Telomere Dynamics and Aging (original) (raw)

“…Telomerase is an enzyme that is mainly expressed in stem cells and cancer cells, and it can compensate for telomere shortening during DNA replication and keep the telomere length. In physiological conditions, most somatic cells suffer from gradually shortening of telomere by 15-50 bp each year due to the lack of telomerase activity [30,31]. However, abnormal alteration of telomere length can cause chromosome instability and result in subsequent carcinogenesis.…”

Section: Discussionmentioning

“…Telomerase is an enzyme that is mainly expressed in stem cells and cancer cells, and it can compensate for telomere shortening during DNA replication and keep the telomere length. In physiological conditions, most somatic cells suffer from gradually shortening of telomere by 15-50 bp each year due to the lack of telomerase activity [30,31]. However, abnormal alteration of telomere length can cause chromosome instability and result in subsequent carcinogenesis.…”

Section: Discussionmentioning

“…Although telomerase is active in every cell division of single-celled organisms, multicellular animals including humans largely silence telomerase after early embryogenesis, with complete repression or only tightly regulated transient expression in human somatic cells (2,3). This repression of telomerase contributes to tumor suppression by limiting the proliferative capacity of any individual cell lineage.…”

Section: Introductionmentioning

“…Telomerase is active in early human embryo cells but is repressed upon tissue differentiation (2). Without telomerase activity, human somatic cells count down cell divisions toward a proliferative limit due to progressive telomere shortening (3). To bypass this growth barrier, the majority of human cancers reactivate telomerase and balance the telomere attrition coupled to genome replication with new telomeric repeat synthesis (4).…”

mentioning