Compared to non-TIC/CD44-/CD24+ isolated from both cell lines (that only formed very small MSFs, Supplementary Figure 4A and 4C), TIC/CD44+CD24- MCF7 cells and TIC-like/CD44-/low CD24- T47D cells formed many MSFs (left, Figure 5K, and Supplementary Figure 4B and 4D) that showed larger size (right, Figure 5K, and Supplementary Figure 4B and 4D), supporting our conclusion that IRISOE cells isolated from any breast cancer subtype are indeed TICs. This evidence concerns the gene CD44 and breast cancer.