WT1 and GATA1 expression in myelodysplastic syndrome and acute leukemia

The Wilms' tumor protein, WT1, represses transcription from several growth factor genes. WT1 transcription is regulated in erythroid and myeloid linea ges by the transcription factor GATA-1. Using a sensitive, isotopic duplex RT-PCR procedure amplifying WT1 or GATA-1 together with beta-actin as the i nternal control in a single reaction mix, we quantitated the expression of WT1 and GATA-1 mRNA of 16 patients with myelodysplastic syndrome (MDS), 56 with acute myeloid leukemia (AML) and 22 with acute lymphoblastic leukemia (ALL). K562 was used as reference positive control for this cell line expre sses both WT1 and GATA-1. Among MDS patients, increased WT1 expression was found in refractory anemia with excess blast (RAEB) and RAEB in transformat ion (RAEB-T) subtypes compared to the normal controls, whereas WT1 expressi on in refractory anemia (RA) was not different from the normal control leve l. All of AML cases of subtypes M0, M1, M2 and M3 expressed WT1 more than t hree times the normal WT1 level. Subtypes M4 to M7 showed significantly low er WT1 levels than M1 to M3 and AML cases with CD14(+) expressed less WT1 t han CD14(-). Higher than normal WT1 levels were also expressed in cases of ALL.