Described is use of a netrin selected among netrin-4, mutated netrin-4, netrin-1, netrin G1 or netrin-3, or one of their fragments or a nucleotide sequence encoding one of the netrins or one of the fragments, or an anti-idiotypic antibody of one of the netrins or of one of the fragments, or of a Fab fragment of the anti-idiotypic antibodies, for preparing a medicine for preventing or treating tumoral or non-tumoral pathologies.