The present invention relates to methods and pharmaceutical compositions for the treatment of cancer. In particular, the present invention relates to a polypeptide comprising or consisting of i) an amino acid sequence ranging from the phenylalanine residue at position 380 to the leucine residue at position 384 in SEQ ID NO: 1 or, ii) an amino acid sequence having at least 70% of identity with the amino acid sequence ranging from the phenylalanine residue at position 380 to the leucine residue at position 384 in SEQ ID NO: 1, or iii) an amino acid sequence which is a retro-inverso of the amino acid sequence ranging from the phenylalanine residue at position 380 to the leucine residue at position 384 in SEQ ID NO: 1 or, iv) an amino acid sequence which is retro-inverso of the amino acid sequence having at least 70% of identity with the amino acid sequence ranging from the phenylalanine residue at position 380 to the leucine residue at position 384 in SEQ ID NO: 1.
