RAD21 and breast cancer: Huang et al. reported that genomic landscape of 312 patients with breast cancer using the FDA-approved Foundation One CDx assay, and the top 5 detected genes in descending order were PIK3CA, TP53, RAD21, NBN, and CCND1 in HR+/HER2− disease subset, TP53, CDK12, PIK3CA, MYC, and RAD21 in HER2+ disease subset, TP53, RAD21, MYC, PIK3CA, and NBN in TNBC disease subset15.