Provided are methods of regulating keratinocytes proliferation and differentiation by subjecting keratinocytes to an agent capable of modulating activity or expression of IGFBP7 thereby regulating keratinocytes proliferation and differentiation. Also provided are methods of treating pathologies characterized by hyperproliferative keratinocytes by administering IGFBP7 polypeptide or a polynucleotide encoding IGFBP7 polypeptide to a subject.