EPCAM and cancer: The Epi-1 peptide, a nonstandard macrocyclic peptide discovered by a random nonstandard peptides integrated discovery (RaPID) system, has shown a high affinity to the epithelial cell adhesion molecule (EpCAM) that is expressed in several types of tumors and was thus used to construct EpCAM-targeting LNPs for the treatment of EpCAM-positive cancers.