Ki8751 is primarily used in research settings as a selective inhibitor of vascular endothelial growth factor receptor 2 (VEGFR-2), also known as KDR. By blocking this receptor, it interferes with angiogenesis—the formation of new blood vessels—which is a process often hijacked by tumors to support their growth and metastasis. Due to this mechanism, Ki8751 has been investigated for its potential in cancer therapy, particularly in models of solid tumors where angiogenesis plays a critical role. It is commonly applied in preclinical studies to evaluate the effects of VEGFR-2 inhibition on tumor progression, endothelial cell proliferation, and signaling pathways involved in cell survival and migration. Its selectivity makes it a valuable tool for dissecting the role of VEGFR-2 in both physiological and pathological conditions. Additionally, Ki8751 has been used in combination studies with other anticancer agents to assess synergistic effects and improve therapeutic outcomes in experimental oncology.