The study found that midkine (MDK) is not only abnormally highly expressed in various cancers, but as a secreted protein, MDK could activate downstream signaling cascade reactions through interaction with receptors or receptor complexes, and these downstream signaling events may be related to a variety of phenotypic features that lead to cancer development, including cancer cell growth, migration, metastasis, and angiogenesis [27, 28]. The gene discussed is MDK; the disease is cancer.