In addition to the EpCAM specific recognition, other approaches based on tissue-specific membrane antigens, such as prostate-specific membrane antigen (PSMA) of prostate cancer and epidermal growth factor receptor 2 (HER2) of breast cancer, have been designed to uniquely separate tissue-specific tumor cells from blood (Santana et al., 2012). Here, FOLH1 is linked to prostate carcinoma.