Related Experiment Video
Updated: Dec 24, 2025
Covalent Fragment Screening Using the Quantitative Irreversible Tethering Assay
Published on: February 28, 2025
Development of a Model for Chemical Screening Based on Collateral Sensitivity to Target BTK C481S Mutant
Camille Libre1, Ludovic Moro-Sibilot1, Stéphane Giraud2
1Cancer Research Center of Lyon, INSERM U1052 UMR CNRS 5286, Equipe labellisée Ligue Contre le Cancer, Université de Lyon, 69008 Lyon, France.
Abstract:
Targeted therapies have improved the outcome of cancer, but their efficacy is intrinsically limited by the emergence of subclones with a mutation in the gene encoding the target protein. A few examples of collateral sensitivity have demonstrated that the conformational changes induced by these mutations can create unexpected sensitivity to other kinase inhibitors, but whether this concept can be generalized is unknown. Here is described the development of a model to screen a library of kinase inhibitors for collateral sensitivity drugs active on the Bruton Tyrosine Kinase (BTK) protein with the ibrutinib resistance mutation C481S. First, we demonstrate that overexpression of the constitutively active mutant of BTK harboring the E41K mutation in Ba/F3 cells creates an oncogenic addiction to BTK. Then, we have exploited this phenotype to perform a screen of a kinase inhibitor library on cells with or without the ibrutinib resistance mutation. The BTK inhibitors showed the expected sensitivity profile, but none of the drugs tested had a specific activity against the C481S mutant of BTK, suggesting that extending the collateral sensitivity paradigm to all kinases targeted by cancer therapy might not be trivial.
Insights
Cancer therapy resistance can be overcome by collateral sensitivity. This study screened kinase inhibitors for drugs targeting Bruton Tyrosine Kinase (BTK) with a resistance mutation, but found no specific collateral sensitivity drugs.
Area of Science:
- Oncology
- Molecular Biology
- Pharmacology
Background:
- Targeted cancer therapies face resistance due to emerging resistant subclones.
- Collateral sensitivity offers a potential strategy where resistance mutations confer sensitivity to other drugs.
- The generalizability of collateral sensitivity across different kinase inhibitors remains largely unexplored.
Purpose of the Study:
- To develop a model for screening kinase inhibitors for collateral sensitivity against Bruton Tyrosine Kinase (BTK) mutations.
- To investigate collateral sensitivity in BTK inhibitors, specifically addressing the C481S ibrutinib resistance mutation.
- To assess the potential for generalizing the collateral sensitivity paradigm in cancer therapy.
Main Methods:
- Established Ba/F3 cell lines overexpressing constitutively active BTK (E41K) to model oncogenic addiction.
- Screened a kinase inhibitor library against cells with and without the BTK C481S resistance mutation.
- Analyzed drug sensitivity profiles to identify specific activity against the mutant BTK.
Main Results:
- Overexpression of BTK E41K induced oncogenic addiction to BTK in Ba/F3 cells.
- Standard BTK inhibitors exhibited expected sensitivity profiles.
- No tested kinase inhibitors demonstrated specific collateral sensitivity activity against the BTK C481S mutant.
Conclusions:
- The developed model successfully identified oncogenic addiction to BTK.
- The study did not find evidence supporting collateral sensitivity for the BTK C481S resistance mutation with the tested inhibitors.
- Generalizing the collateral sensitivity paradigm to all kinase-targeted cancer therapies may be challenging.
