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Biomedical subjects

Y Kaneda

Publications and source records attributed to Y Kaneda.

At least 181 records · Page 10Linked to original sources
PubMed1999

Regression of hepatocellular carcinoma in vitro and in vivo by radiosensitizing suicide gene therapy under the inducible and spatial control of radiation.

To improve the efficacy and selectivity of gene therapy for hepatocellular carcinoma (HCC), we designed a strategy for suicide gene therapy in conjunction with radiation therapy using an HVJ-liposome vector system. The radio-inducible suicide gene was constructed by insertion of the early growth response gene 1 (Egr-1) promoter upstream of the HSV-tk gene (EGF-tk). First, to test the tumor specificity of Egr-1, RT-PCR and immunohistochemistry were performed. The Egr-1 gene was highly expressed in HCC compared with normal liver, where expression was barely detectable. Next, radiation-inducible activity of the Egr-1 promoter was examined in primary cultured normal hepatocytes and human hepatoma cell lines Huh7, HepG2, and PLC/PRF/5 by luciferase assay as a reporter gene system. Egr-1 promoter activity was markedly increased in hepatoma cell lines in a radiation dose-dependent manner, with maximum activation (15- to 28-fold) 12 hr after irradiation. In contrast, only a twofold increase in activation was noted in normal hepatocytes. An in vitro gene therapy experiment showed that EGR-tk-transduced hepatoma cells became highly sensitive to ganciclovir (GCV) after irradiation, but not without irradiation. GCV with or without irradiation did not show any cytotoxic effects against control gene-transfected cells. In addition, a "radiosensitization effect" was also demonstrated by combination therapy with the HSV-tk/GCV system and irradiation. To examine the efficacy of this EGR-tk/GCV gene therapy in vivo, xenografted liver tumors in nude mice were targeted using the HVJ-liposome vector system. EGR-tk-transfected tumors regressed significantly after a combination therapy of irradiation and GCV in all mice (n = 8), and almost disappeared in 3 weeks without any side effects. In comparison, tumors continued to grow in all mice (n = 8 in each group) treated by transfer of EGR-tk followed by either irradiation without GCV or GCV without irradiation. Our data indicate that HSV-tk gene therapy under the control of a radioinducible promoter is effective, and might be selective for hepatoma cells because of its inducible and radiosensitive capacity after radiation exposure as well as its tumor-specific activation.

Aged↗
PubMed1999

Transcription factor decoy to study the molecular mechanism of negative regulation of renin gene expression in the liver in vivo.

Renin is synthesized in high quantities in the juxtaglomerular cells of the kidney, but little or none is synthesized in the liver. Our previous in vitro and biochemical studies have demonstrated that tissue-specific expression of the mouse renin gene is regulated by the specific interaction between negative regulatory element (NRE) in the 5'-flanking region of the renin gene and NRE binding protein (NREB). In this study, we examined the hypothesis that this interaction between the NRE in the promoter region of the rat renin gene and the NREB in the liver contributes to the suppressed renin gene expression in this tissue in vivo. We used in vivo transfection of NRE transcription factor decoy (TFD) double-stranded oligonucleotide into the rat liver via portal vein infusion. A gel mobility shift assay showed that transfected NRE TFD blocked endogenous NREB binding with the rat renin gene. This resulted in enhanced hepatic renin mRNA expression, immunohistochemical detection of renin in the liver, and consequently, increased plasma renin concentration. Taken together, these results document the importance of NREB in the inhibition of renin gene expression in rat liver in vivo and suggest the possibility of in vivo renin gene modulation by the TFD approach.

Animals↗
PubMed1999

Molecular design of conjugated tumor necrosis factor-alpha: synthesis and characteristics of polyvinyl pyrrolidone modified tumor necrosis factor-alpha.

We conjugated tumor necrosis factor-alpha (TNF-alpha) with the synthetic polymeric modifier polyvinyl pyrrolidone (PVP) to facilitate its clinical use for anti-tumor therapy. TNF-alpha was chemically conjugated with the terminal carboxyl-bearing PVP at one end of its main chain, which was radically polymerized via the formation of an amide bond between the lysine amino groups of TNF-alpha and carboxyl group of PVP. In vitro specific bioactivity of PVP-conjugated TNF-alpha (PVP-TNF-alpha) relative to that of native TNF-alpha gradually decreased with increases in the degree of PVP attachment. In contrast, PVP-TNF-alpha in which 40% of TNF-alpha lysine residues were coupled with PVP (MPVP-TNF-alpha) exhibited the highest anti-tumor activity among the conjugated derivatives examined. MPVP-TNF-alpha had more than 200-fold higher anti-tumor efficacy than native TNF-alpha, and the anti-tumor activity of MPVP- TNF-alpha was more than 5-fold stronger than that MPEG- TNF-alpha which had the highest anti-tumor activity among PEG-conjugated TNF-alphas examined. Additionally, a high dose of native TNF-alpha induced toxic side-effects such as body weight reduction, piloerection and tissue inflammation, while no side effects were observed following i.v. administration of MPVP-TNF-alpha. The plasma half-life of MPVP-TNF-alpha (360 min) was about 80 and 3-fold longer than those of native TNF-alpha (4.6 min) and MPEG-TNF-alpha (122 min), respectively. These results suggested that PVP is a useful polymeric modifier for increasing the anti-tumor activity of PVP.

Animals↗
PubMed1999

Ribosome-associated protein LBP/p40 binds to S21 protein of 40S ribosome: analysis using a yeast two-hybrid system.

The ribosome-associated protein LBP/p40, which was originally named after "laminin binding protein precursor p40," is distributed on the cell surface as laminin binding protein p67 (LBP/p67), in the nucleus, and on 40S ribosomes. In a broad range of eukaryotes, the localization of LBP/p40 on the 40S ribosome is well conserved. Two yeast homologs of LBP/p40 are believed to be essential for cell viability and each gene product probably corresponds to the assembly and/or stability of the 40S ribosomal subunit. The precise role of LBP/p40 in translation, however, remains to be elucidated, especially in higher eukaryotes. In this report, we used a yeast two-hybrid screening method to isolate molecules associated with human LBP/p40 protein on ribosomes. We found that the 40S ribosomal protein S21 was tightly bound with LBP/p40 in this yeast two-hybrid system and in in vitro analysis. Further, we discovered that the association required a broad region of the LBP/p40 amino acid sequence, which corresponds to the highly conserved region of LBP/p40 homologs among eukaryotes.

5' Untranslated Regions↗
PubMed1999

Bioconjugation of laminin peptide YIGSR with poly(styrene co-maleic acid) increases its antimetastatic effect on lung metastasis of B16-BL6 melanoma cells.

A comb-shaped polymeric modifier, SMA [poly(styrene comaleic anhydride)], which binds to plasma albumin in blood was used to modify the synthetic cell-adhesive laminin peptide YIGSR, and its inhibitory effect on experimental lung metastasis of B16-BL6 melanoma cells was examined. YIGSR was chemically conjugated with SMA via formation of an amide bond between the N-terminal amino group of YIGSR and the carboxyl anhydride of SMA. The antimetastatic effect of SMA-conjugated YIGSR was approximately 50-fold greater than that of native YIGSR. When injected intravenously, SMA-YIGSR showed a 10-fold longer plasma half-life than native YIGSR in vivo. In addition, SMA-YIGSR had the same binding affinity to plasma albumin as SMA, while native YIGSR did not bind to albumin. These findings suggested that the enhanced antimetastatic effect of SMA-YIGSR may be due to its prolonged plasma half-life by binding to plasma albumin, and that bioconjugation of in vivo unstable peptides with SMA may facilitate their therapeutic use.

Animals↗
PubMed1999

Suppressed severity of collagen-induced arthritis by in vivo transfection of nuclear factor kappaB decoy oligodeoxynucleotides as a gene therapy.

OBJECTIVE: In both rheumatoid arthritis and collagen-induced arthritis (CIA), the nuclear factor kappaB (NF-kappaB) transcription factor plays a pivotal role in the coordinated transactivation of many cytokines related to pathogenesis. This study investigated whether synthetic double-stranded DNA that show a high affinity for NF-kappaB could be introduced in vivo as "decoy" cis elements to bind the transcription factor and block the activation of such proinflammatory cytokine genes as interleukin-1 (IL-1) and tumor necrosis factor alpha (TNFalpha), and thus suppress the severity of joint destruction. METHODS: NF-kappaB decoy oligonucleotides (ODN) were introduced by an intraarticular injection into the bilateral hind ankle joints of CIA rats using the hemagglutinating virus of Japan (HVJ)-liposome method. Joint destruction was evaluated by histology and radiography. IL-1 and TNFalpha levels were assessed by enzyme-linked immunosorbent assay and Northern blot analysis. RESULTS: Using the HVJ-liposome method, the presence of fluorescein isothiocyanate-labeled ODN in the synovium was confirmed until 28 days after intraarticular injection. In vivo transfection of NF-kappaB decoy ODN by an intraarticular injection into CIA rats decreased the severity of hind-paw swelling. Histologic and radiographic studies showed a marked suppression of joint destruction treated by NF-kappaB decoy ODN transfection. This treatment method also suppressed the production of IL-1 and TNFalpha in the synovium of arthritic joints. CONCLUSION: The present results demonstrate that administration of NF-kappaB decoy ODN in arthritic joints of rats with CIA led to an amelioration of arthritis. These findings suggest that intraarticular transfection of NF-kappaB decoy ODN may provide a useful therapeutic approach for the treatment of inflammatory arthritis.

Animals↗
PubMed1999

Subjective symptoms and prognosis after lung volume reduction surgery in patients with severe pulmonary emphysema.

Lung volume reduction surgery improves symptoms in patients with severe pulmonary emphysema, but patients are not always satisfied surgical results. Our purpose was to determine the profiles and prognosis of unsatisfactory cases of lung volume reduction surgery. A total of 58 patients with advanced symptomatic emphysema underwent thoracoscopic volume reduction of emphysematous lung tissue. Patients subjectively evaluated their condition 3 months after surgery as "better," "same," or "worse" than before surgery. Of these, 30 evaluated themselves as "better" (58%), 17 as the "same" (33%), and 4 (8%) as "Worse." Most patients with vital capacity (VC) exceeding 2,000 mL (percentage of vital capacity for the predicted value (%VC) of > 60%) with upper-lobe-predominant and centrilobular emphysema were satisfied with surgical results. All patients with lower-lobe-predominant or whole-lung panacinar emphysema evaluated their results as "worse." Six late deaths occurred due to pulmonary infection (3), respiratory failure (2), and an unknown sudden cause (1), with most of these patients having preoperative low VC and high postoperative partial carbon dioxide pressure in the arterial blood (PaCO2).

Aged↗
PubMed1999

Protection of hamsters from amebic liver abscess formation by a monoclonal antibody to a 150-kDa surface lectin of Entamoeba histolytica.

We examined the effects of passive immunization with a monoclonal antibody (EH3015) that recognizes a 150-kDa surface lectin of Entamoeba histolytica on amebic liver-abscess formation in hamsters. The hamsters were inoculated i.p with 0.1, 1.0, or 10 mg of EH3015 at 24 h prior to an intrahepatic challenge with 10(5) trophozoites of E. histolytica. In hamsters treated with 1.0 and 10 mg of EH3015 the incidence of liver abscesses was significantly reduced. These results demonstrate that monoclonal antibody EH3015 can prevent the development of amebic liver abscesses and that the 150-kDa lectin may be a protective antigen on the surface of E. histolytica.

Animals↗
PubMed1999

Gene transfection of hepatocyte growth factor attenuates reperfusion injury in the heart.

BACKGROUND: Hepatocyte growth factor (HGF), a ligand for the c-Met receptor tyrosine kinase, plays a role as organotrophic factor for regeneration of various organs. HGF has an angiogenic activity and exhibits a potent antiapoptotic activity in several types of cells. Although HGF and the c-Met/HGF receptor are expressed in the heart, the role of HGF in the heart has remained unknown. METHODS: After we analyzed changes in expression of endogenous HGF and c-Met mRNA levels in the rat left ventricle after myocardial infarction, the human HGF gene in hemagglutinating virus of Japan (HVJ)-liposome was transfected into the normal whole rat heart. Three days after transfection, the heart was subjected to global warm ischemia and subsequent reperfusion, followed by assessment of its cardiac functions. RESULTS: Both HGF and c-Met/HGF receptor mRNAs were expressed in adult rat heart, and c-Met/HGF receptor mRNA was upregulated in response to myocardial infarction. HGF-transfected heart showed significant increase of human HGF protein level in the heart. Cardiac functions in terms of the left ventricular developed pressure, maximum dp/dt, and pressure rate product in hearts with HGF gene transfection were significantly superior to those in control hearts. In addition, leakage of creatine phosphokinase in the coronary artery effluent in hearts with HGF gene transfection was significantly lower than that in control hearts. CONCLUSIONS: These data indicated that both HGF and c-Met/HGF receptor mRNAs were upregulated in response to myocardial ischemic injury, and that HGF is likely to have a cytoprotective effect on cardiac tissue, presumably through the c-Met/HGF receptor.

Animals↗
PubMed1999

Myocardial protection with endogenous overexpression of manganese superoxide dismutase.

BACKGROUND: Superoxide dismutase (SOD) is a potent candidate for myocardial protection against ischemia-reperfusion injury; however, its clinical significance by means of exogenous administration remains controversial. METHODS: To determine a role of endogenously overexpressed manganese SOD (Mn-SOD) in myocardial tolerance, rat hearts were transfected with Mn-SOD gene (group M) or no gene (group C) through intracoronary infusion of hemagglutinating virus of Japan (HVJ) liposome. Each group was divided into two subgroups to be subjected to ischemia-reperfusion using Langendorff apparatus with (subgroups M+ and C+) or without (M- and C-) administration of recombinant SOD. RESULTS: Mn-SOD overexpression was confirmed in M with ELISA, activity measurement, and immunohistochemistry. The highest recoveries of maximum and minimum dp/dt and the least creatine phosphokinase (CPK) leakage were observed in M+. These recoveries were higher in M- than in C- and C+. CONCLUSIONS: Thus, endogenous overexpression of Mn-SOD improved myocardial tolerance and its protective effect was enhanced by exogenous administration of SOD. These results suggest a possible strategy for myocardial protection with SOD: a combination of endogenous introduction through gene transfer with exogenous administration.

Animals↗
PubMed1999

Gene transfection of beta 2-adrenergic receptor into the normal rat heart enhances cardiac response to beta-adrenergic agonist.

BACKGROUND: Beta-adrenergic receptor system has a major role in cardiac contraction. If the receptor can be increased by gene transfection by means of intracoronary infusion of beta 2-adrenergic receptor to the hearts in which the receptor is down-regulated, this maneuver may improve the cardiac function and may be applied as one therapeutic approach during cardiopulmonary bypass or percutaneous cardiopulmonary support. METHODS AND RESULTS: The beta 2-adrenergic receptor complementary DNA was transfected in vivo to the normal rat heart by intracoronary infusion by means of a hemagglutinating virus of Japan liposome method, and the transfected heart was transplanted into the abdomen of another rat. Four days after transfection, the sarcolemma of the cardiomyocytes was well labeled by immunohistochemical labeling. Expression of beta-adrenergic receptor in the heart was approximately 4 times greater than that in control hearts (134 +/- 42 vs 33 +/- 4 fmol/mg protein) according to a ligand binding assay. The cardiac response of the transfected heart to isoproterenol was shown to be enhanced in a Langendorff perfusion system: after isoproterenol, developed pressure and maximal derivative of the left ventricle were greater than in the control heart (200 +/- 12 vs 174 +/- 6 mm Hg and 4110 +/- 130 vs 3491 +/- 255 mm Hg/sec), and the minimal derivative of the left ventricle was markedly smaller (-3040 +/- 267 vs -2528 +/- 131 mm Hg/sec). CONCLUSIONS: These results indicate that expression of beta 2-adrenergic receptor was approximately 4 times greater than in normal rat hearts by gene transfection using a hemagglutinating virus of Japan liposome method, and the transfected hearts demonstrated marked enhancements in cardiac response to beta-agonist, suggesting that transfer of this gene by intracoronary infusion has potential as a novel approach to enhance cardiac function.

Adrenergic beta-Agonists↗
PubMed1999

Gene transfer to the rat biliary tract with the HVJ-cationic liposome method.

BACKGROUND/AIMS: The ability to transfer foreign genes into the biliary tract would be useful for the treatment of biliary tract diseases, including cancer, cystic fibrosis and other genetic diseases. To introduce a foreign gene precisely into the rat biliary epithelial cells, we developed a new technique, inserting a polyethylene catheter into the common bile duct through the papilla of Vater by use of a fusigenic cationic liposome with hemagglutinating virus of Japan (HVJ-cationic liposome). METHODS: Transfection efficiency was estimated with the use of FITC-oligonucleotides (FITC-ODNs) and cDNA of beta-galactosidase (pCAG-lacZ). RESULTS: FITC-ODNs encapsulated in HVJ-cationic liposome were effectively transfected into cell nuclei of human cholangiocellular carcinoma in vitro after a 30-min incubation as compared with the simple application of naked FITC-ODNs. After in vivo injection of FITC-ODNs using the HVJ-cationic liposome method through the papilla of Vater, fluorescence accumulation was observed only in the epithelial cells of the biliary tract, but not in the parenchymal cells of the liver. Beta-galactosidase expression was observed in the biliary epithelial cells 3 days after the transfection of pCAG-lacZ and was also detected at 14 days, but not at 28 days, without obvious cytotoxicity. CONCLUSIONS: HVJ-cationic liposome-mediated gene transfer to the biliary tract via the papilla of Vater is a minimally-invasive and an effective gene-delivery method for site-specific targeting to the epithelial cells of the biliary tract, which could be applied to the treatment of human biliary tract diseases.

Animals↗
PubMed1999

Pharmacokinetic differences between rat tumour and lung tissues following isolated lung perfusion with cisplatin.

Isolated lung perfusion has been performed for the treatment of unresectable lung tumours; however, the pharmacokinetics of this procedure remain unclear. This study was conducted to investigate the changes in antitumour drug concentrations in tumour and lung tissues after isolated lung perfusion, using different perfusion times and perfusate drug concentrations. Isolated left lungs were perfused for 20, 40 or 60 min with 25, 50 or 100 micrograms/ml of cisplatin after solitary lung tumour nodules were established in rats, and the total platinum concentrations in the perfused lung and tumour tissues were determined by flameless atomic absorption spectroscopy. The oedema in the perfused lung tissues was evaluated by histological examination and by the wet to dry weight ratios of the lungs. The total platinum concentration increased significantly with perfusion time and increasing perfusate cisplatin concentrations in the lung tissue, but it did not change in the tumour tissue. The wet to dry weight ratios of the lung tissues did not differ significantly among the perfusion groups. Oedema of the perfused lung tissue did not change significantly with the perfusion time or perfusate cisplatin concentration. The results of this study indicate the possibility that different pharmacokinetics exist between tumour and lung tissues following isolated lung perfusion with cisplatin, which could be used as a clinical guide for the selection of appropriate perfusion times and perfusate drug concentrations.

Animals↗
PubMed1999

Gene therapy using HVJ-liposomes: the best of both worlds?

A new concept for the development of novel vectors is to overcome the limitations of individual vectors by combining them. The HVJ-liposome was developed by combining liposomes with fusion proteins derived from the hemagglutinating virus of Japan (HVJ), also known as Sendai virus. Gene transfer in vivo using this delivery system can be repeated because it is much less immunogenic and cytotoxic than other viral-vector systems. By coupling the Epstein-Barr virus (EBV) replicon apparatus with HVJ-liposomes, transgene expression can be sustained in vitro and in vivo. In animal models, this system has shown promise for several diseases, including cancer and cardiovascular disease.

Animals↗
PubMed1999

Optimisation of the biology of soft tissue repair.

As identified in this review, over the past twenty years there have been a number of very exciting new developments in the quest to optimise soft tissue repair. Comparing fetal soft tissue injuries, which heal by regeneration, to the adult processes of healing by inflammation-induced scar formation has led to a number of insights into how the latter may be improved. Seeding wounds with embryonic stem cells, bridging gaps with cell-derived "engineered tissues", addition of exogenous hyaluronic acid and modification of wounds to either enhance the growth factors which have been implicated in regeneration (e.g. TGF-B3) or block those implicated in scar formation (eg. TGF-B1) have all shown promise. Our group has quantified numerous cellular, molecular, biomechanical and matrix abnormalities of scar in a rabbit model of ligament healing. Based on these studies which we review here, three matrix deficiencies have been identified which appear to have specific implications to scar weakness: organisational "flaws", abnormal hydroxypyridinoline collagen cross-link densities and abnormally small, slow-maturing collagen fibrils. In tests aimed at finding therapeutic solutions in this model, the addition of a 7ug bolus of TGF-B1 at day 21 or 2.5ng/day of TGF-B1 being pumped into a wound x 21 days increased the size of ligament scars but did not improve their material strength. It also did not alter any of the above-noted matrix deficiencies. A liposome-mediated anti-sense gene therapy approach aimed at decreasing the expression of the proteoglycan decorin in 21-day scars, however, has significantly increased the size of scar collagen fibrils as well as improved these scars mechanically. Based on these positive results from a single dose of only one targeted molecule, we believe that this gene therapy approach has great potential for further scar improvement. If combined with some of the other biological strategies reviewed above, a repair which is closer to true regenerative healing of ligaments, and all soft tissues, may eventually be achieved.

Animals↗
PubMed1999

Introduction of plasmid DNA and oligonucleotides into lung epithelial cells by the hemagglutinating virus of Japan (HVJ)-liposome method.

The hemagglutinating virus of Japan (HVJ) fused with liposomes provides a unique transfection vehicle with characteristics of both virus vector and liposome. Here we investigate the efficiency and safety of the HVJ-liposome technique in delivering foreign genes and oligonucleotides into the lung of the Wistar rat. A plasmid vector containing the Escherichia coli beta-galactosidase (beta-gal) gene and the chicken beta-actin promoter was transfected via the trachea using the HVJ-liposome method. Cytochemical staining showed expression of exogenous beta-gal activity in airway epithelial cells, alveolar macrophages, and alveolar type II cells. This activity persisted at least 28 days after administration of the genes. FITC-labeled oligonucleotides also were introduced into the same types of lung cells as those expressing beta-gal. After instillation of HVJ-liposome, anti-HVJ antibodies were detected in the sera of the rats, but even after repeated administration of HVJ-liposome, no marked histopathologic change was observed while exogenous beta-gal expression was detected in pulmonary cells.

Actins↗