Isolated IMP-3-derived epitope peptides having Th1 cell inducibility are disclosed herein. In preferred embodiments, such a peptide of the present invention can promiscuously bind to MHC class II molecules and induce IMP-3-specific cytotoxic T lymphocytes (CTLs) in addition to Th1 cells. Such peptides are thus suitable for use in enhancing immune response in a subject, and accordingly find use in cancer immunotherapy, in particular, as cancer vaccines. Also disclosed herein are polynucleotides that encode any of the aforementioned peptides, APCs and Th1 cells induced by such peptides and methods of induction associated therewith. Pharmaceutical compositions that comprise any of the aforementioned components as active ingredients find use in the treatment and/or prevention of cancers or tumors.
