CRISPR Screening Identifies SMARCAL1 and MRN as Modulators of WRN Dependency in MSI-H Colorectal Cancer.

SMARCAL1 and MRN complex are key modulators of WRN dependency in MSI-H colorectal cancer cells, influencing resistance to WRN-targeted therapy.

• Why it matters: Understanding mechanisms of resistance to WRN inhibition is crucial for improving therapeutic strategies in MSI-H colorectal cancer, which relies on WRN to resolve cruciform DNA structures.
• What they did: Researchers performed genome-wide CRISPR/Cas9 screens in colorectal cancer cell lines treated with the WRN inhibitor HRO761, identifying SMARCAL1 and the MRN complex as critical regulators of WRN dependency.
• The result: Depletion of SMARCAL1 or disruption of the MRN complex conferred resistance to WRN inhibition, revealing the SMARCAL1-MRN-ATM axis as a key pathway influencing sensitivity and resistance to WRN-targeted therapies.