Related Experiment Video
Updated: Aug 6, 2026
08:53
Identifying the Effects of BRCA1 Mutations on Homologous Recombination using Cells that Express Endogenous Wild-type BRCA1
Published on: February 17, 2011
Leveraging Homologous Recombination Deficiency via the Repositioned Prodrug CB1954
James L Elia1, Jarvis Hill2, Collin D Heer3
1Department of Pathology, Yale University, New Haven, CT, USA.
Biorxiv : the Preprint Server for Biology
|July 17, 2026
Summary
CB1954, an old drug, shows high selectivity for BRCA2-deficient tumors by targeting homologous recombination deficiency (HRD). This discovery opens new avenues for precision oncology by repurposing historical DNA-damaging agents.
Area of Science:
- Oncology
- Molecular Biology
- Genetics
Background:
- Homologous recombination deficiency (HRD) is a key cancer vulnerability, but current therapies face limitations.
- Many older DNA-damaging agents lack biomarker-guided application, potentially hiding selective activities.
Purpose of the Study:
- To identify previously unrecognized genotype-selective DNA-damaging agents for cancer therapy.
- To evaluate CB1954, a nitrobenzamide aziridine prodrug, for its efficacy in HRD-positive cancers.
Main Methods:
- Screening of DNA-damaging agents in isogenic HR-proficient and -deficient models.
- Utilizing targeted DNA damage response (DDR) CRISPR screening and isogenic validation.
- Investigating the bioactivation mechanism of CB1954 involving the enzyme NQO2.
Main Results:
- CB1954 demonstrated high selectivity for BRCA2-deficient tumor cells.
- CB1954 selectively induced DNA-damage signaling, apoptosis, and cell death in HR-deficient cells.
- Preclinical studies showed favorable pharmacokinetics and genotype-dependent antitumor activity in BRCA2-deficient xenografts.
Conclusions:
- CB1954 is a potent HRD-selective agent, repositioning it for precision oncology.
- Biomarker-guided profiling of existing DNA-damaging agents can reveal novel therapeutic opportunities for cancers.
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