MS1943 is primarily used in research settings as a potent and selective inhibitor of EZH2, a methyltransferase involved in gene regulation. It is applied in studies focused on understanding the role of EZH2 in cancer development and progression, particularly in cancers where EZH2 is overexpressed or mutated. Researchers utilize this compound to explore potential therapeutic strategies targeting EZH2-dependent pathways, aiming to inhibit tumor growth and improve treatment outcomes. Its application extends to preclinical models to evaluate efficacy and mechanisms of action in various cancer types, including lymphoma and solid tumors.