Expression of interferon regulatory factor 1 and 2 in hematopoietic cells of children with juvenile myelomonocytic leukemia

Interferon regulatory factor 1 (IRF-1) is a transcriptional activator in th e interferon system and acts as a tumor suppressor, The structurally relate d IRF-2 represses the effects of IRF-1 by competitive binding to the same D NA sequence elements. Changes in the relative balance between IRF-1 and IRF -2 lead to dysregulation of cell growth and may play a role in the developm ent of neoplasias. The loss of functional IRF-1 has been observed in a numb er of patients with myelodysplastic syndrome (MDS) and leukemia, suggesting a potentially critical role of IRF-1 in leukemogenesis. We studied the exp ression of both transcription factors in peripheral blood (PB) and bone mar row (BM) cells of children with juvenile myelomonocytic leukemia (JMML) usi ng RT-PCR and Southern blot hybridization. No significant difference betwee n the expression levels of IRF-1 and IRF-1 could be detected in PB and BM o f patients with JMML and normal donors. Although our results are preliminar y they suggest that neither the tumor suppressor gene IRF-1 nor the: oncoge ne IRF-2 is involved in the pathogenesis of JMML.