HMFe@BS is camouflaged with MΦM (MΦM@HMFe@BS) to evade macrophage-phagocytosis, increase blood circulation time, and accumulate within the breast cancer through the interaction between α4-integrin in MΦM and breast cancer overexpressed vascular cell-adhesion molecule (VCAM)-1. Here, VCAM1 is linked to breast cancer.