USP7 and breast cancer: It can be encapsulated into secreted exosomes, thereby promoting BC cell invasion and metastasis via inducing M2‐like macrophages polarisation.Mechanistically, circ‐0100519 acted as a scaffold to enhance the interaction between the deubiquitinating enzyme ubiquitin‐specific protease 7 (USP7) and nuclear factor‐like 2 (NRF2) in macrophages, inducing the USP7‐mediated deubiquitination of NRF2.