BI-2545 is primarily utilized in biochemical and medical research as a selective inhibitor of BRD4 (bromodomain-containing protein 4). This protein plays a critical role in regulating gene expression and various biological processes, such as cell growth and inflammation. Researchers use it to investigate the effects of BRD4 inhibition on cancer cells, as BRD4 is often dysregulated in various tumors. By blocking BRD4 activity, BI-2545 helps in understanding its role in tumor growth and progression, potentially aiding in the development of targeted cancer therapies. Additionally, it is employed in preclinical studies to evaluate its efficacy in BRD4-related diseases, such as autoimmune disorders and neurological conditions. Further research is needed to confirm its efficacy and safety.