Cancer metastasis can occur at the very early stage of primary cancer development.[53] In order to study the role of Bmal1−/− CAFs during the early stage of metastasis, we employed a zebrafish metastasis model that allowed us to visualize cancer cell metastasis when the primary tumors were tiny.[37] Relative to controls, co‐implantation of CRC cancer cells plus Bmal1−/− CAFs markedly promoted cancer cell metastasis after 48 h (Figure S8A–F, Supporting Information). This evidence concerns the gene BMAL1 and cancer.