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Biomedical subjects

O Tokunaga

Publications and source records attributed to O Tokunaga.

At least 19 recordsLinked to original sources

Expression of the hepatocyte growth factor/c-Met pathway is increased at the cancer front in breast carcinoma.

Expression of hepatocyte growth factor (HGF) and c-Met (HGF receptor) has been reported in many neoplasms. We investigated coexpression of HGF and c-Met to determine the role of the HGF/c-Met pathway in breast carcinoma, especially at the cancer front. Eighty-eight cases of carcinoma of the breast were studied by immunohistochemistry and by in situ hybridization for HGF and c-Met expression. The staining pattern was termed "front accentuation pattern" when it was most conspicuous at the cancer front. HGF and c-Met proteins were expressed in cancer and stromal cells, with autocrine and paracrine patterns. The front accentuation pattern of c-Met was observed in cancer cells, but not in stromal cells. The front accentuation pattern was not observed in HGF. Coexpression of HGF and c-Met at the cancer front was correlated with histologic grade, reduced patient survival and a high Ki-67 labeling index. Our findings suggest that the HGF/c-Met pathway acts primarily as a mitogen, especially at the cancer front, in a paracrine manner and affects some clinical factors, including patient survival.

Adult↗

Composite glandular-endocrine cell carcinoma of the common bile duct.

A rare case of composite glandular-endocrine cell carcinoma of the common bile duct is presented. Histologically, this tumor consisted of adenocarcinoma and small-cell neuroendocrine carcinoma, with a transition between the two components. The two distinct areas of the tumor were immunohistochemically different, whereas the transitional zone exhibited characteristics of both areas. These features suggest that the tumor arose from a multipotential stem cell. Although it has been reported that the presence of neuroendocrine differentiation in carcinomas indicates a poor prognosis, the patient in the present case was well at the time of writing this report. This may be due to the fact that adenocarcinoma, which characteristically has a low proliferative activity, constituted the majority of the tumor.

Adenocarcinoma↗

Critical role of type IV collagens in the growth of bile duct carcinoma. In vivo and in vitro studies.

Most extrahepatic bile duct carcinomas (EBDC) are characterized by a striking stromal response (desmoplasia). Our previous studies showed deposition of type IV collagen in the desmoplastic stroma beyond the basement membrane. Although type IV collagen is expressed in EBDC, little is known about the pattern of deposition in tumor stroma and how this matrix component influences the behavior of tumor cells. With the progression of desmoplasia in EBDC, different changes occurred in the quantity and localization of type IV collagen from that of type I collagen. Type I collagen was diffusely distributed in the stroma and appeared to be concentrated in the center of the tumors. In contrast, type IV collagen was deposited in the interstitium alongside carcinoma cells at the tumors' periphery. Weak or no type IV collagen deposition was detected in the more central portion of the tumors containing sclerotic collagens. To investigate the role of stromal type IV collagen in tumor cell proliferation, EBDC cell lines were cultured in a three-dimensional matrix containing varying compositions of type I collagen and type IV collagen. They were also assayed for cell adhesion and migration using in vitro models. Type IV collagen more extensively stimulated tumor cell proliferation, adhesion and migration in a dose-dependent manner than did type I collagen. All of these results suggest that modified tumor stroma with the presence of type IV collagen in EBDC provides a better environment for tumor growth and invasion.

Adenocarcinoma↗

Radiographic observation of a case of gastrointestinal stromal tumor in stomach.

A case of gastrointestinal stromal tumor (GIST) in stomach was presented. Serial barium meal x-ray examinations revealed an enlarging elevated lesion on the fornix of the stomach. Tumor volume doubling time was found to be 299 days. Microscopic and immunohistochemical studies of the resected tumor disclosed GIST, uncommitted type, low grade malignant/potentially malignant. A radiographic feature of this rare type of gastric submucosal tumor was demonstrated in this report.

Female↗

Angiogenesis and mast cells in non-Hodgkin's lymphoma: a strong correlation in angioimmunoblastic T-cell lymphoma.

Mast cells are likely to play a role in angiogenesis under pathological conditions. Solid tumor growth is dependent on angiogenesis, but the influence of mast cells on angiogenesis in non-Hodgkin's lymphoma, (NHL) is not clear. We investigated mast cell number and vessel count in 61 cases of NHL. We also evaluated expression of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF), both important cytokines for angiogenesis. The number of mast cells was greater in T-cell lymphomas than in B-cell lymphomas. Of the T-cell lymphomas, the greatest number of mast cells was observed in the angioimmunoblastic T-cell lymphoma (AIL). In all NHLs, significant correlation was found between vessel count and the number of mast cells (p < 0.0001) and between vessel count and the number of VEGF-expressing cells (p < 0.05) but not between vessel count and bFGF-expressing cells. Strong correlation was detected between the number of mast cells and the number of VEGF-expressing cells (p < 0.0001) in all NHLs. Double fluorescence staining of VEGF mRNA and mast cell tryptase revealed that mast cells expressed VEGF mRNA. Our data suggest that mast cells play a very important role in angiogenesis by expressing VEGF in NHL, especially in AIL.

Cell Count↗

Dimethyl dioctadecyl ammonium bromide (DDA)-induced arthritis in rats: a model of experimental arthritis.

A single intradermal injection of 2 mg of dimethyl dioctadecyl ammonium bromide (DDA) in phosphate buffered saline (PBS) could induce polyarthritis in both LEW and DA rats with low incidence and severity whereas 2 mg of DDA in incomplete Freund's adjuvant (IFA) could induce very severe polyarthritis with 100% incidence in LEW rats. Histology of DDA-induced arthritis (DIA) revealed cellular infiltration, synovial hypertrophy, development of granulation tissue, destruction of cartilage and bone deformation in the articular joints. Lymph node cells (LNCs) but not immunoglobulin fractions from the DIA rats successfully transferred the severe disease into the naive recipients. A challenge injection of DDA in IFA in the rats, which had recovered from the DIA, could reactivate the disease. It is thus concluded that DDA has arthritis-inducing ability in the rats which is potentiated by IFA and the DIA is a cell-mediated immune disease which might be a model of experimental arthritis.

Adjuvants, Immunologic↗

B-cell lymphoma-associated hemophagocytic syndrome: clinicopathological characteristics.

Seven patients with peripheral B-cell lymphoma associated with hemophagocytic syndrome are reported. In all cases, the histologic subtype was diffuse large B-cell lymphoma. Hemophagocytic features were noted in the bone marrow with lymphomatous infiltration. Hemophagocytic syndrome occurred with presentation of the lymphoma and was characterized by high fever, cytopenias, and elevated levels of lactate dehydrogenase, ferritin, C-reactive protein, and cytokines [interferon gamma, macrophage colony-stimulating factor, soluble interleukin (sIL)-2R, and IL-6] without evidence of infection. The phenotypes of lymphomas were suspected CD19+, CD20+, S-Ig+, CD10-, and coexpression of CD5 in some cases. Flow cytometric analysis showed a low CD4/CD8 ratio in peripheral blood and bone marrow. We suggest that the pathogenesis of hemophagocytic syndrome is hypercytokinemia induced by a proliferation of reactive CD8+ T cells. Previous reports of B-cell lymphoma with hemophagocytic syndrome demonstrated similar clinical manifestations and poor prognoses. The invasion patterns of these diffuse large B-cell lymphomas with hemophagocytosis may be classified into three groups: microscopic lymph-node involvement type, gross lymph-node involvement type, and splenic lymphoma type. Although hemophagocytic syndromes have been reported to be associated with T-cell lymphomas, our results indicate an association with diffuse large B-cell lymphoma.

Aged↗

Primary intestinal T-cell lymphoma resembling lymphomatous polyposis: report of a case.

We report an interesting case of primary intestinal T-cell lymphoma (ITL) resembling lymphomatous polyposis (LP) in a 24-year-old man. The neoplasm macroscopically showed numerous small polyps throughout the colon and microscopically showed diffuse proliferation of small-sized tumor cells with occasionally cleaved or irregularly shaped nuclei. The tumor cells were immunohistochemically positive for CD3, CD8, TIA-1, and CD56, and a polymerase chain reaction study showed a single band, indicating monoclonal rearrangement of the T-cell receptor beta gene. The phenotypic features in the current case are consistent with those of ITL derived from cytotoxic CD56+ CD8+ intraepithelial lymphocytes. This is the second documented case of primary ITL with a morphologic pattern of LP.

Adult↗

Phlegmonous colitis: a specific and severe complication of chronic hepatic disease.

Phlegmonous colitis (PC) is an acute infectious entity caused by bacteria. In this study, we reviewed 8,822 autopsy cases and found 13 cases of PC (0.15%). PC affected 2.43% of patients with hepatic cirrhosis or subacute liver atrophy, both of which were considered to be due to hepatitis viral infection. Before autopsy, none of the cases studied was suspected to involve PC, irrespective of the immediate cause of patient death. Thirteen autopsy cases showed some or all of the following pathohistologic characteristics: (1) involvement of the cecum (9 cases, 76.9%), (2) phlegmonous inflammatory changes and edema in the submucosa (100%), (3) bacterial infection (100%), (4) no microscopically detectable mucosal injuries (12 cases, 92.3%), and (5) acute serositis (peritonitis) (2 cases, 15.4%). These results suggest that PC is an unrecognized, but fatal complication of patients with some hepatic diseases and that PC has pathohistologic characteristics in common with previously reported spontaneous bacterial peritonitis in animal models. PC probably arises due to spontaneous infection in patients with hepatic cirrhosis.

Adult↗

Association of vascular endothelial growth factor and mast cells with angiogenesis in laryngeal squamous cell carcinoma.

We investigated the expression of vascular endothelial growth factor (VEGF) and microvascular density in 54 cases of invasive laryngeal squamous cell carcinoma (SCC) and in ten samples of normal laryngeal tissue using immunohistochemistry methods. The study also focused on the distribution of mast cells in and around the SCCs. The microvascular density in laryngeal carcinoma tissue was higher than that in normal tissue (P = 0.02). VEGF was localized in SCCs, stromal cells, endothelial cells, minor salivary glands, and non-cancer epithelium adjacent to the tumor. VEGF expression in the tumor cells was found in 13 of 54 cases (24.1%), whereas mast cells around the carcinomas were VEGF positive in all 54 cases. Staining of VEGF in SCCs was strong in the area of high microvascular density (P = 0.0002). Using a multi-labeling subtraction immunostaining method, VEGF-positive stromal cells were classified mostly as mast cells and, in a few instances, as macrophages. VEGF staining in SCCs was associated with the mast cell count (P = 0.0001). There was no distinct correlation between VEGF expression and pTNM stage of an SCC. In conclusion, the results suggest that VEGF might be an important angiogenic factor in cancer invasion. Laryngeal cancer cells and mast cells may control the angiogenic response by releasing VEGF.

Adult↗

Precancerous conditions of gallbladder carcinoma: overview of histopathologic characteristics and molecular genetic findings.

Two distinct epithelial lesions (dysplasia and adenoma) and one high-risk condition (anomalous pancreatico-biliary ductal junction; APBDJ) are currently recognized as premalignant stages of gallbladder carcinogenesis. In addition to clinicopathologic observations, recent molecular genetic studies have provided further insight into the pathogenesis and biological behavior of these precursor lesions. In this review, we concentrate on describing the histopathologic and clinicopathologic background and recent molecular genetic findings for each of these putative precursor lesions.

Adenoma↗

Abnormal distribution of collagen type IV in extrahepatic bile duct carcinoma.

The present study investigated the pathogenesis of desmoplastic stroma formation, which is characteristic of most bile duct carcinomas and other scirrhous carcinomas. Using immunohistochemical analysis, the expression of collagen types I and IV, laminin and TGF-beta1 was examined in human extrahepatic bile duct carcinoma and compared with gastric and colon carcinoma. In addition to delineating the basement membranes of carcinoma nests and blood vessels, collagen type IV was present along the thick bundles of collagenous fibers in the stroma of extrahepatic bile duct carcinoma and scirrhous gastric carcinoma. The immunoreactivity of collagen type IV was strong in the adjacent or surrounding interstitium of tumor cell nests, but was absent or weak in older, more central portions of the tumor that contained sclerotic collagen. In situ hybridization demonstrated active expression of collagen alpha1(IV) mRNA in extrahepatic bile duct carcinoma and scirrhous gastric carcinoma cells. These results suggest that, although collagen type IV is typically a component of the basement membrane, it is expressed in the interstitial stroma of extrahepatic bile duct carcinoma and scirrhous gastric carcinoma where it may play a role in desmoplastic stroma formation.

Adenocarcinoma↗

Breast masses with peripheral rim enhancement on dynamic contrast-enhanced MR images: correlation of MR findings with histologic features and expression of growth factors.

PURPOSE: To investigate the histologic bases of rim enhancement of breast masses demonstrated on dynamic contrast material-enhanced magnetic resonance (MR) images. MATERIALS AND METHODS: Dynamic MR images of breast lesions (invasive carcinoma, n = 29; other, n = 6) in 35 women were reviewed. In each patient, subtraction images of the dynamic contrast-enhanced study were obtained, and early and delayed rim enhancement and delayed internal enhancement were evaluated. The MR findings were correlated with the ratio of microvessel density of the peripheral to the central portion of the lesion, fibrosis, and other histologic features, including expression of vascular endothelial growth factor (VEGF) and transforming growth factor ss1. RESULTS: Early rim enhancement was observed in 29% and delayed rim enhancement was noted in 60% of all patients. Small cancer nests, a high ratio of peripheral-to-central microvessel density, peripheral VEGF expression, and a low ratio of peripheral-to-central fibrosis were correlated with early rim enhancement. Delayed rim enhancement was correlated with a high degree of fibrosis and inflammatory changes. Delayed internal enhancement was correlated with a high degree of fibrosis. CONCLUSION: Rim enhancement of breast lesions at MR imaging is due to a combination of angiogenesis, distribution and degree of fibrosis, expression pattern of VEGF, and various histologic features.

Adenocarcinoma, Mucinous↗

The endothelial cell protein C receptor (EPCR) functions as a primary receptor for protein C activation on endothelial cells in arteries, veins, and capillaries.

Plasma protein C functions as an anticoagulant when it is converted to the active form of serine protease. Protein C activation has been found to be mediated by the endothelial cell surface thrombin/thrombomodulin (TM) complex. In addition, we recently identified the endothelial cell protein C/activated protein C receptor (EPCR) which is capable of high-affinity binding for protein C. In this study, we established monoclonal antibodies (mAbs) against EPCR including several function blocking antibodies. Immunohistochemical analysis using these mAbs demonstrated that EPCR is widely expressed in the endothelial cells of arteries, veins, and capillaries in the lung, heart, and skin. Function blocking anti-EPCR mAbs strongly inhibited protein C activation mediated by primary cultured arterial endothelial cells which express abundant EPCR. Anti-EPCR mAbs also prevent protein C activation mediated by microvascular endothelial cells. These results indicate that EPCR functions as an important regulator for the protein C pathway in various types of vessels.

Antibodies, Monoclonal↗

The preventive effects of incomplete Freund's adjuvant and other vehicles on the development of adjuvant-induced arthritis in Lewis rats.

The present study showed a novel finding that the development of adjuvant-induced arthritis (AA) in Lewis rats was completely prevented by incomplete Freund's adjuvant (IFA) injected 21 or 28 days before complete Freund's adjuvant (CFA) challenge. Hexadecane also completely prevented AA and squalane, methyl oleate and pristane moderately prevented AA, though pristane by itself induced mild arthritis in two out of five rats. Concanavalin A-stimulated lymph node cells (LNCs) isolated from AA rats were able to adoptively transfer the severe polyarthritis to all the naive recipients or even to the IFA pretreated recipients with earlier onset and more rapid progression than those of AA. The LNCs from the donors who had been pretreated with IFA and subsequently challenged with CFA could induce mild arthritis in only two out of eight naive recipients, whereas all the recipients who were challenged with CFA immediately after intravenous injection of these LNCs developed significantly less severe arthritis. However, the LNCs from IFA-pretreated donors failed to prevent AA. According to the T helper type 1 (Th1)/Th2 paradigm, it was suggested that the adjuvant-active vehicles such as IFA, hexadecane, squalane, methyl oleate and pristane, can affect and deviate the Th1/Th2 balance of immune responses in host. CFA could promote the propagation of Th2 cells rather than Th1 cells in these vehicle-pretreated rats through as yet undetermined mechanisms, eventually resulting in the prevention of AA. Finally, we discussed a regulatory role of adjuvant vehicles for induction and suppression of AA.

Adoptive Transfer↗

A case of ALK-positive large T-cell lymphoma expressing epithelial membrane antigen with favorable prognosis.

We describe the case of a 59-year-old woman with Ki-1-negative, T cell-type, anaplastic lymphoma kinase (ALK)-positive large cell lymphoma that was positive for epithelial membrane antigen. She was histopathologically diagnosed as having a metastatic undifferentiated carcinoma from a cervical lymph node biopsy. Clinical and radiographic studies revealed no other primary tumor. The patient underwent a left radical neck dissection. Surgically resected lymph nodes revealed an ALK1-positive large cell lymphoma. Thereafter the patient has had an unusually favorable prognosis.

Anaplastic Lymphoma Kinase↗