The Dickkopf-related protein 4 (DKK4) is a member of the Dickkopf family, known for modulating Wnt signaling pathways critical in embryonic development, cell proliferation, and cancer. DKK4 acts primarily as a Wnt antagonist by binding to the LRP5/6 co-receptors, inhibiting β-catenin-dependent signaling. However, its role is context-dependent, with studies suggesting dual functions—either suppressing or promoting tumor growth in different cancers. DKK4 antibodies are essential tools for detecting DKK4 expression and studying its biological roles. They are widely used in techniques like immunohistochemistry, Western blotting, and ELISA to analyze tissue-specific distribution, protein levels, and signaling interactions. Research highlights DKK4's overexpression in cancers such as colorectal, breast, and hepatocellular carcinoma, where it may drive tumor progression, metastasis, or drug resistance. Additionally, DKK4 is implicated in developmental disorders and tissue regeneration. Current studies focus on its potential as a therapeutic target or diagnostic biomarker. However, conflicting findings about its pro- or anti-tumor effects underscore the need for further investigation into its regulatory mechanisms. DKK4 antibodies thus serve both research and clinical applications, bridging insights into Wnt-related diseases and therapeutic development.