The present invention provides a compound represented by the formula (1): wherein X a and Y a are each a single bond or the like, cancer antigen peptide A is an MHC class I-restricted cancer antigen peptide, and R 1 is a hydrogen atom； a group represented by the formula (2) : wherein X b and Y b are each a single bond or the like, and cancer antigen peptide B is different from the cancer antigen peptide A and is an MHC class I or II-restricted cancer antigen peptide； a group represented by the formula (3): wherein X c and Y c are each a single bond or the like, and cancer antigen peptide C is an MHC class II-restricted cancer antigen peptide； or cancer antigen peptide D, wherein the cancer antigen peptide D is an MHC class I or II-restricted cancer antigen peptide containing one cysteine residue, or a salt thereof, for example.
