Role of transforming growth factor-betal-smad signal transduction pathway in patients with hepatocellular carcinoma

摘要

AIM:To explore the role of transforming growth factor-beta1(TGF-β1)-smad signal transduction pathway inpatients with hepatocellular carcinoma.METHODS:Thirty-six hepatocellular carcinoma speci-mens were obtained from Qidong Liver Cancer Instituteand Department of Pathology of the Second AffiliatedHospital of Nanjing Medical University.All primary anti-bodies(polyclonal antibodies)to TGF-β1,type Ⅱ Trans-forming growth factor-beta receptor(TβR-Ⅱ),nuclear fac-tor-kappaB(NF-KB),CD34,smad4 and smad7,secondaryantibodies and immunohistochemical kit were purchasedfrom Zhongshan Biotechnology Limited Company(Bei-jing,China).The expressions of TGF-β1,TβR-Ⅱ,NF-kB,smad4 and smad7 proteins in 36 specimens ofhepatocellular carcinoma(HCC)and its adjacent tissuewere separately detected by immunohistochemistry toobserve the relationship between TGF-β1 and TβR-Ⅱ,between NF-kB and TGF-β1,between smad4 and smad7and between TGF-β1 or TβR-Ⅱ and microvessel density(MVD).MVD was determined by labelling the vesselendothelial cells with CD34.RESULTS:The expression of TGF-β1,smad7 and MVDwas higher in HCC tissue than in adjacent HCC tissue(P<0.01,P<0.05,P<0.01 respectively).The expressionof TβR-Ⅱ and smad4 was lower in HCC tissue than in its adjacent tissue(P<0.01,P<0.05 respectively).Theexpression of TGF-β1 protein and NF-kB protein wasconsistent in HCC tissue.The expression of TGF-β1 andMVD was also consistent in HCC tissue.The expressionof TβR-Ⅱ was negatively correlated with that of MVD inHCC tissue.CONCLUSION:The expressions of TGF-β1,TβR-Ⅱ,NF-kB,smad4 and smad7 in HCC tissue,which are ma-jor up and down stream factors of TGF-β1-smad signaltransduction pathway,are abnormal.These factors areclosely related with MVD and may play an important rolein HCC angiogenesis.The inhibitory action of TGF-β1 isweakened in hepatic carcinoma cells because of abnor-mality of TGF-β1 receptors(such as TβR-Ⅱ)and postre-ceptors(such as smad4 and smad7).NF-kB may causeactivation and production of TGF-β1.