Michio Sata

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

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

Therapeutic effects of restricted diet and exercise in obese patients with fatty liver

BACKGROUND/AIMS The incidence of obese patients with fatty liver has recently increased in Japan as well as in the United States and Europe. Fatty liver may occasionally progress to liver cirrhosis. In this study, we have compared the effects of restricted diet and exercise versus no treatment in obese patients with fatty liver. METHODS Twenty-five obese patients with fatty liver were divided into treated and control groups. Fifteen obese patients followed a program of restricted diet (ideal weight x 25 Cal x kg(-1)) and exercise (walking or jogging) for a trial period of 3 months. No changes in diet or lifestyle were made by the other 10 patients during the same trial period. Blood biochemical tests and liver histology were compared in all patients before and after the trial. RESULTS In the treated group, weight, blood biochemical data such as aminotransferase, albumin, cholinesterase, total cholesterol and fasting blood glucose values, and steatosis were significantly decreased after the trial. In the control group, there were no significant differences in the clinical and histological findings before and after the trial. CONCLUSIONS These results indicate that restricted diet and exercise therapy, such as walking and jogging, are useful means of improving blood biochemical data and histological findings in liver tissues related to fatty liver.

Hepatitis C virus down-regulates insulin receptor substrates 1 and 2 through up-regulation of suppressor of cytokine signaling 3

The pathogenesis of hepatitis C virus (HCV)-associated insulin resistance remains unclear. Therefore, we investigated mechanisms for HCV-associated insulin resistance. Homeostasis model assessment for insulin resistance was increased in patients with HCV infection. An increase in fasting insulin levels was associated with the presence of serum HCV core, the severity of hepatic fibrosis and a decrease in expression of insulin receptor substrate (IRS) 1 and IRS2, central molecules of the insulin-signaling cascade, in patients with HCV infection. Down-regulation of IRS1 and IRS2 was also seen in HCV core-transgenic mice livers and HCV core-transfected human hepatoma cells. Carbobenzoxy-l-leucyl-l-leucyl-l-leucinal, a potent proteosomal proteolysis inhibitor, blocked down-regulation of IRS1 and IRS2 in HCV core-transfected hepatoma cells. In human hepatoma cells, HCV core up-regulated suppressor of cytokine signaling (SOCS) 3 and caused ubiquitination of IRS1 and IRS2. HCV core-induced down-regulation of IRS1 and IRS2 was not seen in SOCS3(-/-) mouse embryonic fibroblast cells. Furthermore, HCV core suppressed insulin-induced phosphorylation of p85 subunit of phosphatidylinositol 3-kinase and Akt, activation of 6-phosphofructo-2-kinase, and glucose uptake. In conclusion, HCV infection changes a subset of hepatic molecules regulating glucose metabolism. A possible mechanism is that HCV core-induced SOCS3 promotes proteosomal degradation of IRS1 and IRS2 through ubiquitination.

Daclatasvir Plus Asunaprevir for Chronic HCV Genotype 1b Infection

All‐oral combinations of direct‐acting antivirals may improve efficacy and safety outcomes for patients with hepatitis C virus (HCV) infection, particularly those who are poor candidates for current interferon/ribavirin‐based regimens. In this open‐label, phase 3 study, 135 interferon‐ineligible/intolerant and 87 nonresponder patients with chronic HCV genotype 1b infection were enrolled at 24 centers in Japan. Patients received daclatasvir 60 mg once daily plus asunaprevir 100 mg twice daily for 24 weeks. The primary endpoint was sustained virologic response 24 weeks after treatment (SVR24). This study is registered with ClinicalTrials.gov (NCT01497834). SVR24 was achieved by 87.4% of interferon‐ineligible/intolerant patients and 80.5% of nonresponder (null and partial) patients; rates were similar in cirrhosis (90.9%) and noncirrhosis (84.0%) patients, and in patients with IL28B CC (84.5%) or non‐CC (84.8%) genotypes. Fourteen patients in each group (12.6%) discontinued dual therapy, mainly due to adverse events or lack of efficacy. Nine nonresponder patients received additional treatment with peginterferon/ribavirin per protocol‐defined criteria. The rate of serious adverse events was low (5.9%) and varied among patients. The most common adverse events were nasopharyngitis, increased alanine aminotransferase (ALT) and aspartate aminotransferase (AST), headache, diarrhea, and pyrexia. Conclusion: Interferon‐free, ribavirin‐free all‐oral therapy with daclatasvir and asunaprevir for 24 weeks is well tolerated and can achieve a high rate of SVR in patients with HCV genotype 1b who were ineligible, intolerant, or had not responded to prior interferon‐based therapy. (Hepatology 2014;59:2083–2091)

Hepatic arterial infusion chemotherapy for advanced hepatocellular carcinoma with portal vein tumor thrombosis: analysis of 48 cases.

The prognosis of patients with hepatocellular carcinoma (HCC) with portal vein tumor thrombosis (PVTT) is extremely poor. The aim of this study was to elucidate the efficacy of hepatic arterial infusion chemotherapy (HAIC) for patients with advanced HCCs.

Activation of STAT3 by the Hepatitis C Virus Core Protein Leads to Cellular Transformation

The signal transducer and activator of transcription (STAT) family proteins are transcription factors critical in mediating cytokine signaling. Among them, STAT3 is often constitutively phosphorylated and activated in human cancers and in transformed cell lines and is implicated in tumorigenesis. However, cause of the persistent activation of STAT3 in human tumor cells is largely unknown. The hepatitis C virus (HCV) is a major etiological agent of non-A and non-B hepatitis, and chronic infection by HCV is associated with development of liver cirrhosis and hepatocellular carcinoma. HCV core protein is proposed to be responsible for the virus-induced transformation. We now report that HCV core protein directly interacts with and activates STAT3 through phosphorylation of the critical tyrosine residue. Activation of STAT3 by the HCV core in NIH-3T3 cells resulted in rapid proliferation and up-regulation of Bcl-XL and cyclin-D1. Additional expression of STAT3 in HCV core-expressing cells resulted in anchorage-independent growth and tumorigenesis. We propose that the HCV core protein cooperates with STAT3, which leads to cellular transformation.

Clearance of HCV improves insulin resistance, beta-cell function, and hepatic expression of insulin receptor substrate 1 and 2.

OBJECTIVES:Hepatitis C virus (HCV) infection is linked to greater insulin resistance. Although HCV itself is a candidate for the development of insulin resistance, the effects of antiviral treatment on impaired glucose metabolism remain unclear. The aim of this study is to examine the effects of clearance of HCV on insulin resistance, beta-cell function, and hepatic expression of insulin receptor substrate (IRS)1/2, central molecules for insulin signaling.METHODS:We analyzed 89 biopsy-proven patients with chronic HCV infection. Patients received interferon-α or interferon-α plus ribavirin for 6 months and were classified into three groups at 6 months after the conclusion of antiviral therapy according to their response to antiviral therapy: sustained responders (N = 29), relapsers (N = 12), and nonresponders (N = 48). Insulin resistance and beta-cell function were assessed by the homeostasis model assessment method (HOMA-IR and HOMA-%B, respectively). Hepatic expression of IRS1/2 was evaluated by immunoblotting and immunostaining in 14 sustained responders.RESULTS:In nonresponders and relapsers, there were no significant changes in HOMA-IR and HOMA-%B values after antiviral therapy. On the other hand, in sustained responders, HOMA-IR values significantly decreased to 1.7 ± 0.8 from 3.1 ± 1.1 (P < 0.05) after antiviral therapy. Similarly, HOMA-%B values significantly decreased to 90.6 ± 10.0 from 113.7 ± 15.3 (P < 0.05). Immunoblotting showed a threefold increase in IRS1/2 expression after clearance of HCV. Immunostaining revealed that greater IRS1/2 expression was seen in hepatocytes.CONCLUSIONS:We showed that clearance of HCV improves insulin resistance, beta-cell function, and hepatic IRS1/2 expression.

Microvascular Invasion in Patients with Hepatocellular Carcinoma and Its Predictable Clinicopathological Factors

BackgroundMacroscopic vascular invasion is known to be a poor prognostic factor in hepatocellular carcinoma (HCC). The aim of this study was to determine the outcomes and predictive factors after hepatic resection for HCC with microvascular invasion (MVI).MethodsOne hundred ten patients who underwent curative resection for HCC without macroscopic vascular invasion were included in this retrospective study. The risk factors of these patients for recurrence-free and disease-specific survival were investigated, and the clinicopathological factors predicting the presence of MVI were also determined.ResultsOf the 110 resected specimens, 49 (45%) had evidence of MVI. By univariate analysis, MVI was found to be statistically significantly associated with greater tumor size, gross classification, histological grade, and intrahepatic micrometastasis. Gross classification proved to be the only independent predictive factor for MVI by multiple logistic regression analysis. By multivariate analysis, cirrhosis and MVI were identified as independent risk factors for recurrence-free survival. The 5-year recurrence-free survival rates for patients with and without MVI were 20.8% and 52.6%, respectively. By multivariate analysis, the number of tumors, presence of MVI, and intrahepatic micrometastasis were identified as independent predictors of disease-specific survival. The 5-year disease-specific survival rates for patients with and without MVI were 59.3% and 92.0%, respectively.ConclusionsThe presence of MVI was the most important risk factor affecting recurrence and survival in HCC patients after curative resection. Furthermore, this study showed that gross classification of HCC can be very helpful in predicting the presence of MVI.

Expression and Role of Vascular Endothelial Growth Factor in Liver Regeneration After Partial Hepatectomy in Rats

Vascular endothelial growth factor (VEGF) plays a major role in angiogenesis, which is essential for both healing of injured tissue and proliferation of carcinoma cells. In this study we elucidated the expression and role of VEGF in rat liver regeneration after partial hepatectomy. VEGF expression was mainly detected in periportal hepatocytes and reached a maximal level 48–72 hr after partial hepatectomy by both immunohistochemistry and in situ hybridization. Similarly, immunohistochemistry for Ki-67 showed that the proliferative activity of sinusoidal endothelial cells was highest in the periportal area and reached a maximal level 72 hr after partial hepatectomy. Moreover, neutralization of VEGF significantly inhibited proliferative activity of hepatocytes (p < 0.0001), as well as sinusoidal endothelial cells (p < 0.001), at 48 and 96 hr after partial hepatectomy. Conversely, injection of VEGF significantly promoted proliferative activity of hepatocytes (p < 0.0001) as well as sinusoidal endothelial cells (p < 0.0005) at 48 hr after partial hepatectomy. These results suggest that VEGF promotes proliferation of hepatocytes through reconstruction of liver sinusoids by proliferation of sinusoidal endothelial cells. Furthermore, these data point to a new therapeutic strategy, the use of VEGF and other hepatocyte growth factors in fulminant or severe acute hepatitis.

Luteolin promotes degradation in signal transducer and activator of transcription 3 in human hepatoma cells: an implication for the antitumor potential of flavonoids.

In this study, we have investigated the underlying molecular mechanism for the potent proapoptotic effect of luteolin on human hepatoma cells both in vitro and in vivo, focusing on the signal transducer and activator of transcription 3 (STAT3)/Fas signaling. A clear apoptosis was found in the luteolin-treated HLF hepatoma cells in a time- and dosage-dependent manner. In concert with the caspase-8 activation by luteolin, an enhanced expression in functional Fas/CD95 was identified. Consistent with the increased Fas/CD95 expression, a drastic decrease in the Tyr(705) phosphorylation of STAT3, a known negative regulator of Fas/CD95 transcription, was found within 20 minutes in the luteolin-treated cells, leading to down-regulation in the target gene products of STAT3, such as cyclin D1, survivin, Bcl-xL, and vascular endothelial growth factor. Of interest, the rapid down-regulation in STAT3 was consistent with an accelerated ubiquitin-dependent degradation in the Tyr(705)-phosphorylated STAT3, but not the Ser(727)-phosphorylated one, another regulator of STAT3 activity. The expression level of Ser(727)-phosphorylated STAT3 was gradually decreased by the luteolin treatment, followed by a fast and clear down-regulation in the active forms of CDK5, which can phosphorylate STAT3 at Ser(727). An overexpression in STAT3 led to resistance to luteolin, suggesting that STAT3 was a critical target of luteolin. In nude mice with xenografted tumors using HAK-1B hepatoma cells, luteolin significantly inhibited the growth of the tumors in a dosage-dependent manner. These data suggested that luteolin targeted STAT3 through dual pathways-the ubiquitin-dependent degradation in Tyr(705)-phosphorylated STAT3 and the gradual down-regulation in Ser(727)-phosphorylated STAT3 through inactivation of CDK5, thereby triggering apoptosis via up-regulation in Fas/CD95.