الفهرس 
Stem cell identification
Stem Cell Bioengineering: Culturing andEstablishment of Stem Cell Line (how to maintainstem cells in vitroOnly 14 pages are availabe for public view
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Abstract
Stem cells are cells found in most, if not all, multi-cellular organisms. They are characterized by the ability to renew themselves through mitotic cell division and differentiating into a diverse range of specialized cell types. The two broad types of mammalian stem cells are: embryonic stem cells that are found in blastocysts, and adult stem cells that are found in adult tissues. In a developing embryo, stem cells can differentiate into all of the specialized embryonic tissues. In adult organisms, stem cells and progenitor cells act as a repair system for the body, replenishing specialized cells, but also maintain the normal turnover of regenerative organs, such as blood, skin or intestinal tissues. Cancer stem cells (CSCs) are cancer cells that possess characteristics associated with normal stem cells, specifically the ability to give rise to all cell types found in a particular cancer sample. Recent researches suggests that tumour formation may result from the development of cancer stem cells by the deregulation of normal self-renewal pathways of tissue stem cells .The discovery of cancer stem cells in AML ,breast cancer and some CNS tumours offers an approach to understanding the biology of these conditions. The concept of CSCs may dramatically change the current view for the treatment of cancer because almost all the current treatments target the terminally differentiated cancer cells instead of the cancer-originating stem cells. To improve the outcome of cancer patients, more effective drugs targeting CSCs will be required to eradicate cancer from the origin. More and more data suggest that there are sufficient differences between CSCs and normal stem cells that can be targeted. Agents targeting CSCs specifically may one day be used for the treatment of cancer. CSCs have been identified in a number of malignancies, including both hematological malignancies and solid tumors. This suggests that CSCs are a common phenomenon for cancer. Until recently, anti-cancer therapy has targeted mainly differentiated cancer cells. CSCs are insensitive to these treatments and may result in recurrence. Over the last decade, research on anti-cancer therapy has gradually shifted from traditional non selective cytotoxic chemotherapy to targeted therapy against the underlying pathophysiological changes of cancer. Targeted therapy against CSCs is being explored currently in the laboratory and pursued in clinical trials. We expect that more targeted agents will become available; not only to target cell surface molecules, but also to block the intrinsic signaling pathways of CSCs. Data on clinical trials with some of these targeted agents will soon be available. In the future, cancer treatment will combine targeted therapy against tumor-initiating CSCs with the traditional agents used to eliminate differentiated cancer cells.