Effect of nifedipine in metastatic colon cancer with DNA mismatch repair gene defect

Cancer cells that have DNA mismatch repair deficiency are resistant to many cytotoxic drugs. Calcium channel blockers may inhibit the pathways that cause such resistance. We report a patient with hereditary non-polyposis coli and metastatic colon cancer who had a complete response after treatment with a high dose of nifedipine, a calcium channel blocker. Our findings suggest that drugs that interfere with signal transduction could have a clinical role and deserve further study in selected patients.