BRCA1 loss-of-function induces high ROS levels in MECs. (A) Brca1 mRNA expression in COMMA-1D cells infected with dox-inducible Brca1 shRNA and treated (+dox) or not (−dox) with dox. (B) Quantitation of ROS in COMMA-1D cells as processed in A. (C) BRCA1 mRNA levels in HMECs infected with Luc shRNA (control) or BRCA1 shRNA. (D) Quantitation of ROS in HMEC as treated in C. (A–D) Data represent the mean ± SEM of three biological replicates. (E) Representative PCR with genomic DNA isolated from B1^+/+, B1^f/+, B1^f/f, and KB1^f/f pMECs using specific primers for detection of Brca1 WT allele, loxP site in intron 3 (F), or cre-mediated deleted allele (Δ). Primers are described in Liu et al. (2007) and Table S1. (F) qPCR with genomic DNA from K, KB1^f/+, and KB1^f/f pMECs using specific primers directed against Brca1 WT allele as reported in Table S1. (G) BRCA1 mRNA levels in K, KB1^f/+, and KB1^f/f pMECs. (H) Representative analysis of BRCA1 protein levels in K and KB1^f/f pMECs. Vinculin was used as a loading control. (I) ROS levels in K, KB1^f/+, and KB1^f/f pMECs. (F, G, and I) Data represent the mean ± SEM of n = 5 mice of each genotype. (J) Representative FACS profile of ROS levels in MaSC/basal and luminal cell subpopulations in B1^f/f and KB1^f/f pMECs stained with DCF-DA. *, P < 0.05; **, P < 0.01.