CD44 mediates trastuzumab resistance in HER2-positive breast cancer cells independently of its role as a CSC marker and that this role of CD44 is partly regulated by miRNA.
MKP1 overexpression was also detected in irradiated HER2-positive breast cancer stem-like cells (HER2(+)/CD44(+)/CD24(-/low)) isolated from a radioresistant breast cancer cell population after long-term radiation treatment.