ERBB2 and breast cancer: In addition to the antibody, a partner of IR700 for a conjugate of PIT that has been reported so far includes an affibody (a small protein mimetic [6–7 kDa]) for HER2-overexpressing breast cancer [92], an LMW ligand composed of Glu-Urea-Lys for prostate cancer with prostate-specific membrane antigen [98], and a lection for CEA-expressing pancreatic cancer [99,100].