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Annals of Internal Medicine | 1999

Interferon Therapy Reduces the Risk for Hepatocellular Carcinoma: National Surveillance Program of Cirrhotic and Noncirrhotic Patients with Chronic Hepatitis C in Japan

Haruhiko Yoshida; Yasushi Shiratori; Mitsuhiko Moriyama; Yasuyuki Arakawa; Tatsuya Ide; Michio Sata; Osami Inoue; Michitami Yano; Motohiko Tanaka; Shigetoshi Fujiyama; Shuhei Nishiguchi; Tetsuo Kuroki; Fumio Imazeki; Osamu Yokosuka; Shingo Kinoyama; Gotaro Yamada; Masao Omata

Hepatitis C virus (HCV) infection rarely resolves spontaneously once it becomes chronic (1). Most patients remain asymptomatic for a long period, with liver cirrhosis developing after approximately 30 years (2, 3). Chronic hepatitis C with cirrhosis is a major risk factor for hepatocellular carcinoma (4-7). It has been previously shown that the risk increases with the degree of liver fibrosis (5). Interferon is the only agent known to be effective against HCV infection (8-10). It induces a sustained virologic response in 15% to 30% of patients (11-14). Responders usually show biochemical and histologic improvement (9, 11, 15). Recently, interferon therapy in patients with chronic hepatitis C and cirrhosis was shown to be associated with a reduced incidence of hepatocellular carcinoma (16). Because most patients treated with interferon do not have cirrhosis, we included noncirrhotic as well as cirrhotic patients in our analysis of the effect of interferon therapy on the incidence and prevention of hepatocellular carcinoma. A national surveillance program, the Inhibition of Hepatocarcinogenesis by Interferon Therapy (IHIT) Study, was begun in 1994 as a multicenter, large-scale, retrospective cohort study supported by the Japan Ministry of Health and Welfare as one of the Comprehensive 10-Year Strategy for Cancer Control Projects (17). In this program, patients with chronic hepatitis C who have undergone liver biopsy at one of eight participating institutions are enrolled and followed periodically for development of hepatocellular carcinoma by using several imaging techniques. We analyzed the incidence of hepatocellular carcinoma as of February 1998 by using multivariate proportional hazards regression. Methods Patients The IHIT Study Group approved the design of this study on 21 September 1994. All patients who were positive by a second-generation HCV antibody assay and who had undergone liver biopsy since 1986 at one of the eight participating institutions were enrolled. Patients who were participants in interferon trials for non-A, non-B chronic hepatitis (18-21) and in whom anti-HCV seropositivity was confirmed by using stored sera were also included; these patients had undergone liver biopsy in 1986 or later. Patients were excluded if at the time of liver biopsy they presented with hepatocellular carcinoma or other liver diseases, such as chronic hepatitis B, alcoholic liver disease,autoimmune hepatitis, or primary biliary cirrhosis. The minimum follow-up was established as 1 year for two reasons. First, if hepatocellular carcinoma is detected within 1 year after liver biopsy, the possibility that the cancer was present at the time of liver biopsy cannot be ruled out. Second, interferon therapy must be started within 1year after liver biopsy according to Japanese health insurance rules. By February 1998, 3223 patients who fulfilled the inclusion criteria were registered. Of these patients, 333 were excluded from the analysis: 161 patients (5.0%) transferred to other hospitals without follow-up, and the follow-up period after liver biopsy was less than 1 year for172 patients (5.3%). Thus, 2890 patients were included in the present analysis. Figure 1 shows the schema for patient selection. Figure 1. Schema for patient selection. Interferon therapy was given to 2400 patients; 490patients did not receive treatment (control group). Interferon therapy was initiated within 1 year after liver biopsy (within 6 months in 93% of patients); 84% of patients received interferon-, 14% received interferon-, and 2% received a combination of interferon- and interferon-. The median total dose was 480 MU (first quartile, 324 MU; third quartile, 702 MU), and the median duration of administration was 160 days(first quartile, 94 days; third quartile, 168 days). Once interferon therapy was started, a patient was included in the interferon treatment group even if therapy was discontinued because of adverse events or other reasons. The 490patients who did not receive interferon chose this course of action voluntarily on the basis of concerns about adverse effects; lack of time for therapy; or physician recommendation, which took into account depression, severe diabetes mellitus, or other medical conditions. Serum HCV load was quantitatively determined at the timeof liver biopsy by using various commercial and in-house assays. Because it is difficult to correlate the results of different assay methods, only data obtained with two widely used assays, the branched-DNA probe assay (22) and competitive reverse-transcription polymerase chain reaction (RT-PCR) (23), were used. HCV RNA genotype was determined by RT-PCR using genotype-specific primers (24) or by serologic grouping of serum antibody (25), assuming that genotypes 1a and 1b correspond to serologic group 1 (genotype 1) and genotypes 2a and 2b correspond to serologic group 2 (genotype 2) (11). Histologic Evaluation Liver biopsy specimens were evaluated by a representative pathologist at each institution (a total of eight pathologists were involved) and were scored for the stage of liver fibrosis and grade of inflammatory activity according to the classification of Desmet and colleagues (26). Stage of fibrosis was assessed from stage F0 (no fibrosis) to stage F4 (cirrhosis), and grade of inflammatory activity was scored from grade A1 (mild) to grade A3 (severe). To confirm interobserver concordance in scoring, a subsequent blind and independent examination of 350randomly selected liver biopsy specimens was conducted by two of the eight pathologists. Definition of Interferon Response Virologic and biochemical criteria were used to define response to interferon therapy. Hepatitis C virus RNA was used as a marker of virologic response and was determined by RT-PCR. A virologic sustained response was defined as HCV RNA negativity more than 6 months after termination of interferon therapy; positivity at the same time point was considered a nonsustained response (27). Patients with nonsustained response included those who had temporary disappearance of viremia followed by relapse. In patients treated before the availability of RT-PCR, virologicresponse was determined by using sera stored at 30 C or collected afterward. The serum alanine aminotransferase (ALT) level was used as a marker of biochemical response to interferon therapy. Sustained biochemical response was defined as persistently normal serum ALT levels more than 6 months after termination of interferon therapy; nonsustained response was defined as elevated serum ALT levels at the same time point. Nonsustained response was subdivided into two categories: mildly elevated for a serum ALT level less than two times the upper limit of normal and highly elevated for a serum ALT level two or more times the upper limit of normal. Screening for Hepatocellular Carcinoma Patients were examined for hepatocellular carcinoma by abdominal ultrasonography at least every 6 months. If hepatocellular carcinoma was suspected on the basis of ultrasonographic results, additional procedures, such as computed tomography, magnetic resonance imaging, abdominal angiography, and ultrasonography-guided tumor biopsy, were used to confirm the diagnosis. Statistical Analysis Statistical analysis was performed by using SAS software, version 6.12 (SAS Institute, Inc., Cary, North Carolina). Interobserver concordance of histologic scoring was evaluated by using the Spearman correlation coefficient. Differences between two groups were evaluated by using the unpaired Student t-test or the Mann-Whitney U-test. Categorical data were compared by using the chi-square test or the Fisher exact probability test. Cumulative incidence curves were determined with the Kaplan-Meier method, and the differences between groups were assessed by using the log-rank test. We used the Cox proportional-hazards regression analysis to examine the effect of interferon therapy on the incidence of hepatocellular carcinoma. Because virologic and biochemical responses were mutually dependent, the risk ratio for hepatocellular carcinoma was calculated separately for these factors. The risk ratio attributable to categorical data, such as stage of liver fibrosis and serum ALT level, was calculated by using dummy variables. A P value less than 0.05 was considered statistically significant. Results Patient Characteristics The demographic and clinical features of patients at the time of their enrollment are summarized in Table 1. The frequency distribution of the stages of liver fibrosis differed between interferon-treated patients and untreated patients. Most laboratory values also differed between the two groups. However, differences in laboratory values between treated patients and untreated patients were not significant at the same stage of fibrosis. This indicated the need to adjust for stage of liver fibrosis, which was done in the following analyses. Table 1. Demographic and Clinical Characteristics Histologic Evaluation The concordance in scores for stage of fibrosis and grade of inflammatory activity determined at each institution and by the two representative pathologists was strong, with Spearman coefficients ranging from 0.897 to 0.918 for stage of fibrosis and from 0.878 to 0.849 for grade of inflammatory activity. The original score was sustained by at least one of the two pathologists in 319 of 350 cases for fibrosis staging and in 320 of 350cases for grading inflammatory activity. Response to Interferon Therapy Response to interferon therapy was determined in 2357(98.2%) of the 2400 interferon-treated patients. Response was not determined in43 patients because of insufficient follow-up (<6 months) after termination of therapy. A sustained virologic response was achieved in 789 patients(33.5%). The response rate was similar regardless of the type of interferon used (32.3%, 34.5%, and 25.6% for interferon-, interferon-, and the combination of the two, respectively). A sustained bioch


Hepatology Research | 2007

Persistent infection of hepatitis E virus transmitted by blood transfusion in a patient with T-cell lymphoma.

Akinori Tamura; Yohko K. Shimizu; Torahiko Tanaka; Kazumichi Kuroda; Yasuyuki Arakawa; Kazuaki Takahashi; Shunji Mishiro; Kazufumi Shimizu; Mitsuhiko Moriyama

Aim:  With advent of reverse‐transcription (RT)/polymerase chain reaction (PCR) for detection of the hepatitis E viral genome, we carried out retrospective examinations.


Journal of Virology | 2000

Hepatitis C Virus Core Protein Interacts with 14-3-3 Protein and Activates the Kinase Raf-1

Hiroshi Aoki; Junpei Hayashi; Mitsuhiko Moriyama; Yasuyuki Arakawa; Okio Hino

ABSTRACT Persistent hepatitis C virus (HCV) infection is a major cause of chronic liver dysfunction in humans and is epidemiologically closely associated with the development of human hepatocellular carcinoma. Among HCV components, core protein has been reported to be implicated in cell growth regulation both in vitro and in vivo, although mechanisms explaining those effects are still unclear. In the present study, we identified that members of the 14-3-3 protein family associate with HCV core protein. 14-3-3 protein bound to HCV core protein in a phosphoserine-dependent manner. Introduction of HCV core protein caused a substantial increase in Raf-1 kinase activity in HepG2 cells and in a yeast genetic assay. Furthermore, the HCV core–14-3-3 interaction was essential for Raf-1 kinase activation by HCV core protein. These results suggest that HCV core protein may represent a novel type of Raf-1 kinase-activating protein through its interaction with 14-3-3 protein and may contribute to hepatocyte growth regulation.


Cancer | 2002

Serum concentrations of human hepatocyte growth factor is a useful indicator for predicting the occurrence of hepatocellular carcinomas in C-viral chronic liver diseases

Hiroaki Yamagamim; Mitsuhiko Moriyama; Hiroshi Matsumura; Hiroshi Aoki; Toshihiro Shimizu; Takahide Saito; Miki Kaneko; Atsuo Shioda; Naohide Tanaka; Yasuyuki Arakawa

Numerous reports have examined the relationship between hepatocyte growth factor (HGF) and either the facilitation or suppression of the occurrence of hepatocellular carcinoma (HCC).


Intervirology | 1999

Hepatitis C Virus and Hepatocarcinogenesis

Junpei Hayashi; Hiroshi Aoki; Yasuyuki Arakawa; Okio Hino

Although human hepatocellular carcinoma (HCC) is one of the most common types of tumors in the world, the molecular mechanisms underlying hepatitis-C-related human hepatocarcinogenesis are still not clear. HCC is accompanied by virus infections in most cases, and it is suggested that hepatitis B virus and hepatitis C virus (HCV) significantly influence the oncogenic process. The persistence of inflammation following HCV infection is reportedly related to carcinogenesis, and the mechanism of chronic inflammation has been approached by taking viral, immunologic, cytokine and apoptotic responses into consideration. With the progress made in molecular biology, the functional abnormality of oncogenes/tumor suppressor genes has been identified and, apart from the p53 gene, involvement of the IGF-II gene has also been described recently. Furthermore, it has been suggested that uncontrolled proliferation of cancer cells might be based on abnormal regulation of intracellular signal transduction pathways. Here we review the cutting edge of molecular hepatitis C virology in terms of virus-cell interactions, which may contribute to the development of human HCCs. We also discuss the recent progress made in the molecular and cell biology of human hepatocarcinogenesis.


Journal of Hepatology | 1997

Quantitative assays for hepatitis C virus in serum as predictors of the long-term response to interferon

Yasushi Shiratori; Naoya Kato; Osamu Yokosuka; Etsuko Hashimoto; Naoaki Hayashi; Akira Nakamura; Manabu Asada; Hisamoto Kuroda; Hitoshi Ohkubo; Yasuyuki Arakawa; Akisuke Iwama; Masao Omata

BACKGROUND/AIMS Interferon therapy has a beneficial effect in patients with chronic hepatitis C who have a low viral load. The aim of this study was to compare the core protein level with HCV RNA levels and to analyze whether virus quantitation predicts the efficacy of interferon therapy. METHODS HCV core protein level assessed by the recently developed assay was compared with HCV RNA levels measured by three different methods (Amplicor-HCV monitor, competitive RT(CRT)-PCR, and bDNA probe assay) in 352 patients with chronic hepatitis C in relation to viral serotype. RESULTS From 91% (320/352) to 93% (299/322) of patients with viremia were detected by Amplicor-monitor and CRT-PCR, in contrast to 60% (187/312) and 74% (191/258) by bDNA and HCV core protein assay, respectively. The HCV core protein level was positively correlated with HCV RNA levels measured by the three assays (r = 0.680 to 0.731). Serum HCV RNA and core protein levels were significantly lower in patients with serotype 2 than in those with serotype 1. Viral eradication after interferon therapy was observed in 60-70% of the patients with < 1 x 10(4) copies/ml of HCV RNA by Amplicor-monitor assay, < 2 x 10(5) copies/ml by CRT-PCR, < 0.5 Meq/ml by bDNA assay, and < 20 pg/ml of core protein by HCV core protein assay. Viral eradication was uncommon (< 11%) among the patients with higher viral loads. Bivariate analysis revealed that the outcome of interferon therapy was more closely associated with both HCV core protein and RNA levels than the HCV serotype. CONCLUSIONS Quantitation of HCV core protein and HCV RNA in useful for prediction of the interferon response.


Journal of Gastroenterology | 2004

The protective and hormonal effects of proanthocyanidin against gastric mucosal injury in Wistar rats

Yoshikazu Iwasaki; Teruaki Matsui; Yasuyuki Arakawa

BackgroundProanthocyanidin, a grape-seed polyphenol, has been reported to have protective properties against vascular injury and ulcers, preventive effects against atherosclerosis and cancer, and antioxidative effects, such as improving lipid metabolism and slowing aging. However, little has been reported on its antiulcer effects. We aimed to elucidate the antiulcer mechanism of proanthocyanidin.MethodsGravinol, containing 89.3% proanthocyanidin, was used. Proanthocyanidin solution, in distilled water, at 0.002%, 0.02%, 0.2%, or 1%, was given to rats ad libitum for 2 weeks. Distilled water was given to control rats. The effect of proanthocyanidin on gastric mucosal injury was investigated with the water-immersion restraint stress model. The ratios of areas of hemorrhagic erosion were compared as the lesion index. Myeloperoxidase activities were also examined, as an index of tissue injury. Superoxide dismutase activity was measured to examine its antioxidative effect. Furthermore, serum gastrin, somatostatin, histamine, and prostaglandin E2 levels were measured in this rat model.ResultsProanthocyanidin administration significantly suppressed gastric mucosal injury, induced by water-immersion restraint stress, in a dose-dependent manner. Myeloperoxidase activities were also significantly inhibited, whereas superoxide dismutase activities were significantly stimulated. As to gastrointestinal hormones, the secretion of gastrin, somatostatin, and histamine was significantly inhibited, while prostaglandin E2 secretion was significantly stimulated.ConclusionsProanthocyanidin was shown to have a protective effect on the gastric mucosa. The mechanisms underlying the effect of proanthocyanidin were considered to be the following: anti-gastrin and anti-histamine effects to prevent attacks by water-immersion restraint stress, and mucoprotective properties, bestowed by increased prostaglandin and increased superoxide dismutase activities in the gastric mucosa.


Intervirology | 2000

The Clinical Features of Chronic Hepatitis C Are Not Affected by the Coexistence of Hepatitis B Virus DNA in Patients Negative for Hepatitis B Surface Antigen

Kazushige Nirei; Miki Kaneko; Mitsuhiko Moriyama; Yasuyuki Arakawa

Hepatitis B virus (HBV) DNA has been detected in the sera of hepatitis patients who are negative for hepatitis B surface antigen (HBsAg) by polymerase chain reaction (PCR). The purpose of the present study was to clarify the clinical characteristics of patients with chronic hepatitis C who are negative for serum HBsAg and positive for HBV DNA. The subjects included 49 patients with chronic hepatitis C who were negative for serum HBsAg and 119 blood donors who served as healthy controls. Serum samples were tested for the presence of HBV DNA by the nested PCR method. Serum HBV DNA was detected in 18 (37.7%) of the 49 chronic hepatitis C patients and in none (0%) of the 119 blood donors. Among the hepatitis C patients, HBV DNA was detected in 20.7% of those who were negative for all HBV-associated markers and in 57.1% of those who were positive for one or more HBV-associated marker. The HBV DNA-positive rate among those in each F stage did not significantly differ. The liver function parameters of the HBV DNA-positive and the HBV DNA-negative chronic hepatitis C patients did not significantly differ. These results suggest that hepatitis C virus is frequently coinfected with serum HBsAg-negative HBV, and that the incidence of HBV infection in blood donors is low. However, it is considered that HBsAg-negative HBV infection does not modify the blood biochemical features of chronic hepatitis C.


Journal of Clinical Microbiology | 2001

Molecular Characteristic-Based Epidemiology of Hepatitis B, C, and E Viruses and GB Virus C/Hepatitis G Virus in Myanmar

Kazuhiko Nakai; Khin Maung Win; San San Oo; Yasuyuki Arakawa; Kenji Abe

ABSTRACT We carried out a molecular characteristic-based epidemiological survey of various hepatitis viruses, including hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis E virus (HEV), and GB virus C (GBV-C)/hepatitis G virus (HGV), in Myanmar. The study population of 403 subjects consisted of 213 healthy individuals residing in the city of Yangon, Myanmar, and the surrounding suburbs and 190 liver disease patients (155 virus-related liver disease patients and 35 nonviral disease patients). The infection rates of the viruses among the 213 healthy subjects were as follows: 8% for HBV (16 patients), 2% for HCV (4 patients), and 8% for GBV-C/HGV (17 patients). In contrast, for 155 patients with acute hepatitis, chronic hepatitis, liver cirrhosis, or hepatocellular carcinoma, the infection rates were 30% for HBV (46 patients), 27% for HCV (41 patients), and 11% for GBV-C/HGV (17 patients). In the nonviral liver disease group of 35 patients with alcoholic liver disease, fatty liver, liver abscess, and biliary disease, the infection rates were 6% for HBV (2 patients), 20% for HCV (7 patients), and 26% for GBV-C/HGV (9 patients). The most common viral genotypes were type C of HBV (77%), type 3b of HCV (67%), and type 2 of GBV-C/HGV (67%). Moreover, testing for HEV among 371 subjects resulted in the detection of anti-HEV immunoglobulin G (IgG) in 117 patients (32%). The age prevalence of anti-HEV IgG was 3% for patients younger than 20 years and 30% or more for patients 20 years of age or older. Furthermore, a high prevalence of anti-HEV IgG (24%) was also found in swine living together with humans in Yangon. These results suggest that these hepatitis virus infections are widespread in Myanmar and have led to a high incidence of acute and chronic liver disease patients in the region.


Journal of Hepatology | 1993

Detection of precore/core-mutant hepatitis B virus genome in patients with acute or fulminant hepatitis without serological markers for recent HBV infection

Toshikazu Uchida; Thein Thein Aye; Sven O. Becker; Masanori Hirashima; Toshio Shikata; Fumihiko Komine; Mitsuhiko Moriyama; Yasuyuki Arakawa; Shyujirou Takase; Satoaki Mima

To confirm the possibility that some hepatitis B virus (HBV) variants do not induce HB s antigen (HBsAg), anti-HB core antibody (anti-HBc) and anti-HBc IgM in a transient infection, polymerase chain reaction (PCR) was performed in 20 patients with acute hepatitis and 7 patients with fulminant hepatitis. Patients were diagnosed with non-A, non-B hepatitis by serological markers at admission. PCR successfully amplified the precore/core gene in 5 (25%) of the patients with acute hepatitis and 2 (29%) of the patients with fulminant hepatitis. Subsequent sequencing revealed frequent mutations including precore-defects in the precore/core gene.

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