Wicha and co-workers have reported that ALDH1+ T-ICs are more frequently detected in receptor-negative basal subtypes of BC cell lines (16 out of 16 cells were positive for ALDH1) than in luminal subtypes (5 out of 12 cells were positive) (Charafe-Jauffret et al, 2009). This evidence concerns the gene ALDH1A1 and breast cancer.