Title : The important role of hematopoietic stem cell in myelodysplastic syndrome
Abstract:
Hematopoietic stem cells (HSCs) are multi-potent stem cells that defined by their ability to selfrenewal, clifferentiation and maintenance of all blood cell types in the hematological system during the entire lifetime of the organism. In fact, in stem cell niche unit, we have two items as follows: 1) HSC self-renewal and 2) control in balance between s'elf-renewal of HSC, the differentiation and maturation of cells but if the stem cell dysfunction happened such as in myelodysplastic syndrome (MDS), the malignant stem cells can provide a critical reservoir for the malignant progression, namely there is a feed-back mechanism between genetic alterations and the malignant hematopoietic micro-environment in transferring process of information about the result of abnormal actions that the observations endorse on the view of marked malignant stem cells in, during the most of malignant hemptopoietic disorders. For example, the cancer stem cell (CSC)can give rise to the hematopoietic lineage but usually results in a differentiation block leading to the accumulation of immature progenitor/blast cells. So, at the apex of hierarchy are largely quiescent long-lived CSCs with defined self-renewal capacity that sustain the disease and give rise to the rnajority cf the bulk cancer cells which can constitute the disease. Thus, based on some scientific papers, in the statement of leukemia-initiating cells (LICs), the leukemia cases involved with particular genetically defined subsets e.g. specific translocation or point mutation but are much difficult to define for malignant hematopoietic disorders with normal karyotype. In this regard, several experimental mouse models illustrate that micro-environmental changes, either alone or in conjunction rvith corresponding molecular lesions in the hematopoietic compartment, can play a critical role in the malignant disease initiation. Therefore, in the presentation we try to discuss about the important role of HSC as well as the micro-environment contribution to the emergence of the malignant hematopoietic diseases like MDS.
