Sadayuki Hiroi

National Defense Medical College, Tokorozawa, Saitama, Japan

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Publications (49)207.48 Total impact

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    ABSTRACT: Matrix-assisted laser desorption/ionisation spiral orbit-type time-of-flight mass spectrometry (MALDI-SpiralTOF) can analyse lipid profiles and characterise lipid structure. Imaging mass spectrometry (IMS) also provides distribution maps of selected m/z values. Here, we investigated triacylglycerol (TG) structure and distribution using these technologies to estimate mouse fatty liver. The distribution and intensity of the most intense mass spectrum ion was indicated by IMS at m/z 881.7 (52:2). Analysis using MS/MS showed a structural change between liver TG and dietary TG. These findings suggest that MALDI-SpiralTOF is a powerful tool for clinical screening and estimating fatty liver.
    FEBS Open Bio. 01/2014;
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    ABSTRACT: Parkinson's disease is associated with DJ-1/Parkinson protein 7 dysfunction. In contrast, hyperactivity of DJ-1 increases the resistance of cancer cells to apoptosis. Recent genetic studies showed that, in addition to apoptosis pathways, DJ-1 is also involved in cellular defense against reactive oxygen species. The activity of apoptotic and cellular defense pathways is key in determining drug sensitivity. DJ-1 overexpression is associated with various cancers. However, we previously found that there were approximately 50 % patients with breast cancers that expressed low levels of DJ-1 protein, despite mRNA upregulation. Furthermore, low DJ-1 expression was a significant predictor of poor clinical outcome in these patients. This study aimed to determine the association between low DJ-1 protein expression and pathological complete remission (pCR) after neoadjuvant chemotherapy in breast cancer patients. Expression of DJ-1 in pre-therapeutic needle biopsies and surgical specimens obtained from 205 breast cancer cases that received neoadjuvant chemotherapy was determined using immunohistochemistry and in situ hybridization. Chemotherapy comprised epirubicin/cyclophosphamide taxane-based regimens with or without the inclusion of trastuzumab. Univariate and multivariate analyses were used to evaluate the predictive value of DJ-1 on pCR. Low DJ-1 protein expression was detected in 45.3 % (93/205) of all breast cancer cases and in 79.6 % (39/49) of pCR cases, irrespective of maintained mRNA levels. DJ-1 expression [hazard ratio (HR): 1.36; 95 % confidence interval (CI): 1.01-1.84] and HER2 status (HR: 0.84; 95 % CI: 0.62-1.14), in contrast to histological grade, hormone receptors status, Ki-67 labeling index, and intrinsic subtype, were significant predictors of pCR. Low DJ-1 expression predicted pCR in luminal A (P = 0.0004), luminal B (P = 0.0194), and triple negative (P = 0.0143) subtypes breast cancer patients and in patients receiving additional trastuzumab treatment (P = 0.008). In conclusion, low DJ-1 protein expression is a significant predictor of pCR after neoadjuvant chemotherapy in breast cancer patients.
    Breast Cancer Research and Treatment 04/2013; · 4.47 Impact Factor
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    ABSTRACT: Experimental pulmonary hypertension that develops in hypobaric hypoxia is characterized by structural remodeling of the lung. Proteomics - which may be the most powerful way to uncover unknown remodeling proteins involved in enhancing cardiovascular performance - was used to study 150 male Wistar rats housed for up to 21 days in a chamber at the equivalent of 5500m altitude level. After 14 days' exposure to hypobaric hypoxia, pulmonary arterial pressure (PAP) was significantly increased. In lung tissue, about 140 matching protein spots were found among 8 groups (divided according to their hypobaric period) by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) (pH4.5-pH6.5, 30kDa-100kDa). In hypobaric rats, three spots were increased two-fold or more (vs. control rats) in two-dimensional differential in-gel electrophoresis (2D-DIGE). The increased proteins were identified, by matrix-assisted laser desorption ionization time of flight (MALDI-TOF), as one isoform of heat shock protein 70 (HSP70) and two isoforms of protein disulfide isomerase associated 3. This result was confirmed by Western blotting analysis of 2D-PAGE. Conceivably, HSP70 and PDIA3 may play roles in modulating the lung structural remodeling that occurs due to pulmonary hypertension in hypobaric hypoxia.
    Histology and histopathology 01/2013; · 2.28 Impact Factor
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    ABSTRACT: It is difficult to distinguish desmoplastic malignant mesothelioma (DMM) from fibrous pleuritis (FP). We investigated the utility of immunohistochemistry as a way of differentiating between DMM and FP. We examined 11 DMMs and 46 FPs with the aid of antibodies against 18 cytokeratin (CK) subtypes, calponin, caldesmon, desmin, and GLUT-1. The best sensitivity and specificity cut-off values in the receiver operating characteristic curves (ROC) for CKs 7, 8, 17, 18, and 19, and GLUT-1 were each above 60%. When cases with either DMM or FP were partitioned by the staining score associated with the best sensitivity and specificity cut-off values in ROC, the incidence of a positive expression for CKs 7, 8, 17, 18, and 19, and GLUT-1 was significantly higher in DMM than in FP. In conclusion, immunohistochemistry for CKs 7, 8, 17, 18, and 19, and GLUT-1 may be useful, alongside histological characteristics, for separating DMM from FP.
    Histology and histopathology 12/2012; · 2.28 Impact Factor
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    ABSTRACT: Some studies have indicated that dietary cholesterol has a role in the progression of liver fibrosis. We investigated the mechanisms by which dietary cholesterol might contribute to hepatic fibrogenesis. C57BL/6 mice were fed a high-cholesterol diet or a control diet for 4 weeks; liver fibrosis then was induced by bile-duct ligation or carbon tetrachloride administration. Hepatic stellate cells (HSCs) were isolated from mice fed high-cholesterol diets or from Niemann-Pick type C1-deficient mice, which accumulate intracellular free cholesterol. After bile-duct ligation or carbon tetrachloride administration, mice fed high-cholesterol diets had significant increases in liver fibrosis and activation of HSCs compared with mice fed control diets. There were no significant differences in the degree of hepatocellular injury or liver inflammation, including hepatocyte apoptosis or Kupffer cell activation, between mice fed high-cholesterol or control diets. Levels of free cholesterol were much higher in HSCs from mice fed high-cholesterol diets than those fed control diets. In cultured HSCs, accumulation of free cholesterol in HSCs increased levels of Toll-like receptor 4 (TLR4), leading to down-regulation of bone morphogenetic protein and activin membrane-bound inhibitor (a pseudoreceptor for transforming growth factor [TGF]β); the HSCs became sensitized to TGFβ-induced activation. Liver fibrosis was not aggravated by the high-cholesterol diet in C3H/HeJ mice, which express a mutant form of TLR4; HSCs that express mutant TLR4 were not activated by accumulation of free cholesterol. Dietary cholesterol aggravates liver fibrosis because free cholesterol accumulates in HSCs, leading to increased TLR4 signaling, down-regulation of bone morphogenetic protein and activin membrane-bound inhibitor, and sensitization of HSC to TGFβ. This pathway might be targeted by antifibrotic therapies.
    Gastroenterology 01/2012; 142(1):152-164.e10. · 12.82 Impact Factor
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    ABSTRACT: Although B cells in vertebrates have been thought to lack phagocytic activity, there has been a recent report of such ability by the B cells of early vertebrates such as fish and frogs. Here, we show for the first time that mouse liver IgM(+) B cells actively phagocytose microsphere beads and Escherichia coli and that they effectively kill bacterial cells. Such phagocytic activity is not observed in other liver MNCs, except for F4/80(+) Kupffer cells. In the presence of fresh mouse serum (but not heat-inactivated serum), the heat-killed E. coli phagocytic activity of liver B cells increased significantly but was inhibited significantly by anticomplement component C3 antibody, suggesting E. coli opsonization by serum factors, including complement components. Upon i.v. injection of FITC-labeled E. coli into mice, a substantial proportion of liver B cells phagocytosed the bacteria, as compared with spleen B cells. Functional phagolysosome formation in liver B cells was supported by several reagents showing an acidic change and lysosomes in the phagocytosed vacuoles. Indeed, mouse liver B cells killed viable E. coli more efficiently than did spleen B cells in vitro. Further, E. coli-phagocytic liver B cells produced a substantial amount of IL-12. These results indicate that liver B cells have phagocytic and bactericidal activities similar to those of dedicated phagocytes and may contribute to bacterial clearance.
    Journal of leukocyte biology 11/2011; 91(4):537-46. · 4.99 Impact Factor
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    ABSTRACT: The experimental pulmonary hypertension that develops in hypobaric hypoxia is characterized by structural remodeling of the heart. The P2X4 receptor (P2X4R) controls vascular tone and vessel remodeling in several blood vessels, and it has emerged as a key factor in the enhancement of cardiovascular performance. To study the possible effects of hypobaric hypoxia on the P2X4R-synthesis system, 150 male Wistar rats were housed in a chamber at the equivalent of the 5,500 m altitude level for 21 days. After 14 days' exposure to hypobaric hypoxia, pulmonary arterial pressure (PAP) was significantly increased. In the right ventricle (RV) of the heart, P2X4R expression was significantly increased on days 1 and 14 (mRNA) and on days 7 and 21 (protein) of hypobaric hypoxic exposure. Immunohistochemical staining for P2X4R protein became more intense in RV in the late phase of exposure. These changes in P2X4R synthesis in RV occurred alongside the increase in PAP. In addition, P2X1R and P2Y2R mRNA levels in the RV were significantly increased on days 1, 14, and 21, and day 5, respectively, of exposure. The level of P2X1R protein in the RV was significantly increased on day 21 of exposure. Conceivably, P2 receptors, including P2X4R and P2X1R, might play roles in modulating the RV hypertrophy that occurs due to pulmonary hypertension in hypobaric hypoxia.
    Circulation Journal 03/2011; 75(4):945-54. · 3.58 Impact Factor
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    ABSTRACT: To assess whether early lung cancer prediction might be informed by an mRNA assay for 5-fluorouracil pathway genes in peripheral blood mononuclear cells (PBMNCs), we examined specimens taken from 51 adenocarcinoma patients and 38 controls (including six patients with benign tumors). PBMNCs and tumor-tissue specimens were taken for measurement of the mRNAs of various 5-fluorouracil pathway genes [thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD), thymidine phosphorylase (TP), and orotate phosphoribosyl transferase (OPRT)]. By quantitative RT-PCR, all four mRNAs were detected in both PBMNCs and tumor tissues. In PBMNCs, TS mRNA/GAPDH mRNA levels were significantly higher in adenocarcinoma patients than in the controls, and significantly higher for pathological stages 2-4 and lymph-node involvement pN1-pN3 than for pathological stage 1 and pN0, respectively. No correlation between PBMNCs and tumor-tissue specimens was found for the level of any mRNA. Thus, the measurement of TS mRNA in PBMNCs might aid the diagnosis of lung adenocarcinoma.
    Lung cancer (Amsterdam, Netherlands) 02/2011; 71(2):199-204. · 3.14 Impact Factor
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    ABSTRACT: Liver Kupffer cells have been suggested to be heterogeneous macrophage lineage cells. We explored this possibility by classifying the mouse Kupffer cells into subpopulations and characterizing them by their phenotype and function. Liver mononuclear cells (MNCs) from C57BL/6 mice were isolated and their phenotypes and functions were analyzed. The effects of clodronate liposomes and gadolinium chloride (GdCl(3)) on Kupffer cells were also investigated. Approximately 25% of liver MNCs were F4/80(+) Kupffer cells. Of these, 46% were CD11b(-)CD68(+), 22% were CD11b(+)CD68(-), and 6% were CD11b(+)CD68(+). CD68(+) cells showed potent phagocytic activity and reactive oxygen species (ROS) production capacity after lipopolysaccharide (LPS) stimulation, whereas CD11b(+) cells did not. CD11b(+) cells showed a strong capacity for the production of cytokines (TNF and IL-12), which was much less prominent in CD68(+) cells. At 24h after LPS or Escherichia coli injection into mice, the proportions of CD11b(+)CD68(-) and CD11b(+)CD68(+) cells increased but that of CD11b(-)CD68(+) cells decreased. The increase in CD11b(+)CD68(+) cells appeared to be derived from the CD11b(+)CD68(-) subset. Although the CD11b(+) cells augmented phagocytic activity after LPS injection, they did not increase ROS production, suggesting their weak lytic activity. Injection of clodronate or GdCl(3) into mice depleted the CD68(+) cells but increased CD11b(+) cells proportionally because CD68(+) cells may phagocytose these toxic reagents and undergo apoptosis. GdCl(3)-treated mice also consistently increased serum TNF after LPS challenge. Two F4/80(+) Kupffer cell subsets may exist, a CD68(+) subset with phagocytic activity and a CD11b(+) subset with cytokine-producing capacity.
    Journal of Hepatology 11/2010; 53(5):903-10. · 9.86 Impact Factor
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    ABSTRACT: To examine glucose-regulated protein 78 (GRP78; a major molecular chaperone at the endoplasmic reticulum, strongly expressed in several tumours) expression in urothelial carcinoma (UC) of the upper urinary tract (UUT) and to evaluate the diagnostic and progressive importance of GRP78 expression in UC-UUT. We investigated GRP78 expression (using immunohistochemistry) in 126 UC-UUTs to assess its relevance to progression. GRP78 overexpression was recognised in 23 (18.3%) of tumour samples. There was no association between GRP78 overexpression and clinicopathological findings, except for an association with low grade in invasive tumours. GRP78 overexpression significantly improved the disease-free survival rate in all patients (according to univariate and multivariate analyses), but did not alter the overall survival rate. The detection of GRP78 overexpression would appear to provide valuable information for the prognosis of UC-UUT.
    BJU International 09/2010; 106(6):873-8. · 3.05 Impact Factor
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    ABSTRACT: Lymphohistiocytoid mesothelioma (LHM), reported to be a rare variant of sarcomatoid mesothelioma, is challenging to differentiate from non-Hodgkin's lymphoma due to marked lymphocytic infiltration. To aid accurate recognition of LHM, we examined immunohistochemical, in situ hybridization (ISH) of Epstein-Barr virus RNA (EBER-1) mRNA, fluorescence ISH (FISH) for homozygous deletion of 9p21, and asbestos analysis in four cases (three men and 1 woman). Three patients died, while Case 4 was still alive 19 months after extrapleural pneumonectomy. Histologically, these cases were characterized by heavy lymphocytic infiltration. All neoplastic cells were positive for calretinin, AE1/AE3, and epithelial membrane antigen, but negative for CEA. EBER1 factor was negative. FISH analysis demonstrated homozygous deletion of the 9p21 locus in three of the four cases. In Case 1: (i) autopsy findings showed mesothelioma primarily located in the right parietal pleura, but metastasized into the left lung and abdominal organs; (ii) the histological findings at autopsy indicated sarcomatoid mesothelioma; and (iii) we found asbestos bodies and fibers in extracts from lung tissue (Cases 1 & 4) using digestion with bleaching fluid. LHM, an infrequent variant of sarcomatoid mesothelioma, displayed homozygous deletion of the 9p21 locus (three of four cases), and has a relatively favorable prognosis for the sarcomatoid type.
    Pathology International 08/2010; 60(8):566-74. · 1.72 Impact Factor
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    ABSTRACT: While bone marrow or stem cell transplantation can rescue bone marrow aplasia in patients accidentally exposed to a lethal radiation dose, radiation-induced irreversible gastrointestinal damage (GI syndrome) is fatal. We investigated the effects of ascorbic acid on radiation-induced GI syndrome in mice. Ascorbic acid (150 mg/kg/day) was orally administered to mice for 3 days, and then the mice underwent whole body irradiation (WBI). Bone marrow transplantation (BMT) 24 h after irradiation rescued mice receiving a WBI dose of less than 12 Gy. No mice receiving 14 Gy-WBI survived, because of radiation-induced GI syndrome, even if they received BMT. However, pretreatment with ascorbic acid significantly suppressed radiation-induced DNA damage in the crypt cells and prevented denudation of intestinal mucosa; therefore, ascorbic acid in combination with BMT rescued mice after 14 Gy-WBI. DNA microarray analysis demonstrated that irradiation up-regulated expressions of apoptosis-related genes in the small intestine, including those related to the caspase-9-mediated intrinsic pathway as well as the caspase-8-mediated extrinsic pathway, and down-regulated expressions of these genes in ascorbic acid-pretreated mice. Thus, pretreatment with ascorbic acid may effectively prevent radiation-induced GI syndrome.
    Journal of Radiation Research 12/2009; 51(2):145-56. · 1.45 Impact Factor
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    ABSTRACT: Aim:  Protein kinase C (PKC), cloned as a serine/threonine kinase, plays key roles in diverse intracellular signalling processes and in cardiovascular remodelling during pressure overload or volume overload. We looked for correlations between changes in PKC isoforms (levels and/or subcellular distributions) and cardiac remodelling during experimental hypobaric hypoxic environment (HHE)-induced pulmonary hypertension.Methods:  To study the PKC system in the heart during HHE, 148 male Wistar rats were housed for up to 21 days in a chamber at the equivalent of 5500 m altitude level (10% O2).Results:  At 14 or more days of exposure to HHE, pulmonary arterial pressure (PAP) was significantly increased. In the right ventricle (RV): (1) the expression of PKC-α protein in the cytosolic and membrane fractions was increased at 3–14 days and at 5–7 days of exposure respectively; (ii) the cytosolic expression of PKC-δ protein was increased at 1–5, 14 and 21 days of exposure; (3) the membrane expressions of the proteins were decreased at 14–21 (PKC-βII), 14–21 (PKC-γ), and 0.5–5 and 21 (PKC-ε) days of exposure; (4) the expression of the active form of PKC-α protein on the plasma membrane was increased at 3 days of exposure (based on semiquantitative analysis of the immunohistochemistry). In the left ventricle, the expressions of the PKC mRNAs, and of their cytosolic and membrane proteins, were almost unchanged. The above changes in PKC-α, which were strongly evident in the RV, occurred alongside the increase in PAP.Conclusion:  PKC-α may help to modulate the right ventricular hypertrophy caused by pulmonary hypertension in HHE.
    Acta Physiologica 11/2009; 198(4):431 - 440. · 4.38 Impact Factor
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    ABSTRACT: Reported herein is a case of malignant pleural mesothelioma, initially diagnosed on cervical lymph node biopsy. A 58-year-old man, without obvious evidence of asbestos exposure, exhibited repeated pleural effusion (cause unclear), which was resolved by diuretics. A neck mass was apparent and was identified pathologically as a lymph node metastasis of malignant mesothelioma. F-18 fluorodeoxyglucose positron emission tomography/CT established the diagnosis of malignant pleural mesothelioma. Two conclusions emerge from this report: (i) cervical lymph node metastasis of pleural mesothelioma, although rare, should be included in differential diagnosis; and (ii) positron emission tomography/CT is useful for establishing a diagnosis of mesothelioma.
    Pathology International 09/2009; 59(8):592-4. · 1.72 Impact Factor
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    ABSTRACT: System l-amino acid transport mediates the uptake of aromatic neutral amino acids and nutritionally essential amino acids from extracellular fluids. Little is known about the role of l-amino acid transporter 1 (LAT1), a member of the system l-amino acid transporter family, in non-small-cell lung carcinomas (NSCLCs). We examined (i) LAT1 mRNA levels in 40 normal lung tissues (NLTs) and 237 NSCLCs using semiquantitative RT-PCR, (ii) LAT1 protein expression in 295 NSCLCs using immunohistochemistry, and (iii) whether LAT1 mRNA and protein expressions were related to clinicopathologic findings and outcome. The LAT1 mRNA level was significantly higher in all NSCLCs (6.81+/-1.13) than in NLT (1.00+/-0.18). The LAT1 mRNA level showed no association with clinicopathologic findings or outcome. LAT1 protein was detected with a diffuse or granular appearance within the cytoplasm and/or on the plasma membrane of tumor cells. When tumors were graded as positive if staining indicating a plasma membrane expression of LAT1 protein made up more than 10% of the tumor, the frequency of this membrane expression was found to be associated with tumor histology, differentiation grade, pathologic stage, T classification, pleural invasion, lymph-vessel invasion, and overall survival rate. Detection of a plasma membrane expression of LAT1 protein would appear to be of value in informing the prognosis in NSCLC cases.
    Lung cancer (Amsterdam, Netherlands) 07/2009; 68(1):58-65. · 3.14 Impact Factor
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    ABSTRACT: Thromboangiitis obliterans (TAO, Buerger's disease) is an idiopathic, recurrent, segmental, nonatherosclerotic, inflammatory, occlusive vascular disease with a poorly understood pathogenesis. Intestinal or multi-organ involvement is rare. Recent immunohistochemical analyses of ordinary TAO have indicated an inflammatory and immunologic pathogenesis. We report a case of TAO involving multiple large vessels. By immunohistochemistry, CD3+ T cells were revealed around the recanalization sites within the abdominal aorta. CD4+ T cells were almost equal in number to CD8+ T cells. These findings indicate the participation of inflammatory and immunologic processes in TAO with multi-organ involvement (as in ordinary TAO).
    Cardiovascular pathology: the official journal of the Society for Cardiovascular Pathology 02/2009; 19(1):59-62. · 1.63 Impact Factor
  • Haigan 01/2009; 49(1):25-29.
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    ABSTRACT: The contacts between epithelial cells are maintained mainly by adherens junctions and tight junctions (TJs). However, the role of TJ proteins in cancer is not well understood. We studied the expression of occludin and 4 claudins to assess their importance in the progression of urothelial carcinoma of the upper urinary tract (UC-UUT). In 129 cases, we examined their expression using immunohistochemical analysis and also their relationships to clinicopathologic parameters and clinical outcome. Positive expression of occludin and claudins 1, 3, 4, and 7 were recognized in 117 (90.7%), 113 (87.6%), 95 (73.6%), 127 (98.4%), and 123 (95.3%) of tumor samples, respectively. Claudin-3 expression was significantly associated with stage, grade, and pattern of growth. Claudins 1 and 4 expression was significantly associated with stage. However, neither occludin nor claudin-7 expression was associated with clinicopathologic findings. When tumors with scores below the median for a given protein were classified as the "low expression group," univariate analysis of overall survival revealed that claudins 1 and 3 had a significant effect on overall survival. Detection of claudins 1, 3, and 4 would seem to provide valuable information about the progression of UC-UUT.
    American Journal of Clinical Pathology 08/2008; 130(1):43-9. · 2.88 Impact Factor
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    ABSTRACT: Experimental pulmonary hypertension induced in a hypobaric hypoxic environment (HHE) is characterized by structural remodelling of the heart and pulmonary arteries. Osteopontin (OPN) has emerged as a key factor in cardiovascular remodelling in response to pressure or volume overload. We studied the possible effects of HHE on the OPN synthesis system. One hundred and forty-eight male Wistar rats were housed in a chamber with conditions equivalent of an altitude of 5500 m for up to 21 days. Plasma OPN protein level was found to be significantly decreased on day 0.5 of exposure to HHE, as was the level in the adrenal gland (which secreted highest levels of OPN protein). In the right ventricle of the heart (mRNA) and the lung (protein), OPN expression was found to be significantly increased only on day 1 and day 5, respectively, of exposure to HHE. By immunohistochemistry, the distribution and intensity of OPN protein in several organs were found to alter during exposure to HHE. However, these changes in OPN synthesis did not coincide with the moderate increase in pulmonary arterial pressure (PAP) (maximal mean PAP, 24.5 mmHg) during HHE. Pulmonary hypertension in HHE with conditions equivalent of an altitude of 5500 m may induce little or no OPN in heart and lung. Sustained induction may require a more severe PAP overload.
    Acta Physiologica 08/2008; 193(3):291-301. · 4.38 Impact Factor
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    ABSTRACT: The level of serum CCL5, a C-C chemokine, is reportedly correlated with tumor progression in several cancers. We herein investigated the mechanisms by which CCL5 might contribute to tumor progression in gastric cancer. Serum CCL5 levels significantly correlated with tumor progression and prognosis in patients with gastric cancer. Immunohistochemistry showed that tumor-infiltrating lymphocytes expressed CCL5, while the tumor cells expressed the CCL5 receptors. Fluorescent double staining showed that tumor-infiltrating CD4+ cells rather than CD8+ cells preferentially expressed CCL5. Using gastric cancer cell lines (MKN45, KATO III), we examined CCL5 production by coculturing whole peripheral blood mononuclear cells (PBMCs), CD4+ cells, or CD8+ cells, with tumor cells. CD4+ cells cocultured with tumor cells remarkably enhanced CCL5 production in a direct cell-cell contact manner over other cocultured PBMCs, including CD8+ cells. Gastric cancer cell lines expressed CCL5 receptors and augmented their proliferation in response to CCL5 stimulation. Furthermore, we examined the effect of CCL5-treated cancer cells on the cocultured PBMCs, focusing on the CD4+/CD8+ proportion and apoptosis. Coculture of CCL5-treated gastric cancer cells with PBMCs resulted in a significant decrease in the proportion of CD8+ cells but not CD4+ cells, suggesting Fas-FasL-mediated apoptosis in CD8+ cells. In immunodeficient mice coinjected with KATO III and PBMCs, neutralization of CCL5 significantly suppressed tumor progression, resulting in a favorable outcome. In conclusion, gastric cancer cells might thus induce CD4+ T cells to secrete CCL5 and exploit it for their progression, as well as to aid in the prevention of CD8+ T cell-involved tumor elimination.
    International Journal of Cancer 07/2008; 122(11):2535-41. · 6.20 Impact Factor

Publication Stats

1k Citations
207.48 Total Impact Points

Institutions

  • 1997–2014
    • National Defense Medical College
      • • Department of Laboratory Medicine
      • • Division of Otorhinolaryngology
      • • Division of Environmental Medicine
      • • Division of Pathology
      Tokorozawa, Saitama, Japan
  • 2009
    • Kobe University
      • Division of Molecular Pharmacology and Pharmacogenomics
      Kōbe, Hyōgo, Japan
  • 1999–2000
    • Tokyo Medical and Dental University
      • Medical Research Institute
      Tokyo, Tokyo-to, Japan