Expression Of β-catenin And Dickkopf1in Psoriasis Epidermis

Backgroud：Psoriasis is an agnogenic,commom chronic,inflammatoryskin disorder,characterized by abnormal keratinocyte proliferation anddifferentiation.There is evidence that adherens junction systems of keratinocytesare abnomal.β-catenin is a component of intercellular adherens junctions and also is atranscription factor as a part of the Wnt signaling pathway.β-catenin has afunction of regulating the proliferation and differentiation of keratinocyte stemcells.Dickkopf1(DKK1)acts as a negative regulator to block the Wnt signalingpathway and inhibits transctiption of β-catenin.Also,DKK1can regulate thedifferentiation of mesenchymal stem cells.We assume that β-catenin and DKK1may play roles in proliferation and differentiation of psoriasis.Objective： To investigate the expressions of β-catenin and DKK1inpsoriasis vurlgris,erythrodermic psoriasis,pustular psoriasis,arthropathicpsoriasis and the active stage,resting stage,paracmasis of psoriasis vulgaris.Toevaluate their functions in psoriasis. Methord： The expression of β-catenin and DKK1in63cases of psoriasisand20cases of normal epidermis were detected by immunohistochemistry.Result：In normal skin, positive staining for β-catenin was detected in alllayers of the epidermis at the sites of cell membranes(100%). While abnormalexpression of β-catenin was detected in psoriatic epidermis(58.73%).There wasdifference between psoriatic epidermis and normal epidermis(P<0.01).Nostaning for β-catenin was deceted in cytoplasms and nucleolus in psoriaticepidermis and normal epidermis.In normal skin,. positive staining for DKK1was detected in all layers ofthe epidermis at the sites of cytoplasms(100%). Downregulation of DKK1expression was detected in psoriatic epidermis (69.84%). There was differencebetween psoriatic epidermis and normal epidermis (P<0.05).Conclusion： β-catenin and DKK1may play roles in pathogenesis ofvulgaris.Loss of DKK1activiates Wnt/β-catenin signal pathway. β-cateninaccumulates in the cytosol and can translocate into the nucleus, where itinteracts with members of the Tcf Lef class of DNA binding proteins andtranscriptions factors. As a result, β-catenin regulates proliferation anddifferentiation of psoriatic keratinocytes.