MMP9 and breast cancer: Furthermore, the highly conserved basic helix–loop–helix twist family BHLH transcription factor 1 (TWIST)-dependent increase of integrin β1 expression activated both FAK and integrin-linked kinase (ILK) as well as the MAPK/ERK, PI3K/AKT and wingless-type MMTV integration site family (WNT) signaling cascades, leading to EMT-related phenotype, secretion of MMP9 and MMP2 and the invasive abilities of mammary epithelial cells and breast cancer cells [118].