The Spindle Assembly Checkpoint Is a Therapeutic Vulnerability of CDK4/6 Inhibitor–Resistant ER⁺ Breast Cancer with Mitotic Aberrations

Investigators developed a panel of CDK4/6i-resistant breast cancer cell lines and patient-derived organoids and demonstrated that a subset of resistant models accumulates mitotic segregation errors and micronuclei, displaying increased sensitivity to inhibitors of mitotic checkpoint regulators TTK and Aurora kinase A/B.