These promising results warrant further studies to advance the development of (Rap)2-E1-(Rap)2 or (Rap)2-E1*-(Rap)2, in particular, and other DNL-Rap conjugates, in general, as potential novel therapeutics for triple-negative breast cancer or other Trop-2-expressing cancers. Here, TACSTD2 is linked to triple-negative breast carcinoma.