CD44 and breast cancer: It was found to inhibit proliferation and induce apoptosis of CSCs (CD44+CD24Low− and ALDH+) derived from the mammary breast cancer cell line MCF7 (Fiorillo et al., 2016b) and of ALDH+CD133+ cancer stem-like cells from two high-grade serous ovarian cancer patients (Kapur et al., 2022).