Peptides having pharmacological activity for treating disorders associated with altered cell migration, such as cancer

Peptides and their functionally equiv. derivs. are disclosed, in salified or non-salified form, with the general formula L1-X1-X2-X3-X4, wherein: L1 is H, or acyl, or any natural or non-natural amino acid, optionally N-acylated, N-alkylated and/or Ca-alkylated; X1 and X3, which are equal or different, are any natural or non-natural basic amino acid, optionally N-alkylated and/or Ca-alkylated. X2 is any natural or non-natural amino acid, optionally N-alkylated and/or Ca-alkylated, with the proviso that it is not glycine and amino acids mono-substituted on the a carbon atom with a linear or cyclic alkyl group, from 1 to 10 carbon atoms, and amino acids mono-substituted on the a carbon atom with a linear or cyclic alkyl group containing 4 to 10 carbon atoms, or amino acids mono-substituted on the a carbon atom with an alkyl group containin 1 to 8 carbon atoms, optionally substituted with a carbamoyl, hydroxyl or arom. group; X4 is any natural or non-natural hydrophobic amino acid, optionally Ca-alkylated and/or amidated at the C-terminal end, or any hydrophobic amino alc., or a hydrophobic gem-diamine, optionally N'-alkylated or N'-acylated.