NSC 23766 is primarily used in research settings to study cellular processes, particularly those involving the Rho family of GTPases. It is a selective inhibitor of Rac1, a protein involved in regulating cell motility, adhesion, and proliferation. By inhibiting Rac1, NSC 23766 helps researchers understand its role in cancer metastasis, as Rac1 activation is often linked to tumor invasion and spread. Additionally, it is used to investigate Rac1's involvement in neurological disorders, as abnormal Rac1 signaling is associated with neurodegenerative diseases. NSC 23766 also aids in studying inflammation and immune responses, as Rac1 plays a role in immune cell activation and migration. Its application in these areas provides valuable insights for developing targeted therapies.