Vatalanib (PTK787) 2HCl is primarily used in the field of oncology as a potent inhibitor of vascular endothelial growth factor (VEGF) receptor tyrosine kinases. It plays a crucial role in targeting angiogenesis, the process by which new blood vessels form from pre-existing vessels, which is essential for tumor growth and metastasis. By inhibiting VEGF receptors, this compound effectively reduces the blood supply to tumors, thereby limiting their ability to grow and spread. It has been investigated in clinical trials for the treatment of various cancers, including colorectal cancer, renal cell carcinoma, and glioblastoma. Additionally, its application extends to research settings where it is used to study the mechanisms of angiogenesis and the effects of VEGF inhibition in different cancer models. This makes it a valuable tool for both therapeutic development and experimental studies in cancer biology.