MIF and cancer: The protein macrophage migration inhibitory factor (MIF) has been implicated in the pathogenesis of cancers.[2] Overexpression of MIF has been detected in cancer types such as genitourinary cancer,[3] melanoma,[4] neuroblastoma,[5] and lung carcinoma.[6] Remarkably, down‐regulation of MIF expression by gene‐knockout[7] or gene‐knockdown[8, 9] not only reduced tumor progression and metastases, but also induced antitumor immune responses.[10] These results indicate that targeting MIF could be a promising strategy towards development of novel cancer therapeutics.