加藤 直也

BACKGROUND: Impaired esophageal mucosal integrity plays a role in causing symptoms of gastroesophageal reflux disease (GERD). Recently, the assessment of esophageal baseline impedance (BI) using the multichannel intraluminal impedance-pH (MII-pH) test was suggested as a surrogate technique for the study of esophageal mucosal integrity and was reported to be useful in distinguishing GERD from non-GERD. However, measuring BI requires a 24-h testing period, is complicated, and causes considerable patient discomfort. SUMMARY: Recently, endoscopy-guided catheters that can measure mucosal impedance (MI) and mucosal admittance (MA), which is the inverse of impedance, were developed, and their usefulness in measuring MI and MA for the diagnosis of GERD has been reported. In these studies, esophageal MI values were significantly lower in patients with GERD than in those without GERD. In contrast, esophageal MA was significantly higher in patients with GERD than in those without. Furthermore, we reported that MA is inversely correlated with BI and correlated with acid exposure time. Key Messages: Endoscopy-guided real-time measurement of MI and MA may allow the estimation of mucosal integrity and may be a useful diagnostic tool for patients with GERD in a manner similar to 24-h MII-pH monitoring.

BACKGROUND/AIMS: Endoscopic balloon dilatation (EBD) is an alternative to surgery for strictures in patients with Crohn's disease (CD). The aim of the present study was to clarify the efficacy and safety of EBD for strictures in patients with CD. METHODS: Twenty-six patients with CD who underwent EBD for strictures from August 2008 to November 2015 were followed up after dilatation. Short-term success was defined as the disappearance of obstructive symptoms after technically adequate dilatation was achieved. The short-term success rate of EBD, safety profile of EBD, and cumulative surgery-free and redilatation-free rates were analyzed. RESULTS: Sixty-five EBDs were performed for CD patients in the follow-up period. The short-term success rate was 100% (26/26), and no complications were encountered during this study. Two (7.7%) patients underwent surgery during the observation period. The cumulative surgery-free rate after the initial EBD was 90.3% at both 2 and 3 years. The cumulative redilatation-free rate after the initial EBD was 52.1% at 2 years and 39.1% at 3 years. CONCLUSION: EBD for strictures secondary to CD provides not only short-term success but also long-term efficacy. Although a high redilatation rate is one of the clinical problems of this procedure, EBD is an effective therapy for avoiding intestinal recession in CD -stricture.

BACKGROUND: In Western countries, most patients with primary sclerosing cholangitis (PSC) have concurrent ulcerative colitis (UC). The number of patients with UC in East Asia has increased markedly over the past two decades. However, current clinical features of PSC and of PSC associated with UC (PSC-UC) have not yet been clarified in East Asia, particularly in Japan. We aimed to reveal the clinical courses and associations with UC in Japanese patients with PSC from the mutual viewpoint of PSC and UC. METHODS: We retrospectively retrieved medical records of patients with PSC (69) and UC (1242) who were diagnosed at Chiba University Hospital between June 1991 and August 2017. RESULTS: In the present cohort, 37 patients had PSC-UC; the cumulative risks of PSC in patients with UC and of UC in patients with PSC were 3.0% and 53.6%, respectively. We confirmed similar distinctive results by a Japanese nationwide survey, noting that younger patients with PSC had a notably high possibility of association with UC. From the viewpoint of the UC cohort, the occurrence of right-sided disease was significantly higher in patients with PSC-UC than in those with UC (16.2% vs. 4.2%, P = 0.003). Pancolitis was more commonly observed in PSC-UC, and proctits/left-sided colitis was less commonly found in patients with UC. The number of patients with young-onset PSC-UC may be increasing similar to an increase in patients with UC in Japan. CONCLUSIONS: In our cohort, the comorbidity rate of PSC-UC was higher than that obtained in previous reports. The incidence of PSC-UC and UC may increase in the future in East Asia, particularly in Japan.

Background: Sustained virologic response (SVR) by interferon and interferon-free treatment can results in the reduction of advanced liver fibrosis and the occurrence of hepatocellular carcinoma in patients infected with hepatitis C virus (HCV). Recent interferon-free treatment for HCV shortens the duration of treatment and leads to higher SVR rates, without any serious adverse events. However, it is important to retreat patients who have had treatment-failure with HCV non-structural protein 5A (NS5A) inhibitor-including regimens. Combination of sofosbuvir and ledipasvir only leads to approximately 100% SVR rates in HCV genotype (GT1b), NS5A inhibitornaïve patients in Japan. This combination is not an indication for severe renal disease or heart disease, and these patients should be treated or retreated with a different regimen. Case summary: Retreatment with HCV non-structural protein 3/4A inhibitor, grazoprevir, and HCV NS5A inhibitor, elbasvir, successfully eradicated HCV RNA in three patients with HCV genotype 1b infection who discontinued prior interferon-free treatments including HCV NS5A inhibitors due to adverse events within 2 weeks. Conclusion: Retreatment with the 12-week combination regimen of grazoprevir and elbasvir is effective for HCV GT1b patients who discontinue the HCV NS5A inhibitor-including regimens within 2 weeks. The treatment response may be related to the short duration of initial treatment, which did not produce treatment-emergent RASs.

Background: Interferon-free treatment results in higher sustained virologic response (SVR) rates, with no serious adverse events in hepatitis C virus (HCV)- infected patients. However, in some patients with treatment-failure in HCV NS5A inhibitor-including interferon-free regimens, the treatment-emergent HCV NS5A resistance-associated variants (RAVs), which are resistant to interferon-free retreatment including HCV NS5A inhibitors, are observed. In HCV-infected Japanese patients with daclatasvir and asunaprevir treatment failure, retreatment with sofosbuvir and ledipasvir could lead to only ~70% SVR rates. Case summary: Three HCV genotype (GT)-1b-infected cirrhotic patients who discontinued the combination of daclatasvir and asunaprevir due to adverse drug reactions within 4 weeks retreatment with sofosbuvir and ledipasvir combination could result in SVR in these patients without RAVs. One HCV GT-1b-infected cirrhotic patient who discontinued the combination of daclatasvir and asunaprevir due to viral breakthrough at week 10 retreatment with sofosbuvir and ledipasvir combination for this patient with the treatment-emergent HCV NS5A RAV-Y93H resulted in viral relapse at week 4 after the end of the treatment. Conclusion: Retreatment with sofosbuvir and ledipasvir is effective for HCV GT- 1b patients who discontinue the combination of daclatasvir and asunaprevir within 4 weeks. The treatment response should be related to the existence of treatmentemergent HCV NS5A RAVs, but may not be related to the short duration of treatment.

A 40-year-old Japanese man with a history of kidney transplantation was admitted to our hospital for the detailed evaluation of elevated serum hyperammonia level, hepatic encephalopathy and vascular abnormality detected on computed tomography images. Ultrasonography revealed a patent ductus venosus, which was confirmed by venous catheterization. Balloon occlusion of the ductus venosus resulted in the congestion of extrahepatic portal flow with no demonstration of intrahepatic portal vein branches. He was diagnosed as congenital absence of the portal vein (type I), and percutaneous liver biopsy provided histological proof of primary biliary cholangitis (Scheuer’s classification, stage 2 Nakamuma’s classification, stage 3). This is a very rare adult case of congenital portosystemic shunt, and liver transplantation may be recommended in the future.

The aim of this study was to characterize the treatment response and serious adverse events of ledipasvir plus sofosbuvir therapies in Japanese patients infected with hepatitis C virus (HCV) genotype 1 (GT1). This retrospective study analyzed 240 Japanese HCV GT1 patients treated for 12 weeks with 90 mg of ledipasvir plus 400 mg of sofosbuvir daily. Sustained virological response at 12 weeks post-treatment (SVR12) was achieved in 236 of 240 (98.3%) patients. Among treatment-naive patients, SVR12 was achieved in 136 of 138 (98.6%) patients, and among treatment-experienced patients, SVR12 was achieved in 100 of 102 (98.0%) patients. In patients previously treated with peginterferon plus ribavirin with various HCV NS3/4A inhibitors, 100% SVR rates (25/25) were achieved. Two relapsers had HCV NS5A resistance-associated variants (RAVs), but no HCV NS5B-S282 was observed after they relapsed. We experienced two patients with cardiac events during treatment. In conclusion, combination of ledipasvir plus sofosbuvir for 12 weeks is a potential therapy for HCV GT1 patients. Caution is needed for HCV NS5A RAVs, which were selected by HCV NS5A inhibitors and cardiac adverse events.

A patient with hepatocellular carcinoma (HCC) with a history of two hepatectomies showed a recurrence of HCC and lung metastasis. The patient subsequently started administration of sorafenib however, 18 weeks later, he experienced upper abdominal pain and was referred to our hospital. Contrast-enhanced ultrasonography and computed tomography showed an arterial aneurysm rupture. Atthe same site,ahepatic arteriovenous fistula of the hepatic artery and a middle hepatic vein branch was formed. An emergency angiography and transcatheter arterial embolization using a gelatin sponge were performed. The hepatic arterial aneurysm did not recur. However, 16 months post discharge, the patient died because of progression of HCC. In patients with a history of HCC treatment, care should be taken for the occurrence of a hepatic arterial aneurysm. At the time of rupture, rapid and accurate image diagnosis, including identification of the relationship with surrounding blood vessels, should be performed before treatment.

Aim: The PNPLA3 rs738409 C>G polymorphism (encoding for I148M) has recently been identified as a susceptibility factor for steatosis-mediated liver damage. We evaluated the influence of this polymorphism on hepatocarcinogenesis in patients with chronic hepatitis C (CHC) virus infection. Methods: We genotyped the rs738409 single nucleotide polymorphism in 358 hepatitis C-associated hepatocellular carcinoma (HCC) patients and correlated the age at onset of HCC and the interval between hepatitis C virus (HCV) infection and the development of HCC in patients with each genotype. Results: The frequencies of CC, CG and GG genotypes were 27.9% (100/358), 49.2% (176/358) and 22.9% (82/358), respectively, and were in Hardy-Weinberg equilibrium. The median age at onset of HCC for the GG genotype was significantly younger compared to for non-GG genotypes (67.81 vs 69.87 years, P < 0.001), and the median interval between HCV infection and the development of HCC was significantly shorter in patients with the GG genotype (39.96 vs 40.85 years, P = 0.008). PNPLA3 GG genotype was also associated with a higher aspartate aminotransferase level (69.5 vs 59.0 IU/L, P = 0.02), lower prothrombin time (73.0% vs 78.0%, P = 0.008) and a higher prevalence of histological steatosis (40.0% vs. 22.2%, P = 0.01) at the time of HCC onset. Conclusion: The PNPLA3 genotype GG may be associated with accelerated hepatocarcinogenesis in CHC patients through increased steatosis in the liver.

BACKGROUND: IL28B polymorphisms were shown to be associated with a response to peg-interferon-based treatment in chronic hepatitis C (CHC) and spontaneous clearance. However, little is known about how this polymorphism affects the course of CHC, including the development of hepatocellular carcinoma (HCC). We evaluated the influence of IL28B polymorphisms on hepatocarcinogenesis in CHC patients. METHODS: We genotyped the rs8099917 single-nucleotide polymorphism in 351 hepatitis C-associated HCC patients without history of IFN-based treatment, and correlated the age at onset of HCC in patients with each genotype. RESULTS: Frequencies of TT, TG, and GG genotypes were 74.3 % (261/351), 24.8 % (87/351), and 0.9 % (3/351), respectively. The mean ages at onset of HCC for TT, TG, and GG genotypes were 69.9, 67.5 and 66.8, respectively. In multivariate analysis, IL28B minor allele (TG and GG genotypes) was an independent risk factor for younger age at onset of HCC (P = 0.02) in males (P < 0.001) with higher body mass index (BMI; P = 0.009). The IL28B minor allele was also associated with a lower probability of having aspartate aminotransferase-to-platelet ratio index (APRI) >1.5 (minor vs. major, 46.7 vs. 58.6 %; P = 0.01), lower AST (69.1 vs. 77.7 IU/L, P = 0.02), lower ALT (67.8 vs. 80.9 IU/L, P = 0.002), higher platelet count (12.8 vs. 11.2 × 10(4)/μL, P = 0.002), and higher prothrombin time (79.3 vs. 75.4 %, P = 0.002). CONCLUSIONS: The IL28B minor allele was associated with lower inflammatory activity and less progressed fibrosis of the liver; however, it constituted a risk factor for younger-age onset of HCC in CHC patients.

Background & Aims: IL28B polymorphisms were shown to be strongly associated with the response to interferon therapy in chronic hepatitis C (CHC) and spontaneous viral clearance. However, little is known about how these polymorphisms affect the natural course of the disease. Thus, we conducted the present meta-analysis to assess the impact of IL28B polymorphisms on disease progression. Methods: A literature search was conducted using MEDLINE, EMBASE, and the Cochrane Library. Integrated odds ratios (OR) were calculated with a fixed-effects or random-effects model based on heterogeneity analyses. Results: We identified 28 studies that included 10,024 patients. The pooled results indicated that the rs12979860 genotype CC was significantly associated (vs. genotype CT/TT; OR, 1.122; 95% CI, 1.003-1.254; P = 0.044), and that the rs8099917 genotype TT tended to be (vs. genotype TG/GG; OR, 1.126; 95% CI, 0.988-1.284; P = 0.076) associated, with an increased possibility of severe fibrosis. Both rs12979860 CC (vs. CT/TT; OR, 1.288; 95% CI, 1.050-1.581; P = 0.015) and rs8099917 TT (vs. TG/GG; OR, 1.324; 95% CI, 1.110-1.579; P = 0.002) were significantly associated with a higher possibility of severe inflammation activity. Rs8099917 TT was also significantly associated with a lower possibility of severe steatosis (vs. TG/GG; OR, 0.580; 95% CI, 0.351-0.959; P = 0.034), whereas rs12979860 CC was not associated with hepatic steatosis (vs. CT/TT; OR, 1.062; 95% CI, 0.415-2.717; P = 0.901). Conclusions: IL28B polymorphisms appeared to modify the natural course of disease in patients with CHC. Disease progression seems to be promoted in patients with the rs12979860 CC and rs8099917 TT genotypes.

Background: Ethanol injection is the best-known image-guided percutaneous ablation for hepatocellular carcinoma (HCC) and a well-tolerated, inexpensive procedure with few adverse effects. However, there have been few reports on its long-term results. Aims: We report a 20-year consecutive case series at a tertiary referral centre. Methods: We performed 2147 ethanol injection treatments on 685 primary HCC patients and analysed a collected database. Results: Final computed tomography demonstrated complete ablation of treated tumours in 2108 (98.2%) of the 2147 treatments. With a median follow-up of 51.6 months, 5-, 10- and 20-year survival rates were 49.0% [95% confidence interval (CI) = 45.3-53.0%], 17.9% (95% CI = 15.0-21.2%) and 7.2% (95% CI = 4..5-11.5%) respectively. Multivariate analysis demonstrated that age, Child-Pugh class, tumour size, tumour number and serum alpha-fetoprotein level were significant prognostic factors for survival. Five-, 10- and 20-year local tumour progression rates were 18.2% (95% CI = 15.0-21.4%), 18.4% (95% CI = 15.2-21.6%) and 18.4% (95% CI = 15.2-21.6%) respectively. Five-, 10- and 20-year distant recurrence rates were 53.5% (95% CI = 49.4-57.7%), 60.4 (95% CI = 56.3-64.5%) and 60.8% (95% CI = 56.7-64.9%) respectively. There were 45 complications (2.1%) and two deaths (0.09%). Conclusions: Ethanol injection was potentially curative for HCC, resulting in survival for more than 20 years. This study suggests that new ablation therapies will achieve similar or even better long-term results in HCC. © 2012 John Wiley &amp Sons A/S.

Purpose Development of improved protocols for differentiating induced pluripotent stem (iPS) cells into hepatic cells is an important step toward their use in the field of hepatology. Specifically, the number of different cytokines should be reduced to limit undesired effects and to reduce the cost of the process. In this report, we describe a simple method for directing human iPS cells to differentiate into hepatic cells using only two cytokines and a short incubation time. Methods A two-step protocol for differentiating iPS cells into hepatic cells was developed. A high dose of activin A was applied for 3 days to induce definitive endoderm formation. Subsequently, cells were treated with hepatocyte growth factor (HGF) for 5 days to generate hepatic cells. Differentiation was confirmed by immunostaining for differentiation markers. Albumin mRNA levels in differentiated hepatic cells generated using a previously tested three-step protocol that uses activin A, fibroblast growth factor (FGF)/bone morphogenetic protein (BMP), and HGF, and our new protocol were compared to determine the efficiency of differentiation. Results Our two-step protocol induced the differentiation of iPS cells into hepatic cells and required a shorter differentiation period than the previous three-step protocol. The differentiation efficiencies of the two protocols were comparable and the induced hepatic cells were functional. Conclusions Developing efficient induction and culture methods to generate more highly matured hepatocytes is essential for regenerative cell-based therapies. Our protocol provides a simple, cost-effective, and time-saving approach for generating hepatic cells from iPS cells.

Chronic hepatitis C virus (HCV) infection often results in hepatocellular carcinoma (HCC). Previous studies have shown that there might be some characteristic mutations in the core region of HCV related to HCC. Thus, we downloaded and analyzed HCV genotype 1b core gene sequences from HCV databases online to identify them. Based on the information of the sequences, 63 from patients with HCC and 188 from non-HCC were enrolled into our analysis. Then, the nucleotides at each position were compared by chi(2)-test between the two groups, and 24 polymorphisms were found to be associated with HCC. Further analysis of these 24 polymorphisms by logistic regression indicated that eight were significantly related to the increased HCC risk: A028C, G209A, C219U/A, U264C, A271C/U, C378U/A, G435A/C, and G481A. Moreover, U303C/A was associated with the decreased HCC risk. These mutations could bring about four amino acid substitutions: K10Q, R70Q, M91L, and G161S. In conclusion, eight characteristic mutations in the HCV-1b core gene related to the occurrence of HCC were identified. The structural and functional alterations of core protein due to these mutations and the relationship with the occurrence of HCC need to be further studied.

Ultrasonography is the most frequently used modality in surveillance for HCC among patients with chronic hepatitis C. However, the optimal surveillance interval is still controversial and the usefulness of supplementary tumor marker determination has not been confirmed. A total of 243 cases of naive HCC were detected among 1,431 patients with chronic hepatitis C under outpatient-based surveillance. The mode of HCC detection, including ultrasound surveillance interval, was retrospectively examined and the relation between the interval and detected tumor size was analyzed. Tumor volume doubling time was estimated from exponential increase in serum tumor marker levels when applicable. HCC was first detected by ultrasonography in 221 patients. Ultrasound surveillance interval, ranging between 2 and 8 months, was not correlated with the size of tumor at detection. Patients with cirrhosis were likely to be surveyed at shorter intervals. The size of tumor exceeded 30 mm only in three (1.4%) cases. They were all positive for a biomarker and the estimated tumor doubling time was short. In 14 cases, HCC was first detected by CT indicated by abnormal rise in tumor marker levels despite negative ultrasound findings. In the remaining eight cases, ultrasonography had been replaced by CT as surveillance modality because of excessive obesity or coarseness of liver parenchyma. Ultrasound surveillance at 6-month intervals was appropriate in general for the detection of HCC at a size smaller than 30 mm. However, in patient with established cirrhosis, more frequent screening would be needed to detect tumors of the same size.

Liver stiffness, noninvasively measured by transient elastography, correlates well with liver fibrosis stage. The aim of this prospective study was to evaluate the liver stiffness measurement (LSM) as a predictor of hepatocellular carcinoma (HCC) development among patients with chronic hepatitis C. Between December 2004 and June 2005, a total of 984 HCV-RNA positive patients, without HCC or a past history of it, visited the University of Tokyo Hospital. LSM was performed successfully in 866 patients, who gave informed consent. During the follow-up period (mean, 3.0 years), HCC developed in 77 patients (2.9% per 1 person-year). The cumulative incidence rates of HCC at 1, 2, and 3 years were 2.4%, 6.0%, and 8.9%, respectively. Adjusting for other significant factors for HCC development, patients with higher LSM were revealed to be at a significantly higher risk, with a hazard ratio, as compared to LSM &lt;= 10 kPa, of 16.7 (95% confidence interval [CI], 3.71-75.2; P &lt; 0.001) when LSM 10.1-15 kPa, 20.9 (95% CI, 4.43-98.8; P &lt; 0.001) when LSM 15.1-20 kPa, 25.6 (95%CI, 5.21-126.1; P &lt; 0.001) when LSM 20.1-25 kPa, and 45.5 (95% CI, 9.75-212.3; P &lt; 0.001) when LSM &gt;25 kPa. Conclusions. This prospective study has shown the association between LSM and the risk of HCC development in patients with hepatitis C. The utility of LSM is not limited to a surrogate for liver biopsy but can be applied as an indicator of the wide range of the risk of HCC development. (HEPATOLOGY 2009;49:1954-1961.)

Objective: The degree of liver fibrosis is the strongest indicator of risk for hepatocellular carcinoma (HCC) development. Recently developed transient elastography (Fibroscan, Echosens, France) noninvasively measures liver stiffness, and the correlation between the stiffness and liver fibrosis stage has been validated. In this cross-sectional study, we investigated the relationship between liver stiffness and HCC presence. Methods: Liver stiffness was measured in chronic hepatitis C patients (85 with HCC and 180 without) by transient elastography. Multivariate logistic regression was applied to assess the association with HCC presence. We computed the receiver operating characteristics (ROC) curves concerning the prediction of HCC presence and compared the areas under ROC curve (AUROC). We also calculated stratum-specific likelihood ratios (SSLR). Results: Multivariate analysis showed that HCC presence was significantly associated with liver stiffness (P &lt; 0.0001) along with age, male, and alpha-fetoprotein concentration. AUROC was 0.805, 0.741, 0.714, 0.673, 0.670, and 0.654 for liver stiffness, alpha-fetoprotein, albumin, prothrombin activity, AST-platelet ratio index, and platelet count, respectively. Other parameters showed smaller AUROC. SSLR for HCC presence by liver stiffness was 0.22 (95% confidence interval: 0.11-0.42) in &lt; 10 kPa, 0.73 (0.39 to 1.39) in 10.1 to 15 kPa, 1.30 (0.80 to 2.12) in 15.1 to 25 kPa, and 5.0 (2.96 to 8.47) in &gt; 25 kPa. Conclusions: Liver stiffness measured by transient elastography is useful in demarcating chronic hepatitis C patients at a high risk for HCC, who require frequent check-up by imaging examinations.

Background & Aims: it is not fully elucidated whether obesity enhances hepatocarcinogenesis in patients with chronic hepatitis C. The aim of this study was to investigate the relationship between body weight and risk of hepatocarcinogenesis in chronic hepatitis C patients. Methods: We enrolled 1431 patients with chronic hepatitis C who visited our liver clinic between 1994 and 2004, excluding those with hepatocellular carcinoma (HCC) at their visit or with a previous history of HCC. They were divided into 4 groups according to body mass index (BMI): underweight (&lt;= 18.5 kg/m(2), N = 112); normal (18.5 to less than 25 kg/m(2), N = 1023); overweight (25 to less than 30 kg/m(2), N = 265); and obese (&gt; 30 kg/m(2), N = 3 1). We assessed the impact of obesity on the hepatocarcinogenesis adjusted by multivariate Cox proportional hazard regression with other risk factors found significant in univariate analysis. Results: During the follow-up period (mean, 6.1 y), HCC developed in 340 patients, showing cumulative incidence rates of 10.5%, 19.7%, and 36.8% at 3, 5, and 10 years, respectively. The incidence differed significantly among the BMI groups (P=.007). Adjusting for other significant factors, overweight and obesity were shown to be an independent risk factor of HCC, with a hazard ratio of 1.86 (95% confidence interval, 1.09-3.16; P =.022) and 3.10 (95% confidence interval, 1.41-6.81; P =.005) as compared with the underweight patients. Conclusions: The risk of HCC in patients with chronic hepatitis C increases in proportion to BMI in a wide range of its values, from underweight to obese.

Innate immunity is part of the antiviral response. Interferon (IFN)-beta plays a leading role in this system. To investigate the influence of hepatitis C virus (HCV) on innate immunity, we examined the effect of viral proteins on IFN-beta induction. HepG2 cells were co-transfected with plasmids for seven HCV proteins (core protein, NS2, NS3, NS4A, NS4B, NS5A, and NS5B) and the IFN-beta promoter luciferase. Toll-like receptor (TLR) 3 and Toll/IL-1 receptor domain-containing adapter inducing IFN-beta (TRIF) play key roles in dsRNA-mediated activation of interferon regulatory factor (IRF)-3 and IFN-beta; therefore, the participation of TLR3/TRIF in NS5B-mediated IFN induction was examined. Among seven HCV proteins, only NS5B, a viral RNA-dependent RNA polymerase (RdRp), activated the IFN-beta promoter. However, mutant NS5B without RdRp activity or template/primer association did not activate the IFN-beta promoter. Activation of the IFN-beta promoter by NS5B required the positive regulatory domain III, a binding sequence for IRF-3. Moreover, IRF-3 was phosphorylated by NS5B. Both inhibition of TLR3 expression by small interfering RNA and expression of the dominant negative form of TRIF significantly reduced NS5B-induced activation of IFN-beta. Of the six other HCV proteins, NS4A, NS4B, and NS5A efficiently inhibited this activation. HCV NS5B is a potent activator of the host innate immune system, possibly through TLR3/TRIF and synthesis of dsRNA. Meanwhile, NS4A, NS4B, and NS5A block IFN-beta induction by NS5B, which may contribute toward the persistence of this virus.

Background/Aims: Only limited patients with hepatoma. benefit from chemotherapy without a clear explanation. We aimed to identify genes associated with chemosensitivity using transcriptional profiles. Methodology: In 8 hepatoma cells (HLE, HLF, Huh7, Hep3B, PLC/PRF/5, SK-Hep1, Huh6, and HepG2) transcriptional profiles were obtained using cDNA microarray including 2,300 genes. Chemosensitivities to 8 anticancer drugs (nimustine, mitomycin C, cisplatin, carboplatin, doxorubicin, epirubicin, mitoxantrone, and 5-fluorouracil) were measured by obtaining 50% growth inhibitory concentrations (GI50) using MTT assay. Genes having drug-specific association with chemosensitivity were selected. Results: Up-regulation of topoisomerase II beta was associated with chemo-resistance, the target of doxorubicin. Platinum-specific resistance was associated with superoxide dismutase 2 expression. Antigen peptide transporter I expression correlated with nimustine and mitoxantrone-specific susceptibility. These results were verified by semi-quantitative RT-PCR. Drug inactivators reported in non-liver cancers such as multidrug transporters and drug metabolizers showed less diversity of chemosensitivity in hepatoma cells. Conclusions: To evaluate these gene expressions may be useful to select anticancer drugs, and possibly to consider new therapeutic target to modify drug action.

PURPOSE: A single nucleotide polymorphism (SNP) in the promoter region of MDM2 gene, SNP309, has recently been shown to be associated with accelerated tumor formation in both hereditary and sporadic cancers in humans. However, the association of SNP309 with hepatocellular carcinoma is unknown. We evaluated the association of SNP309 with the risk of hepatocellular carcinoma development among Japanese patients with chronic hepatitis C virus infection. EXPERIMENTAL DESIGN: We genotyped the SNP309 at the MDM2 promoter in 435 Japanese patients with chronic hepatitis C virus infection, including 187 patients with hepatocellular carcinoma and 48 healthy subjects, using a fluorogenic PCR. Presence of SNP was also confirmed by direct sequencing of the MDM2 promoter region. RESULTS: The proportion of G/G genotype of the SNP309 in patients with hepatocellular carcinoma (33%) was significantly higher than that in patients without hepatocellular carcinoma (23%), with an odds ratio (95% confidence interval) of 2.28 (1.30-3.98). A multivariate analysis revealed that MDM2 SNP309 (G/G versus T/T), age >60 years, male gender, presence of cirrhosis, serum alpha-fetoprotein >20 mug/L, and serum albumin <3.2 g/dL were independently associated with the hepatocellular carcinoma development at odds ratio of 2.27, 2.46, 3.08, 4.15, 4.87, and 6.33, respectively. CONCLUSIONS: The MDM2 promoter SNP309 is associated with the presence of hepatocellular carcinoma in Japanese patients with chronic hepatitis C.

AIM: To determine fibrosis progression and hepatocellular carcinoma (HCC), using simultaneous gene expression analysis. METHODS: Total RNA samples were extracted from liver biopsies from 19 patients with hepatitis C virus (HCV) infection and 3 patients without HCV infection. Among the 19 HCV-infected patients, 7 and 12 patients had grade F1-2 and F3-4 fibrosis, respectively. Of the 12 patients with F3-4 fibrosis, 8 had HCC. Gene expression in the liver samples was determined using an oligonucleotide microarray. The following comparisons were performed: normal livers vs HCV-infected livers; F1-2 vs F3-4; and F3-4 with HCC vs F3-4 without HCC. Genes that were differentially expressed between these groups were identified based on signal-to-noise ratios. RESULTS: In the HCV-infected livers, genes involved in immune responses were highly expressed. Expression levels of genes for plasma proteins and drug-metabolizing enzymes were decreased and those of genes involved in the cell cycle and oncogenesis were increased in the F3-4 cases as compared to the F1-2 cases. Among the F3-4 cases, genes involved in carbohydrate metabolism tended to be more highly expressed in patients with HCC than in patients without HCC. CONCLUSION: We identified genes that are associated with fibrosis progression and hepatocarcinogenesis. This information may be used to detect increased carcinogenic potential in the livers of patients with HCV infection. (C) 2005 The WJG Press and Elsevier Inc. All rights reserved.

Background/aim: Cirrhosis in chronic hepatitis C is a major cause of mortality. The components of reported diagnostic indices of cirrhosis based on biochemical markers may be modified by therapies for hepatic inflammation. We aimed to construct index of cirrhosis in patients treated for chronic active hepatitis. Methods: Using sera of consecutive 140 patients with chronic hepatitis C, routine blood tests including fibrosis markers, type IV collagen and procollagen type III peptide (PIIIP), were performed. Diagnosis of cirrhosis was determined by biopsy. Using multivariate analyses, diagnostic indices of cirrhosis were constructed. Results: Fifty-eight patients were diagnosed to have cirrhosis. Platelet count, prothrombin time, and albumin were lower, and type IV collagen and PIIIP were higher in patients with cirrhosis (p &lt; 0.05). There was no difference in aspartate and alanine aminotransferases (AST, ALT) and gamma-glutamyl-transpeptidase (GGT) (p &gt; 0.3). Our diagnostic indices I (prothrombin time and platelet count) and II (prothrombin time and type IV collagen) of cirrhosis showed the area under the ROC curves (AUC) of 0.77 and 0.81, respectively. The index II was relatively superior to the index I. Conclusions: Using combination of type IV collagen and prothrombin time, efficient diagnosis of cirrhosis can be performed in patients with chronic active hepatitis C. (C) 2004 Elsevier B.V. All rights reserved.

The majority of persons with chronic hepatitis C virus (HCV) infection develop liver fibrosis. Transforming growth factor (TGF)-beta1 plays a pivotal role in the pathogenesis of post-inflammatory liver scarring. To clarify the influence of HCV infection on liver fibrosis, a reporter assay was used to investigate the effect of viral proteins on TGF-beta1 expression in human hepatoma cells. Of all HCV proteins investigated (core, E1/E2/p7, NS2, NS3, NS4A, NS4B, NS5A, and NS5B), only the core protein activated the TGF-beta1 promoter and upregulated TGF-beta1 expression measured by an RNase protection assay. Bases -376 to -331 by in the promoter region of TGF-beta1 are responsible for upregulation by HCV core protein, and the nuclear protein that binds to this region increased with the stimulation of HCV core protein. Blocking the mitogen-activated protein kinase pathway prevented upregulation of TGF-beta1 by HCV core protein. The immunological response is supposed to be a major factor to cause the secretion of TGF-beta1 from non-parenchymal cells, but the results suggest that the HCV core protein expression may upregulate directly TGF-beta1 transcription in parenchymal cells and suggest a new paradigm for exacerbation of liver fibrosis by HCV infection.

In the post-genome-sequencing era, full-length cDNA-sequence resources are extremely useful for functional analyses of genes. In addition, comprehensive gene profiling of human tissues at the mRNA level is also useful in understanding the molecular mechanisms of tissue-specific functions and disease pathogenesis. In this study, to obtain a wide variety of full-length cDNA clones derived from digestive tissues, numerous expressed sequence tags were generated from libraries enriched with full-length cDNAs. In total, 13 575 sequences were obtained from three cDNA libraries, which were constructed from tissues and cell lines of human liver, stomach, and pancreas. The integration of overlapping clones categorized the sequences into 5936 clusters (1666, 2746, and 2222 clusters in the liver, stomach, and pancreas, respectively). Of these, 1138 clones were scored as full-length cDNAs. Surprisingly, the redundant clones from all three tissues were assembled to show that only 101 genes (1.7% of the assembled 5936 genes) were shared. These results suggest that functional differences between tissues are probably related to their divergent gene expression profiles, and form a basis for understanding the molecular mechanisms underlying tissue-specific pathogenesis that are expressed in different organs. In addition, the full-length cDNAs obtained in this study should prove useful for future functional analyses of the genes expressed in digestive tissues. © 2003 Elsevier B.V. All rights reserved.

Hepatitis delta virus (HDV) is a naturally occurring satellite of hepatitis B virus (HBV). There are few studies of the effects of the combination of HBV and HDV proteins (HDV antigens [HDAgs]) on intracellular signaling pathways. To understand the influence of HBV and HDV coinfection on hepatocytes, we investigated the effect of HBV proteins and HDAgs on the serum response element (SRE)-dependent pathway. Reporter assays revealed that only HBV X protein (HBx), alone or with the large isoform of HDAg (LHDAg), synergistically activated the SRE-dependent pathway. The effect of HBx and LHDAg on Elk1 or serum response factor (SRF) was examined, because both proteins bind to the SRE. HBx activated the transcriptional ability of Elk1, whereas LHDAg activated the transcriptional ability of SRF. Thus, HBx and LHDAg synergistically activated the SRE-dependent pathway. These results may help us understand clinical phenomena in patients coinfected with HBV and HDV.

Generally, hepatoma is not a chemosensitive tumor, and the mechanism of resistance to anticancer drugs is not fully elucidated. We aimed to comprehensively evaluate the relationship between chemosensitivity and gene expression profile in human hepatoma cells, by using microarray analysis, and analyze the data by constructing relevance networks. In eight hepatoma cell lines (HLE, HLF, Huh7, Hep3B, PLC/PRF/5, SK-Hep1, Huh6, and HepG2), the baseline expression levels of 2300 genes were measured by cDNA microarray. The concentrations of eight anticancer drugs (nimustine, mitomycin C, cisplatin, carboplatin, doxorubicin, epirubicin, mitoxantrone, and 5-fluorouracil) needed for 50% growth inhibition were examined and used as a measure of chemosensitivity. These data were combined and comprehensive pair-wise correlations between gene expression levels and the 50% growth inhibition values were calculated. Significant correlations with significance were used to construct networks of similarity. Fifty-two relations, including 42 genes, were selected. Among them, nearly 20% were various types of transporters, and most of them negatively correlated with chemosensitivity. Transporter associated with antigen processing 1 was associated with resistance to mitoxantrone, consistent with previous reports. Other transporters were not reported previously to associate with chemosensitivity. Resistance to doxorubicin and its analogue, epirubicin, were positively correlated with topoisomerase II beta expression, whereas it negatively correlated with expression of carboxypeptidases A3 and Z. Response to nimustine was associated with expression of superoxide dismutase 2. Relevance networks identified several negative correlations between gene expression and resistance, which were missed by hierarchical clustering. Our results suggested the necessity of systematically evaluating the transporting systems that may play a major role in resistance in hepatoma. This may provide useful information to modify anticancer drug action in hepatoma.

Hepatitis B virus (HBV) is a hepatotropic virus that causes acute and chronic hepatocellular injury and hepatocellular carcinoma. To clarify how HBV proteins regulate host cellular gene expression, we used our in-house cDNA microarray and HepG2.2.15 cells, which are derived from HepG2 cells and produce all HBV proteins. Of 2304 genes investigated, several genes were differentially expressed in HepG2.2.15 cells compared with HepG2 cells. These genes included insulin-like growth factor II and alpha-fetoprotein, consistent with previous reports. Furthermore, we previously performed similar microarray analyses to clarify the effects of hepatitis C virus (HCV) proteins on host cells, using a HepG2-derivative cell line, which produces all HCV proteins. Using these two microarray results, we compared the differences in cellular gene expression induced by HBV and HCV proteins. The expression of the majority of genes investigated differed only slightly between HBV and HCV protein-producing cells. However, HBV and HCV proteins clearly regulated several genes in a reciprocal manner. Combined, these microarray results shed new light on the effects of HBV proteins on cellular gene expression and on the differences in the pathogenic activities of these two hepatitis viruses.

Hepatitis C virus (HCV) causes a persistent infection, chronic hepatitis, cirrhosis, and hepatocellular carcinoma. To explore the influence of HCV infection on hepatocytes, the effects of HCV proteins on intracellular signal transduction pathways, especially those related to apoptosis, fibrosis, and cell growth, were investigated. The effects of nine HCV proteins (core, NS2, NS3, NS4A, NS4B, NS5A, and NS5B) on the CRE-, SRE-, NFB-, AP-1-, SRF-, ISRE-, HSE-, GRE-, and p53-associated pathways were investigated by use of a reporter assay. The effects of core protein on apoptosis were examined by DNA laddering and Western blotting after induction of apoptosis by Fas stimulation. The possible mechanisms of anti-apoptotic effects of core protein were investigated by RNase protection assay and a reporter assay. The effects of HCV proteins on TGF beta production were determined by a reporter assay. Among seven HCV proteins investigated, core protein had the strongest influence on intracellular signaling, especially for the SRE-, AP-1-, NFkappaB-, and p53-associated pathways. Core protein promoted Bcl-x(L) expression through the mitogen-activated protein kinase (MAPK) pathway and inhibited apoptosis. Among HCV proteins, only core protein caused TGF beta promoter activity through the MAPK pathway. From these results, core protein was considered to regulate cell growth exquisitely in hepatocytes, inhibit apoptosis, and promote liver fibrosis directly without any inflammation or the mediation of any other cells. These functions may reflect the direct action of HCV proteins on the intracellular signal transduction pathways related to chronic hepatitis pathogenesis.

Hepatitis C virus (HCV) infection is a major risk factor for developing hepatocellular carcinoma (HCC), a life-threatening sequel. However, the factors that affect disease progression to HCC have not been thoroughly elucidated. Genetic polymorphisms in proinflammatory cytokines, the interleukin 1 (IL-1) family (IL-1beta and IL-1ra) and tumor necrosis factor-alpha (TNF-alpha), were studied in 274 Japanese patients with chronic HCV infection and 55 healthy individuals using standard polymerase chain reaction-based genotyping techniques. The association between these polymorphisms and disease status was evaluated while controlling for confounding clinical variables. The proportion of patients with HCC in the IL-1beta-31 T/T (55%, odds ratio to C/C was 2.63, P =.009) genotype was higher than in the T/C (44%, odds ratio to C/C was 1.64, P =.149) and C/C genotypes (35%). The IL-1beta-31 and -511 loci were in near complete linkage disequilibrium, and the IL-1beta-511/-31 haplotype C-T was significantly associated with the presence of HCC (odds ratio of 1.5 1, P =.02). Polymorphisms in the TNF-alpha gene were not associated with disease. A multivariate analysis revealed that the IL-1beta-31 T/T genotype, alpha-fetoprotein &gt;20 mug/L, presence of cirrhosis, male sex, and age &gt; 60 years were associated with the presence of HCC at odds ratios of 3.73 (T/T vs. C/C), 4.12, 4.03, 3.89, and 3.27, respectively. In conclusion, the IL-1beta-31 genotype T/T or the IL-1beta-511/-31 haplotype C-T is associated with the presence of HCC in Japanese patients with chronic HCV infection.

Previous studies indicated that hepatitis C virus core protein influences cellular apoptosis. However, the precise mechanisms of the effects are not fully understood. Therefore, in this study, we examined the mechanisms of the effects on cell apoptosis by core protein, using transiently transfected and magnetically collected core-producing HepG2 cells. First, to elucidate the target site of core protein in the apoptotic pathway, we examined the activation of caspases after anti-Fas antibody stimulation. Core protein inhibited the apoptotic cascade downstream from caspase 8 and upstream from caspase 3. Next, to clarify more direct mechanisms of this effect, mRNA levels of several bcl-2-related genes were examined. An RNase protection assay showed that the mRNA of bcl-xl increased in the core-producing cells. We showed that this increase was mediated by the enhancement of bcl-x promoter activity by core protein through an extracellular-regulated kinase pathway. These results suggest that core protein inhibits apoptosis at the mitochondria level through augmentation of Bcl-x expression, resulting in an inhibition of caspase 3 activation. (C) 2002 Elsevier Science (USA).

Background. The prognosis of patients with advanced hepatoma is grim. Although chemotherapy is adapted to such patients, the efficacy is low and the outcome cannot be predicted before therapy. In this study, we aimed to identify genes associated with sensitivity to 5-fluorouracil and cisplatin, drugs widely used in treatment, using gene expression profiles. Methods: Gene expression was evaluated in eight human hepatoma cell lines using an in-house cDNA microarray including 2300 known genes. The 50% growth inhibitory concentrations (Gl(50)) of 5-fluorouracil and cisplatin were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and designated as chemosensitivity. Genes with expression ratios associated with Gl(50) were selected using the permutation test. Results: For 5-fluorouracil and cisplatin, 21 and 40 genes, respectively, were selected. From among the genes associated with 5-fluorouracil and cisplatin, several encoding metabolic enzymes were selected. In addition, several genes involved in the cell cycle and transcription were identified. Conclusions: We identified genes that may be associated with sensitivity to 5-fluorouracil and cisplatin. A list of these genes may be useful to elucidate how these drugs work on human hepatoma.

Hepatitis C virus (HCV) causes persistent infection, chronic hepatitis, cirrhosis, and hepatocellular carcinoma. To explore the influence of HCV infection on hepatocytes, the effects of HCV proteins on intracellular signal transduction pathways were investigated. The effects of seven HCV proteins (core, nonstructural [NS]2, NS3, NS4A, NS4B, NS5A, and NS5B) on cyclic AMP response element (CRE)-, serum response element (SRE)-, nuclear factor (NF)-kappaB-, activator protein (AP)-1-, serum response factor (SRF)-, and p53-associated pathways were investigated by use of a reporter assay. The activation of signals by HCV proteins was examined using a reporter plasmid with an interleukin (IL)-8 or p21(waf1) promoter. The possible mechanisms by which HCV proteins activate these pathways were investigated. Among the seven HCV proteins investigated, core protein had the strongest influence on intracellular signaling, especially SRE-, AP-1-, NF-kappaB-, and p53-associated pathways. Core protein activated IL-8 promoter through NF-kappaB and AP-1 and activated p21 promoter having a p53-binding site. Core protein activated the NF-kappaB pathway mainly through IKKbeta and tumor necrosis factor receptor-associated factor 2/6 and augmented p53 function by increasing both p53-DNA binding affinity and transcriptional ability itself. Direct interaction between core protein and the C-terminus of p53 was detected. In addition, the interaction between core protein and human TBP-associated factor 1128, a component of the transcriptional factor complex, was also demonstrated. Core protein may directly promote cell proliferation and induce an inflammatory reaction by activating SRE, AP-1-, and NF-kappaB-associated pathways. On the other hand, core protein could enhance p53 function. These opposing functions may result in exquisitely balancing the proliferation of hepatocytes infected with HCV.

Adequate dosing of interferon (IFN) and its cost-effectiveness for sustained virological response were evaluated in relation to viral load and subtype. Prospective analysis of IFN therapy on 326 patients with chronic hepatitis C free from cirrhosis was performed using 9 or 6 million unit (MU) of IFN for six months daily and/or three times a week. Sustained virological response was achieved in 50-94% of patients with less than or equal to 2 x 10(4) copies/ml (competitive RT-PCR) or &lt;100 x 10(3) copies/ml (Amplicor monitor) of HCV RNA by 468-1206 MU of IFN, but response was only 0-25% of the patients with greater than or equal to 2 x 10(5.5) copies/ml (competitive RT-PCR) or &gt;200 x 10(3) copies/ml (Amplicor monitor), even with 468-1206 MU of IFN. A high sustained rate was demonstrated in patients with 100-200 x 10(3) copies/ml of HCV RNA by 901-1206 MU of IFN, in comparison to that with less than or equal to 900 MU of IFN. Multivariate analysis showed that IFN dose had a significant value for the efficacy of IFN therapy in patients presenting 100-200 x 10(3) copies/ml of HCV RNA. Cost efficacy analysis indicated that it cost approximately $10,000, $26,000, and $50,000-227,000 for one person-viral eradication in the patients with &lt;100, 100-200, and &gt;200 x 10(3) copies/ml, respectively. High-dose IFN is only cost effective in patients with intermediate viral loads, and IFN therapy could be recommended in patients with &lt;200 x 10(3) copies/ml of HCV RNA.

Objective. Haemobilia often results from iatrogenic injury caused by therapeutic procedures. The objective of this study was to evaluate the efficacy of early diagnosis of haemobilia based on ultrasonography in patients with hepatocellular carcinoma undergoing percutaneous ethanol injection. Patients and methods. A combination retrospective and prospective study on the early detection of haemobilia caused by percutaneous ethanol injection was conducted on 365 patients in 1995-1996. The retrospective study reviewed the clinical, laboratory and imaging data of 172 patients who had undergone ethanol injection therapy in 1995. The results showed that ultrasonographic changes in the gallbladder, namely the rapid appearance of echogenic material in the gallbladder lumen, are a useful early sign of haemobilia. Based on the results of the retrospective study, a prospective study on the early detection of haemobilia was carried out in 1996. In the prospective study, percutaneous ethanol injection was halted as soon as haemobilia was detected. Results. The incidence of haemobilia in the prospective group (3.6%) was not different from that in the retrospective group (4.7%). However, the mean duration between percutaneous ethanol injection and diagnosis of haemobilia was only 0.3 ± 0.2 days in the prospective group, compared with 2.8 ± 2.1 days in the retrospective group (P &lt 0.001), and the mean duration of jaundice in the prospective group (4.3 days) was significantly shorter than in the retrospective group (40.0 days) (P &lt 0.05). Conclusion. Early diagnosis of haemobilia based on ultrasonographic findings of the gallbladder lumen effectively reduces the severity of haemobilia-related complications due to immediate interruption of the interventional procedure. (C) 2000 Lippincott Williams and Wilkins.

Radiofrequency ablation is a new therapy for liver neoplasms in which the surrounding area is heated by radiofrequency energy emitted from the inserted electrode, which results in coagulation necrosis of the tumor. We performed radiofrequency ablation using a cool-tip electrode for 61 lesions of hepatocellular carcinoma in 30 cases. Radiofrequency ablation was canceled in no intended cases to treat because of a location of the lesion or others. CT after the treatment demonstrated that all lesions treated by radiofrequency ablation became non-enhanced, showing entire necrosis of the tumor. Percutaneous radiofrequency ablation using a cool-tip electrode, is feasible in almost all cases which can be treated by percutaneous ethanol injection therapy or percutaneous microwave coagulation therapy, and it may reduce the number of treatment sessions and shorten the hospital stay. In the near future, radiofrequency ablation seems to play a major role in the treatment of hepatocellular carcinoma.

Hepatitis C virus (HCV)-RNA status and alanine aminotransferase (ALT) levels determined shortly after interferon (IFN) therapy in patients with chronic hepatitis C do not predict longterm response. To determine the virological sustained response after the completion of IFN therapy, HCV-RNA was measured at the end of treatment and at 3-4 months and 12 months after the completion of therapy in 537 patients with chronic hepatitis C. In 347 patients, HCV-RNA was not detected by polymerase chain reaction (PCR) at the completion of therapy and 175 of these patients (50%) were still PCR negative 12 months later. In contrast, of the 180 patients who were HCV-RNA negative at 3-4 months after completion of therapy, 99% remained negative at 12 months. Normal ALT levels were found in 80, 93 and 95% of patients who were negative for HCV-RNA either at the end of treatment or at 3-4 months and 12 months after the completion of therapy, respectively. Of patients who were HCV-RNA positive, 30, 15 and 20% were found to have normal ALT levels at the same respective time points. To determine a sustained virological response shortly after the completion of therapy, serum HCV-RNA was serially examined in 66 patients negative for HCV-RNA at the end of therapy. Of 31 patients who relapsed, HCV-RNA reappeared in 33, 80, 97 and 100% of patients by 1, 2, 4 and 8 weeks after the completion of therapy. In conclusion, a sustained virological response could be determined with 97 and 99% certainty at 4 weeks and at 3-4 months after the completion of therapy, respectively.

Aims/Background. A recent advancement in Doppler ultrasonography (US) is power Doppler for detecting low-velocity blood flow at the microvascular level with angle independence. The present study was performed to characterize the factors contributing to the power Doppler signals of hepatocellular carcinoma (HCC). Method. Correlation of Doppler signals of HCC in 114 patients with 178 HCC nodules was analyzed in relation to the findings of CT and angiography, tumor characteristics (size, echo pattern, and histological differentiation of tumor), viral markers and severity of liver disease. Results. The sensitivity of power Doppler US was superior to that of CT and angiography (each p &lt 0.05 McNemar's test). The detection rate of power Doppler signal was significantly higher in tumors with diameter ≥ 2 cm (vs &lt 2 cm in diameter), and with low/mixed echo pattern (vs high echo appearance), and with moderately/poorly differentiated HCC (vs well-differentiated HCC). Univariate analysis revealed that echo pattern, tumor size and histological differentiation of HCC in addition to CT and angiographic findings were significant. Multivariate analysis showed that tumor size and differentiation were significant. Conclusion. These results indicate that tumor characteristics play an important role in power Doppler signals and that these could be assessed by the presence or absence of power Doppler signals.

OBJECTIVE. We percutaneously injected ethanol into small vessels afferent to tumor nodules to induce hepatic infarction in areas of tumor caused by hepatocellular carcinoma. CONCLUSION. Percutaneous hepatic infarction therapy holds promise as a new method of treating large hepatocellular carcinoma.

We performed percutaneous microwave coagulation therapy (PMCT) on 89 patients (86 patients with hepatocellular carcinoma, 1 patient with liver metastasis from gastric cancer, 1 patient with liver metastasis from gastric schwannoma, 1 patient with both hepatocellular carcinoma and liver metastasis from colon cancer). CT was performed after PMCT to evaluated the efficacy in all cases. In 78 cases, complete necrosis of the lesions with some safety margin was achieved. In the other 11 cases, PMCT was used only palliatively, but the goal of mass reduction was accomplished. Encountered complications were pleural effusion, hemobilia, subcapsular hematoma, hemoperitoneum, biloma, and others. In conclusion, although PMCT is useful in the treatment of small or middle-size liver tumors, there are various problems to be solved. Improvement of the machine and others is mandatory.

Effects of interferon treatment on hepatitis C virus were examined by investigating the presence of hepatitis C virus ribonucleic acid and anti-hepatitis C virus antibody in 70 patients with non-A, non-B chronic liver diseases. Twenty one patients were treated with three million units of interferon alfa 2a three times a week for 52 weeks, 24 patients were treated similarly for eight weeks, and 25 patients were given a placebo for eight weeks and served as control. Sixty six of 70 patients (94%) were positive for both hepatitis C virus RNA and second generation antihepatitis C virus antibody. Fourteen of 21 (67%) receiving the longterm treatment had a normalised alanine aminotransferase (ALT) activity, and in 12 of these hepatitis C virus ribonucleic acid became undetectable by the end of treatment and remained so during the three year follow up after the treatment. Anti-hepatitis C virus antibody determined by first generation assay became negative in one case at the end of the 52 week treatment, and in four cases at the end of the one year follow up. In contrast, only one of 24 (4%) who received the eight week treatment and only one of 25 (4%) who received the placebo had normalised ALT activities. Hepatitis C virus ribonucleic acid became negative in two patients undergoing shortterm treatment and in none receiving the placebo. Thus, longterm interferon treatment seems effective in clearing hepatitis C virus from serum of patients with chronic liver disease.