CD44 in breast CSCs also played a pivotal role in the regulation of tumour cell proliferation, invasion and migration by modulating the levels of c-Src, a master regulator of the MAPK, PI3K, and STAT3 signalling pathways, via the inhibition of c-Jun and degradation by AKT/GSK-3β signalling [117]. Here, AKT1 is linked to neoplasm.