Transcriptional regulation in myeloid cell differentiation

Myeloid cell differentiation has been investigated on many levels, from the cytokine signals required by each cell lineage to the scheduled expression of distinctive myeloid cell-specific genes and the programmed appearance of characteristic cell surface markers. By analogy to progress in other developmental systems, such as muscle and liver cell differentiation, it should be possible to establish a hierarchy of differentiation signals and transcriptional processes for developing myeloid cells. Current research centers on the cooperation between tissue-specific and more widely expressed transcription factors in the stage-specific regulation of genes essential to myelopoiesis. An attractive emerging concept implicates the programmed regulation of key transcription factors at different stages of development, coordinated by receptor-mediated signals from myeloid colony-stimulating factors. In addition, molecular studies of genes adjacent to the breakpoints of chromosomal translocations in the myeloid leukemias have begun to clarify how aberrantly activated transcription factors can disrupt normal developmental programs and contribute to malignant transformation.