tumor gene 1 (WT1) protein in leukemic cells
Wilms' tumor gene 1 (WT1) is a zinc finger transcription factor that has been implicated as an oncogene in leukemia and several other malignancies. When investigating possible gene expression network partners of WTI in a large acute myeloid leukemia (AML) patient cohort, one of the genes with the highest correlation to WTI was quinolinate phosphoribosyltransferase (QPRT), a key enzyme in the de novo nicotinamide adenine dinucleotide (NAD+) synthesis pathway. To investigate the possible relationship between WTI and QPRT, we overexpressed WTI in hematopoietic progenitor cells and cell lines, resulting in an increase of QPRT expression. WT1 knock-down gave a corresponding decrease in QPRT gene and protein expression. Chromatin-immunoprecipitation revealed WTI. binding to a conserved site in the first intron of the QPRT gene. Upon overexpression in leukemic 1(562 cells, QPRT conferred partial resistance to the anti-leukemic drug imatinib, indicating possible anti-apoptotic functions, consistent with previous reports on glioma cells. Interestingly, the rescue effect of QPRT overexpression was not correlated to increased NAD + levels, suggesting NAD + independent mechanisms. We conclude that QPRT, encoding a protein with anti-apoptotic properties, is a novel and direct target gene of WTI in leukemic cells. (C) 2016 Elsevier Inc. All rights reserved.