Pathological Significance (pathological + significance)

Distribution by Scientific Domains


Selected Abstracts


Pathological significance of vascular endothelial growth factor A isoform expression in human cancer

PATHOLOGY INTERNATIONAL, Issue 5-6 2002
Masato Nakamura
Vascular endothelial growth factor (VEGF) is a highly specific factor for vascular endothelial cells. Five VEGF-A isoforms (splice variants 121, 145, 165, 189 and 206) are generated as a result of alternative splicing from a single VEGF-A gene. These differ in their molecular weights and in biological properties such as their ability to bind to cell-surface heparan sulfate proteoglycans. Deregulated VEGF-A expression contributes to the development of solid tumors by promoting tumor angiogenesis. More specifically, VEGF-A189 expression is related to angiogenesis and prognosis in certain human solid tumors. VEGF-A189 expression is also related to the xenotransplantability of human cancers into immunodeficient mice in vivo. Consequently, inhibition of VEGF-A or VEGF-A189 signaling regulates the development and metastasis of a variety of tumors. This review focuses on recent studies of the mechanisms by which VEGF-A regulates angiogenesis in the cancer stroma and on our recent findings concerning the potential mechanisms of VEGF-A189 expression on tumor growth and metastasis. [source]


Expression of Pit2 sodium-phosphate cotransporter during murine odontogenesis is developmentally regulated

EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 6 2006
Dawei Zhao
Different sodium-dependent inorganic phosphate (Pi) uptake mechanisms play a major role in cellular Pi homeostasis. The function and detailed distribution patterns of the type III Na+ -phosphate cotransporter, PiT-2, in different organs during development are still largely unknown. We therefore examined the temporospatial expression patterns of Pit2 during murine odontogenesis. Odontoblasts were always devoid of Pit2 expression, whereas a transient, but strong, expression was detected in young secretory ameloblasts. However, the stratum intermedium and, later on, the papillary layer and cells of the subodontoblastic layer, exhibited high levels of Pit2 mRNA, which increased gradually as the tooth matured. Hormonal treatment or Pi starvation of tooth germs in vitro did not alter Pit2 levels or patterns of expression, indicating mechanisms of regulation different from those of PiT-1 or other cell types. PiT-2 also functions as a retroviral receptor, and functional membrane-localized protein was confirmed throughout the dental papilla/pulp by demonstrating cellular permissiveness to infection by a gammaretrovirus that uses PiT-2 as a receptor. The distinct pattern of Pit2 expression during odontogenesis suggests that its Pi -transporter function may be important for homeostasis of dental cells and not specifically for mineralization of the dental extracellular matrices. The expression of viral receptors in enamel-forming cells and the dental pulp may be of pathological significance. [source]


Two subpopulations of thrombin-activated platelets differ in their binding of the components of the intrinsic factor X-activating complex

JOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 11 2005
M. A. PANTELEEV
Summary., Binding of fluorescein-labeled coagulation factors IXa, VIII, X, and allophycocyanin-labeled annexin V to thrombin-activated platelets was studied using flow cytometry. Upon activation, two platelet subpopulations were detected, which differed by 1,2 orders of magnitude in the binding of the coagulation factors and by 2,3 orders of magnitude in the binding of annexin V. The percentage of the high-binding platelets increased dose dependently of thrombin concentration. At 100 nm of thrombin, platelets with elevated binding capability constituted ,4% of total platelets and were responsible for the binding of ,50% of the total bound factor. Binding of factors to the high-binding subpopulation was calcium-dependent and specific as evidenced by experiments in the presence of excess unlabeled factor. The percentage of the high-binding platelets was not affected by echistatin, a potent aggregation inhibitor, confirming that the high-binding platelets were not platelet aggregates. Despite the difference in the coagulation factors binding, the subpopulations were indistinguishable by the expression of general platelet marker CD42b and activation markers PAC1 (an epitope of glycoprotein IIb/IIIa) and CD62P (P-selectin). Dual-labeling binding studies involving coagulation factors (IXa, VIII, or X) and annexin V demonstrated that the high-binding platelet subpopulation was identical for all coagulation factors and for annexin V. The high-binding subpopulation had lower mean forward and side scatters compared with the low-binding subpopulation (,80% and ,60%, respectively). In its turn, the high-binding subpopulation was not homogeneous and included two subpopulations with different scatter values. We conclude that activation by thrombin induces the formation of two distinct subpopulations of platelets different in their binding of the components of the intrinsic fX-activating complex, which may have certain physiological or pathological significance. [source]


Intratumoral lymphangiogenesis of esophageal squamous cell carcinoma and relationship with regulatory factors and prognosis

PATHOLOGY INTERNATIONAL, Issue 10 2008
Akemi Inoue
The clinical and pathological significance of intratumoral lymphangiogenesis (ITL) with human esophageal squamous cell carcinomas (ESCC) remains unclear, as does the role of signaling molecules such as vascular endothelial growth factor (VEGF)-A,C, platelet-derived growth factor (PDGF)-A, and p53, in the regulation of ITL. Lymphatic vessel density (LVD) was significantly increased in VEGF-A and VEGF-C immunohistochemical score 1 and 2,3 groups as compared to the score 0 group and also with high of VEGF-A, VEGF-C and PDGF-A mRNA expression. Both LVD and blood vessel density (BVD) were significantly greater in the p53 gene mutant group than in the wild-type group. Lymph node metastasis was significantly more frequent with than without ITL and Kaplan,Meier analysis indicated a significantly poorer prognosis. Multivariate analysis using Cox proportional hazard method showed that invasion depth, lymph node metastasis and ITL were independent prognostic factors. [source]


Subjective sleep quality and suggested immobilization test in restless leg syndrome and periodic limb movement disorder

PSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 3 2002
YUICHI INOUE md
Abstract The severity of restless leg syndrome (RLS) and/or periodic limb movement disorder (PLMD) was investigated by using a suggested immobilization test (SIT) and by measuring the influence of these disorders on the subjective sleep quality as assessed by the Pittsburgh Sleep Quality Index (PSQI). Patients with RLS and those with both RLS and PLMD showed remarkably high values for PSQI and SIT, whereas patients with PLMD only showed normal values for PSQI. These findings suggest that there is only a small pathological significance for periodic limb movements, and demonstrate the efficacy of SIT and PSQI for evaluating the severity of these disorders. [source]


Suppression of putative tumour suppressor gene GLTSCR2 expression in human glioblastomas,

THE JOURNAL OF PATHOLOGY, Issue 2 2008
Y-J Kim
Abstract Glioma tumour-suppressor candidate region gene 2 (GLTSCR2/PICT-1) is localized within the well-known 1.4 Mb tumour-suppressive region of chromosome 19q, which is frequently altered in various human tumours, including diffuse gliomas. Aside from its chromosomal localization, several lines of evidence, including PTEN-phosphorylating and cell-killing activities, suggests that GLTSCR2 participates in the suppression of tumour growth and development. However, little is known about the biological functions and molecular mechanisms of GLTSCR2 as a tumour suppressor gene. We investigated the pathological significance of GLTSCR2 expression in association with the development and progression of glioblastomas, the most common malignant brain tumour. We used real-time PCR and western blot analysis to examine the expression levels of GLTSCR2 mRNA and protein in glioblastomas, normal brain tissue and in non-glial tumour tissue of different origin, and found that GLTSCR2 expression is down-regulated in glioblastomas. In addition, direct sequencing analysis and fluorescence in situ hybridization clearly demonstrates the presence of genetic alterations, such as a nonsense mutation and deletion, in the GLTSCR2 gene in glioblastomas. Finally, our immunohistochemical study demonstrates that GLTSCR2 is sequentially down-regulated according to the histological malignant progression of the astrocytic glial tumour. Taken together, our results suggest that GLTSCR2 is involved in astrocytic glioma progression. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source]