[Correlation of stem cell niche to genesis and development of tumor stem cells]

The tumor stem cell model proposes that tumor stem cells are the origin of most tumors. Like normal stem cells, tumor stem cells have the ability to self-renew and to give rise to the variety of proliferating and differentiated cells that make up the bulk of a tumor. Tumor stem cells could be derived from normal stem cells or differentiated cells. The stem cell niches are the microenvironment that maintains stem cells primarily in a quiescent state by providing signals that inhibit cell proliferation and growth. Loss of niches can result in loss of stem cells and increasing niches lead to an increased number of stem cells. Tumor stem cells could live in abnormal niches. Disrupting this abnormal niches may impair tumor stem cell self-renewal, thereby, significantly inhibits the growth of tumors. Targeting the unique microenvironment of tumor stem cells may be the key of effective cancer therapy.