Expression of HIF-1alpha and iNOS in astrocytic gliomas: a clinicopathological study.
BACKGROUND
Hypoxia-inducible-factor-1 (HIF-1) is present at high levels in human tumors and plays a crucial role in tumor promotion by up-regulating several target genes. HIF-1 stimulates the production of NO through the induction of inducible NO synthase (iNOS).


METHODS
Sixty-three human astrocytic gliomas were analyzed by immunohistochemistry for HIF-1alpha and iNOS using formalin-fixed paraffin-embedded material. In 39 cases, the results of immunohistochemistry were correlated with the clinical outcomes.


RESULTS
HIF-1alpha was detected only in astrocytic gliomas grades III and IV, both in the nucleus and in the cytoplasm. The iNOS expression was increased in astrocytic gliomas grades I, II and III and was statistically significantly decreased in astrocytic gliomas grade IV. iNOS was localized round the capillary vessels as well. Statistical analysis showed that the HIF-1alpha and iNOS expressions did not correlate with patient survival.


CONCLUSIONS
We believe that HIF-1alpha and iNOS expressions merit further investigations in order to understand the biology of astrocytic gliomas. More data are needed from prospective studies.
Giannopoulou
E
E
Laboratory of Clinical Oncology, University of Patras Medical School, 26500, Rion, Greece.
Ravazoula
P
P
Kalofonos
H
H
Makatsoris
Th
T
Kardamakis
D
D
D000328:Adult; D000368:Aged; D001254:Astrocytoma / Q000201:enzymology* / Q000378:metabolism* / Q000473:pathology; D014408:Biomarkers, Tumor / Q000032:analysis*; D004790:Enzyme Induction; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000235:genetics / Q000378:metabolism*; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D052247:Nitric Oxide Synthase Type II / Q000096:biosynthesis* / Q000235:genetics; D012189:Retrospective Studies
D014408:Biomarkers, Tumor; C497442:HIF1A protein, human; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D052247:Nitric Oxide Synthase Type II