We found that KLF5, CXCR4 vimentin and N-cadherin were upregulated in circEZH2 group while E-cadherin were downregulated (Fig. 7j), which demonstrated that FUS/circEZH2/KLF5 feedback loop could promoted EMT of BC in CXCR4-induced way thus leading to BCLM (Fig. 8a). Here, KLF5 is linked to breast cancer.