Publications by authors named "Yoshito Eizuru"

Previous studies have reported the detection of a truncated E1 mRNA generated from HPV-18 in HeLa cells. Although it is unclear whether a truncated E1 protein could function as a replicative helicase for viral replication, it would still retain binding sites for potential interactions with different host cell proteins. Furthermore, in this study, we found evidence in support of expression of full-length HPV-18 E1 mRNA in HeLa cells.

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Prostacyclin synthase (PGIS or PTGIS) is an enzyme that catalyses the conversion of prostaglandin H2 (PGH2) to prostaglandin I2 (PGI2). PGI2 promotes cancer growth by activating peroxisome proliferator-activated receptor δ (PPARδ), and increases the expression levels of the pro-angiogenic factor vascular endothelial growth factor (VEGF). We found that the expression of the PGIS gene was enhanced in WI-38, TIG-3-20 and HEL human lung fibroblast cells and two cancer cell lines (NB-1 and G361) under hypoxic conditions.

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Human phospholipid scramblase 1 (PLSCR1) is an interferon (IFN)-stimulated gene and possesses an IFN-mediated antiviral function. We show here that PLSCR1 directly interacts with human immunodeficiency virus type-1 (HIV-1) Tat. This interaction occurs both in vitro and in vivo through amino acids 160-250 of PLSCR1.

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Human phospholipid scramblase (PLSCR) 1 expression is strongly activated in response to interferon (IFN) treatment and viral infection, and PLSCR1 is necessary for the IFN-dependent induction of gene expression and antiviral activity. We show here that PLSCR1 directly interacts with human T-cell leukemia virus type-1 (HTLV-1) Tax in vitro and in vivo. This interaction reduced the cytoplasmic distribution of Tax.

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Antigen retrieval (AR) and ultra-super sensitive immunohistochemistry (ultra-IHC) have been established for application to archival human pathology specimens. The original ultra-IHC was the ImmunoMax method or the catalyzed signal amplification system (ImmunoMax/CSA method), comprising the streptavidin-biotin complex (sABC) method and catalyzed reporter deposition (CARD) reaction with visualization of its deposition. By introducing procedures to diminish non-specific staining in the original ultra-IHC method, we developed the modified ImmunoMax/CSA method with AR heating sections in an AR solution (heating-AR).

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The smoking habit is the most important, but not a sufficient cause for lung cancer development. Several studies have reported the human papillomavirus type 16 (HPV16) presence and E6 and E7 transcripts expression in lung carcinoma cases from different geographical regions. The possible interaction between HPV infection and smoke carcinogens, however, remains unclear.

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Aim: To clarify human papillomavirus (HPV) involvement in carcinogenesis of the upper digestive tract of virological and pathological analyses.

Methods: The present study examined the presence of HPV in squamous cell carcinomas of the oral cavity (n = 71), and esophagus (n = 166) collected from Japan, Pakistan and Colombia, with different HPV exposure risk and genetic backgrounds. The viral load and physical status of HPV16 and HPV16-E6 variants were examined.

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Immunohistochemistry (IHC) for detecting key signal molecules involved in programmed cell death (PCD) in archival human pathology specimens is fairly well established. Detection of cleaved caspase-3 in lymphocytes in rheumatoid arthritis (RA) and gastric surface foveolar glandular epithelia but not in synoviocytes in RA, gastric fundic glandular epithelia, or nasal NK/T-cell lymphoma (NKTCL) cells suggests anti-apoptotic mechanisms in cell differentiation and in oncogenesis such as the induction of survivin. Enzymatically pretreated and ultra-super sensitive detection of beclin-1 in synoviocytes in RA and gastric fundic glandular epithelia suggests enhanced autophagy.

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Aim: To clarify the reason for the low frequency of Epstein-Barr virus-associated gastric carcinoma (EBVaGC) in Peru, despite the high frequency reported in neighboring countries, the distribution of the distinctive EBV (type i/XhoI+) strain in EBVaGC and a healthy population was examined.

Materials And Methods: EBV polymorphisms in BamHI W1/I1 and XhoI restriction site of the latent membrane protein 1 gene (LMP1) were examined among 11 EBVaGCs and 172 healthy controls from Peru, and these frequencies were compared with those in a previous study of Chile and Colombia (n=303).

Results: The frequency of the distinctive EBV strain in EBVaGCs (55%) was significantly higher than that in controls (7%).

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This study investigated autophagy in 37 cases of nasopharyngeal lymphomas including 23 nasal natural killer (NK)/T-cell lymphomas (NKTCL), 3 cytotoxic T-cell lymphomas (cytotoxic-TML) and 9 B-cell lymphomas (BML) by means of antigen-retrieval immunohistochemistry of beclin-1, LC3, mitochondria (AE-1) and cathepsin D. Peculiar necrosis was noted in EBV(+) lymphomas comprising 21 NKTCL, 2 cytotoxic-TML and 1 BML. Lymphomas without peculiar necrosis showed high expression of beclin-1, macrogranular cytoplasmal stain of LC3 with sporadic nuclear stain, a hallmark of autophagic cell death (ACD), some aggregated mitochondria and high expression of cathepsin D, suggesting a state of growth with enhanced autophagy with sporadic ACD.

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Background: Human papillomavirus (HPV) and Epstein Barr virus (EBV) have been found in breast carcinomas (BCs) around the world. In this study, fifty-five BCs from Chile were analyzed for HPV and EBV presence. In addition, HPV-16 viral load/physical status and E6/E7 expressions were determined.

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The I-mfa domain proteins I-mfa and HIC are considered to be candidate tumor suppressor genes and have been shown to be involved in transcriptional regulation. We show here that I-mfa and HIC specifically interact with SEI-1 through their C-terminal I-mfa domains in vivo. This interaction affects the intracellular localization of I-mfa and requires the region of SEI-1 between 30 and 90 amino acids, which includes its SERTA domain, and results in repression of its intrinsic transcriptional activity.

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Background: Although human papillomavirus (HPV) genome has been detected in lung cancer, its prevalence is highly variable around the world. Higher frequencies have been reported in far-east Asian countries, when compared with European countries. The present study analysed the HPV-16 presence in 60 lung carcinomas from the Asian countries China, Pakistan and Papua New Guinea.

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Unlabelled: The aim of the present study was to elucidate the etiological roles of Epstein-Barr virus (EBV) in the development of EBV-associated GC (EBV-GC), EBV-GCs and non EBV-GCs were compared with regard to the expression of thymidine phosphorylase (TP), which is known to have angiogenic activity in various tumor tissues.

Patients And Methods: TP expression was examined by immunohistochemistry assay among 156 gastric carcinoma cases (21 EBV-GC cases and 135 non EBV-GC cases).

Results: The frequency of tumors with TP expression was nearly twice as high in EBV-GCs (71%) than in non EBV-GCs (37%) (p=0.

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Kaposi's sarcoma-associated herpes virus (KSHV)-encoded latency-associated nuclear antigen (LANA) protein has been reported to interact with glycogen synthase kinase 3beta (GSK-3beta) and to negatively regulate its activity, leading to stimulation of GSK-3beta-dependent beta-catenin degradation. We show here that the I-mfa domain proteins, HIC (human I-mfa domain-containing protein) and I-mfa (inhibitor of MyoD family a), interacted in vivo with LANA through their C-terminal I-mfa domains. This interaction affected the intracellular localization of HIC, inhibited the LANA-dependent transactivation of a beta-catenin-regulated reporter construct, and decreased the level of the LANA.

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A number of studies have reported the presence of human papillomavirus (HPV) in lung carcinoma. Interestingly, its detection rate appears to differ histologically and geographically. The present study examined 30 adenocarcinomas and 27 squamous cell carcinomas of the lung in a southern area of Japan, and detected high-risk HPV genome in 9 (30%) adenocarcinomas and 2 (7%) squamous cell carcinomas, using PCR with SPF10 primers and INNO-LiPA HPV genotyping assay.

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Cytomegalovirus (CMV) infection is a prominent infection in transplant recipients. The immunosuppressive drug mizoribine was shown to have anti-CMV activity in vitro and was reported to have an anti-CMV effect in renal transplantation. This study characterized the anti-CMV activity of mizoribine in vitro and its synergistic activity with ganciclovir.

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Introduction: Although the integration of human T-cell lymphotropic virus type I into the T-cells is not a random process, the mechanistic details are not understood.

Objectives: The characteristics of the flanking host chromatin were evaluated at the integration sites in adult T-cell leukaemia/lymphoma (ATLL) patients infected with the virus.

Materials And Methods: From seven leukemic Colombian patients positive for the human T-cell lymphotropic virus type I (HTLV-I), lymphocyte DNA samples were extracted and amplified by inverse polymerase chain reaction (IPCR).

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Human cytomegalovirus (HCMV) is a herpesvirus associated with serious diseases in immunocompromised subjects. The region between ORF UL133 and UL151 from HCMV, named ULb' is frequently deleted in attenuated AD169 and in highly passaged laboratory strains. However, this region is conserved in low-passaged and more virulent HCMV, like the Toledo strain.

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This study examined the relationship between external environmental factors and Epstein-Barr virus (EBV) infection in nasal natural killer (NK)/T-cell lymphomagenesis. Archival paraffin sections from 134 cases of nasopharyngeal lymphomas in the northeast of China were investigated by in situ hybridization of EBV-encoded small RNA-1 (EBER-1) and by immunohistochemistry of the status of programmed cell death (PCD). The cases examined included 74 (55.

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The inactivation of tumour suppressor genes by aberrant methylation of promoter regions has been described as a frequent event in neoplasia development, including lung cancer. The p16 gene is a tumour suppressor gene involved in the regulation of cell cycle progression that has been reported to be inactivated by promoter methylation in lung carcinomas at variable frequencies around the world in a smoking habit dependent manner. The purpose of this study was to investigate the methylation status of the promoter region of the p16 gene in 74 non-small cell lung carcinomas from Chile.

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In this paper, the roles of Epstein-Barr virus (EBV) in gastric carcinogenesis are discussed, reviewing mainly epidemiological and clinicopathological studies. About 10% of gastric carcinomas harbor clonal EBV. LMP1, an important EBV oncoprotein, is only rarely expressed in EBV-associated gastric carcinoma (EBV-GC) while EBV-encoded small RNA is expressed in almost every EBV-GC cell, suggesting its importance for developing and maintaining this carcinoma.

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Aim: To examine the role of E-cadherin and beta-catenin in carcinogenesis and to assess their prognostic implication in Epstein-Barr virus-associated gastric carcinomas (EBV-GCs).

Methods: We compared the frequency of E-cadherin and beta-catenin expression in 59 EBV-GCs and 120 non-EBV-GCs, and examined the association between patients' prognosis and the expressions of these proteins.

Results: Neither the cellular-membranous nor the cytoplasmic E-cadherin expression showed any difference between EBV-GCs and non-EBV-GCs.

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We examined the anticytomegalovirus properties of four compounds: pristimerin, the pristimerin analogue, lupeol and 2-acetylphenol-1-beta-D-glucopyranosyl (1 --> 6)-beta-D-xylpyranoside (acetophenol glycoside), isolated from Maytenus heterophylla, a Kenyan medicinal plant. The effects were studied on human cytomegalovirus (HCMV) replication in the human embryonic fibroblast cell line, MRC-5. In a viral plaque-reduction assay, pristimerin showed dose-dependent inhibitory properties with a 50% inhibitory concentration of 0.

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Primary lymphoepitheliomalike carcinomas (LELC) of the esophagus are uncommon, with only 29 previously reported cases in the literature. Primary LELC of the esophagus is associated with Epstein-Barr virus (EBV). We herein report a 52-year-old man who presented with dysphagia and weight loss and was found to have a polypoid mass in the middle esophagus.

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