UNC3866 is primarily utilized in the field of biomedical research, particularly in the study of protein-protein interactions and epigenetic regulation. It functions as a potent and selective antagonist of the Polycomb repressive complex 2 (PRC2), which plays a critical role in gene silencing through histone methylation. By inhibiting PRC2, UNC3866 is employed to investigate the mechanisms of gene expression and cellular differentiation, offering insights into cancer biology and potential therapeutic strategies. Its application extends to the development of targeted therapies for diseases driven by aberrant epigenetic modifications, such as certain types of cancers. Researchers also use UNC3866 to explore its effects on stem cell pluripotency and lineage commitment, contributing to advancements in regenerative medicine.