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Biomedical subjects

Hiroyuki Kuwano

Publications and source records attributed to Hiroyuki Kuwano.

At least 73 records · Page 4Linked to original sources
PubMed2005

Prevention of hepatitis B virus infection from hepatitis B core antibody-positive donor graft using hepatitis B immune globulin and lamivudine in living donor liver transplantation.

BACKGROUND: Hepatic grafts from hepatitis B surface antigen-negative and anti-core antibody (HBcAb)-positive donors have been shown to transmit hepatitis B virus (HBV) infection. Recently, it has been reported that combined hepatitis B immune globulin (HBIG) and lamivudine therapy is effective in the prevention of hepatitis B recurrence after living donor liver transplantation (LDLT). In this report, we assessed the efficacy of combined HBIG and lamivudine therapy in preventing HBV transmission by graft with HBcAb-positive donors. METHODS: We studied 22 patients who had undergone LDLT with allografts from HBcAb-positive living donors at Gunma University Hospital and Kyushu University Hospital. Long-term combined HBIG and lamivudine therapy were administrated to all recipients. Serum samples from the donor and recipient were tested for HBcAb, HBV DNA, and hepatitis B surface antibody. Liver biopsies from grafts were tested for HBV DNA. RESULTS: All recipients were HBcAb negative before LDLT. All of the donor livers were HBV DNA positive at the time of LDLT. All of the recipients had HBsAb titers greater than 300 mIU/ml 4 weeks after LDLT, and remained 100 mIU/ml thereafter. None of the recipients have become infected with HBV with a follow-up of 25-86 months. CONCLUSIONS: Perioperative combined HBIG and lamivudine therapy can prevent HBV infection in recipients who receive liver grafts from HBcAb-positive donors.

Adolescent↗
PubMed2005

Studies on the variation in clinical laboratory data and safety evaluation of pharmaceuticals.

The safety of pharmaceuticals has become increasingly important not only in daily medical treatment but also in clinical trials. Although clinical laboratory data are more objective than clinical symptoms, the determination as to whether they indicate abnormal variations depends largely upon the clinical judgment of physicians. The process of determination has not been sufficiently objectified. The present study investigated the indices of criteria for variations in clinical laboratory data obtained in clinical trials. Then, detection rates of abnormal variations were compared between our determination method that employs the reference change value (RCV) expressing the width of biological variation for each test component and conventional determination methods. The study also demonstrated that by combining standard values and the RCV for determination, abnormal variations were found at a rate greater than 50%. The method we propose was applied to the safety evaluation of pharmaceuticals. In clinical trials on the antiviral drug ribavirin administered alone, components of laboratory tests were selected that should be noted in studies on its effects. Expect for decreases in red blood cell counts and hemoglobin values, which are closely associated with anemic symptoms and well known to hepatologists, the increasing trend in platelet counts and decreasing trend in albumin were found to be laboratory test components that should be paid attention to, even though they may not be obvious.

Antiviral Agents↗
PubMed2005

Comparison of the function of the beta(C) and beta(E) subunits of activin in AML12 hepatocytes.

To investigate the function of the beta(C) and beta(E) subunits of activin, we overexpressed these subunits in AML12 cells, a normal hepatocyte cell line, using adenovirus vector. Overexpression of the beta(C) subunit increased [3H]thymidine incorporation and the cell number. In contrast, both [3H]thymidine incorporation and the cell number were reduced in the beta(E) overexpressing cells. When AML cells overexpressing the beta(E) subunit were cultured in medium containing 1% serum for 48 h, many of the cells died by apoptosis, whereas cells overexpressing the beta(C) subunit or beta-galactosidase survived in the same condition. To examine dimer formation, the beta(C) and beta(E) subunits were expressed in AML12 cells. In these cells, the beta(C) homodimer, the beta(E) homodimer and the beta(C)-beta(E) heterodimer were detected. When the expression level of the beta(E) subunit was increased, formation of the beta(E) homodimer was increased, while formation of the beta(C)-beta(E) heterodimer was slightly reduced. Overexpression of the beta(E) subunit did not significantly affect the formation of the beta(C) homodimer. These results indicate that the beta(C) and beta(E) subunits form homo- and heterodimers, and that the functions of the two subunits are quite different.

Animals↗
PubMed2005

[Clinical outline of Barrett's esophagus].

Barrett's esophagus is one of the important gastrointestinal disease in Europe and the United States. It was recognized as not only complication of reflux esophagitis, but also pre-malignant lesion of adenocarcinoma. Recently, realization of Barrett's esophagus is attentioned in Japan, because increasing of reflux esophagitis for westernization of eating habit, living habit and aging of the population. In this section, we present general consideration and clinical research of Barrett's esophagus. We expect Barrett's esophagus will gradually increase near the future and need to research abundantly about controversial point of Barrett's esophagus. We also think it is important to accumulate intensively the clinical data of Barrett's esophagus patients.

Adenocarcinoma↗
PubMed2005

[Effects of neutrophil elastase inhibitor on postoperative cytokine levels in patients after esophagectomy].

BACKGROUND: The purpose of this study is to examine the effects of neutrophil elastase inhibitor on postoperative cytokine levels in patients after esophagectomy. METHODS: Fifteen patients were divided into two groups; group 1: 9 patients receiving neutrophil elastase inhibitor (0.2 mg x kg(-1) x hr(-1) from the admission to ICU to extubation), group 2: 6 patients as a control. We measured neutrophil elastase activity, interleukin 1-beta, interleukin 6 and interleukin 8 preoperatively, just after the admission to ICU, and 24, 48 and 72 hours after the surgery. RESULTS: There were significant differences in neutrophil elastase activity and interleukin 8 in group 1 24 hours after the surgery, compared with those in group 2. The time necessary for mechanical ventilation in group 1 was shorter than that in group 2 (group 1: 44.7 +/- 24.7 hrs, group 2: 112.8 +/- 90.3 hrs, P = 0.048). CONCLUSIONS: The administration of neutrophil elastase inhibitor may be useful for patients after esophagectomy to reduce overexpression of plasma cytokine levels after surgery.

Cytokines↗
PubMed2004

alpha1-acid glycoprotein fucosylation as a marker of carcinoma progression and prognosis.

BACKGROUND: Serum alpha1-acid glycoprotein (AGP), an acute-phase protein secreted by the liver, carries alpha(1,3)-fucosylated structures on its 5 highly branched, N-linked sugar chains. METHODS: Serum AGP levels in patients with various types of malignancies (n=214 patients) were measured using an enzyme-linked immunosorbent assay with anti-AGP antibody. To investigate glycoforms that differed in their degree of branching and extent of fucosylation, serum AGP samples were analyzed by crossed affinoimmunoelectrophoresis (CAIE) with concanavalin A, and Aleuria aurantia lectin (AAL), and anti-AGP antibody. RESULTS: A significant difference (P <0.001) in serum AGP levels was observed in preoperative patients compared with levels in the healthy control group, but the levels in individual patients did not reflect their clinical status. Conversely, it was found not only that the patterns of AGP glycoforms differed widely in the patient group compared with the healthy control group, but they also changed depending on each patient's clinical status. Furthermore, AGP glycoforms seemed to be appropriate markers of disease progression and prognosis according to follow-up studies of 45 patients during prolonged preoperative and postoperative periods. CONCLUSIONS: Patients with advanced malignancies who had AGP glycoforms that contained highly fucosylated triantennary and tetraantennary sugar chains for long periods after surgery were likely to have a poor prognosis. However, patients who had AGP glycoforms without such changes were expected to have a good prognosis.

Biomarkers, Tumor↗
PubMed2004

Mutations of the epidermal growth factor receptor gene in lung cancer: biological and clinical implications.

Recently it has been reported that mutations in the tyrosine kinase domain of the epidermal growth factor receptor(EGFR) gene occur in a subset of patients with lung cancer showing a dramatic response to EGFR tyrosine kinase inhibitors. To gain further insights in the role of EGFR in lung carcinogenesis, we sequenced exons 18-21 of the tyrosine kinase domain using total RNA extracted from unselected 277 patients with lung cancer who underwent surgical resection and correlated the results with clinical and pathologic features. EGFR mutations were present in 111 patients (40%). Fifty-two were in-frame deletions around codons 746-750 in exon 19, 54 were point mutations including 49 at codon 858 in exon 21 and 4 at codon 719 in exon 18, and 5 were duplications/insertions mainly in exon 20. They were significantly more frequent in female (P < 0.001), adenocarcinomas (P = 0.0013), and in never-smokers (P < 0.001). Multivariate analysis suggested EGFR mutations were independently associated with adenocarcinoma histology (P = 0.0012) and smoking status (P < 0.001), but not with female gender (P = 0.9917). In adenocarcinomas, EGFR mutations were more frequent in well to moderately differentiated tumors (P < 0.001) but were independent of patient age, disease stages, or patient survival. KRAS and TP53 mutations were present in 13 and 41%, respectively. EGFR mutations never occurred in tumors with KRAS mutations, whereas EGFR mutations were independent of TP53 mutations. EGFR mutations define a distinct subset of pulmonary adenocarcinoma without KRAS mutations, which is not caused by tobacco carcinogens.

Adenocarcinoma↗
PubMed2004

Autocrine motility factor signaling enhances pancreatic cancer metastasis.

PURPOSE: Autocrine motility factor (AMF)/phosphoglucose isomerase (PGI) is a ubiquitous cytosolic enzyme that plays a key role in glycolysis. AMF/PGI is also a multifunctional protein that acts in the extracellular milieu as a potent mitogen/cytokine. Increased expression of AMF/PGI and its receptor has been found in a wide spectrum of malignancies and is associated with cancer progression and metastasis. Recent studies indicated that AMF is induced by hypoxia and enhances the random motility of pancreatic cancer cells. In the present study, the role and regulation of AMF in the growth and metastasis of pancreatic cancer cells were determined. EXPERIMENTAL DESIGN: In this study, we assessed whether overexpression of AMF in human pancreatic cancer cells enhances the liver metastasis using an orthotopic mouse tumor model. We also investigated the intracellular signal transduction pathways of AMF in human pancreatic cancer cell lines. RESULTS: Overexpression of AMF stimulated in vitro invasion of MIA PaCa-2 cells. In vivo, after orthotopic implantation into the pancreas of nude mice, parental and empty vector-transfected MIA PaCa-2 cells produced locally relatively small tumors with no evidence of liver metastasis, whereas AMF-transfected MIA PaCa-2 cells produced the large tumors and liver metastases. In addition, over-expression of AMF leads to down-regulation of E-cadherin expression associated with the up-regulation of the zinc-finger transcription factor SNAIL expression. CONCLUSIONS: The data submitted here show that AMF expression significantly contributes to the aggressive phenotype of human pancreatic cancer and thus may provide a novel prognostic and therapeutic target.

Aged↗
PubMed2004

Pretreatment evaluation of combined HIF-1alpha, p53 and p21 expression is a useful and sensitive indicator of response to radiation and chemotherapy in esophageal cancer.

Tumor hypoxia has been known to be associated with resistance to radiation and chemotherapy (CRT). Hypoxia-inducible factor-1alpha (HIF-1alpha), a transcription factor induced by hypoxic condition, plays a major role in the pleiotropic response observed under hypoxic conditions. It encodes proteins that play key roles in critical development and physiologic processes, including angiogenesis, glucose transport and erythropoiesis. On the other hand, cell cycle- and apoptosis-control genes p53 and p21 may play major roles in the tumor response to cytotoxic agents such as radiation and chemotherapy. Previous reports have suggested that the regulation of p53 and p21 is HIF-1-dependent. Our aim was to evaluate the expression of the HIF-1alpha, p53 and p21 proteins by immunohistochemistry in biopsy specimens of esophageal squamous cell carcinoma, which were obtained endoscopically from 65 patients before CRT, and then determine whether the levels of expression of these proteins predicted the clinical effectiveness of CRT in individual cancers. Also, to assess the relationship between expression of these proteins and cell death and cellular proliferation activity, we evaluated Ki67 expression and the apoptosis index (TUNEL). HIF-1alpha expression in esophageal cancer was significantly and negatively related to the response to CRT, independently of p53 and p21 expression. Interestingly, 44.4% (12/27) of the HIF-1alpha-negative group showed a complete response to therapy. There was no significant correlation between the expression of HIF-1alpha, p53 and p21 and proliferation and apoptosis. HIF-1alpha overexpression may predict resistance to CRT and may be a helpful guide in choosing between therapeutic strategies, such as intensive combined modality therapy vs. palliative therapy. Combined immunohistochemical evaluation of HIF-1alpha, p53 and p21 protein expression at the pretreatment biopsy is a very useful and powerful indicator of sensitivity to CRT in human esophageal cancer. Our data also indicate the importance of having a clear grasp of the degree of hypoxia (HIF-1alpha) of a tumor, rather than its cellular character (proliferation and apoptosis), to indicate the likely impact of CRT.

Biomarkers, Tumor↗
PubMed2004

Interferon-gamma differentially regulates susceptibility of lung cancer cells to telomerase-specific cytotoxic T lymphocytes.

There is accumulating evidence that peptides derived from the catalytic subunit of human telomerase reverse transcriptase (hTERT) are specifically recognized by CD8+ cytotoxic T lymphocytes. We investigated the cytotoxicity of a human leukocyte antigen (HLA)-A*2402-restricted hTERT-derived peptide 461-469 (hTERT461)-specific CD8+ T-cell clone, designated as K3-1, established from a healthy donor by repetitive peptide stimulation. This clone exhibited cytotoxicity against 4 out of 6 HLA-A24-positive lung cancer cell lines with positive telomerase activity but not 4 HLA-A24-negative examples. When the target cells were pretreated with 100 U/ml of interferon (IFN)-gamma for 48 hr, the susceptibility to K3-1 increased with PC9 cells but unexpectedly decreased with LU99 cells. However, in both cell lines, the expression of molecules associated with epitope presentation such as HLA-A24, transporters associated with antigen processing, low molecular weight polypeptide 7 and proteasome activator 28 was similarly increased after IFN-gamma treatment. Results of CTL assays using acid-extracted peptides indicated that the epitope increased on PC9 cells but not on LU99 cells after IFN-gamma treatment. Semi-quantitative reverse transcriptase polymerase chain reaction disclosed that the expression of hTERT was attenuated in LU99 but not in PC9 cells, accounting for the decreased cytotoxicity mediated by K3-1. The attenuation of the hTERT expression and K3-1-mediated cell lysis after IFN-gamma treatment was also observed in primary adenocarcinoma cells obtained from pulmonary fluid of a lung cancer patient. Our data underline the utility of peptide hTERT461 in immunotherapy for lung cancer, as with other malignancies reported earlier, and suggest that modulation of hTERT expression by IFN-gamma needs to be taken into account in therapeutic approach.

Blotting, Western↗
PubMed2004

Inactivation of 14-3-3sigma by hypermethylation is a rare event in colorectal cancers and its expression may correlate with cell cycle maintenance at the invasion front.

In many kinds of cancers, 14-3-3sigma, one of the cell cycle negative regulator, is inactivated by hypermethylation of the gene. In colorectal cancers, this study revealed that the hypermethylation of the 14-3-3sigma gene was an uncommon event and 14-3-3sigma expression was kept even in established colorectal cancer cell lines. Immunohistochemical study using surgical materials showed the expression of 14-3-3sigma was localized at the deep peripheral area of the tumor, so-called invasion front. According to the results of Ki-67 and cyclin B1 immunohistochemistry, 14-3-3sigma-positive cases maintained higher proliferative activity compared to 14-3-3sigma-negative cases at IF. However, a significant correlation between 14-3-3sigma expression and proliferative activity in CRC cells remains to be unsolved.

14-3-3 Proteins↗
PubMed2004

Plasma level of transforming growth factor beta1 measured from the azygos vein predicts prognosis in patients with esophageal cancer.

PURPOSE: Transforming growth factor (TGF)-beta regulates cell growth inhibition. When tumor cells lose their sensitivity to TGF-beta growth inhibition, the excess TGF-beta that results may act on tumor cells to facilitate tumor development. Previously, we have shown that an elevated systemic TGF-beta 1 level is not related to tumor progression in esophageal cancer (Y. Fukai et al., Int J Cancer 2003;104:161-6). We considered that systemic inflammation or chronic disease, in addition to the tumor, may influence the plasma TGF-beta level. Therefore, we examined the hypothesis that the plasma TGF-beta level measured from the azygos vein would independently predict tumor progression and prognosis in patients with esophageal cancer. EXPERIMENTAL DESIGN: Fifty-seven plasma samples were obtained intraoperatively from the azygos vein in patients with esophageal cancer. ELISA was used to quantify the plasma TGF-beta 1 levels, which were correlated with pathological features and patient survival. RESULTS: The mean plasma TGF-beta 1 level measured from the azygos vein of esophageal cancer patients was 5.09 +/- 0.48 ng/ml (mean +/- SE). The survival rates of patients with a high TGF-beta 1 level (defined as a level above the 4.6 ng/ml level of normal controls) in the azygos vein were significantly lower than those of patients with a low TGF-beta 1 level (P = 0.0317). Moreover, the TGF-beta 1 level in the azygos vein was an independent prognostic factor for overall survival (P = 0.0474). CONCLUSIONS: The level of plasma TGF-beta 1 measured from the azygos vein is an independent predictor in patients with esophageal cancer and may reflect tumor progression more specifically because the azygos vein is responsible for venous return from the esophagus.

Adult↗
PubMed2004

Assessment of the function of the betaC-subunit of activin in cultured hepatocytes.

We assessed the function of the beta(C)-subunit of activin in hepatocytes. We studied the effect of conditioned medium of Chinese hamster ovary (CHO) cell line stably expressing the beta(C) gene (CHO-beta(C)) on growth of AML12 hepatocytes. We also examined the effect of recombinant activin C and transfection of the beta(C) gene by using adenovirus vector. CHO-beta(C) secreted activin C, a homodimer of the beta(C), as well as precursors of the beta(C). The conditioned medium of CHO-beta(C) increased both [(3)H]thymidine incorporation and the cell number in AML12 cells. It also supported survival of AML12 cells in a serum-free condition. Recombinant human activin C also increased both [(3)H]thymidine incorporation and the number of AML12 cells. Transfection of AML12 cells with the beta(C)-subunit led to the stimulation of [(3)H]thymidine incorporation. Analysis of the conditioned medium revealed that the beta(C)-subunit formed a heterodimer with the endogenous beta(A), the formation of which was dependent on the amount of beta(C) expressed. Recombinant activin C did not affect the binding of (125)I-activin A to its receptor or follistatin. These results indicate that activin C stimulates growth of AML12 cells. The beta(C)-subunit modifies the function of the beta(A)-subunit by multiple mechanisms.

Animals↗
PubMed2004

Serum interleukin-12 and interleukin-18 levels as a tumor marker in patients with esophageal carcinoma.

Interleukin (IL)-12 and IL-18 participate in tumor immunology. Serum IL-12 and IL-18 levels were determined in patients with esophageal carcinoma, and the relationship between clinicopathologic factors and prognosis was investigated. Peripheral blood samples were obtained from 15 healthy volunteers and from 70 patients with esophageal carcinoma before curative surgery. IL-12 and IL-18 levels were determined in each serum sample by enzyme-linked immunosorbent assay. Mean serum IL-12 and IL-18 levels were significantly higher in patients with esophageal carcinoma compared with healthy volunteers (P < 0.05) and mean serum IL-12 and IL-18 levels increased in patients as the pathologic stage progressed. A positive correlation was observed between serum IL-12 and IL-18 levels (P < 0.01). In patients with esophageal carcinoma, increasing serum IL-12 and IL-18 levels correlated with tumor growth and progression. The function of these two interleukin in the host immune response remains unclear. However, this part of the host immune response did not appear to contribute to the postoperative prognosis. Serum IL-12 and IL-18 levels might correlate with a certain depth of invasion and might be useful tumor markers in patients with esophageal carcinoma.

Adult↗
PubMed2004

The dependence of transforming growth factor-beta-induced collagen production on autocrine factor activin A in hepatic stellate cells.

The present study was conducted to examine the role of activin A in the activation of cultured rat hepatic stellate cells (HSC). HSC expressed mRNA for the beta(A)-subunit of activin and the type I and II activin receptors. TGF-beta increased the mRNA expression of the beta(A)-subunit of activin as well as the release of the beta(A) dimer, activin A. Exogenous activin A activated HSC and increased the expression of alpha-smooth muscle actin and collagen. Exogenous follistatin, an antagonist of activin A, blocked not only the effect of activin A but also the effect of TGF-beta on the expression of type I collagen. Similarly, follistatin inhibited TGF-beta-induced secretion of collagen from HSC. Additionally, the effect of TGF-beta was markedly reduced in HSC overexpressing the dominant-negative type II activin receptor. In contrast, the effect of activin A on the collagen production was not affected in HSC overexpressing the dominant-negative type II TGF-beta receptor. In conclusion, an autocrine factor activin A mediates part of the action of TGF-beta on the production of collagen in HSC. The results also suggest that follistatin may be useful for the treatment of hepatic fibrosis.

Activin Receptors, Type I↗
PubMed2004

Increased expression of c-Ski as a co-repressor in transforming growth factor-beta signaling correlates with progression of esophageal squamous cell carcinoma.

Transforming growth factor-beta (TGF-beta) regulates cell growth inhibition, and inactivation of the TGF-beta signaling pathway contributes to tumor development. In our previous study, altered expression of TGF-beta, TGF-beta-specific receptors and Smad4 was shown to correlate with tumor progression in esophageal squamous cell carcinoma (SCC). These components, however, were maintained normally in some patients with esophageal SCC. In our study, the mechanism by which aggressive esophageal SCC maintains these components was investigated, with particular emphasis on the participation of c-Ski and SnoN as transcriptional co-repressors in TGF-beta signaling. Immunohistochemistry for c-Ski and SnoN was carried out on surgical specimens obtained from 80 patients with esophageal SCC. The expression of c-Ski and SnoN was also studied in 6 established cell lines derived from esophageal SCC and compared to an immortalized human esophageal cell line by Western blotting. High levels of expression of c-Ski, detected immunohistologically, were found to correlate with depth of invasion (p = 0.0080) and pathologic stage (p = 0.0447). There was, however, no significant correlation between expression of SnoN and clinicopathologic characteristics. A significant correlation between c-Ski and TGF-beta expression was observed. Moreover, in patients with TGF-beta negative expression, the survival rates of patients with c-Ski positive expression were significantly lower than those of patients with c-Ski negative expression (p = 0.0486). c-Ski was expressed at a high level in 5 of 6 cell lines derived from esophageal SCC compared to immortalized esophageal keratinocytes. Furthermore, the cyclin-dependent kinase (CDK) inhibitor, p21 that was up-regulated by TGF-beta signaling was expressed at a low level in the 5 cell lines. The expression of c-Ski protein as a transcriptional co-repressor in TGF-beta signaling seems to be correlated with tumor progression of esophageal SCC.

Adult↗
PubMed2004

Prognostic model of pulmonary adenocarcinoma by expression profiling of eight genes as determined by quantitative real-time reverse transcriptase polymerase chain reaction.

PURPOSE: Recently, several expression-profiling experiments have shown that adenocarcinoma can be classified into subgroups that also reflect patient survival. In this study, we examined the expression patterns of 44 genes selected by these studies to test whether their expression patterns were relevant to prognosis in our cohort as well, and to create a prognostic model applicable to clinical practice. PATIENTS AND METHODS: Expression levels were determined in 85 adenocarcinoma patients by quantitative reverse transcriptase polymerase chain reaction. Cluster analysis was performed, and a prognostic model was created by the proportional hazards model using a stepwise method. RESULTS: Hierarchical clustering divided the cases into three major groups, and group B, comprising 21 cases, had significantly poor survival (P =.0297). Next, we tried to identify a smaller number of genes of particular predictive value, and eight genes (PTK7, CIT, SCNN1A, PGES, ERO1L, ZWINT, and two ESTs) were selected. We then calculated a risk index that was defined as a linear combination of gene expression values weighted by their estimated regression coefficients. The risk index was a significant independent prognostic factor (P =.0021) by multivariate analysis. Furthermore, the robustness of this model was confirmed using an independent set of 21 patients (P =.0085). CONCLUSION: By analyzing a reasonably small number of genes, patients with adenocarcinoma could be stratified according to their prognosis. The prognostic model could be applicable to future decisions concerning treatment.

Adenocarcinoma↗