ASAP1 and breast cancer: Arf6, which is a small GTPase primarily regulating the recycling of plasma membrane components8, and its downstream effector AMAP1 (also called ASAP1 and DDEF1) are frequently overexpressed in breast cancers, and constitute a signalling pathway that promotes invasion and metastasis of cancer cells by downregulating E-cadherin-based cell–cell adhesion and upregulating recycling of β1 integrins9, 10, 11, 12.