BRCA1 and breast carcinoma: Use of two short hairpins targeting human LYN (Figure 3E) demonstrated that LYN knockdown in human breast cancer cells also significantly impaired cell growth in the BRCA1-mutated HCC1937 human breast cancer cell line (Figure 3F) and in cells from a BRCA1 mutant breast cancer patient-derived xenograft (PDX) (Figure 3G).