Osamu Hashimoto

Kurume University, Куруме, Fukuoka, Japan

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Publications (44)296.12 Total impact

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    ABSTRACT: Preclinical studies in rodent models of chronic liver fibrosis have shown that transplantation of peripheral blood (PB) CD34(+) cells leads to hepatic regeneration and a reduction of liver fibrosis by suppressing hepatic stellate cell activity and increasing matrix metalloproteinase activity. The aim of this study was to examine the safety and clinical efficacy of intrahepatic transplantation of autologous granulocyte-colony stimulating factor (G-CSF)-mobilized PB-CD34(+) cells in patients with decompensated liver cirrhosis. PB-CD34(+) cells were isolated from G-CSF-mobilized apheresis products. Ten patients were treated with G-CSF-mobilized PB-CD34(+) cells (treatment group) and 7 patients were treated with standard medical therapy. For mobilization, patients in the treatment group received subcutaneous injections of 10 μg G-CSF /kg/day for 5 days. The cells were then injected at three different doses (5×10(5) , 1×10(6) and 2×10(6) cells/kg) through the hepatic artery. Thereafter, all patients were followed-up for 24 months. G-CSF treatment and leukapheresis were well tolerated and no serious adverse events were observed. Patients in the treatment group had a significant but transient splenomegaly. After 24 weeks, serum albumin was significantly increased in patients who had received middle- or high-doses of CD34(+) cells compared to baseline. Doppler-US showed a significant increase in hepatic blood flow velocity and blood flow volume after CD34(+) cell therapy. The hepatic vein pressure gradient decreased in 2 patients who received high-dose CD34(+) cells at week 16. CD34(+) cell therapy is feasible, safe and effective in slowing the decline of hepatic reserve function.
    Journal of Gastroenterology and Hepatology 04/2014; · 3.33 Impact Factor
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    ABSTRACT: It is agreed that many of the antitumor effects of (-)-epigallocatechin gallate (EGCG) are mediated by various other effects. We report a new finding, namely, the antiproliferation potential and mechanism of methylated-(3'')-epigallocatechin gallate analog (MethylEGCG) having a stronger anti-oxidation effect than EGCG. MethylEGCG inhibited activity of vascular endothelial growth factor (VEGF)-depended VEGF receptor 2 and p42/44 MAPK, cell proliferation, and tube formation in human umbilical vascular endothelial cells (HUVECs) at 1 μ M. Even low- dose (1.1 mg/kg i.p. 8.3 mg/kg p.o.) administration suppressed tumor growth in xenografted Huh7 hepatoma mice by 50%. CD31 positive cells, visualized in blood vessels, were reduced in tumors by 18%, suggesting high antitumor activity via inhibition of angiogenesis. This study indicated that the modification of the 3'' position methylation of EGCG (MethylEGCG) could reduce cell growth effects at a low concentration in vivo.
    Nutrition and Cancer 09/2013; · 2.70 Impact Factor
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    ABSTRACT: Background and AimIn cirrhosis, sinusoidal endothelial cell injury results in increased endothelin-1 (ET-1) and decreased nitric oxide synthase (NOS) activity, leading to portal hypertension. However, the effects of transplanted endothelial progenitor cells (EPCs) on the cirrhotic liver have not yet been clarified. We investigated whether EPC transplantation reduces portal hypertension. Methods Cirrhotic rats were created by the administration of carbon tetrachloride (CCl4) twice weekly for 10 weeks. From week 7, rat bone marrow-derived EPCs were injected via the tail vein in this model once a week for 4 weeks. Endothelial NOS (eNOS), vascular endothelial growth factor (VEGF) and caveolin expressions were examined by Western blots. Hepatic tissue ET-1 was measured by a radioimmunoassay (RIA). Portal venous pressure, mean aortic pressure, and hepatic blood flow were measured. ResultsEndothelial progenitor cell transplantation reduced liver fibrosis, α-smooth muscle actin-positive cells, caveolin expression, ET-1 concentration and portal venous pressure. EPC transplantation increased hepatic blood flow, protein levels of eNOS and VEGF. Immunohistochemical analyses of eNOS and isolectin B4 demonstrated that the livers of EPC-transplanted animals had markedly increased vascular density, suggesting reconstitution of sinusoidal blood vessels with endothelium. Conclusions Transplantation of EPCs ameliorates vascular dysfunction and portal hypertension, suggesting this treatment may provide a new approach in the therapy of portal hypertension with liver cirrhosis.
    Journal of Gastroenterology and Hepatology 01/2013; 28(1). · 3.33 Impact Factor
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    ABSTRACT: VEGF, EGF, and TGF-α are expressed in hepatocellular carcinomas (HCC) and play a role in its growth. Vandetanib, a multikinase inhibitor, suppresses the phosphorylation of VEGF receptor 2 (VEGFR-2) and EGF receptor (EGFR). The aim of this study was to clarify the antitumor effect of vandetanib in mouse HCCs. We evaluated the effects of vandetanib on proliferation of human umbilical vein endothelial cells (HUVEC) and three hepatoma cell lines, as well as the phosphorylation of VEGFR-2 and EGFR in these cells. Mice were implanted with hepatoma cells subcutaneously or orthotopically in the liver and treated with 50 or 75 mg/kg vandetanib. We analyzed the effects of treatment on tumor cell proliferation and apoptosis, vessel density, phosphorylation of VEGFR-2 and EGFR, and production of VEGF, TGF-α, and EGF in tumor tissues. Adverse events on vandetanib administration were also investigated. Vandetanib suppressed phosphorylation of VEGFR-2 in HUVECs and EGFR in hepatoma cells and inhibited cell proliferation. In tumor-bearing mice, vandetanib suppressed phosphorylation of VEGFR-2 and EGFR in tumor tissues, significantly reduced tumor vessel density, enhanced tumor cell apoptosis, suppressed tumor growth, improved survival, reduced number of intrahepatic metastases, and upregulated VEGF, TGF-α, and EGF in tumor tissues. Treatment with vandetanib was not associated with serious adverse events, including alanine aminotransferase abnormality, bone marrow suppression, or body weight loss. The antitumor effects of vandetanib in mice suggest that it is a potentially suitable and safe chemotherapeutic agent for HCCs.
    Clinical Cancer Research 05/2012; 18(14):3924-33. · 7.84 Impact Factor
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    ABSTRACT:   Using the dimethylnitrosamine (DMN) rat model of induced fibrosis, we investigated whether transfer of in vitro-expanded endothelial progenitor cells (EPCs) could reconstitute liver tissue and protect against liver fibrosis.   Low-density, adherent, rat bone marrow-derived mononuclear cells were cultured for one week in medium supporting the growth of chemokine (C-X-C motif) receptor 4 (CXCR4)-positive EPCs that were used for transplantation. Test rats were treated with weekly intraperitoneal injections of DMN over a period of 4 weeks. During that period, the rats were also transplanted weekly with in vivo-expanded EPCs.   Transplanted CXCR4-positive expanded EPCs entered around the portal tracts, fibrous septa and hepatic sinusoids, locations at which stromal cell-derived factor 1 (SDF-1), a ligand attracting CXCR4-positive cells, was expressed nearby. In EPC-transplanted rats, we observed suppression of liver fibrogenesis, reduced deposition of type I collagen and fibronectin, fewer α-smooth muscle actin-positive cells and lower expression of transforming growth factor (TGF)-β. The expression of growth factors promoting hepatic regeneration (hepatocyte growth factor, transforming growth factor-α (TGF-α), epidermal growth factor and vascular endothelial growth factor) was significantly increased in EPC-transplanted rats, resulting in hepatocyte proliferation. Immunohistochemical analyses of eNOS and isolectin B4 demonstrated that the livers of EPC-transplanted animals had markedly increased vascular density, suggesting reconstitution of sinusoidal blood vessels with endothelium. Liver function tests of transaminase, total bilirubin, total protein and albumin demonstrated that normal levels were maintained in EPC-transplanted rats.   EPC transplantation effectively promotes the remodelling of tissues damaged by liver fibrosis; it can also reconstitute sinusoids in chronic liver injury.
    European Journal of Clinical Investigation 12/2011; 42(7):717-28. · 3.37 Impact Factor
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    ABSTRACT: The drug delivery system to tumors is a critical factor in upregulating the effect of anticancer drugs and reducing adverse events. Recent studies indicated selective migration of bone marrow-derived endothelial progenitor cells (EPC) into tumor tissues. Cytosine deaminase (CD) transforms nontoxic 5-fluorocytosine (5-FC) into the highly toxic 5-fluorouracil (5-FU). We investigated the antitumor effect of a new CD/5-FC system with CD cDNA transfected EPC for hepatocellular carcinoma (HCC) in mice. We used human hepatoma cell lines (HuH-7, HLF, HAK1-B, KYN-2, KIM-1) and a rat EPC cell line (TR-BME-2). Escherichia coli CD cDNA was transfected into TR-BME-2 (CD-TR-BME). The inhibitory effect of 5-FU on the proliferation of hepatoma cell lines and the inhibitory effect of 5-FU secreted by CD-TR-BME and 5-FC on the proliferation of co-cultured hepatoma cells were evaluated by a tetrazolium-based assay. In mouse subcutaneous xenograft models of KYN-2 and HuH-7, CD-TR-BME was transplanted intravenously followed by 5-FC injection intraperitoneally. HuH-7 cells were the most sensitive to 5-FU and KYN-2 cells were the most resistant. CD-TR-BME secreted 5-FU and inhibited HuH-7 proliferation in a 5-FC dose-dependent manner. CD-TR-BME were recruited into the tumor tissues and some were incorporated into tumor vessels. Tumor growth of HuH-7 was significantly suppressed during 5-FC administration. No bodyweight loss, ALT abnormality or bone marrow suppression was observed. These findings suggest that our new CD/5-FC system with CD cDNA transfected EPC could be an effective and safe treatment for suppression of 5-FU-sensitive HCC growth.
    Cancer Science 12/2011; 103(3):542-8. · 3.48 Impact Factor
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    ABSTRACT: We investigated whether transplantation of purified human peripheral blood CD34(+) cells could reduce established liver fibrosis and up-regulate therapeutic regeneration. Human peripheral blood CD34(+) cells were isolated from total mononuclear cells of healthy volunteers by magnetic cell sorting. Recipient nude rats were injected intraperitoneally with carbon tetrachloride (CCl(4)) twice weekly for 3 weeks before single administration of CD34(+) cells. CCl(4) was then re-administered twice weekly for 3 more weeks, and the nude rats were sacrificed. Saline (control group), 1 × 10(5) (low-dose group), 5 × 10(5) (middle-dose group), or 2 × 10(6) (high-dose group) CD34(+) cells/kg body weight were intrasplenically transplanted after CCl(4) treatment for 3 weeks. Reverse transcriptase-polymerase chain reaction analysis of the freshly isolated CD34(+) cells revealed the expression of CD31, keratin19, α-smooth muscle actin (α-SMA), and epithelial growth factor, but not other liver related markers. The transplanted cells differentiated into vascular and sinusoidal endothelial cells, and vascular smooth muscle cells. CD34(+) cell transplantation reduced liver fibrosis in a dose-dependent fashion, with decreased collagen type-I and α-SMA-positive cells after 6 weeks of CCl(4) treatment by Mallory's Azan and immunohistochemical staining. Gelatin zymography showed that the expression levels of active matrix metalloproteinase-2 and -9 in CD34(+) cell transplanted livers were significantly stronger than those in saline-infused livers. In recipients of high-doses of CD34(+) cells, the number of PCNA-positive hepatocyte increased 6 weeks after CCl(4) treatment compared with saline-infused livers. We conclude that human peripheral blood CD34(+) cell transplantation halts established liver fibrosis and promotes hepatic regeneration in CCl(4)-induced chronic liver injury.
    Journal of Cellular Physiology 06/2011; 227(4):1538-52. · 4.22 Impact Factor
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    ABSTRACT: Metronomic chemotherapy involves frequent, regular administration of cytotoxic drugs at nontoxic doses, usually without prolonged breaks. We investigated the therapeutic efficacies of metronomic S-1, an oral 5-fluorouracil prodrug, and vandetanib, an epidermal growth factor receptor and vascular endothelial growth factor (VEGF) receptor tyrosine kinase inhibitor, in models of hepatocellular carcinoma (HCC). We compared anti-HCC effects and toxicity in the six treatment groups: control (untreated), maximum tolerated dose (MTD) S-1, metronomic S-1, vandetanib, MTD S-1 with vandetanib, and metronomic S-1 with vandetanib. Tumor microvessel density (MVD) and tumor apoptosis were evaluated by immunohistochemistry. The expression of VEGF and thrombospondin-1, an endogenous inhibitor of angiogenesis, was analyzed by Western blot. Metronomic S-1 significantly inhibited tumor growth, which was enhanced by combination with vandetanib. With respect to toxicities, MTD S-1 caused severe body weight loss and myelosuppression, whereas metronomic S-1 did not cause any overt toxicities. Moreover, metronomic S-1 or metronomic S-1 with vandetanib prolonged survival, the latter treatment providing the greatest benefit. Metronomic S-1 and metronomic S-1 with vandetanib decreased MVDs and increased apoptosis in tumor tissues. The expression of VEGF in tumor tissues was upregulated by vandetanib and metronomic S-1 with vandetanib, whereas the expression of thrombospondin-1 was upregulated by metronomic S-1 and metronomic S-1 with vandetanib. Metronomic S-1 with an antiangiogenic agent seems to be an effective and safe therapeutic strategy for HCC.
    Neoplasia (New York, N.Y.) 03/2011; 13(3):187-97. · 5.48 Impact Factor
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    ABSTRACT: We examined whether or not epigallocatechin-3-gallate (EGCG) improves liver injury of nonalcoholic steatohepatitis (NASH) model mice expressing nuclear sterol regulatory element-binding protein 1c (nSREBP-1c) in adipose tissue. nSREBP-1c transgenic C57BL6 mice aged 30 weeks were divided into group 1 (no treatment), group 2 (ascorbic acid alone), group 3 (ascorbic acid and 0.05% EGCG), and group 4 (ascorbic acid and 0.1% EGCG). At 42 weeks, we performed measurement of liver weight to body weight, biochemical assays, morphometry of liver specimens, immunohistochemistry for 8-hydro-2'-deoxyguanosine (8-OhdG), and Western blotting for insulin and TNF-alpha signalings. Ratio of liver weight to body weight in the high dose EGCG-treated group (group 4) was significantly lower than those of groups 1 and 2 (p<0.05 and <0.01, respectively). Blood ALT, glucose, total cholesterol, and triglyceride levels of group 4 were significantly low compared with those of the EGCG-non-treated group (groups 1 and 2) (p<0.05, respectively). The degrees of steatosis, inflammation, ballooning hepatocytes and Mallory-Denk bodies in group 4 significantly improved compared with those in other groups (p<0.05, respectively). The 8-OhdG immunolocalization in liver tissues of the group 4 obviously decreased compared with those of groups 2 and 3. For Western blotting, the expressions of insulin receptor substrate-1 (IRS-1) and phosphorylated IRS-1 (pIRS-1) in liver tissues of group 4 increased compared with those of groups 2 and 3. On the other hand, the expressions of pAkt, pIKKbeta and pNF-kappaB decreased compared with those of groups 2 and 3. From these results, EGCG reduces inflammation, insulin resistance and oxidative stress, and suppresses liver injury in nSREBP-1c transgenic mice.
    International Journal of Molecular Medicine 07/2009; 24(1):17-22. · 1.96 Impact Factor
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    ABSTRACT: We investigated whether endothelial progenitor cell (EPC) transplantation could reduce established liver fibrosis and promote hepatic regeneration by isolating rat EPCs from bone marrow cells. Recipient rats were injected intraperitoneally with carbon tetrachloride (CCl(4)) twice weekly for 6 weeks before initial administration of EPCs. CCl(4) was then readministered twice weekly for 4 more weeks, and EPC transplantation was carried out for these same 4 weeks. At 7 days in culture, the cells expressed Thy-1, CD31, CD133, Flt-1, Flk-1, and Tie-2, suggesting an immature endothelial lineage. Immunohistochemical analyses showed fluorescent-labeled, transplantation EPCs were incorporated into the portal tracts and fibrous septa. Single and multiple EPC transplantation rats had reduced liver fibrosis, with decreased alpha2-(I)-procollagen, fibronectin, transforming growth factor-beta, and alpha-smooth muscle actin-positive cells. Film in situ zymographic analysis revealed strong gelatinolytic activity in the periportal area, in accordance with EPC location. Real-time polymerase chain reaction analysis of multiple EPC-transplantation livers showed significantly increased messenger RNA levels of matrix metalloproteinase (MMP)-2, -9 and -13, whereas tissue inhibitor of metalloproteinase-1 expression was significantly reduced. Expression of hepatocyte growth factor, transforming growth factor-alpha, epidermal growth factor, and vascular endothelial growth factor was increased in multiple EPC-transplantation livers, while hepatocyte proliferation increased. Transaminase, total bilirubin, total protein, and albumin levels were maintained in EPC-transplantation rats, significantly improving survival rates. We conclude that single or repeated EPC transplantation halts established liver fibrosis in rats by suppressing activated hepatic stellate cells, increasing matrix metalloproteinase activity, and regulating hepatocyte proliferation.
    Gastroenterology 08/2007; 133(1):91-107.e1. · 12.82 Impact Factor
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    ABSTRACT: Recent studies indicate that kringle 1-5 has a potent and specific antiangiogenic activity. Here, we investigated the antitumor effect of kringle 1-5 gene transfer on hepatocellular carcinoma in mice. The inhibitory effect of kringle 1-5 protein on proliferation of bovine capillary endothelial cells was evaluated by a tetrazolium-based assay. To study tumor growth, intrahepatic metastasis, and survival, liposome/kringle 1-5 complementary DNA complexes were injected intravenously in nude mice preimplanted with 1 of 3 hepatoma cell lines into the liver. Production of kringle 1-5 was tested by immunohistochemistry and Western blotting. Intratumoral vessel density was quantified. Expression of vascular endothelial growth factor, angiopoietin-1, and angiopoietin-2 in tumors was examined by Western blotting. Serum alanine aminotransferase and alpha-fetoprotein levels and body weights were measured. Proliferation of bovine capillary endothelial cells was inhibited by purified kringle 1-5 in a dose-dependent manner. Gene transfer of kringle 1-5 caused a significant reduction in vessel density with suppression of tumor growth of the 3 hepatoma cell lines and serum alpha-fetoprotein levels, prolonged the survival period, and reduced the number of intrahepatic metastases. Among the analyzed angiogenic factors, kringle 1-5 reduced angiopoietin-2 expression levels. Expression of kringle 1-5 protein was detected on hepatoma cells and hepatocytes in the liver. However, it did not alter serum alanine aminotransferase levels and body weights, suggesting kringle 1-5 lacks severe side effects. Antiangiogenic gene therapy with kringle 1-5 complementary DNA is a promising safe and effective strategy for suppression of growth of hepatocellular carcinoma.
    Gastroenterology 05/2006; 130(4):1301-10. · 12.82 Impact Factor
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    ABSTRACT: Wee1 kinase plays a critical role in maintaining G2 arrest through its inhibitory phosphorylation of cdc2. In previous reports, a pyridopyrimidine molecule PD0166285 was identified to inhibit Wee1 activity at nanomolar concentrations. This G2 checkpoint abrogation by PD0166285 was demonstrated to kill cancer cells, there at a toxic highest dose of 0.5 muM in some cell lines for exposure periods of no longer than 6 hours. The deregulated cell cycle progression may have ultimately damaged the cancer cells. We herein report one of the mechanism by which PD0166285 leads to cell death in the B16 mouse melanoma cell line. Tumor cell proliferation was determined by counting cell numbers. Cell cycle distribution was determined by flow cytometry. Morphogenesis analysis such as microtubule stabilization, Wee1 distribution, and cyclin B location were observed by immunofluorescence confocal microscopy. An immunoblot analysis of cdc2-Tyr15, cyclin D, E, p16, 21, 27, and Rb. A real-time PCR of the mRNA of cyclin D were completed. In our experiment, B16 cells also dramatically abrogated the G2 checkpoint and were found to arrest in the early G1 phase by treatment with 0.5 muM for 4 hours observed by flow cytometry. Cyclin D mRNA decreased within 4 hours observed by Real-time PCR. Rb was dephosphrylated for 24 hours. However, B16 cells did not undergo cell death after 0.5 muM treatment for 24 hours. Immnofluoscence microscopy showed that the cells become round and small in the morphogenesis. More interesting phenomena were that microtubule stabilization was blocked, and Wee1 distribution was restricted after treatment for 4 hours. We analyzed the effect of Wee1 inhibitor PD0166285 described first by Wang in the G2 transition in the B16 melanoma cell line. The inhibitor PD0166285 abrogated G2/M checkpoint inducing early cell division. Moreover, we found that the treatment of cells with the inhibitor is related to microtubule stabilization and decrease in cyclin D transcription. These effects together suggest that Wee1 inhibitor may thus be a potentially useful anti-cancer therapy.
    BMC Cancer 02/2006; 6:292. · 3.33 Impact Factor
  • Journal of Hepatology - J HEPATOL. 01/2006; 44.
  • Journal of Hepatology - J HEPATOL. 01/2006; 44.
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    ABSTRACT: A 47-year-old woman with primary biliary cirrhosis and scleroderma was examined at our hospital for a 1-week history of non-resolving fever, arthralgia, myalgia, muscle weakness and fatigue. A diagnosis of systemic lupus erythematosus was made based on arthralgia, low leukocyte count, low lymphocyte count, low serum concentration of complements, positive anti-nuclear antibody and positive anti-double-strand-DNA antibody. She was negative for anti-U1RNP antibody, but positive for anti-Jo1 antibody, and her initial serum concentration of creatine phosphokinase was elevated. We diagnosed her as having overlap syndrome with scleroderma, systemic lupus erythematosus and possible polymyositis associated with primary biliary cirrhosis. Prednisolone rapidly improved her symptoms. Lobulated leukocytes were observed in her peripheral blood specimen. She was positive for anti-HTLV-1 antibody, but Southern blot hybridization did not confirm monoclonal integration of HTLV-I proviral DNA in her peripheral blood. This suggests the possibility of a relationship between HTLV-1 infection and various autoimmune disorders including primary biliary cirrhosis.
    Hepatology Research 03/2005; 31(2):116-9. · 2.07 Impact Factor
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    ABSTRACT: To determine the effects of dominant-negative TGF-beta receptor expression during liver regeneration in rats with dimethylnitrosamine (DMN)-induced liver injury. Rats were first treated with DMN for 3 weeks, and then intravenously injected once with AdTbeta-TR, AdLacZ, or saline. Serial changes in hepatocyte proliferation and apoptosis were evaluated by immunohistochemistry using anti-Ki67 antibody, and TUNEL staining, respectively. The mRNA expression of regeneration factors (HGF, TGF-alpha, EGF, and IGF-I) and IL-6 were evaluated by real-time PCR and northern blotting. Anti-TGF-beta molecular intervention up-regulated hepatocyte proliferation and inhibited apoptosis. In the AdTbeta-TR-treated rats, EGF and IGF-I mRNA expression levels were significantly increased at day 1 and remained high for 3 days after gene transfer; TGF-alpha mRNA expression levels were significantly increased at 2 to 5 days after gene transfer; HGF mRNA expression levels were significantly up-regulated at day 2 only after gene transfer; while IL-6 mRNA expression level tended to increase at day 1, but decreased thereafter. In rats with DMN-induced liver injury, anti-TGF-beta molecular intervention therapy stimulates proliferation and reduces apoptosis of hepatocytes, and also up-regulates the transcription of various growth factors.
    Journal of Hepatology 01/2005; 41(6):974-82. · 9.86 Impact Factor
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    ABSTRACT: Hepatocellular carcinoma (HCC) is a highly vascular tumor. Angiopoietin-1 and Angiopoietin-2 have been shown to be involved in tumor angiogenesis. We investigated the expression of Angiopoietin-1 and Angiopoietin-2 in HCC. The expression of Angiopoietin-1 and Angiopoietin-2 mRNAs in cultured hepatoma cells under hypoxic conditions and in HCC and noncancerous liver tissue was evaluated by real-time PCR. The expression of Angiopoietin-1, Angiopoietin-2, and their receptor Tie-2 in HCC was assessed by immunohistochemistry. The changes in Angiopoietin-1 and Angiopoietin-2 expression were evaluated in relation to tumor differentiation and changes in tumor vascularity. Hypoxic conditions did not up-regulate the expression of Angiopoietin-1 and Angiopoietin-2 mRNAs in hepatoma cells. Increased expression of Angiopoietin-1 and Angiopoietin-2 mRNAs was detected in HCC. Angiopoietin-1 and Angiopoietin-2 were detected in hepatoma cells, hepatic stellate cells, and smooth muscle cells, whereas Tie-2 was detected in endothelial cells, hepatic stellate cells and smooth muscle cells. Increased expression of Angiopoietin-2 and Angiopoietin-2 mRNA was associated with tumor dedifferentiation. The expression of Angiopoietin-1 and Angiopoietin-2 correlated with HCC vascularity. Our findings indicate that the increased expression of Angiopoietin-1 and Angiopoietin-2 play a critical role in the process of vascular development in HCC.
    Journal of Hepatology 06/2004; 40(5):799-807. · 9.86 Impact Factor
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    ABSTRACT: Between March 1994 and March 1996 we studied transmission routes and clinical courses in eight patients with sporadic acute hepatitis C (two men, six women). Of the eight patients, three were treated for another illness 1–2 months before the onset of hepatitis, one was a parenteral drug abuser, one had an accidental needlestick injury and two had sexual contact with a partner with chronic hepatitis C virus (HCV) infection. Clinical courses included four women whose HCV RNA and alanine aminotransferase (ALT) became persistently negative without treatment, and four men and two women with the same results following interferon (IFN) treatment. It is thought that IFN therapy may prevent the progression to chronic liver disease. Results from this study might be useful in the future management of patients with sporadic acute hepatitis C.
    Journal of Viral Hepatitis 11/2003; 4(4):273 - 278. · 3.08 Impact Factor
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    ABSTRACT: Transforming growth factor beta1 (TGF beta 1)-induced G2 arrest was observed when a proliferation inhibitory function of the retinoblastoma protein (Rb) was compromised, but the mechanism underlying the G2 arrest was poorly characterized compared with that of G1 arrest. In the present study, we characterized G2 arrest induced by TGF beta1 (1 ng/mL) in the Rb-negative hepatoma cell line (Hep3B) and compared with G1 arrest in the Rb-positive hepatoma cell line (Huh7). Activities of cyclin-dependent kinases (CDK) 2 and cell division cycle (CDC) 2 were markedly decreased at 24 h, the time when cell-cycle arrest became apparent in both cell lines. However, considerable amounts of inactive CDC2-cyclinB1 complexes were present in the nucleus of G2-arrested Hep3B but were not present in G1-arrested Huh7. The inhibitory phosphorylation of CDC2 on Tyr-15 was significantly elevated at 12-24 h, and its levels gradually declined during G2 arrest in Hep3B. In particular, augmentation of CDK inhibitors p21cip1 and p27kip1 and Wee1 kinase and diminution of CDC25C phosphatase coincided with induced Tyr-15 phosphorylation and inhibition of CDC2. Wee1 in Hep3B was unstable and was degraded in a proteasome-dependent manner, but it became substantially stabilized within 6 h of TGF beta 1 treatment. Moreover, a Wee1 inhibitor, PD0166285, abrogated the TGF beta 1-induced G2 arrest in Hep3B. These findings suggest that TGF beta 1 induced G2 arrest in Hep3B at least in part through stabilization of Wee1 and subsequent increase in Tyr-15 phosphorylation and inhibition of CDC2.
    Molecular Carcinogenesis 05/2003; 36(4):171-82. · 4.27 Impact Factor
  • Journal of Hepatology - J HEPATOL. 01/2003; 38:79-79.

Publication Stats

982 Citations
296.12 Total Impact Points

Institutions

  • 1997–2014
    • Kurume University
      • • Research Center for Innovative Cancer Therapy
      • • Division of Gastroenterology
      Куруме, Fukuoka, Japan
  • 2003
    • Social Insurance Chukyo Hospital
      Nagoya, Aichi, Japan
  • 1998–2002
    • Kyushu University
      • Medical Institute of Bioregulation - MIB Hospital
      Fukuoka-shi, Fukuoka-ken, Japan