Human telomerase holoenzyme (Telomerase) (Telomerase)

The human telomerase holoenzyme is a specialized ribonucleoprotein complex essential for maintaining chromosomal stability by synthesizing telomeric DNA repeats (TTAGGG) at the ends of linear chromosomes (UniProt, 2024). The complex is primarily composed of two core elements: the catalytic protein subunit, human telomerase reverse transcriptase (hTERT), and the non-coding human telomerase RNA (hTR or hTERC), which provides the template for DNA synthesis (NCBI, 2023). In most human somatic cells, telomerase activity is developmentally silenced, leading to progressive telomere shortening and replicative senescence. However, telomerase is reactivated in nearly 90% of human malignancies, granting cancer cells the replicative immortality required for tumor growth and metastasis (PubMed, 2019). This makes the telomerase complex a critical target in oncology, exemplified by the development of imetelstat, a competitive inhibitor that binds the RNA template to block enzymatic activity (FDA, 2024). Beyond direct inhibition, therapeutic strategies also include vaccines targeting hTERT peptides to stimulate an anti-tumor immune response.

Other names

hTERT/hTR complexhTERT/hTERC complexTelomerase reverse transcriptase complexTelomerase ribonucleoprotein complexTERT/TERC complex

Direct competitive inhibition of the telomerase RNA template (hTR) to block telomere elongation; induction of T-cell mediated immune responses against hTERT-derived peptides; small-molecule inhibition of the catalytic reverse transcriptase activity.