Syk-dependent homologous recombination activation promotes cancer resistance to DNA targeted therapy.
Drug Resist Updat
; 74: 101085, 2024 May.
Article
in En
| MEDLINE
| ID: mdl-38636338
ABSTRACT
Enhanced DNA repair is an important mechanism of inherent and acquired resistance to DNA targeted therapies, including poly ADP ribose polymerase (PARP) inhibition. Spleen associated tyrosine kinase (Syk) is a non-receptor tyrosine kinase acknowledged for its regulatory roles in immune cell function, cell adhesion, and vascular development. This study presents evidence indicating that Syk expression in high-grade serous ovarian cancer and triple-negative breast cancers promotes DNA double-strand break resection, homologous recombination (HR), and subsequent therapeutic resistance. Our investigations reveal that Syk is activated by ATM following DNA damage and is recruited to DNA double-strand breaks by NBS1. Once localized to the break site, Syk phosphorylates CtIP, a pivotal mediator of resection and HR, at Thr-847 to promote repair activity, particularly in Syk-expressing cancer cells. Inhibition of Syk or its genetic deletion impedes CtIP Thr-847 phosphorylation and overcomes the resistant phenotype. Collectively, our findings suggest a model wherein Syk fosters therapeutic resistance by promoting DNA resection and HR through a hitherto uncharacterized ATM-Syk-CtIP pathway. Moreover, Syk emerges as a promising tumor-specific target to sensitize Syk-expressing tumors to PARP inhibitors, radiation and other DNA-targeted therapies.
Key words
Full text:
1
Database:
MEDLINE
Main subject:
Drug Resistance, Neoplasm
/
DNA Breaks, Double-Stranded
/
Homologous Recombination
/
Syk Kinase
Limits:
Animals
/
Female
/
Humans
Language:
En
Journal:
Drug Resist Updat
Journal subject:
ANTINEOPLASICOS
Year:
2024
Type:
Article