Kiyohiro Higuchi

Effect of interleukin-8 on production of tumor-associated substances and autocrine growth of human liver and pancreatic cancer cells.

Abstract We have previously reported that human liver cancer cell lines produce interleukin-8 (IL-8) at high levels. Those tumor cells appeared to express two kinds of IL-8 receptor on their surface. In order to analyze the role of IL-8 on the biological characteristics of those tumor cells, we suppressed IL-8 production from human liver (HuH-7 and HuCC-T1) and pancreatic cancer cell lines (HuP-T4) by treatment with IL-8 antisense oligonucleotides. Suppression of IL-8 production resulted not only in inhibition of cell growth, but also in an increase in the concentrations of some tumor-associated substances such as carbohydrate antigen 19-9 (CA19-9) in the medium. These data indicate that IL-8 produced by human liver and pancreatic tumors may act as an autocrine growth factor and may control the production of some tumor-associated substances. Furthermore, surface expression of sialyl-Lewisa, which is a ligand for ELAM-1 on human umbilical vein endothelial cells (HUVEC), HuCC-T1 and HuP-T4 cells was decreased and the attachment of these tumor cells to HUVEC was inhibited by treatment with IL-8 antisense oligonucleotide. Since the soluble form of CA19-9 (sialyl-Lewisa) was shown to inhibit the tumor cell binding to HUVEC, the decrease in release of CA19-9 into the medium and increase in the expression of sialyl-Lewisa on the cell surface may suggest that IL-8 production from the tumor cells enhances metastatic potential by augmenting the binding activity of the tumor cells to HUVEC. These data demonstrate that a cytokine produced by tumor cells may function as an autocrine growth factor and affect tumor cell dissemination.

Interleukin‐6 functions as an autocrine growth factor in a cholangiocarcinoma cell line

Abstract The tumour cells of a human cholangiocarcinoma cell line, HuCC‐T1, were found to express mRNA of interleukin‐6 (IL‐6) and to secrete a large amount of biologically active IL‐6 in the culture medium at the concentration of 22.6 ng/mL. Interleukin‐6 was demonstrated in the cytoplasm of the cells by immunohistochemical staining. Furthermore, these cells showed the presence of receptors for IL‐6 on the surface, and DNA synthesis of the cells was stimulated by the exogenous addition of recombinant human IL‐6 into the culture medium. The cell growth was significantly inhibited in the presence of anti‐human IL‐6 antibody in the culture medium. These findings indicate that IL‐6 is one of the autocrine growth factors of this cell line in vitro.

Phenotypic analysis of circulating and intrahepatic dendritic cell subsets in patients with chronic liver diseases.

BACKGROUND/AIMS Dendritic cells (DCs) are the most potent professional antigen-presenting cells. Although two subsets of circulating DCs, lineage(-)CD11c(+)CD4(low) (CD11c(+)DCs) and lineage (-)CD11c(-)CD4(+)CD123(+) (CD123(+)DCs) are identified in humans, the role of each DC subset in the immunopathogenesis of liver diseases is unknown. METHODS We examined the numbers and activation status of each DC subset in the circulation and in the inflamed livers in patients with chronic liver diseases by flow cytometry and immunohistochemistry. RESULTS The numbers of circulating CD11c(+)DCs were inversely correlated with serum alanine aminotransferase (ALT) levels in patients with chronic viral hepatitis, and that the expression of costimulatory molecules on circulating CD11c(+)DCs in patients with chronic viral hepatitis was significantly up-regulated in patients with high serum levels of ALT. Both DCs are also identified in the livers by flow cytometry, and the expression of costimulatory molecule CD40 on those DCs was significantly higher in liver DCs than that in circulating DCs. Moreover, the ratios of CD11c(+)DCs/CD123(+)DCs were higher in liver DCs (mean+/-SD, 7.2+/-6.0) than those of circulating DCs (4.0+/-4.6). Immunohistochemically, CD11c(+) or CD123(+) cells and CD83(+) activated DCs were observed mostly in portal areas with mononuclear cell infiltration in various liver diseases. These overall data suggest that DCs, especially CD11c(+)DCs, could be associated with the necroinflammatory response in the liver of chronic viral liver diseases. CONCLUSIONS DCs, especially CD11c(+)DCs, may be involved in the immunopathogenesis of chronic liver diseases.

Primary biliary cirrhosis in japan: National survey by the subcommittee on autoimmune hepatitis

SummaryA total of 280 cases of primary bijiary cirrhosis were reported from 86 institutes in Japan, of whom 208 were middle aged women. Four clinical stages (asymptomatic, pruritus, icteric and terminal stage) were set up for analysing clinical and histopathological features based on the natural course of the disease. The clinical and histopathological findings were similar to the study reported from the United States and European countries. Out of 270 cases examined, 245 (90.7%), had mitochondrial antibodies. Concerning the prognosis 37 of 120 asymptomatic patients developed symptoms and the average symptom-free period in these patients was 28.7 months. Fifty-eight cases were fatal and causes of death were hepatic failure in 27, gastrointestinal bleeding in 20 and others in 11 cases. Patients were subdivided into three groups to elucidate the survival rate in patients with different symptoms. Asymptomatic patients showed almost the same survival rate as the patients with pruritus alone, showing about 50% survival 8 years after the diagnosis, in contrast to jaundiced cases with only 13.6% surviving 8 years after the onset of this symptom.

Expression and localization of basic fibroblast growth factor (bFGF) in the repair process of rat liver injury

BACKGROUND/AIMS To clarify the expression and localization of basic fibroblast growth factor in the repair process of liver injury, acute liver injury was induced by administration of carbon tetrachloride, D-glactosamine hydrochloride, or dimethylnitrosamine to rats. METHODS We measured basic fibroblast growth factor protein in the liver tissue by radioimmunoassay, evaluated the expression of basic fibroblast growth factor mRNA by the reverse transcriptase polymerase chain reaction, and identified basic fibroblast growth factor-positive cells by immunostaining. RESULTS In the carbon tetrachloride injured liver, the basic fibroblast growth factor protein contents began to increase 2 days after administration when liver injury was most marked, and reached a peak after 4 days, decreasing thereafter. In the carbon tetrachloride-injured liver, basic fibroblast growth factor mRNA expression was observed from 12 h after administration, prior to an increase in the protein content. In the D-galactosamine hydrochloride-injured liver, basic fibroblast growth factor protein also increased. On the other hand, in the dimethylnitrosamine-injured liver, the basic fibroblast growth factor protein content decreased 2 days after administration when liver injury was marked, but increased after 7 days. In the regenerating liver after partial hepatectomy, the basic fibroblast growth factor protein content did not increase. Among cell fractions, the Ito cell fraction obtained from the carbon tetrachloride-injured liver after 4 days showed expression of basic fibroblast growth factor mRNA. In cells cultured for 24 h, this fraction was immunopositive for basic fibroblast growth factor. Ito cells in the liver tissue markedly increased in the carbon tetrachloride-injured liver and increased after 7 days in the dimethylnitrosamine-injured liver. CONCLUSIONS This study confirmed basic fibroblast growth factor production in the liver tissue in the repair process of liver injury. Our results suggest that basic fibroblast growth factor is primarily produced in Ito cells, acts on sinusoidal wall cells including Ito cells by the autocrine and paracrine mechanisms, and promotes extracellular matrix production and vascularization, involving the repair process of liver injury.

Effect of branched‐chain amino acids on the composition and cytolytic activity of liver‐associated lymphocytes in rats

Background : Although branched‐chain aminoacids (BCAA) are reported to be effective in prolongation of the mean survival time of patients with liver cirrhosis, it is not clear whether BCAA could influence the immune function in those patients.

Evaluation of transcatheter arterial embolization with epirubicin-lipiodol emulsion for hepatocellular carcinoma*

SummaryA total of 18 patients with hepatocellular carcinoma (HCC) were treated by transcatheter arterial embolization (TAE) with a 4′-epi-doxorubicin (EDX)-lipiodol emulsion. Infusion of the EDX-lipiodol emulsion (EDX-L) via the hepatic artery was followed by the injection of gelatin sponge in 12 cases. The response and survival of these 12 patients following EDX-L treatment were compared with those of 42 subjects treated with a doxorubicinlipiodol emulsion (DX-L) and those of 23 patients treated by TAE with gelatin sponge (GS) only. In the group treated with EDX-L, nine cases were AFP-positive in sera and four showed a decrease in serum AFP values to less than 10% of the pretreatment level. Seven cases showed a partial response, and nine cases showed no change in the size of the tumor. In the group treated with EDX-L, nine cases are alive, and the oldest has survived for more than 431 days since the treatment. The half-year survival value was 57%, and the 1-year survival value was 49%. These values did not differ significantly from those calculated for the group treated with DX-L. The 1-year survival value determined for patients treated with a lipiodol emulsion (EDX-L or DX-L) followed by GS was 65%, and the 2-year survival value was 39%. These results rates are significantly better than those obtained in patients treated with GS only (1-year survival, 39%; 2-year survival, 13%).

Low plasma levels of docosahexaenoic acid in patients with liver cirrhosis and its correction with a polyunsaturated fatty acid–enriched soft oil capsule

Plasma levels of docosahexaenoic acid (DHA, C22:6 omega 3) were found to be decreased in 11 patients with alcoholic and non-alcoholic liver cirrhosis depending on the severity of liver damage. In this reduction, we found impaired metabolism of omega-3 long-chain polyunsaturated fatty acids in the cirrhotic liver and poor dietary intake of DHA to involved in the reduction of DHA plasma levels. The deficiency of this fatty acid, which is concentrated in the nervous tissues, may be related to the impaired neural function observed in hepatic encephalopathy of these patients. Oral DHA supplementation was supplied in the form of a polyunsaturated fatty acid-enriched soft oil capsule (omega 3/omega 6 ratio = 0.91, and P/S ratio = 1.87). Twelve capsules per day (containing 408 mg DHA, which corresponds to one-fourth of the DHA content in a normal daily diet) improved the DHA contents in the plasma phospholipid fractions of 5 alcoholic patients with low DHA levels.

Effects of an infusion of branched-chain amino acids on neurophysiological and psychometric testings in cirrhotic patients with mild hepatic encephalopathy

Abstract Psychotropic action of a branched‐chain‐enriched amino acid solution (Aminoleban) was quantitatively and visually examined in six cirrhotic patients with mild hepatic encephalopathy (grades I and II) using electrophysiological and psychometric methods. Neurophysiological effects of the amino acid solution were observed by comparing topographic spectrum analyses of electroencephalography (EEG) before and immediately after an intravenous 3 h infusion of the solution. The delta wave in the frontal region diminished from 61 ± 13 to 12 ± 4% (P < 0.01) and the alpha wave in the occipital region increased from 11 ± 3 to 51 ± 11% (P < 0.01). Latencies of the P3 wave in visual evoked potentials, which were topographically recorded in the occipital region, shortened from 220 ± 32 to 148 ± 19 ms (P < 0.01). Latencies of the P300 wave in event‐related potentials, which were topographically recorded in the centro‐temporal region, shortened from 493 ± 81 to 360 ± 93 ms (P < 0.05). Topographic reaction pattern of P300 was irregular toward the occipital or parietal region in cirrhotic patients. The EEG frequency power spectrum, illustrated by the colour density spectral array of computer‐aided polysomnography analysis, clearly showed a gradual increase of the alpha wave spectrum and a gradual decrease of the delta wave spectrum after initiation of the infusion. These immediate neurophysiological changes were confirmed by improvement of quantitative psychometric tests including number connection test, reaction time to sound, and digit symbol and block design tests of Wechsler Adult Intelligence Scale.

The protective effect of pyrroloquinoline quinone and its derivatives against carbon tetrachloride-induced liver injury of rats

Pyrroloquinoline quinone (PQQ) and its derivative, oxazo pyrroloquinoline (OPQ‐G), protected rats from experimental liver injury induced by carbon tetrachloride (CCl4) in vivo. This effect was observed after an intraperitoneal injection of 5 mg/kg PQQ or OPQ‐G, which was given twice, 10 min and 1 h before CCl4 administration. Pyrroloquinoline quinone protected primary cultured rat hepatocytes from CCl4 toxicity in vitro. This protection was most effective at a concentration of 3 μmol/L PQQ. Pyrroloquinoline quinone derivatives (oxazo pyrroloquinoline, methyl‐thioethyl oxazo pyrroloquinoline and PQQ‐allylester) also protected the hepatocytes from CCl4 toxicity. Pyrroloquinoline quinone and its derivatives inhibited the lucigenin‐enhanced chemiluminescence from isolated hepatocytes initiated by CCl4. These results suggest that eliminating free radicals is one of the protective mechanisms of PQQ and its derivatives against CCl4‐induced liver injury.