Alternative lengthening of telomeres : mechanism and the pathogenesis of cancer

© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ..

Telomere maintenance and elongation allows cells to gain replicative immortality and evade cellular senescence during cancer development. While most cancers use telomerase to maintain telomere lengths, a subset of cancers engage the alternative lengthening of telomeres (ALT) pathway for telomere maintenance. ALT is present in 5%-10% of all cancers, although the prevalence is dramatically higher in certain cancer types, including complex karyotype sarcomas, isocitrate dehydrogenase-mutant astrocytoma (WHO grade II-IV), pancreatic neuroendocrine tumours, neuroblastoma and chromophobe hepatocellular carcinomas. ALT is maintained through a homology-directed DNA repair mechanism. Resembling break-induced replication, this aberrant process results in dramatic cell-to-cell telomere length heterogeneity, widespread chromosomal instability and chronic replication stress. Additionally, ALT-positive cancers frequently harbour inactivating mutations in either chromatin remodelling proteins (ATRX, DAXX and H3F3A) or DNA damage repair factors (SMARCAL1 and SLX4IP). ALT can readily be detected in tissue by assessing the presence of unique molecular characteristics, such as large ultrabright nuclear telomeric foci or partially single-stranded telomeric DNA circles (C-circles). Importantly, ALT has been validated as a robust diagnostic and prognostic biomarker for certain cancer types and may even be exploited as a therapeutic target via small molecular inhibitors and/or synthetic lethality approaches.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:77

Enthalten in:

Journal of clinical pathology - 77(2024), 2 vom: 18. Jan., Seite 82-86

Sprache:

Englisch

Beteiligte Personen:

Mori, Joakin O [VerfasserIn]
Keegan, Joshua [VerfasserIn]
Flynn, Rachel L [VerfasserIn]
Heaphy, Christopher M [VerfasserIn]

Links:

Volltext

Themen:

Biomarkers
Carrier Proteins
DNA Helicases
EC 2.7.7.-
EC 2.7.7.49
EC 3.6.4.-
EC 3.6.4.12
Journal Article
Molecular
Neuroendocrine cells
Pathology
SLX4IP protein, human
SMARCAL1 protein, human
Telomerase
Tumor
X-linked Nuclear Protein

Anmerkungen:

Date Completed 22.01.2024

Date Revised 22.01.2024

published: Electronic

Citation Status MEDLINE

doi:

10.1136/jcp-2023-209005

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM363830502