DM4-SMCC is primarily used in the development of antibody-drug conjugates (ADCs) for targeted cancer therapy. It serves as a linker-payload molecule, where DM4 is a potent cytotoxic agent derived from maytansine, and SMCC is a crosslinker that facilitates the attachment of DM4 to monoclonal antibodies. This combination allows for the precise delivery of the cytotoxic payload to cancer cells, minimizing damage to healthy tissues. The application of DM4-SMCC is particularly significant in treating various cancers, including breast cancer, lymphoma, and leukemia, by enhancing the efficacy and specificity of therapeutic antibodies. Its role in ADCs has contributed to advancements in personalized medicine and improved treatment outcomes for cancer patients.