The standard-of-care in HR+ breast cancer are targeted therapies, such as ER-targeting (e.g. tamoxifen and fulvestrant), aromatase inhibition, or inhibitors of cyclin-dependent kinases 4/6 (CDK4/6), or a combination of these treatments (4, 5, 6, 7, 8). The gene discussed is CDK4; the disease is breast carcinoma.