Derventzi A, Rattan S I, Gonos E S
National Hellenic Research Foundation, Institute of Biological Research and Biotechnology, Athens, Greece.
Anticancer Res. 1996 Sep-Oct;16(5A):2901-10.
Normal diploid cells cultivated in vitro exhibit limited division potential while undergoing ageing during serial passaging. In contrast, cells that have been genetically transformed appear to have lost the regulatory mechanisms of limited growth potential and may continue to divide indefinitely. While cellular mortality is characterised by a progressive cessation of cell growth manifested in cell culture by senescence, immortalisation is the escape from senescence as a result of multiple mechanisms involving the inactivation of tumour suppressor genes, the elevated expression of oncogenes, as well as other genetic and epigenetic changes. The mechanisms governing mortality and immortality are fundamentally linked. The physiological and biochemical features which characterise cellular mortality are examined, herein in the search for markers and timing mechanisms of mortality. The genetic elements involved in the control of mortality and immortality are also discussed, and the fundamental similarities between the molecular and genetic aspects which govern the determination of the phenotypes manifesting the two processes are underlined.
体外培养的正常二倍体细胞在连续传代过程中经历老化时，其分裂潜能有限。相比之下，经过基因转化的细胞似乎失去了有限生长潜能的调节机制，可能会无限期地继续分裂。细胞死亡的特征是细胞生长逐渐停止，在细胞培养中表现为衰老，而永生化则是由于多种机制导致的从衰老中逃脱，这些机制包括肿瘤抑制基因的失活、癌基因表达的升高以及其他遗传和表观遗传变化。控制细胞死亡和永生化的机制在根本上是相互关联的。本文研究了表征细胞死亡的生理和生化特征，以寻找死亡的标志物和时间机制。还讨论了参与控制细胞死亡和永生化的遗传因素，并强调了控制这两个过程所表现出的表型的分子和遗传方面的基本相似性。
