MIF and cancer: MIF and MIF2 share 34 % sequence identity and have almost identical 3D structures as homotrimers.[5] Moreover, MIF2 interacts with several binding partners of MIF such as CD74 and JAB1, which may suggest MIF2 has functional redundancy to MIF.[6] Our team has shown that MIF2 is involved in lung epithelial cell proliferation and other researchers recognized MIF2 as a potential target for cancer therapeutics.[7] Further investigation of the functions of MIF‐family proteins would benefit from convenient tools to visualize their subcellular localization.