ALDH1A1 and neoplasm: A tumor sub-type independent increase in numbers of ALDH1+ cells was observed in BRCA1-mutated cell lines MDA-MB-436 (8.4 ± 0.2 %) and HCC1937 (6.9 ± 0.5 %) when compared to cells possessing a wild type BRCA1 (Fig. 1c).