Bone marrow niches in myeloid neoplasms.

Pathological phenotypes of myeloid neoplasms are closely related to genetic/chromosomal abnormalities of neoplastic cells whereas the bone marrow microenvironment, including stromal elements and hematopoietic stem cell niche cells, have a great influence on the differentiation/proliferation of both hematopoietic and neoplastic cells. The pathology of myeloid neoplasms might be generated through the interaction of hematopoietic (stem) cells and stromal cells. The present study aims to provide the morphological/functional aspects of the bone marrow environment in myeloid neoplasms. Among the myeloid neoplasms, myelodysplastic syndromes (MDS) exhibit significant and complex interactions between neoplastic cells and stromal cells. Hematopoietic cells in MDS are greatly influenced by macrophages/niche cells via several signaling pathways. As such, the pathological significance of cell proliferation, cell apoptosis, and anti-apoptosis signals in the bone marrow of myeloid neoplasms, especially MDS bone marrow, will be discussed.