Extensive studies have demonstrated the superior antitumor ability of TROP2-targeted ADCs in the treatment of cancers such as breast cancer, lung cancer, and urothelial cancer, and sacituzumab govitecan has received U.S. Food and Drug Administration approval for the treatment of breast cancer and urothelial cancer [8, 9, 11, 12]. This evidence concerns the gene TACSTD2 and breast cancer.