Cyclo(RGDyK) is widely used in biomedical research due to its ability to specifically target integrin receptors, particularly αvβ3 and αvβ5 integrins, which are overexpressed in various cancer cells and endothelial cells of tumor blood vessels. This targeting capability makes it valuable in developing targeted drug delivery systems, where it can be conjugated to nanoparticles, liposomes, or therapeutic agents to enhance their accumulation in tumors while minimizing off-target effects. Additionally, it is employed in imaging applications, such as positron emission tomography (PET) and fluorescence imaging, to visualize tumors and monitor treatment efficacy. Cyclo(RGDyK) also plays a role in studying angiogenesis and metastasis, as it can inhibit integrin-mediated cell adhesion and signaling pathways critical for these processes. Its applications extend to tissue engineering, where it is used to functionalize biomaterials to promote cell attachment and tissue regeneration.