Telomerasepositive

Telomerasepositive refers to cells that express the enzyme telomerase. Telomerase is a ribonucleoprotein enzyme that adds repetitive DNA sequences to the ends of eukaryotic chromosomes, known as telomeres. In most somatic cells, telomerase activity is low or absent, leading to telomere shortening with each cell division. This shortening acts as a mitotic clock, eventually triggering cellular senescence or apoptosis.

However, in certain cell types, such as germ cells, stem cells, and importantly, the vast majority of cancer cells, telomerase is actively expressed. This active telomerase expression allows these cells to maintain or even lengthen their telomeres, bypassing the normal limitations on cell division. This ability to proliferate indefinitely, often referred to as replicative immortality, is a hallmark of cancer and a crucial factor in tumor development and progression.

The presence of telomerase activity in cancer cells has made it a significant target for cancer therapy. Inhibiting telomerase aims to induce telomere shortening in cancer cells, leading to their senescence or death. While therapeutic strategies targeting telomerase are under investigation, the presence of telomerase in normal stem cells also presents a challenge, as inhibiting it could potentially impair tissue regeneration. Therefore, understanding the precise role and regulation of telomerase in both normal and malignant cells is vital for developing effective and safe treatments.