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[Effects of Fuzheng Huayu Capsule on the ratio of TGF-beta1/BMP-7 of chronic viral hepatitis B fibrosis patients of Gan-Shen insufficiency blood-stasis obstruction syndrome]. Tang Cui-Lan,Zhou Zhou,Shi Wei-Qun Zhongguo Zhong xi yi jie he za zhi Zhongguo Zhongxiyi jiehe zazhi = Chinese journal of integrated traditional and Western medicine OBJECTIVE:To observe the effects of Fuzheng Huayu Capsule (FHC) on the liver function, HBV DNA quantization, the ratio of transforming growth factor-beta1/bone morphogenetic protein-7 (TGF-beta1/ BMP-7) of peripheral blood mononuclear cells (PBMCs), HBV DNA YMDD variation, and the liver tissue pathology of chronic viral hepatitis B fibrosis patients of Gan-Shen insufficiency blood-stasis obstruction syndrome (GSIBSOS) on the basis of antiviral treatment by lamivudine. METHODS:Eighty chronic viral hepatitis B fibrosis patients of GSBSOS were randomly assigned to two groups. Patients in the control group (43 cases) were treated with lamivudine alone, while those in the treatment group (37 cases) were treated with lamivudine + FHC. The treatment period lasted for 6 months. By the end of treatment lamivudine was continually given to all patients, and patients were followed up for 6 months. Before and after treatment, liver tissue pathology was examined by liver biopsy. The serum HBV DNA quantization, the ratio of TGF-beta1/BMP-7 were determined by fluorescence quantitative polymerase chain reaction (PCR). HBV DNA YMDD variation was tested by the end of follow-ups. RESULTS:Better effects were obtained in decreasing the levels of ALT, AST, and HBV DNA after 6 months of treatment in the two groups, with statistical difference when compared with before treatment in the same group, but with no statistical difference between the two groups. At the end of the 6th month follow-up, YMDD variation occurred in 9 cases of the control group and in 5 cases of the treatment group, with statistical difference between the two groups (P < 0.05). FHC could significantly reduce the ratio of TGF-beta1/BMP-7, significantly lower in the treatment group (0.09 vs 0.25, P < 0.05). In the aspect of liver tissue pathological changes, the rates of inflammatory activity over G3 and fibrosis degree S3 in the treatment group were significantly lower than those in the control group (P < 0.05). CONCLUSIONS:On the basis antiviral treatment of lamivudine for chronic viral hepatitis B fibrosis patients of BSOS, additional application of FHC could lower the HBV DNA YMDD variation, improve the hepatic inflammation and fibrosis, and exert anti-fibrosis by decreasing the ratio of TGF-beta1/BMP-7.
The hepatitis B virus encoded oncoprotein pX amplifies TGF-beta family signaling through direct interaction with Smad4: potential mechanism of hepatitis B virus-induced liver fibrosis. Lee D K,Park S H,Yi Y,Choi S G,Lee C,Parks W T,Cho H,de Caestecker M P,Shaul Y,Roberts A B,Kim S J Genes & development Hepatitis B, one of the most common infectious diseases in the world, is closely associated with acute and chronic hepatitis, cirrhosis, and hepatocellular carcinoma. Many clinical investigations have revealed that hepatic fibrosis is an important component of these liver diseases caused by chronic hepatitis B. TGF-beta signaling plays an important role in the pathogenesis of fibrosis in chronic hepatitis and cirrhosis. As these diseases are associated with hepatitis B virus (HBV) infection, we examined the possibility that the HBV-encoded pX oncoprotein regulates TGF-beta signaling. We show that pX enhances transcriptional activity in response to TGF-beta, BMP-2, and activin by stabilizing the complex of Smad4 with components of the basic transcriptional machinery. Additionally, confocal microscopic studies suggest that pX facilitates and potentiates the nuclear translocation of Smads, further enhancing TGF-beta signaling. Our studies suggest a new paradigm for amplification of Smad-mediated signaling by an oncoprotein and suggest that enhanced Smad-mediated signaling may contribute to HBV-associated liver fibrosis. 10.1101/gad.856201
Reversible phospho-Smad3 signalling between tumour suppression and fibrocarcinogenesis in chronic hepatitis B infection. Deng Y-R,Yoshida K,Jin Q L,Murata M,Yamaguchi T,Tsuneyama K,Moritoki Y,Niu J Q,Matsuzaki K,Lian Z-X Clinical and experimental immunology Transforming growth factor (TGF)-β, type I receptor (TβRI) and c-Jun N-terminal kinases (JNK) phosphorylate Smad3 differentially to create 2 isoforms phosphorylated (p) at the COOH-terminus (C) or at the linker region (L) and regulate hepatocytic fibrocarcinogenesis. This study aimed to compare the differences between how hepatitis B virus (HBV) infection affected hepatocytic Smad3 phosphorylated isoforms before and after anti-viral therapy. To clarify the relationship between Smad3 phosphorylation and liver disease progression, we studied 10 random patients in each stage of HBV-related fibrotic liver disease (F1-4) and also 10 patients with HBV-associated HCC. To examine changes in phosphorylated Smad3 signalling before and after anti-HBV therapies, we chose 27 patients with chronic hepatitis B who underwent baseline and follow-up biopsies at 52 weeks from the start of nucleoside analogue treatments (Lamivudine 100 mg daily or Telbivudine 600 mg daily). Fibrosis stage, inflammatory activity and phosphorylated Smad3 positivity in the paired biopsy samples were compared. Hepatocytic pSmad3C signalling shifted to fibrocarcinogenic pSmad3L signalling as the livers progressed from chronic hepatitis B infection to HCC. After nucleoside analogue treatment, serum alanine aminotransferase (ALT) and HBV-DNA levels in 27 patients with HBV-related chronic liver diseases were decreased dramatically. Decrease in HBV-DNA restored pSmad3C signalling in hepatocytes, while eliminating prior fibrocarcinogenic pSmad3L signalling. Oral nucleoside analogue therapies can suppress fibrosis and reduce HCC incidence by successfully reversing phosphorylated Smad3 signalling; even liver disease progressed to cirrhosis in chronic hepatitis B patients. 10.1111/cei.12259
Activation of TGF-β1-CD147 positive feedback loop in hepatic stellate cells promotes liver fibrosis. Li Hai-Yan,Ju Di,Zhang Da-Wei,Li Hao,Kong Ling-Min,Guo Yanhai,Li Can,Wang Xi-Long,Chen Zhi-Nan,Bian Huijie Scientific reports Activation of hepatic stellate cells (HSCs) by transforming growth factor-β1 (TGF-β1) initiates HBV-associated fibrogenesis. The mechanism of TGF-β1 modulating HSC activation is not fully uncovered. We hypothesized a positive feedback signaling loop of TGF-β1-CD147 promoting liver fibrogenesis by activation of HSCs. Human HSC cell line LX-2 and spontaneous liver fibrosis model derived from HBV transgenic mice were used to evaluate the activation of molecules in the signaling loop. Wound healing and cell contraction assay were performed to detect the CD147-overexpressed HSC migration and contraction. The transcriptional regulation of CD147 by TGF-β1/Smad4 was determined using dual-luciferase reporter assay and chromatin immunoprecipitation. We found that a positive reciprocal regulation between TGF-β1 and CD147 mediated HSC activation. CD147 over-expression promoted HSC migration and accelerated TGF-β1-induced cell contraction. Phosphorylation of Smad2 and Smad3 in cooperation with Smad4 mediated the TGF-β1-regulated CD147 expression. Smad4 activated the transcription by direct interaction with CD147 promoter. Meanwhile, CD147 modulated the activated phenotype of HSCs through the ERK1/2 and Sp1 which up-regulated α-SMA, collagen I, and TGF-β1 synthesis. These findings indicate that TGF-β1-CD147 loop plays a key role in regulating the HSC activation and combination of TGF-β receptor inhibitor and anti-CD147 antibody might be promised to reverse fibrogenesis. 10.1038/srep16552
TGF-β signaling is activated in patients with chronic HBV infection and repressed by SMAD7 overexpression after successful antiviral treatment. Argentou Nikoletta,Germanidis Georgios,Hytiroglou Prodromos,Apostolou Eirini,Vassiliadis Themistoklis,Patsiaoura Kalliopi,Sideras Paschalis,Germenis Anastasios E,Speletas Matthaios Inflammation research : official journal of the European Histamine Research Society ... [et al.] OBJECTIVES:Although animal studies demonstrated that Smad7 induction ameliorates TGF-β/SMAD-mediated fibrogenesis, its role in human hepatic diseases is rather obscure. Our study explored the activation status of TGF-β/activin pathway in patients with chronic liver diseases, and how it is affected by successful antiviral treatment in chronic HBV hepatitis (CHB). METHODS:Thirty-seven CHB patients (19 with active disease, 14 completely remitted on long-term antiviral treatment and 4 with relapse after treatment withdrawal), 18 patients with chronic HCV hepatitis, 12 with non-alcoholic fatty liver disease (NAFLD), and 3 controls were enrolled in the study. Liver mRNA levels of CTGF, all TGF-β/activin isoforms, their receptors and intracellular mediators (SMADs) were evaluated using qRT-PCR and were correlated with the grade of liver inflammation and fibrosis staging. The expression and localization of pSMAD2 and pSMAD3 were assessed by immunohistochemistry. RESULTS:TGF-β signalling is activated in CHB patients with active disease, while SMAD7 is up-regulated during the resolution of inflammation after successful treatment. SMAD7 overexpression was also observed in NAFLD patients exhibiting no or minimal fibrosis, despite the activation of TGF-β/activin signaling. CONCLUSIONS:SMAD7 overexpression might represent a mechanism limiting TGF-β-mediated fibrogenesis in human hepatic diseases; therefore, SMAD7 induction likely represents a candidate for novel therapeutic approaches. 10.1007/s00011-016-0921-6
The hepatitis B virus X protein induces paracrine activation of human hepatic stellate cells. Martín-Vílchez Samuel,Sanz-Cameno Paloma,Rodríguez-Muñoz Yolanda,Majano Pedro L,Molina-Jiménez Francisca,López-Cabrera Manuel,Moreno-Otero Ricardo,Lara-Pezzi Enrique Hepatology (Baltimore, Md.) UNLABELLED:Chronic hepatitis B virus (HBV) infection is a major cause of liver fibrosis, eventually leading to cirrhosis and hepatocellular carcinoma. Although the involvement of the X protein of HBV (HBx) in viral replication and tumor development has been extensively studied, little is known about its possible role in the development of fibrosis. In this work we show that expression of HBx in hepatocytes results in paracrine activation and proliferation of hepatic stellate cells (HSCs), the main producers of extracellular matrix proteins in the fibrotic liver. Both human primary HSCs and rat HSCs exposed to conditioned medium from HBx-expressing hepatocytes showed increased expression of collagen I, connective tissue growth factor, alpha smooth muscle actin, matrix metalloproteinase-2, and transforming growth factor-beta (TGF-beta), together with an enhanced proliferation rate. We found that HBx induced TGF-beta secretion in hepatocytes and that the activation of HSCs by conditioned medium from HBx-expressing hepatocytes was prevented by a neutralizing anti-TGF-beta antibody, indicating the involvement of this profibrotic factor in the process. CONCLUSION:Our results propose a direct role for HBx in the development of liver fibrosis by the paracrine activation of stellate cells and reinforce the indication of antiviral treatment in patients with advanced HBV-related chronic liver disease and persistent liver replication. 10.1002/hep.22265
Regulation of transforming growth factor-beta 1 expression by the hepatitis B virus (HBV) X transactivator. Role in HBV pathogenesis. Yoo Y D,Ueda H,Park K,Flanders K C,Lee Y I,Jay G,Kim S J The Journal of clinical investigation TGF-beta 1 has been implicated in the pathogenesis of liver disease. The high frequency of detection of the hepatitis B virus X (HBx) antigen in liver cells from patients with chronic hepatitis, cirrhosis, and liver cancer suggested that expression of HBx and TGF-beta 1 may be associated. To test this possibility, we examined the expression of TGF-beta 1 in the liver of transgenic mice expressing the HBx gene. We show that the patterns of expression of TGF-beta 1 and Hbx protein are similar in these mice and that HBx activates transcription of the TGF-beta 1 gene in transfected hepatoma cells. The cis-acting element within the TGF-beta 1 gene that is responsive to regulation by Hbx is the binding site for the Egr family of transcription factors. We further show that the Egr-1 protein associates with the HBx protein, allowing HBx to participate in the transcriptional regulation of immediate-early genes. Our results suggest that expression of Hbx might induce expression of TGF-beta 1 in the early stages of infection and raise the possibility that TGF-beta 1 may play a role in hepatitis B virus pathogenesis. 10.1172/JCI118427
The etiology of liver damage imparts cytokines transforming growth factor beta1 or interleukin-13 as driving forces in fibrogenesis. Weng Hong-Lei,Liu Yan,Chen Jia-Lin,Huang Tong,Xu Li-Jun,Godoy Patricio,Hu Jun-Hua,Zhou Cheng,Stickel Felix,Marx Alexander,Bohle Rainer M,Zimmer Vincent,Lammert Frank,Mueller Sebastian,Gigou Michelle,Samuel Didier,Mertens Peter R,Singer Manfred V,Seitz Helmut K,Dooley Steven Hepatology (Baltimore, Md.) UNLABELLED:It is unknown whether transforming growth factor beta1 (TGF-beta1) signaling uniformly participates in fibrogenic chronic liver diseases, irrespective of the underlying origin, or if other cytokines such as interleukin (IL)-13 share in fibrogenesis (e.g., due to regulatory effects on type I pro-collagen expression). TGF-beta1 signaling events were scored in 396 liver tissue samples from patients with diverse chronic liver diseases, including hepatitis B virus (HBV), hepatitis C virus (HCV), Schistosoma japonicum infection, and steatosis/steatohepatitis. Phospho-Smad2 staining correlated significantly with fibrotic stage in patients with HBV infection (n = 112, P < 0.001) and steatosis/steatohepatitis (n = 120, P < 0.01), but not in patients with HCV infection (n = 77, P > 0.05). In tissue with HBx protein expression, phospho-Smad2 was detectable, suggesting a functional link between viral protein expression and TGF-beta1 signaling. For IL-13, immunostaining correlated with fibrotic stage in patients with HCV infection and steatosis/steatohepatitis. IL-13 protein was more abundant in liver tissue lysates from three HCV patients compared with controls, as were IL-13 serum levels in 68 patients with chronic HCV infection compared with 20 healthy volunteers (72.87 +/- 26.38 versus 45.41 +/- 3.73, P < 0.001). Immunohistochemistry results suggest that IL-13-mediated liver fibrogenesis may take place in the absence of phospho-signal transducer and activator of transcription protein 6 signaling. In a subgroup of patients with advanced liver fibrosis (stage > or =3), neither TGF-beta nor IL-13 signaling was detectable. CONCLUSION:Depending on the cause of liver damage, a predominance of TGF-beta or IL-13 signaling is found. TGF-beta1 predominance is detected in HBV-related liver fibrogenesis and IL-13 predominance in chronic HCV infection. In some instances, the underlying fibrogenic mediator remains enigmatic. 10.1002/hep.22934
Hepatitis B virus X protein promotes proliferation and upregulates TGF-beta1 and CTGF in human hepatic stellate cell line, LX-2. Guo Guang-Hui,Tan De-Ming,Zhu Ping-An,Liu Fei Hepatobiliary & pancreatic diseases international : HBPD INT BACKGROUND:Chronic hepatitis B virus (HBV) infection is a major cause of liver fibrosis, but the mechanisms underlying HBV-related fibrogenesis are still unknown. Although the roles of HBV X protein (HBx) remain poorly understood, it is thought to play an important role in the regulation of cellular growth and hepatocarcinogenesis. The aim of this study was to determine the role of HBx in liver fibrogenesis by studying the effect of HBx on the proliferation and expression of fibrosis-related molecules in the human hepatic stellate cell line, LX-2. METHODS:We established an in vitro co-culture system with LX-2 cells and a stable QSG7701-HBx cell line which had been transfected with the HBx gene. 3H-TdR incorporation and flow cytometry were used to determine the effects of HBx on the proliferation of LX-2 cells. Alpha-smooth muscle actin (alpha-SMA), transforming growth factor-beta1 (TGF-beta1), transforming growth factor-beta receptor II (TGF-betaRII), and connective tissue growth factor (CTGF) in LX-2 cells were analyzed by Western blotting. In addition, the expression levels of collagen type I (ColI) from the co-cultured media were measured by ELISA. RESULTS:3H-TdR incorporation increased significantly in LX-2 cells co-cultured with QSG7701-HBx cells compared to those cultured with QSG7701-pcDNA3 and QSG7701 (non-tumorigenic human liver cell line). Cell cycle results revealed that HBx accelerated the progression of G1 to S in LX-2 cells. The expressions of alpha-SMA, TGF-beta1, TGF-betaRII, CTGF and ColI were significantly increased in the co-cultures of LX-2 cells with stable QSG7701-HBx cells. CONCLUSION:These results suggest that HBx may facilitate liver fibrosis by promoting hepatic stellate cell proliferation and upregulating the expression of fibrosis-related molecules.
Hepatitis B virus X antigen promotes transforming growth factor-beta1 (TGF-beta1) activity by up-regulation of TGF-beta1 and down-regulation of alpha2-macroglobulin. Pan Jingbo,Clayton Marcy,Feitelson Mark A The Journal of general virology Hepatitis B virus (HBV) X antigen (HBxAg) may contribute to the development of hepatocellular carcinoma (HCC) by activation of signalling pathways such as NF-kappaB. To identify NF-kappaB target genes differentially expressed in HBxAg-positive compared to -negative cells, HepG2 cells consistently expressing HBxAg (HepG2X cells) were stably transfected with pZeoSV2 or pZeoSV2-IkappaBalpha. mRNA from each culture was isolated and compared by PCR select cDNA subtraction. The results showed lower levels of alpha(2)-macroglobulin (alpha(2)-M) in HepG2X-pZeoSV2 compared to HepG2X-pZeoSV2-IkappaBalpha cells. This was confirmed by Northern and Western blotting, and by measurement of extracellular alpha(2)-M levels. Elevated transforming growth factor-beta1 (TGF-beta1) levels were also seen in HepG2X compared to control cells. Serum-free conditioned medium (SFCM) from HepG2X cells suppressed DNA synthesis in a TGF-beta-sensitive cell line, Mv1Lu. The latter was reversed when the SFCM was pretreated with exogenous, activated alpha(2)-M or with anti-TGF-beta. Since elevated TGF-beta1 promotes the development of many tumour types, these observations suggest that the HBxAg-mediated alteration in TGF-beta1 and alpha(2)-M production may contribute importantly to the pathogenesis of HCC. 10.1099/vir.0.19650-0
Important roles played by TGF-β in hepatitis B infection. Karimi-Googheri Masoud,Daneshvar Hamid,Nosratabadi Reza,Zare-Bidaki Mohammad,Hassanshahi Gholamhossein,Ebrahim Maryam,Arababadi Mohammad Kazemi,Kennedy Derek Journal of medical virology Hepatitis B virus (HBV) which includes, fulminant, acute, chronic, asymptomatic, and occult HBV infection is the most prevalent virus that leads to human liver diseases. Chronic, asymptomatic, and occult infection can induce further sever diseases such as hepatocellular carcinoma (HCC) and cirrhosis of the liver. The underlying mechanisms that allow progression of the prolonged forms of the infection and subsequent HCC or cirrhosis of the liver are yet to be clarified. However, many researchers have suggested that immunological and genetic parameters may play important roles in the etiology of hepatitis B. Transforming growth factor beta (TGF-β) is an important cytokine with dual regulatory functions in the immune system and in the responses against viral infections. However, the pathways and mechanisms controlling these are not fully understood. The crucial roles of TGF-β in the development of Th17 and T regulatory lymphocytes, the main cell types involved in autoimmunity and destructive immune related diseases, have been documented and this provides insights into TGF-β function during hepatitis infection and subsequent HCC and cirrhosis of the liver. Recent findings also confirm that TGF-β directly alters hepatocyte function during hepatitis B, hence, the aim of this review is to address the current data regarding the association and status of TGF-β with hepatitis B infection and its related disorders including HCC and cirrhosis of the liver. 10.1002/jmv.23727
TGF-β-miR-34a-CCL22 signaling-induced Treg cell recruitment promotes venous metastases of HBV-positive hepatocellular carcinoma. Yang Pengyuan,Li Qi-Jing,Feng Yuxiong,Zhang Yun,Markowitz Geoffrey J,Ning Shanglei,Deng Yuezhen,Zhao Jiangsha,Jiang Shan,Yuan Yunfei,Wang Hong-Yang,Cheng Shu-Qun,Xie Dong,Wang Xiao-Fan Cancer cell Portal vein tumor thrombus (PVTT) is strongly correlated to a poor prognosis for patients with hepatocellular carcinoma (HCC). In this study, we uncovered a causative link between hepatitis B virus (HBV) infection and development of PVTT. Mechanistically, elevated TGF-β activity, associated with the persistent presence of HBV in the liver tissue, suppresses the expression of microRNA-34a, leading to enhanced production of chemokine CCL22, which recruits regulatory T (Treg) cells to facilitate immune escape. These findings strongly suggest that HBV infection and activity of the TGF-β-miR-34a-CCL22 axis serve as potent etiological factors to predispose HCC patients for the development of PVTT, possibly through the creation of an immune-subversive microenvironment to favor colonization of disseminated HCC cells in the portal venous system. 10.1016/j.ccr.2012.07.023
TGF-β and iron differently alter HBV replication in human hepatocytes through TGF-β/BMP signaling and cellular microRNA expression. Park Sun O,Kumar Mukesh,Gupta Sanjeev PloS one The nature of host-virus interactions in hepatitis B virus infection is incompletely understood. Since soluble factors, e.g., cytokines and metals, may exacerbate liver injury in chronic hepatitis, we considered that defining the effects of receptor-mediated signaling upon viral replication will be significant. Consequently, we studied effects of iron or TGF-β-induced TGF-β/BMP signaling in the HepG2 2.2.15 cell model of hepatitis B virus replication. We found iron and TGF-β increased hepcidin mRNA expression or TGF-β receptor kinase activity, respectively, which indicated that 2.2.15 cells responded appropriately to these substances. However, iron increased but TGF-β decreased hepatitis B virus mRNA and DNA expression. TGF-β induced expression at the mRNA level of multiple TGF-β/BMP pathway genes. This change was not observed in iron-treated cells. On the other hand, presence of SMAD proteins in iron or TGF-β-treated cells, including of SMAD4, did confirm convergence of TGF-β/BMP signaling pathways under these conditions. Since transcription factors in TGF-β/BMP signaling pathways could not have directly targeted hepatitis B virus itself, we studied whether iron or TGF-β exerted their effects through alternative mechanisms, such as by involvement of antiviral cellular microRNAs. We discovered cellular microRNA expression profiles were significantly different in iron or TGF-β-treated cells compared with untreated control cells. In many cases, exposure to iron or TGF-β changed microRNA expression in opposite directions. Introduction in cells of sequences representing such differentially expressed microRNAs, e.g., hsa-miR-125a-5p and -151-5p, even reproduced effects on virus replication of iron- or TGF-β. We surmised that TGF-β/BMP pathway members, i.e., SMADs, likely governed iron or TGF-β-induced microRNA expression. Iron may have mediated Drosha/DGCR8/heme-mediated processing of microRNAs. In turn, cellular microRNAs regulated replication of hepatitis B virus in iron or TGF-β-treated cells. This knowledge should advance studies of mechanisms in viral-host interactions, hepatic injury, and therapeutic developments for hepatitis B. 10.1371/journal.pone.0039276
Hepatitis B virus X protein shifts human hepatic transforming growth factor (TGF)-beta signaling from tumor suppression to oncogenesis in early chronic hepatitis B. Murata Miki,Matsuzaki Koichi,Yoshida Katsunori,Sekimoto Go,Tahashi Yoshiya,Mori Shigeo,Uemura Yoshiko,Sakaida Noriko,Fujisawa Junichi,Seki Toshihito,Kobayashi Kazuki,Yokote Koutaro,Koike Kazuhiko,Okazaki Kazuichi Hepatology (Baltimore, Md.) UNLABELLED:Hepatitis B virus X (HBx) protein is suspected to participate in oncogenesis during chronic hepatitis B progression. Transforming growth factor beta (TGF-beta) signaling involves both tumor suppression and oncogenesis. TGF-beta activates TGF-beta type I receptor (TbetaRI) and c-Jun N-terminal kinase (JNK), which differentially phosphorylate the mediator Smad3 to become C-terminally phosphorylated Smad3 (pSmad3C) and linker-phosphorylated Smad3 (pSmad3L). Reversible shifting of Smad3-mediated signaling between tumor suppression and oncogenesis in HBx-expressing hepatocytes indicated that TbetaRI-dependent pSmad3C transmitted a tumor-suppressive TGF-beta signal, while JNK-dependent pSmad3L promoted cell growth. We used immunostaining, immunoblotting, and in vitro kinase assay to compare pSmad3L- and pSmad3C-mediated signaling in biopsy specimens representing chronic hepatitis, cirrhosis, or hepatocellular carcinoma (HCC) from 90 patients chronically infected with hepatitis B virus (HBV) with signaling in liver specimens from HBx transgenic mice. In proportion to plasma HBV DNA levels, early chronic hepatitis B specimens showed prominence of pSmad3L in hepatocytic nuclei. HBx-activated JNK/pSmad3L/c-Myc oncogenic pathway was enhanced, while the TbetaRI/pSmad3C/p21(WAF1) tumor-suppressive pathway was impaired as human and mouse HBx-associated hepatocarcinogenesis progressed. Of 28 patients with chronic hepatitis B who showed strong oncogenic pSmad3L signaling, six developed HCC within 12 years; only one of 32 patients showing little pSmad3L developed HCC. In contrast, seven of 30 patients with little Smad3C phosphorylation developed HCC, while no patient who retained hepatocytic tumor-suppressive pSmad3C developed HCC within 12 years. CONCLUSION:HBx shifts hepatocytic TGF-beta signaling from the tumor-suppressive pSmad3C pathway to the oncogenic pSmad3L pathway in early carcinogenic process. Hepatocytic pSmad3L and pSmad3C assessment in HBV-infected liver specimens should prove clinically useful for predicting risk of HCC. 10.1002/hep.22765
Parenchymal transforming growth factor beta-1: its type II receptor and Smad signaling pathway correlate with inflammation and fibrosis in chronic liver disease of viral etiology. Calabrese Fiorella,Valente Marialuisa,Giacometti Cinzia,Pettenazzo Elena,Benvegnu Luisa,Alberti Alfredo,Gatta Angelo,Pontisso Patrizia Journal of gastroenterology and hepatology BACKGROUND AND AIMS:Transforming growth factor-beta (TGF-beta) system is involved in the control of cell growth and extracellular matrix formation. Previous studies in patients with chronic liver disease have shown that increased TGF-beta expression significantly correlates with the degree of hepatic fibrosis. The aim of our study was to define TGF-beta system expression in hepatic parenchymal cells and its significance in patients with differing extents of chronic liver disease of viral etiology. METHODS:Expression of TGF-beta 1, TGF-beta 1 type II receptor (TGF-beta RII) and the Smad signaling pathway was evaluated in consecutive liver sections of 77 patients with chronic liver disease (65 HCV positive and 12 HBV positive). Results were correlated with histological scores and apoptotic activity. RESULTS:TGF-beta 1 was demonstrated in the liver of 30/56 (53.6%) patients with chronic hepatitis and 20/21 (95%) patients with cirrhosis, but in none of the 20 normal livers. Positive cytokine reaction was seen both in stromal cells and hepatocytes. Expression of TGF-beta RII and Smad proteins showed a distribution pattern similar to that of TGF-beta, with a direct correlation in terms of immunoreactivity extent. A significant correlation was found between parenchymal expression of TGF-beta system and inflammatory and fibrosis scores. No correlation was found with apoptotic index and other morphological, clinical or virological parameters. CONCLUSIONS:The TGF-beta system is up-regulated at the ligand, receptor and signaling level in the liver of patients with more active disease. The strong expression of TGF-beta and the Smad pathway in parenchymal cells suggests that hepatocytes, in addition to mesenchymal cells, may play an important role in the progression of liver disease.