KLK3 and neoplasm: Some of the immediate applications of trimerbodies specific for tumor-associated antigens (e.g. human epidermal growth factor receptor 2, prostate-specific antigen) or targeting tumor stroma (e.g., fibroblast activation protein) and neovasculature (e.g VEGFR-2/KDR or fibronectin extra-domain B) include the development of fusion proteins with angiogenic inhibitors [15], cytokines, enzymes, or truncated receptors, and conjugation with radionuclides [42].