This method will serve nicely to become one particular step closer to individualized cancer medi cine and enhanced patient outcome. Adult stem cells are defined as cells which have two cen tral properties. self renewal and differentiation. Many varieties of adult stem cells have the exceptional capability to undergo asymmetric mitotic divisions that generate two distinct daughter cells. Alternatively, they undergo sym metric divisions in a stochastic manner to generate additional stem cells and differentiating cells. One particular daughter primary tains the stem cell properties, when the other differenti ates to replenish specialized cell forms. The capacity of adult stem cell derivatives to divide and differentiate to replace damaged tissues delivers the body with an in ternal repair method. Preceding studies on adult stem cells have focused on understanding how extrinsic signaling pathways regulate suitable stem cell functions.
Furthermore, current evidence shows that intrinsic variables, which include chromatin structure of stem cells, play significant roles in regulating stem cell identity and activity. Epigenetic mechanisms alter the chromatin state of genes without altering their key DNA sequences. Three important epigenetic mechanisms are known to cooperate in stem cells. nucleosome repo sitioning driven by chromatin remodeling factors, selelck kinase inhibitor DNA methylation, and post translational modifications of his tones, including methylation, phosphorylation, acetyl ation, ubiquitination, and sumoylation, Together, these mechanisms may well establish a distinct epigenetic state that results in a special gene expression pattern in stem cells, Perturbations of these epigenetic mecha nisms might bring about premature differentiation or continu ous self renewal proliferation of stem cells, a hallmark of cancer.
The partnership between carcinogenesis and changes in precise gene expression or genome stability has been well documented, Two main epigenetic mecha nisms, DNA methylation and post translational modifi cations of histones, happen to be shown to contribute to the initiation and progression of cancers, Accu mulation of aberrant genetic mutations SB-216763 or abnormal epi genetic profiles could cause tumor initiation in adult stem cell lineages, For example, using the lineage tracing method, studies in mice have shown that aged intestinal stem cells accumulate cancer causing mutations, On the other hand, though most research characterize epigenetic alterations in cancers making use of cancer cell lines or the complete tumor, cells inside a tumor display a wide degree of heterogeneity, and not all of them have the ability to initiate and sustain a tumor, Not too long ago, it has been proposed that a tiny population of cancer cells, termed cancer stem cells, is distinct from other tumor cells and has the capacity to drive tumor initiation and development.