Preliminary assessment of drug repurposing against virus-associated primary effusion lymphoma

Drug repurposing uses medicine with a given indication to treat a different disease. Primary effusion lymphoma (PEL), a cancer driven by coinfection with the Kaposi sarcoma-associated herpesvirus and the Epstein-Barr virus, lacks an effective treatment. We optimized a rapid, informative, and educational protocol for quantitatively evaluating repurposed small molecules against PEL. The approach tests measurements of PEL cell growth and viability in culture against known inhibitory concentrations. We demonstrate proper quantitative interpretation of the data by using ethacrynic acid, quizartinib, and darapladib as examples. We hope that this practical experimental pipeline will spread awareness of the potential of drug repurposing, especially for diseases like PEL that have unmet clinical needs.