The present invention relates to immunotherapeutic methods, and molecules and cells for use in immunotherapeutic methods. In particular, the present invention relates to the immunotherapy of cancer. The present invention furthermore relates to tumour-associated T-helper cell peptide epitopes, alone or in combination with other tumour-associated peptides, that serve as active pharmaceutical ingredients of vaccine compositions which stimulate anti-tumour immune responses. In particular, the present invention relates to 49 novel peptide sequences derived from HLA class II molecules of human tumour cell lines which can be used in vaccine compositions for eliciting anti-tumour immune responses.