The possible role and application of WT1 in human leukemia.

WT1, a tumor suppressor gene responsible for the development of childhood kidney tumors, is now also thought to be involved in the occurrence of human leukemia. First, evidence has shown that WT1 functions during hematopoiesis and regulates the proliferation and differentiation of blood cells. Second, specific expression patterns of this gene correlate with the malignant phenotype of leukemia compared with the physiological situation. Third, mutations of WT1 can be detected, though not frequently, in human leukemia but not in normal hematopoietic cells. Thus, a possible role of WT1 in human leukemogenesis has been proposed. Because the expression of this gene is relatively high during the so-called myelodysplastic stages and in all subtypes of human leukemia compared with normal blood cells, the notion has been raised that WT1 can be used as a "panleukemic marker" for the diagnosis of leukemia at the molecular level. The expression level of WT1 may have significance in predicting prognosis and monitoring relapse. Moreover, with a deeper understanding of its role in leukemogenesis, WT1 may serve as a target molecule in the strategy of gene therapy for leukemia.