Conversely, overexpressed Trop2 has been observed in various tumor types, including breast cancer (BC), non-small-cell lung cancer (NSCLC), oral squamous cell carcinoma (OSCC), salivary gland carcinomas (SGC), thyroid cancer (TC), gastric cancer (GC), pancreatic cancer (PC), gallbladder cancer, colorectal cancer (CRC), prostate cancer, ovarian cancer, cervical cancer and urothelial cancer (UC). This evidence concerns the gene TACSTD2 and breast cancer.