Summary: The present invention relates to an isolated peptide to be used in the treatment of cancer consisting of 12 to 50 amino acid residues comprising - at least two beta-strands, or - at least two alpha-helices or - at least one beta-strand and at least one alpha-helix, wherein said beta-strands and/or alpha-helices are separated from each other by at least one turn, wherein the peptide has a positive net charge of +7 or more.
