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ABSTRACT: The available evidence suggests that HBV proteins play an important role in the development of hepatocellular carcinoma (HCC). RhoC, a member of the Rho subfamily of the Ras superfamily of homologous genes, had been implicated in tumorigenesis and tumor progression. In a previous study, we demonstrated that HBx and HBs could up-regulate RhoC expression by enhancing its promoter activity. However, the specific mechanisms remain unclear. Here, we demonstrate that overexpression of Ets-1 results in upregulation of RhoC promoter activity and mRNA and protein levels. Expression of transcription factor Ets-1 was significantly higher in HepG2.2.15 cells than that in HepG2 cells. Meanwhile, infection of HepG2 cells with an HBV-adenovirus recombinant virus led to up-regulation of Ets-1. Of the four HBV proteins, HBx and HBs, could increase expression of Ets-1, which consequently contributed to the upregulation of RhoC. These findings might provide a novel insight into HBV-induced HCC metastasis.
Archives of Virology 03/2013; · 2.11 Impact Factor
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ABSTRACT: DnaJ, cooperating with DnaK and GrpE, promotes the folding of unfolded hydrophobic polypeptides, dissociates protein complexes and translocates protein across membranes. Additionally, DnaJ from Streptococcus pneumoniae (SpDnaJ) is involved in the infectious disease process and is being developed as a potential vaccine to prevent bacterial infection. Here the expression, purification, crystallization and preliminary crystallographic analysis of SpDnaJ are reported. The crystals belong to space groups I222 or I212121 and the diffraction resolution is 3.0 Å with unit-cell parameters a = 47.68, b = 104.45, c = 234.57 Å. The crystal most likely contains one molecule in the asymmetric unit, with a VM value of 3.24 Å(3) Da(-1) and a solvent content of 62.1%.
Acta Crystallographica Section F Structural Biology and Crystallization Communications 03/2013; 69(Pt 3):267-9. · 0.51 Impact Factor
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Juan Chen,
Anthony W H Chan,
Ka-Fai To,
Weixian Chen,
Zhenzhen Zhang,
Jihua Ren,
Chunli Song,
Yue-Sun Cheung,
Paul B S Lai,
Suk-Hang Cheng,
Margaret H L Ng, Ailong Huang,
Ben C B Ko
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ABSTRACT: BACKGROUND: The yeast silent information regulator 2 (SIR2) is a histone deacetylase that utilizes NAD(+) as a cofactor for its functions. In mammals, SIR2 is represented by seven homologues (SIRT1-7). Sirtuin 1 (SIRT1), the prototypical member of this family, has been implicated in telomere maintenance and the growth of hepatocellular carcinoma (HCC). Nevertheless, the role of other sirtuins in the pathogenesis of HCC remains elusive. RESULTS: We found that Sirtuin 2 (SIRT2), another member of sirtuin family, also contributes to cell motility and invasiveness of HCC. SIRT2 is up-regulated in HCC cell lines and in a subset of human HCC tissues (23/45). Up-regulations of SIRT2 in primary HCC tumors were significantly correlated with the presence of microscopic vascular invasion (p=0.001), a more advanced tumor stage (p=0.004) and shorter overall survival (p=0.0499). Functional studies by shRNA-mediated suppression of SIRT2 expression in HCC cell lines revealed significant inhibition of motility and invasiveness. Depletion of SIRT2 also led to the regression of epithelial-mesenchymal transition (EMT) phenotypes, whereas the ectopic expression of SIRT2 in the immortalized hepatocyte cell line L02 enhanced the expression of EMT markers, and promoted cell motility and invasiveness. Mechanistic studies revealed that SIRT2 regulates the deacetylation and activation of Akt, which subsequently impinges on the GSK-3β/β-catenin signaling pathway to regulate EMT. Concordantly, we showed that there is a positive correlation between the level of SIRT2 and β-catenin in human HCC. CONCLUSIONS: Our findings have uncovered a novel role of SIRT2 in HCC metastasis, and provide a rationale to explore the use of sirtuin inhibitors in HCC therapy. (HEPATOLOGY 2013.).
Hepatology 01/2013; · 11.66 Impact Factor
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ABSTRACT: The X protein of hepatitis B virus (HBx) is one of the important factors in the development of hepatocellular carcinoma. Raf1 kinase is a central component of many signaling pathways that are involved in normal cell growth and oncogenic transformation. We previously demonstrated that hepatitis B virus regulates Raf1 expression in HepG2.2.15 cells by enhancing its promoter activity and that HBx and HBs might play an important role in this process. However, the underlying molecular mechanisms remain unclear. In this study, we show that nucleotides -209 to -133 of the Raf1 promoter sequence constitute the core region where hepatitis B virus is regulated. This regulation was found to require the involvement of cis-regulatory element AP-2α. We further demonstrated that AP-2α expression was higher in HepG2.2.15 cells (HBV-expressing cells) than in HepG2 cells in vitro. Silencing AP-2α expression by siRNA significantly inhibited the Raf1 promoter activity in HepG2.2.15 cells. These findings indicated that HBV regulates Raf1 promoter activity, possibly through AP-2α.
Archives of Virology 12/2012; · 2.11 Impact Factor
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ABSTRACT: The objective of this study was to screen for antigens of the hepatitis C virus (HCV) to establish a new double antibody sandwich-lateral flow immunoassay (DAS-LFIA) method for testing the presence of anti-HCV antibodies in human serum or plasma. A series of different recombinant HCV proteins in Escherichia coli cells were constructed, expressed, purified and the new DAS-LFIA strip was developed. The sensitivity and specificity of new the DAS-LFIA strip were evaluated by detecting 23 HCV-positive sera, a set of quality control references for anti-HCV detection that contain known amounts of anti-HCV antibodies, and 8 HCV-negative sera. A total of 300 clinical serum samples was examined by both the new DAS-LFIA strip and enzyme-linked immunosorbent assay (ELISA). Data were analyzed using SPSS 11.5 software. The sensitivity and specificity of the new DAS-LFIA strip were 100%. The lowest test line of the HCV DAS-LFIA strips was 2 NCU/ml. Additionally, the concordance between the new DAS-LFIA strip and ELISA methods was 94.33%. In conclusion, our new testing method is rapid, simple, sensitive and specifically detects the presence of anti-HCV antibodies in human serum or plasma. Therefore, it may be used for monitoring HCV.
International Journal of Molecular Medicine 11/2012; 30(5):1041-7. · 1.98 Impact Factor
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ABSTRACT: Many studies showed that RhoC-GTPases are central molecules in oncogenic transformation. The expression of RhoC is significantly increased in hepatocellular carcinoma (HCC). HBV is the major risk factor for HCC. However, it is unknown whether HBV regulating RhoC expression. In this study, we showed the RhoC expression was significantly higher in HepG2.2.15 than that in HepG2 cells. HBV could up-regulate RhoC expression through enhancing the activity of its promoter, and HBs and HBx may involve in this process. After silencing HBs and HBx expressions by using RNA interference, the expression of RhoC in HepG2.2.15 cells could be obviously inhibited. These results would provide useful information for understanding mechanism of HCC induced by HBV infection. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim).
Journal of Basic Microbiology 06/2012; · 1.27 Impact Factor
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ABSTRACT: α(1)-Microglobulin (α(1)m) is one of the phylogenetically most widespread lipocalins and is distributed in various organs and tissues, including liver, heart, eye, kidney, brain, lung, pancreas and skeletal muscle. α(1)m has been found to exert multifarious functions, including interacting with IgA, albumin and prothrombin, binding strongly to haem and exhibiting reductase activity. Nevertheless, little structural information is available regarding these functions of α(1)m. Since determination of three-dimensional structure is a powerful means of functional characterization, X-ray crystallography was used to accomplish this task. Here, the expression, purification, crystallization and preliminary crystallographic analysis of human α(1)m are reported. The crystal belonged to space group P4(3), with unit-cell parameters a = b = 36.45, c = 112.68 Å, and diffracted to a resolution of 2.0 Å. The crystals are most likely to contain one molecule in the asymmetric unit, with a V(M) value of 1.63 Å(3) Da(-1).
Acta Crystallographica Section F Structural Biology and Crystallization Communications 06/2012; 68(Pt 6):692-4. · 0.51 Impact Factor
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ABSTRACT: To develop a Rapid Flow-through assay for distinguishing replicating Tiantan vaccine-generated serological response from true HIV infection.
A Rapid Flow-through Test including gp41, gp36, sk1, sk2 and sk3 antigens was established and the performance of the assay was evaluated in clinical studies and compared with ELISA assay.
Sk1, sk2 and sk3 peptides performed at 100% specificity and slightly but not significantly different sensitivities between ELISA assay (92%, 76% and 41%) and Flow-through Test Kit (92%, 75% and 40%) in diagnosing HIV-1 infections. Of particular importance, Tiantan vaccine recipients that gave false-positive results in gp41 serodetection scored negative for sk1, sk2 and sk3 antibodies.
The Rapid Flow-through Test could be a robust tool in both diagnosing HIV-1/2 infections and differentiating between vaccines induced immunity and immunity resulting from natural exposure, thus serving as potential implementation in HIV vaccine trials.
Clinical biochemistry 05/2012; 45(15):1219-24. · 2.02 Impact Factor
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ABSTRACT: Persistent and recurrent infection of hepatitis B virus (HBV) represents one of the most common and severe viral infections
of humans, and has caused a formidable health problem in the affected countries. Currently used antiviral drugs have a very
limited success on controlling HBV replication and infection. RNA interference (RNAi), a process by which double-stranded
RNA (dsRNA) directs sequence-specific degradation of target mRNA in mammalian and plant cells, has recently been used to knockdown
gene expression in various species. In this study, we sought to determine whether RNAi-mediated silencing of HBV viral gene
expression could lead to the effective inhibition of HBV replication. We first developed RNAi vectors that expressed small
interfering RNA (siRNA) and targeted the HBV core or surface gene sequence. Our results demonstrated that these specific siRNAs
efficiently reduced the levels of corresponding viral RNAs and proteins, and thus suppressed viral replication. Treatment
with siRNA gave the greatest reduction in the levels of HBsAg (92%) and in HBeAg (85%) respectively in the cultured cell medium.
Our findings further demonstrated that the RNAi-mediated antiviral effect was sequence-specific and dose-dependent. Therefore,
our findings strongly suggest that RNAi-mediated silencing of HBV viral genes could effectively inhibit the replication of
HBV, hence RNAi-based strategy should be further explored as a more efficacious antiviral therapy of HBV infection.
Chinese Science Bulletin 04/2012; 49(14):1470-1475. · 1.32 Impact Factor
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ABSTRACT: Drosha regulates the biogenesis of microRNAs (miRNAs) and plays an essential role in the regulation of gene expression. Infection with hepatitis B virus (HBV) causes chronic hepatitis and liver cirrhosis. It is also a major risk factor for hepatocellular carcinoma. Emerging evidence suggests that HBV alters miRNA expression profiles, but the mechanisms underlying this process have not yet been fully elucidated. We therefore examined how HBV affected the production of miRNAs. We found that Drosha mRNA and protein expression were downregulated in cells expressing the HBV genome. This was associated with a reduction in the activity of the Drosha gene promoter. Gene silencing of HBx by RNA interference significantly restored the expression of Drosha. In conclusion, our data show that HBV could downregulate Drosha expression by inhibiting promoter activity, and the transcription factors SP1 and AP-2α may be involved in this process. This provides a new understanding of the mechanism of HBV-induced miRNAs dysregulation.
Antiviral research 04/2012; 94(3):225-31. · 3.61 Impact Factor
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ABSTRACT: PreS1 is a hypothetical candidate domain of L protein for hepatitis B virus (HBV) to adhere to and invade host hepatic cells. This report deals with the expression and purification of recombinant adw2 subtype of the preS1 peptide of hepatitis B virus surface antigen in Escherichia coli. The DNA fragments of the full-length or N/C terminal sequence of preS1 synthesized by PCR were inserted into the prokaryotic expression vector pGST-MOLUC, respectively. Reconstitute plasmids (named pGST-preS1, pGST-preS1N, and pGST-preS1C) were confirmed by sequencing analysis and transferred into Escherichia coli BL21(DE3). Recombinant full-length and N/C terminal of preS1 with GST tag were expressed at high levels in soluble form after induction with IPTG. The recombinant proteins were purified by a single-step affinity chromatography method. The immune reactivity of recombinant preS1 was confirmed by Western blot and virus capture assay. Furthermore, when the purified recombinant protein was used to immunize rabbit, the specific antibody titer can reach 10(-7). Thus, our successful expression system and achievement of purified recombinant preS1 protein and its polyclonal antibody lay the foundation for better understanding of the mechanism of HBV PreS1 protein in virus endocytosis and are helpful in seeking the PreS1-related protein.
Hybridoma (2005) 12/2011; 30(6):525-30. · 0.42 Impact Factor
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ABSTRACT: Both inflammation and cholesterol accumulation play important roles in the development of non-alcoholic fatty liver disease. This study was undertaken to investigate whether inflammation aggravated cholesterol accumulation via disrupting hepatic cholesterol export and we explored the underlying mechanisms.
We used casein injection in C57BL/6J mice, and tumor necrosis factor alpha (TNF-α) stimulation in human hepatoblastoma cell line (HepG2) cells to induce inflammation. Intracellular cholesterol level was examined by Oil Red O staining and quantitative analysis. Bile acid level was quantified by colorimetric analysis. (3)[H] cholesterol assay by scintillation counting was performed to evaluate the cholesterol efflux. The mRNA and protein expression was examined by real-time polymerase chain reaction and Western blot.
Inflammation increased cholesterol accumulation in livers of C57BL/6J mice and in HepG2 cells. High-fat diet in mice and low-density lipoprotein (LDL) loading in HepG2 cells increased bile acid synthesis and cholesterol efflux, enhanced the mRNA and protein expression of liver X receptor α (LXRα), peroxisome proliferator-activated receptors (PPARα, γ), cholesterol 7α-hydroxylase (CYP7A1) and ATP-binding cassette transporter A1 (ABCA1). However, inflammation reduced bile acid synthesis and cholesterol efflux even in high-fat-diet-fed mice and HepG2 cells in the presence of LDL loading. The enhanced effects of these genes and proteins expression due to high-fat diet and LDL loading were inhibited by inflammation both in vivo and in vitro.
Inflammation disrupted PPAR-LXR-CYP7A1/ABCA1-mediated bile acid synthesis and cholesterol efflux resulting in exacerbated cholesterol accumulation in livers of C57BL/6J mice and HepG2 cells.
Journal of Gastroenterology and Hepatology 11/2011; 27(5):974-84. · 2.87 Impact Factor
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ABSTRACT: Immunological detection of viruses and their components using monoclonal antibodies (MAbs) is a powerful diagnostic method. Here we report a detailed method for the establishment of MAbs against severe acute respiratory syndrome coronavirus (SARS-CoV). To express and purify the nucleocapsid protein (N protein) of SARS-CoV and generate MAbs against the N protein, gene encoding N protein was separated into two parts according to the prediction of epitopes and cloned into pET32a(+), respectively. Expression of the target proteins were induced by M isopropyl-β-thio-D-galactopyranoside (IPTG) and purified by a single-step affinity chromatography on a Ni-NTA column. BALB/c mice were immunized with the purified recombinant proteins to prepare MAbs by hybridoma technique. The reactivity and specificity of the MAbs were analyzed by ELISA and Western blot analysis. Seven MAbs against N1 and two MAbs against N2 were obtained. In the present study, recombinant SARS-CoV N protein was expressed and purified and nine specific MAbs against SARS-CoV N protein were obtained successfully. This panel of anti-N MAbs may be used as a tool for rapid and specific diagnosis of SARS-CoV.
Hybridoma (2005) 10/2011; 30(5):481-5. · 0.42 Impact Factor
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ABSTRACT: In order to find microRNA associated with HBV infection and to explore the mechanism of the infection, first of all, we found in our preliminary study that in HepG2 cells transfected with HBV expression plasmid, miR-122 expression was up-regulated, suggesting that miR-122 was related to the HBV infection. On this basis, in the present study, miR-122 and pCH9-HBV1.1 plasmid were cotransfected into HepG2 cells. Southern blot detection result showed that miR-122 can inhibit HBV replication. Using MiRanda computer software, HBx was predicted to be the target sequence of miR-122; Luciferase reporter gene system and Western blot detection of HBx protein expression changes were further used to verify the HBx expression regulated by miR-122. And finally, it can be speculated that miR-122 may affected HBV replication by regulating the expression of HBx.
Sheng wu yi xue gong cheng xue za zhi = Journal of biomedical engineering = Shengwu yixue gongchengxue zazhi 08/2011; 28(4):784-9, 803.
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ABSTRACT: Both lipids and inflammation play important roles in the progression of kidney disease. This study was designed to investigate whether inflammation exacerbates lipid accumulation via LDL receptors (LDLr), thereby causing renal injury in C57BL/6J mice, apolipoprotein E (ApoE) knockout (KO) mice, and ApoE/CD36/scavenger receptor A triple KO mice. The mice were given a subcutaneous casein injection to induce inflammatory stress. After 14 wk, terminal blood samples were taken for renal function, lipid profiles, amyloid A (SAA), and IL-6 assays. Lipid accumulation in kidneys was visualized by oil red O staining. Fibrogenic molecule expression in kidneys was examined. There was a significant increase in serum SAA and IL-6 in the all casein-injected mice compared with respective controls. Casein injection reduced serum total cholesterol, LDL cholesterol, and HDL cholesterol and caused lipid accumulation in kidneys from three types of mice. The expression of LDLr and its regulatory proteins sterol-responsive element-binding protein (SREBP) 2 and SREBP cleavage-activating protein (SCAP) were upregulated in inflamed mice compared with controls. Casein injection induced renal fibrosis accompanied by increased expression of fibrogenic molecules in the triple KO mice. These data imply that inflammation exacerbates lipid accumulation in the kidney by diverting lipid from the plasma to the kidney via the SCAP-SREBP2-LDLr pathway and causing renal injury. Low blood cholesterol levels, resulting from inflammation, may be associated with high risk for chronic renal fibrosis.
AJP Renal Physiology 07/2011; 301(4):F713-22. · 4.42 Impact Factor
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Hua Zhou,
Miao Luo,
Xuefei Cai,
Jian Tang,
Siqiang Niu,
Wenlu Zhang,
Yuan Hu,
Yibing Yin, Ailong Huang,
Dacheng Wang,
Deqiang Wang
Proteins Structure Function and Bioinformatics 07/2011; 79(7):2346-51. · 3.39 Impact Factor
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Mei Mei,
Lei Zhao,
Qing Li,
Yaxi Chen, Ailong Huang,
Zac Varghese,
John F Moorhead,
Suhua Zhang,
Stephen H Powis,
Qifu Li,
Xiong Z Ruan
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ABSTRACT: Chronic systemic inflammation and abnormal free fatty acid metabolism are closely related to ectopic lipid deposition. In this study, we investigate if inflammation tissue-specifically disrupts lipogenesis and lipolysis in nonadipose tissues and adipose tissue, resulting in ectopic lipid deposition in C57BL/6J mice.
We used casein injection in C57BL/6J mice to induce a chronic systemic inflammatory stress in vivo. Serum was analyzed for free fatty acid and cytokines. Insulin sensitivities were evaluated by glucose and insulin tolerance tests. Liver, muscle, adipose tissues were taken for lipid analysis. Real-time polymerase chain reaction and western blotting were used to examine the gene and protein expression of molecules involved in adipogenesis and lipolysis in tissues.
Casein injection elevated serum levels of IL-6 and SAA in mice, which are associated with increased lipid accumulation in liver and muscle, suggesting that chronic systemic inflammation induces ectopic lipid deposition in nonadipose tissues. The inflammatory stress upregulated mRNA and protein expression of sterol regulatory element binding protein 1, fatty acid synthase, and acetyl CoA carboxylase alpha, while inhibited these molecules expression in adipose. Interestingly, in the same experimental setting, inflammation increased triglyceride lipase and hormone-sensitive lipase expression in white adipose tissue. Inflammation also induced insulin resistance and increased serum free fatty acid levels in C57BL/6J mice.
Chronic systemic inflammation increased lipogenesis in nonadipose tissues and lipolysis in white adipose tissue, resulting in ectopic lipid deposition in nonadipose tissues. This disturbed free fatty acid homeostasis and caused insulin resistance in C57BL/6J mice.
Lipids in Health and Disease 06/2011; 10:110. · 2.17 Impact Factor
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ABSTRACT: Cholesterol accumulation plays an important role in the progression of non-alcoholic fatty liver disease. We have demonstrated that inflammation aggravated cholesterol accumulation, causing tissue injury in the vessel and kidney. This study was undertaken to investigate whether inflammatory stress exacerbates hepatic cholesterol accumulation and we explored the underlying mechanisms.
We used casein injection in C57BL/6J mice, interleukin-1β and interleukin-6 stimulation in human hepatoblastoma cell line (HepG2) cells to induce inflammatory stress. Oil Red O staining and intracellular cholesterol assay were used to quantify cellular cholesterol levels. Real-time reverse transcription polymerase chain reaction and Western blot were used to measure messenger RNA (mRNA) and protein expression of target genes. HMGCoA reductase (HMGCoA-r) enzymatic activity and cellular cholesterol synthesis were measured by radioactive methods.
We demonstrated that inflammatory stress increased hepatic cholesterol accumulation and enhanced sterol regulatory element binding protein 2 (SREBP2), low-density lipoprotein receptor (LDLr) and HMGCoA-r mRNA and protein expression in livers of C57BL/6J mice and in HepG2 cells. A high-fat diet in mice or LDL loading in HepG2 cells inhibited mRNA and protein expression of these genes. However, the suppressive effect was overridden by inflammatory stress both in vivo and in vitro. Inflammatory stress increased HMGCoA-r enzymatic activity and cellular cholesterol synthesis in HepG2 cells in the absence or presence of LDL loading.
Inflammatory stress disrupted hepatic SREBP2-mediated low-density lipoprotein receptor and HMGCoA-r feedback regulation resulting in exacerbated cholesterol accumulation in livers of C57BL/6J mice and HepG2 cells.
Journal of Gastroenterology and Hepatology 05/2011; 26(5):875-83. · 2.87 Impact Factor
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Jiao Liu,
Zengchan Wang,
Jia Tang,
Renkuan Tang,
Xiaoliang Shan,
Wenlu Zhang,
Qingmei Chen,
Fan Zhou,
Ke Chen, Ailong Huang,
Ni Tang
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ABSTRACT: The core protein of hepatitis C virus (HCV) has been implicated in HCV-induced liver pathogenesis. Previous data have shown that the HCV core protein has pleiotropic functions, including transcriptional regulation of a number of cellular genes, although the mechanism of gene regulation remains unclear. Wnt/β-catenin signaling is also involved in hepatocellular carcinoma (HCC) tumorigenesis. To elucidate the molecular mechanism of HCV pathogenesis, we examined whether HCV core protein activates Wnt/β-catenin signaling in the hepatoma cell line SMMC-7721. The effects of core protein on Wnt/β-catenin signaling cascades were investigated by luciferase reporter gene assay, immunofluorescence, western blot and RT-PCR analysis. Here, we demonstrate that HCV core protein plays an essential role in activating β-catenin/Tcf-4-dependent transcriptional activity and increases active β-catenin expression and nuclear accumulation in SMMC-7721 cells. An RT-PCR assay indicated that core protein upregulates gene expression of canonical Wnt ligands, such as Wnt2, Wnt3, Wnt3a, Wnt8b, Wnt10a, Wnt10b, frizzled receptors Fzd1, 2, 5, 6, 7, 9, and LRP5/6 co-receptors. However, Wnt antagonists SFRP3, 5 and Dkk1 were moderately repressed. Furthermore, ectopic expression of core protein markedly promoted cell proliferation. The soluble Fzd molecule FrzB or the β-catenin inhibitor siBC efficiently blocked cell growth stimulation by the core gene. Our present findings demonstrate that the HCV core protein activates canonical Wnt signaling through tight regulation of several important molecules upstream of β-catenin and presumably results in promotion of cell proliferation in the SMMC-7721 cell line. Taken together, these data suggested that the core protein may be directly involved in Wnt/β-catenin-mediated liver pathogenesis.
Archives of Virology 02/2011; 156(6):1013-23. · 2.11 Impact Factor
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ABSTRACT: The hepatitis B virus (HBV) protein plays a major role in hepatocellular carcinoma (HCC) development. However, its contribution to tumor invasion and metastasis has not been established so far. HLJ1 was recently cloned and classified as a member of the heat shock protein 40 family (Hsp40/DnaJ) which is abundantly expressed in HBV-related tumors, might be involved in tumor progression. In this study, the role of HBV in activation of HLJ1 was investigated. In HepG2 cells with transit or stable expression of HBV, HLJ1 expression was activated by HBV. The activity assay of HLJ1 promoter revealed that HBV up-regulated HLJ1 expression through the transcription factor YY1 sites within the HLJ1 promoter. YY1 expression was significantly up-regulated by HBV in a concentration-dependent manner. Knockdown of YY1 expression could partially reduce the HBV-induced HLJ1 activation which indicated that YY1 would be involved in HBV-induced HLJ1 expression. In conclusion, our data showed that HBV could promote HLJ1 expression by up-regulating the transcription factor YY1, and this provided a new insight of the mechanism of HBV induction in tumor metastasis.
Virus Research 02/2011; 157(1):76-81. · 2.94 Impact Factor
