PEAK1 and breast cancer: For example, in breast cancer, PEAK1 promotes cell proliferation, epithelial-mesenchymal transition (EMT), aberrant acinar morphology in 3D culture and xenograft growth and metastasis6–8, in non-small cell lung cancer it enhances migration, invasion, EMT and experimental metastasis9, while in pancreatic cancer models it promotes resistance to specific therapies10.