Cancer Stem Cells and Nanomedicine

blood cells are destined to live a few hours to many weeks, before being seized and destroyed.On one day, therefore, billions of cells must be produced to replace those destroyed.The need for a continuous supply of hematopoietic cells derived from the fact that the blood cells must be replaced continuously during the span of life Recent studies have shown that human stem cells:• located at a frequency of 1: 104 bone marrow cells;• able to regenerate itself thanks to a process of "self-renewal";• metabolically quiescent and rarely comes into the cell cycle;• Helps to expand the pool of "multipotent progenitors" capable of developing all the hematopoietic lineages, eventually losing, at some point, their ability to differentiate into lymphoid sense and become "the commissioned progenitors Myeloid-Erythroid".So that you have a good hematopoiesis requires a hematopoietic microenvironment suitable.So important are the relationships that are established in the marrow from stem cells and osteoclasts, adipocytes, stromal cells, vascular and extracellular matrix system whose function is not only to anchor hematopoietic precursor cells with the right-integrin interaction integrin (VLA-4 and VCAM-1) but also to compartmentalize the soluble factors, such as GM-CSF,