PF-543 hydrochloride is primarily used in biochemical research to study the role of sphingosine kinase 1 (SphK1) in cellular processes. It acts as a potent and selective inhibitor of SphK1, making it valuable for investigating the enzyme's involvement in signaling pathways related to inflammation, cancer, and immune responses. Researchers utilize this compound to explore its potential therapeutic effects in diseases where SphK1 activity is dysregulated, such as certain cancers or inflammatory conditions. Additionally, it helps in understanding the broader implications of sphingolipid metabolism in cellular function and disease progression.