Linked Life Data

17367605

Source:http://linkedlifedata.com/resource/pubmed/id/17367605

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2007-3-19
pubmed:abstractText
Carbonic anhydrase IX (CAIX) is a transmembrane enzyme involved in the reversible metabolism of carbon dioxide to carbonic acid and, hence, in physiological pH regulation. It also participates in cellular differentiation and proliferation, its expression being absent in most normal tissues. It has been recently postulated that the hypoxia-inducible factor (HIF-1) pathway up-regulated by hypoxia accounts for CAIX overexpression in most human tumors. In the present study, we examined the expression of this enzyme in diffuse gliomas of astrocytic origin in relation to vascular endothelial growth factor (VEGF) and HIF-1alpha expression, proliferation rate (as assessed with Ki-67 antigen), microvessel morphology, and survival. Of 84 cases analyzed, 61 cases (72.6%) displayed strong membrane and/or cytoplasmic expression of CAIX and were grouped as positive. Immunoreactivity tended to have a perinecrotic distribution and increased in parallel with the extent of necrosis (P < .001) and histologic grade (P < .001). A positive correlation was also noted with HIF-1alpha and VEGF expression (P < .001), proliferation rate (P = .010), microvessel density (P = .004), and microvessel caliber parameters (P = .014-.038). In univariate survival analysis, increased CAIX expression was associated with shortened survival in the entire cohort (P < .0001), along with VEGF (P = .0205) and HIF-1alpha levels (P = .0190). Multivariate analysis selected the interaction model of CAIX, with grade and age as the only parameters independently affecting survival. CAIX expression was also the only significant parameter for the survival of patients with grades II/III. We conclude that CAIX may be used as a prognostic indicator in diffuse astrocytomas to refine the information provided by grade. Given the role of CAIX in the acidification of tumor environment and its up-regulation by hypoxia, it is thought that CAIX expression may be linked to resistance of tumor cells to radiotherapy by allowing them to acclimatize to a hypoxic and acidic microenvironment.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0046-8177
pubmed:author
pubmed:issnType
Print
pubmed:volume
38
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
629-38
pubmed:dateRevised
2007-5-2
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Expression of hypoxia-related tissue factors in astrocytic gliomas. A multivariate survival study with emphasis upon carbonic anhydrase IX.
pubmed:affiliation
Department of Pathology, National and Kapodistrian University of Athens, GR 115 27 Athens, Greece. pkorkol@cc.uoa.gr
pubmed:publicationType
Journal Article