RB1 and breast cancer: Arm-length CNAs previously associated with breast cancer (gains in 1q, 3q, 8q, 10p, 12p, 20q; losses in 5q, 8p, 11q, 16q), as well as amplifications/deletions (amplification of ERBB2, ZNF703/FGFR1, CCND1, MYC, EGFR; deletion of RB1, PTEN, CDKN2A/B), were represented within the cohort and recapitulated in the PDXs (Fig. 2b, c, Supplementary Fig. 5a).