Abstract 5100: Expression of the insulin signaling related genes by infection of hepatitis C virus

BACKGROUND: Hepatitis C virus (HCV) induces chronic liver diseases such as chronic hepatitis, cirrhosis, and eventually hepatocellular carcinoma (HCC). Either molecular or clinical studies support a correlation between HCV infection and insulin resistance. Patients with chronic HCV infection have a significantly increased prevalence of type 2 diabetes mellitus compared to controls or HBV-infected patients. The HCV core protein is known to contribute to insulin resistance related steatosis, fibrosis, and carcinogenesis of the liver. Although several hypotheses have been demonstrated, a mechanism of insulin resistance by HCV infection is complex and still unclear. AIM: The aim of this study is to investigate the molecular mechanisms of liver injury by HCV through insulin signaling pathway. MATERIALS AND METHODS: HCV infected cultured cells and transgenic mice expressing HCV core gene were used for this study. A HCV strain JFH-1 replicates efficiently in cultured cells with production of infectious HCV. A transgenic mouse was established by introducing the core gene derived from the HCV genome of genotype 1b. Total RNA was extracted from the cells with and without HCV infection, and the livers of transgenic mice and their littermate wild type mice. The cDNA was synthesized from the RNA then applied to the real-time PCR. The relative amount of the mRNAs of 84 genes related to the insulin receptor and target genes for insulin signaling were compared between the cells or tissues with or without HCV. RESULTS and DISCUSSION: The expression of one of the insulin receptor substrate (IRS) family mRNA was increased in cells infecting HCV, compared to uninfected cells. On the other hand, the Akt mRNA expressed at higher level in the liver of transgenic mouse than that of normal littermate. The IRS family proteins are key mediators in insulin signaling and have been reported to associate with glucose metabolism. The Akt protein kinase is a critical regulator of human physiology that controls an impressive array of diverse cellular functions, including the modulation of growth, survival, proliferation and metabolism. The activation of Akt signaling may induce not only the insulin resistance but also the development of HCCs in the patients with HCV chronic infection. CONCLUSIONS: Our results indicates that the alteration of IRS family and Akt expression by HCV could be predictive for insulin resistance. Since the insulin resistance promotes inflammation and fibrogenesis in the liver, HCV infection leads to the development of liver cirrhosis and HCC by activation of insulin signaling.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5100.

[Cost-effectiveness analysis of chemotherapy with GEM or S-1 for patients with non-resectable pancreatic cancer]

OBJECTIVE

To assess the cost-effectiveness of chemotherapy for patients with non-resectable pancreatic cancer, we compared two regimens containing either gemcitabine (GEM) or S-1.

METHODS

We developed a decision tree that showed the clinical processes of non-resectable pancreatic cancer patients. We calculated the probabilities of endpoint and life months gained (LMG) based on previously reported articles. To estimate the costs, we analyzed medical records of 44 inpatients with non-resectable pancreatic cancer treated with GEM(n=34)or S-1(n=10). Sensitivity analysis was used to check the robustness of the results.

RESULTS

In the GEM group and S-1 group, costs were 1,636,393 and 985,042 yen, and LMG was 6. 0 and 9. 0 months, respectively. Thus, the cost-effectiveness ratio(CER)was calculated to be 272,732 and 109,449 yen/LMG, respectively, and the incremental cost effectiveness ratio (ICER) was -217,117 yen/LMG. The sensitivity analysis showed that the result was definitely robust.

CONCLUSION

Our findings suggest that the markedly cost-effective S-1 regimen could prolong LMG with less cost than the GEM regimen.

Strong CD8(+) T-cell responses against tumor-associated antigens prolong the recurrence-free interval after tumor treatment in patients with hepatocellular carcinoma

AIM

We investigated whether tumor-specific CD8(+) T-cell responses affect tumor-free survival as well as the relationship between CD8(+) T-cell responses against tumor-associated antigens (TAAs) and the clinical course after tumor treatment in patients with hepatocellular carcinoma (HCC).

METHODS

Twenty patients with HCC that were treated by radiofrequency ablation or trans-catheter chemo-embolization (TACE) and in whom HCC was undetectable by ultrasonography, CT, and/or MRI 1 month after treatment were enrolled in the study. Before and after treatment for HCC, analyses of TAA (glypican-3, NY-ESO-1, and MAGE-1)-specific CD8(+) T-cell responses were evaluated with an interferon-gamma enzyme-linked immunospot (ELISpot) assay using peripheral CD8(+) T-cells, monocytes, and 104 types of 20-mer synthetic peptide overlapping by 10 residues and spanning the entirety of the 3 TAAs.

RESULTS

Sixteen out of 20 patients (80%) showed a positive response (> or = 10 TAA-specific cells/10(5) CD8(+) T-cells) before or after treatment. When we performed univariate analysis of prognostic factors for the tumor-free period in the 20 patients, platelet count, prothrombin time, and the number of TAA-specific CD8(+) T-cells after treatment were significant factors (P = 0.027, 0.030, and 0.004, respectively). In multivariate analysis, the magnitude of the TAA-specific CD8(+) T-cell response (> or = 40 TAA-specific cells/10(5) CD8(+) T-cells) was the only significant prognostic factor for a prolonged tumor-free interval (hazard ratio 0.342, P = 0.022).

CONCLUSIONS

Our results suggest that strong TAA-specific CD8(+) T-cell responses suppress the recurrence of HCC. Immunotherapy to induce TAA-specific cytotoxic T lymphocytes by means such as the use of peptide vaccines should be considered for clinical application in patients with HCC after local therapy.

Prolonged treatment with pegylated interferon alpha 2b plus ribavirin improves sustained virological response in chronic hepatitis C genotype 1 patients with late response in a clinical real-life setting in Japan

AIM

This study was conducted to clarify the factors related to sustained virological response (SVR) to pegylated interferon alpha 2b (PEG-IFN) plus ribavirin (RBV) combination therapy administered for 48 weeks in patients with chronic hepatitis C virus (CHCV) and to evaluate the usefulness of prolonged treatment in patients with late virological response (LVR).

METHODS

Of 2257 patients registered at 68 institutions, those with genotype 1 and high viral load were selected to participate in two studies. Study 1 (standard 48-week group, n = 1480) investigated SVR-determining factors in patients who received the treatment for </=52 weeks, whereas study 2 compared SVR rates between patients with LVR who received treatment for either 36-52 weeks (48-week group, n = 223) or 60-76 weeks (72-week group, n = 73).

RESULTS

In study 1, SVR rate was 44.9%; that in male subjects (50.4%) was significantly (P < 0.0001) higher than in female subjects (36.4%). SVR rate significantly (P < 0.0001) decreased with 10-year age increments in both sexes. Multivariate logistic regression analysis revealed that age, F score, platelet count, and HCV load were SVR-related factors. In study 2, SVR rate in the 72-week group (67.1%) was significantly (P = 0.0020) higher than in the 48-week group (46.2%).

CONCLUSIONS

Patients with CHCV genotype 1 infection should be treated with PEG-IFN plus ribavirin combination therapy as early as possible, and 72 weeks' treatment is recommended in patients with LVR regardless of age.

EGFR gene alterations as a prognostic biomarker in advanced esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) exhibits abnormalities in epidermal growth factor receptor (EGFR) gene. To identify a prognostic marker, the overexpression of EGFR protein, mutations in EGFR and p53 mutations were analyzed in pretreatment biopsy specimens removed from T3-4 and/or M1 LYM ESCC patients who received chemoradiotherapy. A silent mutation comprised of a single nucleotide polymorphism (SNP) at codon 787 of exon 20 of the EGFR gene was found in 19 patients (33%). In multivariate analysis, a significant difference was seen in the overall survival (odds ratio; 2.347, 95% confidence interval; 1.183-4.656, p = 0.015) between patients with and without the EGFR heterozygous genotype. Among the 57 eligible patients, 3-year survival rates was 21%, while in patients with EGFR heterozygous genotype the rate were 0%. However, neither overexpression of EGFR nor p53 mutations was associated with the overall survival. These results suggest that the EGFR SNP at codon 787 of exon 20 determined in pretreatment biopsy specimens may be a clinically useful biomarker for predicting the prognosis of ESCC patients.

Concordant DNA methylation in synchronous colorectal carcinomas

Epigenetic changes have been proposed as mediators of the field defect in colorectal carcinogenesis, which has implications for risk assessment and cancer prevention. As a test of this hypothesis, we evaluated the methylation status of eight genes (MINT1, 2, 31, MLH1, p16, p14, MGMT, and ESR1), as well as BRAF and KRAS mutations, in 57 multiple colorectal neoplasias (M-CRN) and compared these to 69 solitary colorectal cancers (S-CRC). There were no significant differences in methylation between M-CRNs and S-CRCs except for p14 and MGMT that was significantly higher in M-CRNs than S-CRCs (16.1% versus 9.3%; 26.5% versus 17.3%, respectively; P < 0.05). We found significant (P < 0.05) correlations for MINT1 (r = 0.8), p16 (r = 0.8), MLH1 (r = 0.9), and MGMT (r = 0.6) methylation between tumors pairs of the same site (proximal/proximal and distal/distal). KRAS showed no concordance in mutations. BRAF mutation showed concordance in proximal site pairs but was discordant in different site pairs. Histologically, eight of 10 paired cancers with similar locations were concordant for a cribriform glandular configuration. We conclude that synchronous colorectal tumors of the same site are highly concordant for methylation of multiple genes, BRAF mutations, and a cribriform glandular configuration, all consistent with a patient-specific predisposition to particular subtypes of colorectal cancers. Screening for and secondary prevention of colon cancer should take this fact into account.

[Two cases of gastric cancer expressing Glypican 3, but producing AFP with different lectin affinity]

We encountered 2 cases of AFP-producing gastric cancer. In the first patient, an 82-year-old man was found to have advanced type II advanced carcinoma in the stomach with a massive tumor embolus in the portal vein. In the second case, an 80-year-old man was given a diagnosis of multiple liver metastases of gastric cancer with portal vein thrombosis. Our diagnosis of gastric cancer in both cases was AFP-producing. It was supposed that the elevation of serum level of AFP might be caused by enteroblastic differentiation in the first case and hepatoid differentiation in the second case. Although, in both cases, the biopsy specimens of the gastric neoplasm proved moderately to poorly differentiated adenocarcinoma without hepatoid differentiation, the localization of Glypican 3 in gastric cancer cells was observed using immunostaining with a monoclonal antibody. In both cases, Glypican 3 was a sensitive and useful marker for AFP-producing gastric cancer with or without hepatoid differentiation.

Prokinetics influence the pharmacokinetics of rabeprazole

BACKGROUND

Proton pump inhibitors (PPIs) are unstable at a low PH. Accelerated transfer of PPIs to the upper small intestine may influence the pharmacokinetics of PPIs.

AIM

To see if concomitant use of mosapride citrate with rabeprazole sodium influences the pharmacokinetics of the PPI.

METHODS

Two-way crossover pharmacokinetic studies were conducted in 9 healthy subjects. 20 mg of rabeprazole was given orally and plasma was obtained before and 1, 2, 3, 4, 5, 6 and 8 h after the dosing. Two weeks later, 5 mg of mosapride was given concomitantly with rabeprazole and plasma was collected as above. The plasma concentrations of rabeprazole were determined by high-performance liquid chromatography. The maximum plasma concentrations (C(max)) and the area under the time-plasma concentration curve (AUC) of rabeprazole, and the time to maximum plasma concentration (t(max)) were compared in the presence or absence of mosapride.

RESULTS

Concomitant use of mosapride resulted in significant increases of mean C(max) and mean AUC with ratios of 1.57 and 1.47, respectively. The median t(max) changed from 4 to 3 h, although the change was not significant.

CONCLUSIONS

Mosapride significantly influenced pharmacokinetics of rabeprazole. Co-administration of mosapride could have some favorable effect in PPIs-based therapy.

Magnitude of CD8 T-cell responses against hepatitis C virus and severity of hepatitis do not necessarily determine outcomes in acute hepatitis C virus infection

AIM

We investigated the relationship between the magnitude of comprehensive hepatitis C virus (HCV)-specific CD8(+) T-cell responses and the clinical course of acute HCV infection.

METHODS

Six consecutive patients with acute HCV infection were studied. Analysis of HCV-specific CD8(+) T-cell responses was performed using an interferon-gamma-based enzyme-linked immunospot assay using peripheral CD8(+) T-cells, monocytes and 297 20-mer synthetic peptides overlapping by 10 residues and spanning the entire HCV sequence of genotype 1b.

RESULTS

Five patients presented detectable HCV-specific CD8(+) T-cell responses against a single and different peptide, whereas 1 patient showed responses against three different peptides. Neither the magnitude of HCV-specific CD8(+) T-cell responses nor the severity of hepatitis predicts the outcome of acute hepatitis. The maximum number of HCV-specific CD8(+) T-cells correlated with maximum serum alanine aminotransferase level during the course (r = 0.841, P = 0.036).

CONCLUSIONS

HCV-specific CD8(+) T-cell responses were detectable in all 6 patients with acute HCV infection, and 6 novel HCV-specific CTL epitopes were identified. Acute HCV infection can resolve with detectable HCV-specific CD8(+) T-cell responses, but without development of antibody against HCV.

Upregulation of indoleamine 2,3-dioxygenase in hepatocyte during acute hepatitis caused by hepatitis B virus-specific cytotoxic T lymphocytes in vivo

BACKGROUND/AIMS

Indoleamine-2,3-dioxygenase (IDO) is a tryptophan-catabolizing enzyme inducing suppression of T-cell function and immune tolerance. In hepatitis B virus (HBV) transgenic (Tg) mice, the adoptive transfer of HBV-specific cytotoxic T lymphocytes (CTL) causes a necroinflammatory liver disease that is histologically similar to acute viral hepatitis in man. The present study aimed to determine IDO expression in the liver and hepatocytes during an acute hepatitis model.

METHODS

Serum l-kynurenine (l-Kyn) concentration in HBV Tg mice administered with HBV-specific CTL was measured over time, together with serum levels of alanine aminotransferase (ALT). Furthermore, we examined the expression of IDO in the total liver and isolated hepatocytes of HBV Tg mice after CTL injection using immunohistochemical analysis and reverse-transcription polymerase chain reaction (PCR).

RESULTS

In HBV Tg mice, HBV-specific CTL induced, over the course of several days, a chronic increase in serum l-Kyn levels, which was associated with a sustained enhancement of liver IDO activity. In particular, IDO expression was enhanced in the liver parenchymal cells (hepatocytes) after HBV-specific CTL injection both in immunohistochemical analysis and in reverse-transcription PCR. Moreover, murine recombinant interferon-gamma (IFN-gamma) directly increased the IDO expression in primary hepatocytes in vitro.

CONCLUSIONS

Cytotoxic T lymphocytes transduction results in the upregulation of IDO, which might downregulate T-cell responsiveness. Our findings provide evidence that hepatocyte itself expresses IDO and increases levels of l-Kyn in the blood in acute lethal hepatitis of mice. These data indicate that HBV infection facilitates the induction of IDO in response to proinflammatory cytokines, particularly IFN-gamma.

Clinicopathological comparison of the World Health Organization/Wotherspoon score to the Groupe d'Etude des Lymphomes de l'Adult grade for the post-treatment evaluation of gastric mucosa-associated lymphoid tissue lymphoma

BACKGROUND AND AIM

The World Health Organization (WHO) has adopted criteria for the histological differential diagnosis of gastric extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (GML) based on the criteria proposed by Wotherspoon in 1993 (WHO/Wotherspoon score). These histological criteria are commonly used by pathologists for initial diagnoses, but have not been adopted uniformly for the post-treatment evaluation of GML. In 2003, the Groupe d'Etude des Lymphomes de l'Adult (GELA) proposed a new histological grading system (GELA grade) in preference to use of the WHO/Wotherspoon score for post-treatment evaluation. In the present study, we compared the WHO/Wotherspoon and GELA systems to examine which histological criterion is better for post-treatment evaluation.

METHODS

Fourteen cases of GML under long-term follow up were initially diagnosed according to the WHO criteria with detailed immunohistology, and were periodically evaluated with both histological criteria after anti-Helicobacter pylori treatment. They were also evaluated based on histological stromal changes accompanying the disappearance of lymphoma tissue.

RESULTS

The study showed strong similarities between the WHO/Wotherspoon and GELA systems and no clear advantage of either system for post-treatment evaluation. The GELA grade could not be used for the evaluation of changes in the degree of lymphoma infiltration from pre- to post-treatment because the four-item scale is not comparable with the formal six-point WHO/Wotherspoon scale. Stromal changes in the lamina propria, including an empty appearance and fibrosis, were correlated with lymphoma reduction after treatment and appear to be good indicators for post-treatment evaluation.

CONCLUSION

We propose the utilization of the WHO/Wotherspoon score accompanied by the assessment of stromal changes for the post-treatment evaluation of GML.

The onset of angiogenesis in a multistep process of esophageal squamous cell carcinoma

Microvessel density (MVD) is an excellent predictive biomarker regarding tumor stage and survival in esophageal squamous cell carcinomas (ESCCs). However, it is obscure when tissues initiate angiogenesis in the malignant transformation of human esophageal squamous epithelium. To investigate the onset of angiogenesis in the multistep progressive process of ESCCs, immunohistochemical staining for CD31, CD105, and vascular endothelial growth factor receptor 2 (VEGFR-2) was performed in normal epithelium, Lugol-unstained lesions with non-dysplastic epithelium (LULs-NDE), low-grade dysplasia (LGD), and high-grade dysplasia (HGD) samples. There were significant differences in the mean MVD for CD31 and CD105 between LULs-NDE and LGD (p less than 0.001, p less than 0.001), and between LGD and HGD (p less than 0.001, p=0.006), respectively. Furthermore, a significant difference in MVD for CD105 was seen in normal controls and LULs-NDE (p=0.002), while thick vessels (less than 10m m) stained with anti-CD105 were not present in normal controls and LULs-NDE despite the presence of these thickened vessels in dysplasia. Our results suggest that CD105 is an efficient marker protein to determine MVD, suggesting that the angiogenic switch occurs at the earliest stage of dysplastic transformation in ESCC.

Causal relationships between esophageal squamous cell carcinoma and nephrotic syndrome

We present a case of membranous nephropathy (MN) associated with esophageal squamous cell carcinoma (ESCC) with a high serum level of squamous cell carcinoma antigen (SCC). ESCC reached complete response (CR) for radiotherapy, with a partial remission of the proteinuria and decreased serum SCC levels. Six months after radiotherapy, the ESCC recurred, and the patient was treated with endoscopic mucosal resection (EMR), achieving a pathologic CR and disappearance of proteinuria and normalized serum SCC levels. The correlation of proteinuria and the serum level of SCC indicates that SCC could be a pathogenic antigen, responsible for the pathogenesis of MN in this patient.

Valpha14 NKT cells activated by alpha-galactosylceramide augment lipopolysaccharide-induced nitric oxide production in mouse intra-hepatic lymphocytes

Valpha14 natural killer T (Valpha14 NKT) cells activated by alpha-galactosylceramide (alpha-GalCer) secrete a large amount of Th1 and Th2 cytokines. IFN-gamma plays a crucial role in the inflammation response, and is also known as an activator of nitric oxide (NO) production. We previously reported that lipopolysaccharide (LPS)-induced NO production is augmented by alpha-GalCer in mouse peritoneal cells. Since the liver is susceptible to LPS stimulation via the portal vein, we examined the effect of alpha-GalCer on LPS-induced NO production in murine intra-hepatic lymphocytes (IHLs). Although IHLs augmented LPS-induced NO production by alpha-GalCer administration, such an augmentation was not observed in non-treated mice. Furthermore, alpha-GalCer did not augment LPS-induced NO production in IHLs from IFN-gamma knockout mice. In flow cytometry analysis of IHLs from alpha-GalCer-treated mice, the ratio and number of F4/80- and TLR4-positive cells rose as compared with non-treated mice. The liver injury may be induced by LPS and NO under the condition where Valpha14 NKT cells were activated.

Immune responses in hepatitis C virus infection and mechanisms of hepatitis C virus persistence

Immune responses against hepatitis C virus (HCV) play a crucial role in the pathogenesis of chronic hepatitis C. HCV infection often persists and leads to chronic hepatitis and eventually cirrhosis. Accumulated data suggest that HCV proteins suppress host immune responses through the suppression of functions of immune cells, such as cytotoxic T lymphocytes, natural killer cells, and dendritic cells. They also suppress the type 1 interferon signaling system. The resulting insufficient immune responses against HCV lead to the sustained infection. The appropriate control of immune responses would contribute to the eradication of HCV and the improvement of hepatitis, but there are still many issues to be clarified. This review describes the scientific evidence to support these emerging concepts, and will touch on the implications for improving antiviral therapy.

Scoring system for predicting response to chemoradiotherapy, including 5-Fluorouracil and platinum, for patients with esophageal cancer

We have retrospectively evaluated clinical data before therapy to enable reliable prediction of the response of esophageal cancer to chemoradiotherapy (CRT). We analyzed 108 patients who received 5-fluorouracil and platinum combined with 60 Gy radiation for esophageal cancer. Factors significantly related to response were extracted by use of logistic regression analysis, and a response score (RS) was prepared by combining these factors. By multivariate analysis, nutritional status, T stage, M stage, and alkaline phosphatase were selected as significant factors that contributed independently to the response of esophageal cancer to CRT (P < 0.05). The odds ratios of the four selected factors was approximated and scored. The group with a high RS was found to include patients with complete response with a significantly higher frequency than the group with a low score (72.7% vs. 14.8%, P < 0.001). The RS is suggested to be an appropriate scoring system with which to predict response for these patients.

Dendritic cells stimulated with cytidine-phosphate-guanosine oligodeoxynucleotides and interferon-alpha-expressing tumor cells effectively reduce outgrowth of established tumors in vivo

Dendritic cells (DC) are potent antigen-presenting cells that elicit immune responses to foreign antigens. We have previously demonstrated the synergistic effects of cytidine-phosphate-guanosine (CpG) oligodeoxynucleotides (ODN) and interferon (IFN)-alpha on DC maturation in vitro. In the present study, the antitumor effects of DC preincubated with IFN-alpha gene-overexpressing murine colorectal cancer MC38 cells (MC38-IFN-alpha) and CpG ODN were evaluated in a poorly immunogenic murine cancer system. When we injected DC preincubated with MC38-IFNalpha and CpG ODN subcutaneously to mice bearing MC38 wild-type tumors, the outgrowth of the established parental tumors was suppressed significantly compared with that following administration of DC with MC38-IFN-alpha (P = 0.008). All mice injected with DC preincubated with MC38-IFN-alpha and CpG ODN rejected a subsequent parental tumor challenge. Immunohistochemical and flow cytometric analyses showed that CD4(+), CD8(+), and NK1.1(+) cells markedly infiltrated the established tumors of mice treated with DC preincubated with MC38-IFN-alpha and CpG ODN. From the results in immune cell-depleted mice, CD4(+) and asialo-GM-1(+) cells seemed to contribute to the antitumor effects induced by the combination DC therapy. Furthermore, non-specific cytolysis was detected when splenocytes of mice inoculated with DC preincubated with MC38-IFNalpha and CpG ODN were used as effector cells. Using an interleukin (IL)-12-neutralizing antibody it was suggested that IL-12 stimulates natural killer cells and contributes in part to the antitumor effects induced by DC incubated with CpG ODN and IFN-alpha. As DC-based immunotherapy with CpG ODN and IFN-alpha-expressing tumor cells induces a potent antitumor immune response, it should be considered for clinical application.

Role of Valpha14+ NKT cells in the development of Hepatitis B virus-specific CTL: activation of Valpha14+ NKT cells promotes the breakage of CTL tolerance

CTLs are thought to be major effectors for clearing viruses in acute infections including hepatitis B virus (HBV). Persistent HBV infection is characterized by a lack of or a weak CTL response to HBV, which is thought to reflect tolerance to HBV antigens. In the present study, we found that alpha-galactosylceramide (alpha-GalCer), a ligand for Valpha14-positive NKT cells, strongly enhanced the induction and proliferation of HBV-specific CTLs by HBsAg. In HBsAg transgenic mice, which are thought to be tolerant to HBV-encoded antigens, administration of HBsAg or alpha-GalCer alone failed to induce HBsAg-specific CTLs, but they were induced by co-administration of both compounds. Furthermore, by limiting dilution analysis, we confirmed the existence of HBsAg-specific CTL precursors in the HBsAg transgenic mice immunized with HBsAg and alpha-GalCer. A blocking experiment using antibodies to cytokines and CD40 ligand showed that IL-2 and CD40-CD40L interaction mediate the enhancement of CTL induction caused by alpha-GalCer through NKT cell activation. Our results may open up a new method for clearing the virus from patients with persistent HBV infection.

Intrahepatic status of regulatory T cells in autoimmune liver diseases and chronic viral hepatitis

AIM

Regulatory T cells (Tregs) maintain immunological tolerance and suppress autoreactive immune responses. We evaluated the intrahepatic status of Tregs in patients with autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC), chronic hepatitis C (CH-C), or chronic hepatitis B (CH-B).

METHODS

We analyzed 85 patients (20 AIH, 22 PBC, 27 CH-C, and 16 CH-B) and 14 controls. Using liver tissue samples obtained by needle biopsy or from marginal parts of resected metastatic liver tumors in the controls, immunohistochemical analyses of forkhead box P3(+), which is a specific marker for Tregs, CD4(+), and CD8(+) cells were performed.

RESULTS

Intrahepatic Tregs were significantly more infiltrated in patients with liver diseases than in the controls. There were significantly fewer intrahepatic Tregs in the AIH patients than in the PBC patients (P = 0.037). Patients with alow frequency of intrahepatic Tregs were detected significantly more in the AIH and CH-B groups than in the PBC and CH-C groups (P < 0.05). In addition, the frequency of Tregs decreased in the liver of PBC patients as the pathological stage of the disease advanced. We found significantly less infiltration of CD4(+) T cells in AIH than in other diseases (P < 0.05). Liver-infiltrating CD8(+) T cells were detected more frequently in the CH-B group than in other groups (P < 0.003).

CONCLUSION

Intrahepatic Tregs were increased in both patients with autoimmune liver diseases and those with viral hepatitis. In autoimmune liver diseases, intrahepatic Tregs were fewer in the AIH patients than in the PBC patients.

Restoration of innate host defense responses by oral supplementation of branched-chain amino acids in decompensated cirrhotic patients

AIM

It has been reported that host defense responses, such as phagocytic function of neutrophils and natural killer (NK) cell activity of lymphocytes, are impaired in cirrhotic patients. The aim of the present study was to examine the effects of oral supplementation of branched-chain amino acids (BCAA) on host defense mechanisms in peripheral blood of patients with decompensated cirrhosis.

METHODS

Ten patients with decompensated cirrhosis received 12 g BCAA daily for 3 months. Phagocytic function of neutrophils and NK activity of lymphocytes as well as serum albumin levels and Fisher's ratios were determined before and at 1 and 3 months of BCAA supplementation. For quantification of phagocytic function, fluorescent intensities of cells in the neutrophil region in the cytogram were determined by flow cytometry after incubation of whole blood with fluorescent microspheres. NK activity was estimated by (51)Cr release assay using K-562 cell line as target cells.

RESULTS

Phagocytic function of neutrophils was significantly improved by 3-month BCAA supplementation (P < 0.01). Thechanges of NK activity were also significant at 3 months of supplementation compared with before supplementation (P < 0.01). Fisher's ratios were significantly increased at 3 months of BCAA supplementation compared with those before oral supplementation (P < 0.05), although the changes of serum albumin level were not statistically significant.

CONCLUSIONS

BCAA oral supplementation improved phagocytic function of neutrophils and NK activity of lymphocytes in cirrhotic patients. BCAA supplementation may reduce the risk of bacterial and viral infection in patients with decompensated cirrhosis.

[Cost effectiveness of chemoradiotherapy with cisplatin/fluorouracil and nedaplatin/fluorouracil for patients with esophageal cancer]

OBJECTIVE

To assess the cost-effectiveness of chemoradiotherapy (CRT) regimens for patients with esophageal cancer, we compared two regimens consisting of 5-fluorouracil (5-FU) and cisplatin (CDDP) or 5-FU and nedaplatin (CDGP) with radiotherapy.

METHODS

Medical records of 108 patients with esophageal cancer who received CRT of 5-FU+CDDP (CDDP group) or 5-FU+CDGP (CDGP group) were analyzed. In both groups, most of the patients were men with a pathological diagnosis of squamous cell carcinoma. A Markov model was used to show the clinical courses of esophageal cancer after the CRT therapy. An outcome used for economic evaluation was life year gained (LYG). We calculated the cost per-effectiveness ratio (CER) and incremental cost effectiveness ratio (ICER). Clinical effectiveness and costs in this model were investigated retrospectively, and the costs were estimated from the perspective of the medical institution. Sensitivity analysis was used to check the robustness of this model.

RESULTS

In CDDP and CDGP group, LYG was 18.23 and 16.31 years and CER was 270,373 and 406,264 yen/LYG, respectively. As a result, ICER was .883,999 yen/LYG. The sensitivity analysis showed that this model was definitely robust.

CONCLUSION

Our results suggested that CDDP could prolong LYG with less cost than CDGP and that CRT of 5-FU and CDDP was markedly cost effective treatment.