FOLH1 and neoplasm: This multivalent ligand strategy has been validated for targeting numerous types of tumor cells overexpressing surface biomarkers such as folic acid receptor (FAR) [31,32,33], riboflavin receptor [34,35,36], αvβ3 integrin [37], prostate-specific membrane antigen (PSMA) [38], and epidermal growth factor receptor (EGFR [39]).