Аннотация:In this chapter we demonstrate that short seven-amino acid residue motifs with high degree of similarity to the sequence LDKYACN (residues 26-32) of human epidermal growth factor (EGF) are characteristic for a number of tumor-associated fetal proteins including alpha-fetoprotein (AFP) and growth factors of EGF family and transforming growth factor (TGF-β) superfamily. Besides, the EGF motifs were found in proteins involved cell adhesion and migration. In multi-modular proteins such motifs are localized within their EGF-like modules. An EGF-like motif LDSYQCT of human AFP (residues 14-20) has been obtained as isolated peptidic fragment using solid phase chemistry and tested for biological activity. Ability of this peptide to regulate cell proliferation and apoptosis has been experimentally demonstrated. Here we suppose that the short EGF-like motifs are responsible for common functions of the proteins and may be considered as a signature of their participation in regulation of embryonic and tumor cell proliferation, differentiation, migration and survival.