ML251 is primarily used in research settings as a potent and selective inhibitor of the enzyme sphingosine kinase 1 (SphK1). This enzyme plays a crucial role in the sphingolipid metabolism pathway, which is involved in various cellular processes such as cell growth, survival, and inflammation. By inhibiting SphK1, ML251 helps scientists study the effects of disrupting this pathway, particularly in cancer research. It is used to investigate the potential therapeutic benefits of SphK1 inhibition in reducing tumor growth and metastasis. Additionally, ML251 is utilized in studies exploring its role in inflammatory diseases and other conditions where sphingolipid signaling is implicated. Its specificity makes it a valuable tool for understanding the biological functions of SphK1 and developing targeted therapies.