细胞衰老及其在抗肿瘤研究中的应用

细胞衰老是细胞脱离细胞周期并不可逆地丧失增殖能力后进入的一种相对稳定的状态,虽然基本代谢过程仍然能够维持,但丧失合成DNA及增殖能力。细胞衰老具有复制衰老、癌基因诱导的衰老及加速衰老等类型。衰老细胞具有细胞体积大而扁平、细胞停止分裂及SA-β-gal反应阳性等明显特性,复制衰老还具有端粒缩短到无法维持染色体结构完整性的特征。目前已知,p53-p21和p16-pRB在细胞衰老过程中起着重要的调控作用,细胞衰老对肿瘤的形成起着天然的屏障作用。通过抑制端粒酶活性来诱导肿瘤细胞衰老和通过胞外刺激或化学治疗药物诱导肿瘤细胞发生衰老样生长停滞,已成为抗肿瘤研究的新思路。

Cell senescence and its critical role in antitumor research

Cellular senescence is an irreversible arrest of cell proliferation and causes the cells to exhaust the potential of division. Senescent cells are metabolically active, but they lack the capacity of DNA synthesis and cell proliferation. In present, three forms of cell senescence have been reported, which is replicative senescence, oncogene-induced senescence and accelerated senescence or premature senescence. The defining characteristics of cellular senescence include increace in cell size, cell flattening, cell cycle arrest and SA-β-gal activity, but for replicative senescence, the shortening of telomeres is characterized. To date, reports revealed that cellular senescence are mainly regulated by p53-p21 and p16-pRB signal pathways. Cellular senescence plays a role of natural barrier in tumor suppression. Inhibit telomerase activity or induction of senescent-like growth arrest has become new targets or strategy for anticancer treatment.