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Y Kaneda

Publications and source records attributed to Y Kaneda.

At least 73 records · Page 4Linked to original sources
PubMed2001

Digitonin enhances the antitumor effect of cisplatin during isolated lung perfusion.

BACKGROUND: The antitumor effect of isolated lung perfusion with cisplatin was limited because the intracellular platinum concentration did not increase sufficiently. To solve this problem, digitonin, a detergent, was chosen to increase cell permeability and enhance intracellular uptake and antitumor effect. This study was designed to investigate toxicity, pharmacokinetics, and efficacy of isolated lung perfusion with the combined use of digitonin and cisplatin in Fischer 344 rats. METHODS: Systemic and local toxicities of isolated lung perfusion treatment were evaluated on the basis of body weight change, survival rate, and histologic findings. The maximal tolerated dose of digitonin was determined by assessing survival on day 21 after contralateral pneumonectomy, body weight change, and histologic findings. Pharmacokinetics were observed in a solitary lung tumor nodule model by measuring platinum concentration in tumor and normal lung tissue. The antitumor effect was evaluated by the number of tumor nodules in the left lung 21 days after isolated lung perfusion. Isolated lung perfusion was performed 7 days after 1.0 x 10(6) methylcholanthrene sarcoma cells were injected into the external jugular vein. RESULTS: The maximal tolerated dose of digitonin was 20 micromol/L. Platinum concentration of tumor nodules in the digitonin-cisplatin-treated rats was 20% higher than in the cisplatin-only group (5.48 +/- 0.64 microg/g tissue versus 4.50 +/- 1.09 microg/g tissue; p = 0.067). The number of pulmonary nodules decreased significantly by digitonin use (1.3 +/- 1.5 versus 9.7 +/- 2; p < 0.0001). CONCLUSIONS: Isolated lung perfusion with digitonin and cisplatin in combination was performed safely and enhanced the antitumor effect. These drugs in combination show promise for enhancing the effect of clinical isolated lung perfusion.

Animals↗
PubMed2001

Gene therapy in vascular medicine: recent advances and future perspectives.

Gene therapy is emerging as a potential strategy for the treatment of cardiovascular diseases, such as restenosis after angioplasty, vascular bypass graft occlusion, and transplant coronary vasculopathy, for which no known effective therapy exists. The first human trial in cardiovascular disease was started in 1994 to treat peripheral vascular disease using vascular endothelial growth factor. In addition, therapeutic angiogenesis using the vascular endothelial growth factor gene was applied in the treatment of ischemic heart disease. The results from these clinical trials seem to exceed expectation. Improvement of clinical symptoms in peripheral arterial disease and ischemic heart disease has been reported. At least five different potent angiogenic growth factors have been tested in clinical trials to treat peripheral arterial disease or ischemic heart disease. In addition, another strategy for combating disease processes, to target the transcriptional process, has been tested in a human trial. Transfection of cis-element double-stranded oligodeoxynucleotides is an especially powerful tool in a new class of antigen strategies for gene therapy. Transfection of double-stranded oligodeoxynucleotides corresponding to the cis sequence will result in the attenuation of the authentic cis-trans interaction, leading to the removal of trans-factors from the endogenous cis-elements, with subsequent modulation of gene expression. Genetically modified vein grafts transfected with a decoy against E2F, an essential transcription factor in cell cycle progression, revealed apparent long-term potency in human patients. This review focuses on the future potential of gene therapy for the treatment of cardiovascular disease.

Angioplasty↗
PubMed2001

Platelet serotonin concentrations in medicated schizophrenic patients.

1. The present study was conducted to investigate the effects of neuroleptic administration on platelet serotonin (5-HT) levels, and the relationships between platelet 5-HT levels, extrapyramidal symptoms (EPS) and psychopathology in schizophrenia. 2. The subjects were 49 regularly medicated inpatients who were diagnosed according to the DSM-IV criteria for schizophrenia. Each patient gave informed consent for the research involved in this study. All patients were first considered as one group and then divided into two groups: those with lower levels (LL) and those with higher levels (HL), according to their platelet 5-HT levels. Psychotic symptoms and EPS were assessed using the Brief Psychiatric Rating Scale and the Drug Induced Extra-Pyramidal Symptoms Scale, respectively. 3. (1) The mean level of the platelet 5-HT in the schizophrenics with neuroleptic-treatment was significantly lower than that in the normal subjects. (2) The mean level of the blood monoamine oxidase (MAO) in the schizophrenics tended to be lower than that in the normal subjects. (3) There was no significant difference in the mean scores of the positive symptoms, negative symptoms, or EPS between the LL and HL groups. (4) Platelet 5-HT levels were not correlated with blood MAO concentrations. 4. Overall, these results seem to indicate that (i) administration of neuroleptics lowers platelet 5-HT levels, and (ii) platelet 5-HT levels in the schizophrenics with neuroleptic-treatment do not reflect psychopathology of schizophrenia or severity of neuroleptic-induced EPS.

Adult↗
PubMed2001

The influence of tumour resection on angiostatin levels and tumour growth--an experimental study in tumour-bearing mice.

The phenomenon of primary neoplasms inhibiting the growth of their metastatic lesions is thought to be related to endogenous angiogenesis inhibitors. The aim of this experiment was to investigate the influence of tumour resection on angiostatin levels and tumour growth using a tumour-bearing mouse model. A primary Lewis lung cancer tumour model was established in C57BL/6 mice and these mice were divided into two groups 10 days after the tumour cells were inoculated. In the surgical resection group (S group) the tumour was resected, but in the control group (C group) a sham operation was performed. The level of angiostatin in the sera was analysed 5 days after the operation by western blotting. To observe tumour growth, four Lewis lung cancer models were established in these mice from both the S and C groups. An immunohistochemical analysis of the tumour tissues was conducted to estimate the proliferation and apoptotic rates of the tumour cells, as well as the amount of neoangiogenesis in the tumours. Angiostatin was observed in the tumour-bearing mice, but disappeared within 5 days after the tumour had been resected. Increased tumour growth was observed in all of the tumour models in the S group compared with the C group and the differences were significant. A significantly higher intratumour vessel density and proliferation cell index, but a significantly lower apoptotic index were also found in the S group compared with the C group. These findings demonstrated that angiostatin was generated directly from the tumour tissue. Furthermore, tumour resection accelerates the growth of other tumours and this is probably related to multiple factors including increased neoangiogenesis, increased tumour cell proliferation, and decreased apoptosis.

Angiostatins↗
PubMed2001

Preclinical and therapeutic utility of HVJ liposomes as a gene transfer vector for hepatocellular carcinoma using herpes simplex virus thymidine kinase.

Although gene therapy has been suggested to be a novel strategy to treat hepatocellular carcinoma (HCC), no study showing the clinical feasibility of vectors to treat HCC has been reported. In this preclinical study, we show evidence indicating that hemagglutinating virus of Japan (HVJ) liposomes are a feasible vector to treat HCC in a clinical setting using ganciclovir (GCV) and herpes simplex virus thymidine kinase (HSV-tk), which is driven by the cytomegalovirus immediate early enhancer/promoter (plasmid pcDNA3/HSV-tk). In in vitro experiments, almost complete tumor cell regression was achieved with the optimal GCV concentration (100 microg/mL) and more than 1/3 regression was seen even with a 20% transduction ratio using HuH7 HCC cells stably transformed by HSV-tk. HVJ liposomes showed a 19.7% (mean) transduction rate of the lacZ gene in a relatively large mass of more than 300 mm3 in vivo, which is a clinically detectable size, implanted into SCID mice. Moreover, a single HSV-tk injection of HVJ liposomes followed by GCV treatment inhibited tumor growth at least within a week, and repeat administration was more effective. Furthermore, subcutaneous injection of an HVJ liposomes vehicle induced no apparent inflammatory response in C3H/HeN mice, whereas lacZ gene transfection resulted in inflammatory pathology, suggesting a lower immunogenicity of the HVJ envelope protein than those of bacteria-derived plasmid DNA or the beta-galactosidase gene product. From these findings, we conclude that HVJ liposomes are a clinically safe and effective gene transfer vector to treat HCC.

Animals↗
PubMed2001

Novel immunotherapy for peritoneal dissemination of murine colon cancer with macrophage inflammatory protein-1beta mediated by a tumor-specific vector, HVJ cationic liposomes.

A critical issue for cancer treatment is control of metastatic or disseminated tumors. Although immune gene therapy has been considered as a possible strategy for treatment of such tumors, successful results have not yet been obtained. To evoke antitumor immunity more efficiently, macrophage inflammatory protein-1beta (MIP-1beta) was used for gene therapy of colon cancer in mice. Injection of hemagglutinating virus of Japan (HVJ) cationic liposomes-MIP-1beta into subcutaneous tumor masses resulted in local expression of MIP-1beta and local accumulation of CD4(+) T lymphocytes. Few studies of cancer gene therapies have targeted peritoneal dissemination. In a mouse model of peritoneal dissemination of colon tumor, we used a luciferase-based assay to demonstrate that HVJ cationic liposomes had high tumor specificity and were effective vectors for transfer of genes in peritoneal dissemination. When mice were treated by intraperitoneal injection of HVJ cationic liposomes containing the MIP-1beta gene, the survival periods of the MIP-1beta-treated mice were significantly longer than those of control mice. Therefore, this HVJ cationic liposome strategy may serve as a powerful tool against peritoneal disseminated cancer.

Animals↗
PubMed2001

HVJ-liposome-mediated transfection of HSVtk gene driven by AFP promoter inhibits hepatic tumor growth of hepatocellular carcinoma in SCID mice.

Suicide gene therapy using ganciclovir (GCV) with transfection of the herpes thymidine kinase (HSVtk) gene has been studied for cancer therapy. The present study demonstrates an efficient method of suicide gene therapy for multiple hepatic tumors, involving repetitive transfection of the HSVtk gene driven by the alpha-fetoprotein (AFP) promoter using hemagglutinating virus of Japan (HVJ)-liposomes. AFP-producing cells (HUH7) and AFP-nonproducing cells (LS180) were injected subcutaneously (s.c.) to establish tumors in nude mice. Two plasmid constructs, bacterial LacZ gene driven by the AFP promoter (AFPLacZ), and HSVtk gene driven by the AFP promoter (AFPTK1) were encapsulated into the HVJ-liposome and used. When AFPLacZ was injected into the s.c. tumors, expression of LacZ gene was confined to HUH7 tumors. Repeated transfection of AFPTK1 followed by GCV treatment markedly suppressed growth of HUH7 tumors, and apoptosis of HUH7 cells was recognized in the tumor. Next, HUH7 cells were injected into the portal vein in severe combined immunodeficiency mice to establish a hepatic tumor model. After inoculation with the tumor, HVJ-liposomes containing the AFPTK1 plasmid vector were injected into the portal vein via the splenic hilum, followed by GCV treatment. This gene therapy significantly inhibited the growth of tumors in the liver and markedly improved survival. Three injections of the AFPTK1 plasmid vector completely inhibited tumor growth. This procedure seems to have great potential for the treatment of multiple hepatic tumors.

Animals↗
PubMed2001

Therapeutic angiogenesis induced by human hepatocyte growth factor gene in rat and rabbit hindlimb ischemia models: preclinical study for treatment of peripheral arterial disease.

Hepatocyte growth factor (HGF) exclusively stimulates the growth of endothelial cells without replication of vascular smooth muscle cells, and acts as a survival factor against endothelial cell death. Recently, a novel therapeutic strategy for ischemic diseases using angiogenic growth factors to expedite and/or augment collateral artery development has been proposed. We have previously reported that intra-arterial administration of recombinant HGF induced angiogenesis in a rabbit hindlimb ischemia model. In this study, we examined the feasibility of gene therapy using HGF to treat peripheral arterial disease rather than recombinant therapy, due to its disadvantages. Initially, we examined the transfection of 'naked' human HGF plasmid into a rat hindlimb ischemia model. Intramuscular injection of human HGF plasmid resulted in a significant increase in blood flow as assessed by laser Doppler imaging, accompanied by the detection of human HGF protein. A significant increase in capillary density was found in rats transfected with human HGF as compared with control vector, in a dose-dependent manner (P < 0.01). Importantly, at 5 weeks after transfection, the degree of angiogenesis induced by transfection of HGF plasmid was significantly greater than that caused by a single injection of recombinant HGF. As an approach to human gene therapy, we also employed a rabbit hindlimb ischemia model as a preclinical study. Naked HGF plasmid was intramuscularly injected in the ischemic hindlimb of rabbits, to evaluate its angiogenic activity. Intramuscular injection of HGF plasmid once on day 10 after surgery produced significant augmentation of collateral vessel development on day 30 in the ischemia model, as assessed by angiography (P < 0.01). Serial angiograms revealed progressive linear extension of collateral arteries from the origin stem artery to the distal point of the reconstituted parent vessel in HGF-transfected animals. In addition, a significant increase in blood flow was assessed by a Doppler flow wire and the ratio in blood pressure of the ischemic limb to the normal limb was observed in rabbits transfected with HGF plasmid as compared with rabbits transfected with control vector (P < 0.01). Overall, intramuscular injection of naked human HGF plasmid induced therapeutic angiogenesis in rat and rabbit ischemic hindlimb models, as potential therapy for peripheral arterial disease.

Animals↗
PubMed2001

Intravenous injection of oligodeoxynucleotides to the NF-kappaB binding site inhibits hepatic metastasis of M5076 reticulosarcoma in mice.

We have developed synthetic double-stranded oligodeoxynucleotides (ODN) as 'decoy' cis elements that block the binding of nuclear factors to promoter regions of targeted genes, resulting in the inhibition of gene transactivation in vivo. In the present study, we employed decoy ODN targeting the transcription factor nuclear factor-kappaB (NF-kappaB) binding cis-elements to hepatic metastasis of murine reticulosarcoma M5076 in mice. Intravenous inoculation of M5076 into mice caused a marked increase in gene expression of interleukin-1beta, tumor necrosis factor-alpha and intercellular adhesion molecule-1 in the liver, whereas intravenous treatment with NF-kappaB decoy ODN reduced M5076-induced transactivation of these genes. Treatment with NF-kappaB decoy ODN, but not scrambled decoy ODN, significantly inhibited hepatic metastasis of M5076 in mice, and furthermore the combined treatment of NF-kappaB decoy ODN with an anti-cancer drug resulted in complete inhibition of hepatic metastasis in half of the mice, without affecting myelosuppression induced by the anti-cancer drug. Here, NF-kappaB decoy ODN inhibited hepatic metastasis of M5076 in mice possibly through a decrease in transactivation of important NF-kappaB-driven genes and also potentiated the anti-metastatic effect of an anti-cancer drug, demonstrating the first successful in vivo therapy for cancer metastasis using NF-kappaB decoy ODN as a novel molecular decoy approach.

Animals↗
PubMed2001

Gene therapy for preventing neuronal death using hepatocyte growth factor: in vivo gene transfer of HGF to subarachnoid space prevents delayed neuronal death in gerbil hippocampal CA1 neurons.

To develop a novel strategy to prevent delayed neuronal death (DND) following transient occlusion of arteries, the gene of hepatocyte growth factor (HGF), a novel neurotrophic factor, was transfected into the subarachnoid space of gerbils after transient forebrain ischemia. Importantly, transfection of HGF gene into the subarachnoid space prevented DND, accompanied by a significant increase in HGF in the cerebrospinal fluid. Prevention of DND by HGF is due to the inhibition of apoptosis through the blockade of bax translocation from the cytoplasm to the nucleus. HGF gene transfer into the subarachnoid space may provide a new therapeutic strategy for cerebrovascular disease.

Animals↗
PubMed2001

Inhibition of intimal hyperplasia after balloon injury in rat carotid artery model using cis-element 'decoy' of nuclear factor-kappaB binding site as a novel molecular strategy.

The transcription factor, NFkB, plays a pivotal role in the coordinated transactivation of cytokine and adhesion molecule genes involved in atherosclerosis and lesion formation after vascular injury. We hypothesized that synthetic double-stranded DNA with high affinity for NFkB may be introduced as a 'decoy' cis element to bind the transcription factor, and block gene activation, resulting in an effective therapeutic agent for treating intimal hyperplasia. In vivo transfection of NFkB decoy oligodeoxynucleotides (ODN) into balloon-injured rat carotid artery resulted in the inhibition of neointimal formation at 14 days after injury as compared with vessels transfected with scrambled ODN (P < 0.01). It is of importance to note that in the vessels transfected with NFkB decoy ODN, the expression of p53, a pro-apoptotic gene, was upregulated in neointimal area, followed by increased apoptosis at 14 days. In addition, gene expression of ICAM-1 and VCAM-1 was markedly decreased in blood vessels transfected with NFkB decoy ODN compared with scrambled ODN, whereas balloon injury induced ICAM and VCAM expression in the neointimal area. More importantly, the migration of macrophages and T-lymphocytes into the neointima and media was significantly inhibited by NFkB decoy ODN as compared with scrambled ODN. Here, we demonstrated that in vivo transfer of NFkB decoy ODN successfully inhibited neointimal formation after balloon injury, accompanied by (1) induction of apoptosis through p53 upregulation, and (2) inhibition of local inflammatory actions through the downregulation of adhesion molecules. These results suggest that decoy treatment against NFkB provides a new therapeutic strategy to inhibit neointimal hyperplasia after angioplasty.

Animals↗
PubMed2001

Dominant negative c-jun gene transfer inhibits vascular smooth muscle cell proliferation and neointimal hyperplasia in rats.

We previously reported that activator protein-1 (AP-1), containing c-Jun, is rapidly activated in balloon-injured artery. Therefore, we examined the role of c-Jun in vascular smooth muscle cell (SMC) proliferation, by using in vitro and in vivo gene transfer techniques. (1) Serum (2%) stimulation significantly increased AP-1 DNA binding activity in aortic SMCs, followed by the increase in both 3H-thymidine incorporation and cell number. Aortic SMCs were infected with recombinant adenovirus containing TAM67, a dominant negative c-Jun lacking transactivation domain of wild c-Jun (Ad-DN-c-Jun), to specifically inhibit AP-1. Ad-DN-c-Jun significantly inhibited serum-induced SMC proliferation, by inhibiting the entrance of SMC into S phase. (2) The effect of DN-c-Jun was examined on balloon injury-induced intimal hyperplasia in rats. Before balloon injury, DN-c-Jun was transfected into rat carotid artery using the hemagglutinating virus of Japan-liposome method. In vivo transfection of DN-c-Jun significantly inhibited vascular SMC proliferation in the intima and the media and subsequently prevented intimal thickening at 14 days after balloon injury. We obtained the first evidence that DN-c-Jun gene transfer prevented vascular SMC proliferation in vitro and in vivo, and c-Jun was involved in balloon injury-induced intimal hyperplasia. Thus, AP-1 seems to be the new therapeutic target for treatment of vascular diseases.

Animals↗
PubMed2001

Prolonged transgene expression in glomeruli using an EBV replicon vector system combined with HVJ liposomes.

BACKGROUND: Various gene transfer vectors as well as delivery systems have been developed; however, many problems remain to be solved. We already achieved a technique to introduce genes into glomerular mesangial cells by hemagglutinating virus of Japan (HVJ) liposome-mediated gene transfer via renal artery. The main limitation of this method is the transient transgene expression. METHOD: For long-term gene expression in glomeruli, Epstein-Barr virus (EBV) replicon-based plasmid was employed, containing the latent viral DNA replication origin (oriP) and EBV nuclear antigen-1 (EBNA-1), which are the minimum EBV component of transgene-nuclear retention. To examine the effect of EBV replicon apparatus on the duration of transgene expression in glomeruli in vivo, the EBV replicon vector pEBActLuc, and the control plasmid vector pActLuc were adopted. These plasmid vectors were transferred into the kidney via renal artery by using artificial viral envelope (AVE)-type HVJ liposome method, and glomerular luciferase activities were analyzed at various time points after transfection. RESULTS: On day 4, pEBActLuc and pActLuc transfer resulted in equal glomerular luciferase activity, and the luciferase gene expression was sustained for at least 56 days in glomeruli transfected with pEBActLuc, whereas it was reduced on seven days in glomeruli transfected with pActLuc. CONCLUSION: The combination of EBV replicon apparatus and HVJ liposomes appears to be a powerful tool for long-term gene expression in vivo, and furthermore, it may be a promising new therapeutic method for the progression of renal disease.

Animals↗
PubMed2001

Nuclear factor-kappa B decoy attenuates neuronal damage after global brain ischemia: a future strategy for brain protection during circulatory arrest.

OBJECTIVES: Recent studies have reported that cis element decoy oligodeoxynucleotides against nuclear factor-kappa B block the activation of genes that mediate ischemic injury. To improve brain protection during circulatory arrest in cardiac surgery, we evaluated the efficacy of nuclear factor-kappa B decoy oligodeoxynucleotides in preventing neuronal damage after global brain ischemia. METHODS: Hemagglutinating virus of Japan-liposome complex with fluorescein isothiocyanate-labeled nuclear factor-kappa B decoy oligodeoxynucleotides was injected through the carotid artery during 20 minutes of global brain ischemia in rats to evaluate the efficacy of transfecting the decoy oligodeoxynucleotides. The messenger RNA levels of several factors related to ischemia-reperfusion injury in the hippocampus were estimated by a real-time polymerase chain reaction method 1 hour after reperfusion. Neuronal damage was evaluated by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling staining and by using immunohistochemical study of microtubule-associated protein 2 in the hippocampus CA-1 region 7 days after ischemia. RESULTS: Introduction of the nuclear factor-kappa B decoy oligodeoxynucleotides into rat brain neurons through the carotid artery during global brain ischemia was markedly successful. The polymerase chain reaction study showed that the transfected nuclear factor-kappa B decoy oligodeoxynucleotides effectively inhibited the expression of tumor necrosis factor alpha interleukin 1 beta and intracellular adhesion molecule 1 messenger RNA 1 hour after global brain ischemia. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling staining and microtubule-associated protein 2 immunohistochemistry showed that the transfected nuclear factor-kappa B decoy oligodeoxynucleotides significantly attenuated the neuronal damage 7 days after global brain ischemia. CONCLUSIONS: Therapeutic transfection of nuclear factor-kappa B decoy oligodeoxynucleotides during brain ischemia may be useful for attenuating neuronal damage, suggesting a strategy for cerebral protection against global ischemia.

Animals↗
PubMed2001

Improvements in gene therapy technologies.

We have combined hemagglutinating virus of Japan (HVJ; Sendai virus) with liposomes for efficient in vitro and in vivo fusion-mediated gene delivery. The HVJ-liposome was a highly efficient vehicle for the introduction of oligonucleotides into cells in vivo as well as for the transfer of genes <100 kbp without damaging cells. By coupling the Epstein-Barr (EB) virus replicon apparatus with HVJ-liposomes (virosomes), transgene expression was sustained in vitro and in vivo. When we added cationic lipids, the HVJ-cationic liposomes increased gene delivery 100 to 800 times in vitro compared with the conventional anionic virosomes and were also more useful for gene expression in restricted areas of organs and for gene therapy of disseminated cancers. We further discovered that the use of anionic virosomes with a virus-mimicking lipid composition (artificial viral envelope; AVE type) increased transfection efficiency approximately 10 fold in vivo, especially in the heart, liver, kidney, and muscle. Most animal organs were found to be suitable targets for the fusigenic virosomes, and numerous gene therapy strategies using this system were successful in animals. The combination of suicide gene therapy with radiation was very effective for killing hepatomas in a mouse model. Arteriosclerosis obliterans in animal models was cured by the transfer of hepatocyte growth factor.

Animals↗