Liver Tissues Of Chronic Hepatitis Research Articles

Identifying of HBV DNA in liver tissues of chronic hepatitis and hepatocellular carcinoma to study the Hepatitis B virus silent infection in Egyptian patients

Hepatitis B virus (HBV) infection comprises one of the most frequent causes of adult morbidity and mortality in Egypt. The presence of HBV genomes in the absence of HBV surface antigen (HBsAg) individuals is referred to as occult HBV infection. This study aimed to detect HBV integration in HBsAg negative chronic hepatitis and hepatocellular carcinoma (HCC) cases by extraction of DNA from tissue and serum of chronic hepatitis and HCC cases to find out the silent HBV infection. Subjects and Methods: Seventy-three patients divided into three groups; group I: included fifty-two sera samples for hepatocellular carcinoma (HCC) patients with negative HBsAg and positive HBcAb; of which fourteen liver tissues samples were taken (group I). Nine chronic hepatitis patients with negative HBsAg and positive HBcAb (group II) were studied in both liver tissue and serum sample. Twelve chronic hepatitis patients with positive HBsAg and positive HBcAb were included as a control group. DNA from those groups has been separated from tissue sections that have been mounted on glass slides. Results: The present study showed that 1/52 (1.9%) of the patients with HCC were positive for HBV DNA in the serum while all the 52 HCC patients were negative for HBV DNA in the liver tissue. Conclusion: The present showed that 1/52 (1.9%) of the patients with HCC were positive for HBV DNA in the serum. The explanation for this is the low endemicity of HBV infection in Egypt which differ HBV DNA detection process.

The USP18 cysteine protease promotes HBV production independent of its protease activity

BackgroundHepatitis B virus (HBV) infection remains as one of the major public health problems in the world. Type I interferon (IFN) plays an essential role in antiviral defense by induced expression of a few hundred interferon stimulated genes (ISGs), including ubiquitin-specific protease 18 (USP18). The expression level of USP18 was elevated in the pretreatment liver tissues of chronic hepatitis B(CHB) patients who did not respond to IFN treatment. Thus, this study was designed to investigate the effects of USP18 on HBV replication/production.MethodsThe levels of wild type USP18(WT-USP18) and USP18 catalytically inactive form C64S were up-regulated by plasmids transfection in HepAD38 cells, respectively. Real-time PCR and ELISA were used to quantify HBV replication. Type I IFN signaling pathway was monitored at three levels: p-STAT1 (western Blot), interferon stimulated response element (ISRE) activity (dual luciferase assay) and ISGs expression (real time PCR).ResultsOur data demonstrated that overexpression of either WT-USP18 or USP18-C64S inactive mutant increased the intracellular viral pgRNA, total DNA, cccDNA, as well as HBV DNA levels in the culture supernatant, while silencing USP18 led to opposite effect on HBV production. In addition, upregulated WT-USP18 or USP18-C64S suppressed ISRE activity and the expression levels of p-STAT1 and ISGs.ConclusionUSP18 promoted HBV replication via inhibiting type I IFN signaling pathway, which was independent of its protease activity.

Gene expression profiling of hepatocarcinogenesis in a mouse model of chronic hepatitis B

BackgroundHepatocellular carcinoma (HCC) is a common complication of chronic viral hepatitis. In support of this notion, we have reported that hepatitis B surface antigen (HBsAg)-specific CD8+ T lymphocytes critically contribute to inducing chronic liver cell injury that exerts high carcinogenic potential in a hepatitis B virus (HBV) transgenic mouse model. The dynamics of the molecular signatures responsible for hepatocellular carcinogenesis are not fully understood. The current study was designed to determine the serial changes in gene expression profiles in a model of chronic immune-mediated hepatitis.MethodsThree-month-old HBV transgenic mice were immunologically reconstituted with bone marrow cells and splenocytes from syngeneic nontransgenic donors. Liver tissues were obtained every three months until 18 months at which time all mice developed multiple liver tumors. Nitrative DNA lesions and hepatocyte turnover were assessed immunohistochemically. Gene expression profiles were generated by extracting total RNA from the tissues and analyzing by microarray.ResultsThe nitrative DNA lesions and the regenerative proliferation of hepatocytes were increased during the progression of chronic liver disease. In a gene expression profile analysis of liver samples, the chemokine- and T cell receptor (TCR)-mediated pathways were enhanced during chronic hepatitis, and the EGF- and VEGF-mediated pathways were induced in HCC. Among these molecules, the protein levels of STAT3 were greatly enhanced in all hepatocyte nuclei and further elevated in the cytoplasm in HCC tissue samples at 18 months, and the levels of phosphorylated TP53 (p-p53-Ser 6 and -Ser 15) were increased in liver tissues.ConclusionsHBV-specific immune responses caused unique molecular signatures in the liver tissues of chronic hepatitis and triggered subsequent carcinogenic gene expression profiles in a mouse model. The results suggest a plausible molecular basis responsible for HBV-induced immune pathogenesis of HCC.

Hepatitis B virus–triggered autophagy targets TNFRSF10B/death receptor 5 for degradation to limit TNFSF10/TRAIL response

ABSTRACTDeath receptors of TNFSF10/TRAIL (tumor necrosis factor superfamily member 10) contribute to immune surveillance against virus-infected or transformed cells by promoting apoptosis. Many viruses evade antiviral immunity by modulating TNFSF10 receptor signaling, leading to persistent infection. Here, we report that hepatitis B virus (HBV) X protein (HBx) restricts TNFSF10 receptor signaling via macroautophagy/autophagy-mediated degradation of TNFRSF10B/DR5, a TNFSF10 death receptor, and thus permits survival of virus-infected cells. We demonstrate that the expression of the TNFRSF10B protein is dramatically reduced both in liver tissues of chronic hepatitis B patients and in cell lines transfected with HBV or HBx. HBx-mediated downregulation of TNFRSF10B is caused by the lysosomal, but not proteasomal, degradation pathway. Immunoblotting analysis of LC3B and SQSTM1, and microscopy analysis of tandem-fluorescence-tagged LC3B revealed that HBx promotes complete autophagy. Inhibition of autophagy with a pharmacological inhibitor and LC3B knockdown revealed that HBx-induced autophagy is crucial for TNFRSF10B degradation. Immunoprecipitation and GST affinity isolation assays showed that HBx directly interacts with TNFRSF10B and recruits it to phagophores, the precursors to autophagosomes. We confirmed that autophagy activation is related to the downregulation of the TNFRSF10B protein in liver tissues of chronic hepatitis B patients. Inhibition of autophagy enhanced the susceptibility of HBx-infected hepatocytes to TNFSF10. These results identify the dual function of HBx in TNFRSF10B degradation: HBx plays a role as an autophagy receptor–like molecule, which promotes the association of TNFRSF10B with LC3B; HBx is also an autophagy inducer. Our data suggest a molecular mechanism for HBV evasion from TNFSF10-mediated antiviral immunity, which may contribute to chronic HBV infection.

Measurement of the hepatitis B core-related antigen is valuable for predicting the pathological status of liver tissues in chronic hepatitis B patients

The objective of this study was to evaluate the validities of serum hepatitis B core-related antigen (HBcrAg) for predicting the pathological status of liver tissues of chronic hepatitis B (CHB). A total of 205 Chinese patients with CHB, including 121 HBeAg-positive and 84 HBeAg-negative patients, were enrolled in this study. In HBeAg-positive patients, AUCs of serum HBcrAg for predicting severe necro-inflammation and advanced fibrosis were greater than 0.70; using serum HBcrAg<=4.81×104kUmL−1 and <=2.45×104kUmL−1 as cutoffs, the sensitivities, specificities, accuracies for predicting severe necro-inflammation and advanced fbrosis were 0.697, 0.716, 0.711 and 0.818, 0.778, 0.785, respectively. In HBeAg-negative patients, the AUCs of serum HBcrAg for predicting significant necro-inflammation and significant fibrosis were greater than 0.70; using serum HBcrAg>=1.70×102kUmL−1 and >=4.02kUmL−1 as cutoffs, the sensitivities, specificities, accuracies for predicting significant necro-inflammation and significant fibrosis were 0.929, 0.964, 0.952 and 1.000, 1.000, 1.000, respectively. These results indicated favorable performances of serum HBcrAg for predicting severe necro-inflammation and advanced fibrosis in HBeAg-positive patients and significant necro-inflammation and significant fibrosis in negative patients.

Analysis of long-term follow-up and examination of pathological liver tissue in chronic hepatitis E

Hepatitis E is chronic in immunocompromised patients with HIV infection, organ transplant, or radiation and chemotherapy. General cases are not chronic. Fifty-five cases were collected and followed up for 4–14 years. It was found that chronic hepatitis E is more common in males, but a high degree of inflammatory activity and fibrosis was not evident. After 4–14 years of follow-up observation, cirrhosis or liver cancer did not appear. This is significantly different from the hepatitis B and C viruses. We speculated that the chronic mechanism in the general patients with hepatitis E might be different from that of immunocompromised cases.

Stat3 signaling activation crosslinking of TGF-β1 in hepatic stellate cell exacerbates liver injury and fibrosis

Background/AimsThe role of signal transducer and activator of transcription 3 (Stat3) in liver fibrosis is still controversial. Since hepatic stellate cells (HSCs) and transforming growth factor-β1 (TGF-β1) are central to the fibrogenesis, our goal was to clarify the mechanism of Stat3 crosslinking of TGF-β1 signaling. MethodsStat3, TGF-β1 mRNA and protein expressions were examined in liver tissues of chronic hepatitis B (CHB) patients and diethylinitrosamine (DEN)-induced rat fibrosis model. The effect of Stat3 activation or suppression on TGF-β1 signaling in HSCs was tested in vitro and in vivo. ResultsStat3 expression as well as TGF-β1 was increased in CHB patients and DEN-induced fibrosis rat model. This was strongly correlated with increase in fibrosis staging. TGF-β1, a mediator of fibrosis, was enhanced by Stat3, but suppressed by siRNA-mediated RNA knockdown of Stat3 (siStat3) or Janus kinase 2 inhibitor (AG490) both in vivo and in vitro. Stat3 crosslinking TGF-β1 signaling plays an important role in HSC activation and increasing fibrosis related products. TGF-β1 could not achieve profibrogenic cytokine and anti-apoptosis characteristics without Stat3 activation in HSCs. ConclusionWe provide a novel role of Stat3 cooperating TGF-β1 in activation and anti-apoptotic effect of HSCs. Stat3 worsens liver fibrosis through the up-regulation of TGF-β1 and fibrotic product expression.

Aberrant expression of claudin-4 and -7 in hepatocytes in the cirrhotic human liver.

The liver comprises hepatocytes and non-parenchymal cells such as bile duct epithelial cells. Claudin-4 and -7 are not expressed in hepatocytes under physiological conditions. It was reported that claudin-7 increased in human pulmonary fibroses. We therefore investigated claudin-4 and -7 expressions in human cirrhotic livers, in which hepatocyte proliferation is severely delayed. We examined liver tissues from 50 patients with liver tumors. The expression of claudin-4 and -7 in hepatocytes significantly increased with the grade of fibrosis, not with inflammatory activity, in the liver tissues of chronic hepatitis. The number of claudin-4- and -7-positive cells observed was greater than that of alpha-fetoprotein-positive hepatic progenitor cells. In primary cultures of mouse hepatocytes, the expression of claudin-4 and -7 was not induced by treatment with proinflammatory cytokines. In immunohistochemical analysis of liver tissues of 3,5-diethoxycarbonyl-1,4-dihydrocollidine-treated mice and primary cultures of mouse hepatocytes, the expression of claudin-4 and -7 increased with proliferation of progenitor cells. However, the claudin-4- and -7-positive cells were not always progenitor cells. Thus, claudin-4 and -7 were observed in hepatocytes of severely damaged mouse and human livers. These findings suggest that claudin-4- and -7-positive hepatocytes may exist during the process of differentiation from progenitor cells into mature hepatocytes.

Epigenetic silencing of sFRP1 activates the canonical Wnt pathway and contributes to increased cell growth and proliferation in hepatocellular carcinoma

The Wnt pathway is a key regulator of embryonic development and stem cells, and its aberrant activation is associated with human malignancies, most notably hepatocellular carcinoma (HCC). Epigenetic deregulation of the genes encoding the secreted frizzled-related proteins (sFRPs), the Wnt signalling antagonists, has been linked with aberrant hyperactivation of the Wnt signalling in HCC cells; however, the precise underlying mechanism remains elusive. We investigated the methylation profiles of Wnt antagonists in liver samples of different stages of HCC development and liver cancer cell lines and studied the functional impact of aberrant epigenetic silencing of sFRPs on the canonical Wnt pathway and cell viability. We found that the sFRP1 gene encoding the subunit is a frequent target of aberrant DNA hypermethylation and silencing in HCC tumours, whereas other extracellular Wnt antagonists, WIF1 and Dkk3, exhibited no methylation in tumour cells, consistent with the notion that aberrant methylation events in cancer cells are non-randomly distributed among the genes and that there is a strong preference for hypermethylation of specific genes in HCC. In addition, by comparing sFRP1 methylation status in HCC tumours with normal, cirrhotic and chronic hepatitis liver tissues, we identified sFRP1 gene as a potential early marker of HCC. The restoration of sFRP1 expression in cancer cells by ectopic expression inhibited Wnt activity accompanied with destabilization of β-catenin and downregulation of c-Myc and cyclin D1, the known downstream targets of Wnt pathway. Importantly, restoring sFRP1 levels in cancer cells inhibited cell growth and induced apoptotic cell death. This study supports the critical role for sFRP1 silencing in hepatocellular carcinoma and reinforces the importance of the Wnt antagonists in preventing oncogenic stabilization of β-catenin and chronic activation of the canonical Wnt pathway, suggesting that sFRP1 may be an attractive target for early cancer detection and therapeutic intervention.

Abstract 321: Aberrant methylation of multiple tumor suppressor genes and clinicopathological parameters as predictors for genotype-4 hepatitis C virus-associated hepatocellular carcinoma

Abstract Hepatocellular carcinoma (HCC) is one of the few tumors in which the incidence is on the rise worldwide. The increasing incidence of HCC is associated with the rise in hepatitis C virus (HCV) infection. It is estimated that 2.0% of the US general population are infected with HCV. Egypt has the highest prevalence of HCV/genotype 4 infection in the world, with 14% of the population infected. Little is known about the role(s) of epigenetic changes that may participate in HCV-induced HCC? Epigenetic studies directed at mapping the etiology of HCV disease progression to HCC and how they correlate with patients clinicopathological parameters are expected to provide new insights that will aid in the design of effective strategies for earlier detection and management of the disease, and therefore of great public/global health interest. The aim of the current study was to investigate the aberrant methylation of 11 genes in liver tissue samples obtained from Egyptian patients infected with HCV/genotype 4, and to explore possible relationships between aberrant methylation and clinicopathological features in HCC. Thirty-eight HCC and matching non-tumor tissues, thirty-one chronic hepatitis liver tissues, and thirteen normal liver tissues were analyzed for the methylation status of APC, FHIT, p15, p73, p14, p16, DAPK1, CDH1, RARβ, RASSF1A and O6MGMT genes by quantitative methylation-specific PCR. Based on methylation profiles using McNemar's test for paired binary data, a methylation of only 7 genes was found to be highly significant, which is dependent on disease state. For chronic hepatitis tissues, promoter methylation of p14 was highly significant in both liver tissues and peripheral blood leukocytes (PBL) (P &amp;lt; 0.0047 and &amp;lt;0.003, respectively), whereas methylation of RASSF1A was highly significant in normal liver tissues (P &amp;lt; 0.0005). For HCC, promoter methylation of p15, p14 and APC was highly significant in tumor tissues, non-tumor tissues, and PBL, respectively (P &amp;lt; 0.0001, &amp;lt; 0.0076 and &amp;lt; 0.0001, respectively). To account for the clinical variables of patients in the methylation status of a gene and disease state, a logistic regression analysis was performed. For HCC, promoter methylation of APC, DAPK1, and p14 was highly significant in addition to the blood profiles of patients (e.g., platelets, hemoglobin, WBCs levels). For patients with chronic hepatitis, methylation of CDH1 (E-Cadherin) was highly significant in addition to the patient's liver enzymes level (e.g., AST, ALT). Our data indicate that DNA methylation may serve as a marker for HCV-associated HCC, and demonstrate the importance of considering the clinicopathological variables as predicators of disease state. Quantitative analysis of methylated p14 may serve as a powerful molecular marker in detecting HCV disease progression to HCC. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 321. doi:10.1158/1538-7445.AM2011-321

Seroprevalence of antibody against Helicobacter pylori and identification of its specific genes in liver tissues of chronic hepatitis B virus infected patients

Objective To analyze the seroprevalence of Helicobacter pylori (H. pylori) infection and its specific genes in liver tissues of chronic hepatitis B virus (HBV) infected patients, and to investigate the effect of H. pylori on development of chronic HBV infected liver diseases. Methods Five hundred and two patients infected with HBV and 429 sex-and age matched healthy controls were enrolled in the case-control study. All subjects were tested for presence of antibodies against H. pylori using ELISA. Fifty-six liver biopsy samples were amplified by polymerase chain reaction (PCR) using Helicobacter genus-specific 16S rRNA primers. The positive samples were further amplified using specific primers of H. pylori cagA, vacA and glmM genes. Results H. pylori infection was accounted for 63.9% in HBV infected patients, which was higher than that in healthy controls (43.4%,P<0.05). Moreover, the seroprevalence of H. pylori in patients with hepatocellular carcinoma (HCC, 29/36,80.6%) or cirrhosis (64/83,77.1%) was higher than that in patients with chronic hepatitis (228/383,59.5%, P<0.01). Helicobacter genus-specific 16S rRNA was found in 17,7 or 11 of patients with cirrhosis, HCC or chronic hepatitis. Twenty-one samples were confirmed as H. pylori DNA by PCR. Conclusions The seroprevalence of antibody against H. pylori was higherHelicobacter can be detected in liver tissues of HBV infected patients. H. pylori might play the role in the development in HBV infected patients compared with healthy controls. Besides H. pylori, other of chronic hepatitis to cirrhosis and HCC. Key words: Helicobacter pylori; Hepatitis B; Live cirrhosis; Live neoplasms

Angiogenesis in chronic hepatitis C is associated with inflammatory activity grade and fibrosis stage

Data regarding the assessment of angiogenesis in liver tissue in chronic hepatitis C (CHC) are rare. The study was performed to explain the association between the histopathological features and the number of new blood vessels in lobules and portal tracts in CHC. The second aim of the study was to define the localization of sprouting and pattern of formation of new vessels by estimating CD 34 antigen expression in the liver. The study involved 74 patients with CHC, infected with viral genotype 1b before antiviral therapy. The number of new-formatted blood vessels was positively associated with fibrosis stage and inflammatory activity grade in the liver biopsy from CHC patients. The relationship was evident in the portal tract, fibrous septa and periportal zones of lobules. The results suggest that inflammatory hepatocyte injury may promote neo-angiogenesis.

Expression of SOCS-1 in the liver tissues of chronic hepatitis B and its clinical significance

To study the expression of suppressor of cytokine signaling-1 (SOCS-1) in the liver tissues of chronic hepatitis B (CHB) and the clinical significance of this expression. The expression of SOCS-1 in liver tissues of 45 cases of CHB was investigated by immunohistochemical staining, and its correlations with inflammation grades and fibrosis stage were analyzed by SPSS statistics software. The result showed SOCS-1 expressing could be observed in the liver tissue of CHB. The expression of SOCS-1 was mainly distributed near the portal area in the liver tissue of mild inflammation CHB group, and was diffusely distributed in the liver tissue of moderate and severe inflammation groups. SOCS-1 positive stains mainly appear in the hepatocytes, only a few of liver interstitial cells were involved. Inside the hepatocyte, SOCS-1 positive stains are mainly distributed in the plasma. Some of the staining was observed on the membrane. The inclusion bodies in the plasma of hepatocytes were observed occasionally. There were both obvious correlations between the expression of SOCS-1 and the inflammatory grade, and that between the expression of SOCS-1 and the fibrosis stage. The distribution of SOCS-1 in the liver tissue of CHB is variable. This expression was correlated with the inflammation grade and fibrosis stage.

The Fas concentrations in the serum and liver tissue in chronic hepatitis B patients treated with lamivudine

The Fas concentrations in the serum and liver tissue in chronic hepatitis B patients treated with lamivudine

Immunohistochemical localization of CEA, CA19-9 and DU-PAN-2 in hepatitis C virus-infected liver tissues.

We investigated expression of CEA, CA19-9 and DU-PAN-2 in liver tissues of chronic hepatitis, liver cirrhosis and hepatocellular carcinoma, measuring their serum value to clarify their clinical significance, and proliferating cell nuclear antigen (PCNA) was assessed in serial sections to determine whether expression of these molecules in chronic liver disease was related to regeneration of biliary ducts. Liver tissues were biopsied under peritoneoscopy or echo-guidance and resected surgically among 63 patients with anti-hepatitis C virus-positive sera. There were 26 cases of chronic hepatitis, 21 cases of liver cirrhosis and 16 cases of hepatocellular carcinoma (four cases of mixed type). They were simultaneously used for immunocytochemistry for CEA, CA19-9 and DU-PAN-2, and PCNA was demonstrated in serial liver tissues by immunohistochemistry. Serum CEA, CA19-9 and DU-PAN-2 were measured by radioimmunoassay or enzyme immunoassay. In chronic hepatitis and liver cirrhosis CEA immunoreactivity was seen on membranes facing bile canaliculi and in bile ductules. Both CA19-9 and DU-PAN-2 immunoreactivity were observed in bile ductules in chronic hepatitis liver cirrhosis and non-neoplastic areas surrounding hepatocellular carcinoma, and CA19-9 was also present in interlobular bile ducts. PCNA immunoreactivity was not detected in marker-positive bile ductules or interlobular bile ducts. In hepatocellular carcinoma CEA immunoreactivity was seen on membrane facing dilated bile canaliculi in glandular structures, and CEA, CA19-9 and DU-PAN-2 immunoreactivity was observed in cholangiolar areas in mixed type of hepatocellular carcinoma. CEA in chronic hepatitis and liver cirrhosis is expressed not only in bile ductules but also on membrane facing bile canaliculi, and both CA19-9 and DU-PAN-2 were seen in different levels of biliary ducts. These molecules were expressed in bile ductules in surrounding non-neoplastic areas of hepatocellular carcinoma, and their expression was not associated with regeneration of biliary ducts. CEA expression was present in the trabecular type of hepatocellular carcinoma, and CA19-9 and DU-PAN-2 were observed in cholangiolar areas in mixed type of hepatocellular carcinoma.

Expression of Hepatocyte Growth Factor Activator and Hepatocyte Growth Factor Activator Inhibitor Type 1 in Human Hepatocellular Carcinoma

Hepatocyte growth factor activator inhibitor type 1 (HAI-1), a Kunitz-type serine protease inhibitor for hepatocyte growth factor activator (HGFA), is responsible for proteolytic activation of hepatocyte growth factor. We examined the expression of HGFA and HAI-1 in liver tissues of chronic liver diseases including hepatocellular carcinoma (HCC). HGFA expression was detected not only in the liver tissues of chronic hepatitis and cirrhosis and in the nontumorous liver tissues surrounding HCC, but also in HCC tissues. On the other hand, none of the liver tissues of hepatitis and cirrhosis and none of the nontumorous tissues surrounding HCC were stained with anti-HAI-1. However, 35% of HCC tissues were stained with anti-HAI-1, and HAI-1 positivity increased as the histological grade decreased and as serum α-fetoprotein increased. Transduction of antisense HAI-1 inhibited the growth of human hepatoma cells. These results suggest the possibility that HAI-1 plays an important role in the progression of HCC.

Involvement of Annexins I an II in human liver cirrhosis and hepatocellular carcinoma

Annexin (AX) is the name of a new family of Ca 2+-dependent membrane binding proteins of which 13 members have been reported to date. Among these, AXI and AXII have been reported to possess many biological functions in vitro. Their actual roles in vivo, however, are as yet unknown. There have been no reports previously demonstrating the direct involvement of AXI and AXII in chronic hepatitis (CH), liver cirrhosis (LC) or hepatocellular carcinoma (HCC). The involvement of AXI and AXII in the etiological processes of CH, LC and HCC was investigated by Western blot and/or immunohistochemistry using anti-AXI and AXII antibodies. AXI and AXII were rarely detected in CH liver tissues, while they were found to be expressed at high levels in LC and HCC. AXI and AXII were present in the hepatocytes of LC and HCC and their subcellular localization was mainly cytoplasmic. These results indicate that AXI and AXII may act together in the occurrence and development of LC and HCC.

Tenascin expression in human chronic liver disease and in hepatocellular carcinoma.

Tenascin is an oligomeric glycoprotein of the extracellular matrix synthesized during embryonic development. It is prominently expressed in a variety of tumors. The role of tenascin in liver tissue is, however, unknown. We used immunocytochemistry to define the localization of tenascin and compare this with the localization of non-collagenous proteins, such as laminin and fibronectin, in normal human liver and pathological liver from patients with chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. In normal liver, tenascin expression was localized along the sinusoidal and vascular wall. In fibrotic liver, tenascin was also observed in the region between the hepatic parenchyma and the fibrosing portal tracts, especially in areas of piecemeal necrosis in chronic hepatitis. Immuno-EM study of liver tissue in chronic hepatitis strongly suggested the synthesis and secretion of tenascin by fat-storing cells into the space of Disse. In hepatocellular carcinoma, tenascin was expressed in both the capsule and lobular septa, but not in the sinusoidal walls of the tumors. These results led us to postulate a close relationship between the occurrence of this protein and disease processes such as fibrosis and cancer invasion.

Annexin A2 expression and phosphorylation are up-regulated in hepatocellular carcinoma

Annexins (ANXs) constitute a family of Ca2+-dependent membrane-binding proteins; at least 20 of them have been described to date. Among these, Annexin A2 (ANXA2) has been revealed as a multi-functional protein in vitro. Its actual role in vivo, however, requires further investigation. We already reported that ANX-I (ANXA1) was up-regulated in hepatocellular carcinoma (HCC). The role of ANXA2 in various liver diseases including HCC remains obscure. In the present study, the protein and mRNA levels of ANXA2, as well as its localization, were determined for the normal human liver, chronic hepatitis liver, and non-tumorous and tumorous portions of HCC tissues. ANXA2 was rarely detected in either normal or chronic hepatitis liver tissues, whereas it was overexpressed at both the transcriptional and translational levels in tumorous and non-tumorous regions of HCC. In addition, in many cases, more ANXA2 was expressed in the tumorous portion than in the non-tumorous portion of HCC. The expression of ANXA2 was mainly localized in cancer cells, especially in poorly differentiated HCC. Furthermore, ANXA2 was tyrosine-phosphorylated in HCC. These data suggest that overexpression and tyrosine phosphorylation of ANXA2 play important roles in the malignant transformation process leading to HCC and are related to the histological grade of HCC.

慢性肝炎患者における末梢静脈血中ロイコトリエンについて

The leukotrienes are derived from arachidonic acid via a lipoxigenase pathway and are potent mediators of inflammation and allergy. Leukotriene B4 (LTB4) not only causes chemotaxis, chemokinesis and degranulation of polymorphonuclear leukocytes but also involves in the enhanced production of interleukin 1 from macrophages, interleukin 2 and interferon-gamma production from T lymphocytes and activation of natural killer (NK) cells. Leukotriene C4 (LTC4) enhances vascular permeability and induces tissue edema. Recently, it is suggested that leukotrienes may be key mediators in inflammatory liver diseases. In this study, to clarify the relation of leukotrienes to liver injury, we have examined the blood levels of LTB4 and LTC4 in chronic hepatitis.Leukotrienes were assayed using with the combination of technique of reverse-phase high-performance liquid chromatography and radioimmunoassay.The following results were obtained. (a) The blood level of LTB4 in chronic hepatitis was significantly higher than control group. (b) No significant difference of blood level of LTC4 between chronic hepatitis and control group was obtained.These results suggested that increased levels of LTB4 may be involved in the inflammatory and immunologic events in liver tissue in chronic hepatitis.