title: Relative quantitative expression of hypoxia-inducible factor-1α, -2α and -3α, and vascular endothelial growth factor A in laryngeal carcinoma.
abstract: The aim of the present study was to determine the relative quantitative expression of hypoxia-inducible factor (HIF)-1α, -2α and -3α, and VEGF-A in laryngeal carcinoma. A total of 63 patients with carcinoma of the larynx were enrolled in the study. Total RNA was isolated from fresh, frozen normal and tumor tissues of each patient, and quantitative polymerase chain reaction was performed. HIF-1α was upregulated in the majority of patients (44 patients; 69.84%). By contrast, only 7 (11.11%) patients from the whole group displayed HIF-2α overexpression, while the HIF-3α isoform was silenced in the majority of patients (48 patients, 76.19%). A small group of 5 (7.94%) patients exhibited significant overexpression of the HIF-3α isoform. VEGF-A expression was significantly higher (P<0.05) in patients with upregulated HIF-1α (2.72±1.41 RQ) compared with patients without upregulated HIF-1α (1.86±1.46 RQ). There was a moderate positive correlation between mRNA expression levels of HIF-1α and VEGF-A (rs=0.392; P<0.005). To the best of our knowledge, this study is first to report quantitative data with regard to the expression of all three HIF isoforms in malignant neoplasms. The findings suggest the existence of specific phenotypes of HIF expression in laryngeal carcinoma, where the HIF switch is absent.
authors.affiliation: Department of Ear, Nose and Throat, Medical University of Sofia, Sofia 1680, Bulgaria.
authors.forename: Todor Miroslavov
authors.initials: TM
authors.lastname: Popov
authors.affiliation: Department of Medical Chemistry and Biochemistry and Molecular Medicine Center, Medical University of Sofia, Sofia 1680, Bulgaria.
authors.forename: Teodora
authors.initials: T
authors.lastname: Goranova
authors.affiliation: Department of Medical Chemistry and Biochemistry and Molecular Medicine Center, Medical University of Sofia, Sofia 1680, Bulgaria.
authors.forename: Gergana
authors.initials: G
authors.lastname: Stancheva
authors.affiliation: Department of Medical Chemistry and Biochemistry and Molecular Medicine Center, Medical University of Sofia, Sofia 1680, Bulgaria.
authors.forename: Radka
authors.initials: R
authors.lastname: Kaneva
authors.affiliation: Department of Pathology, Medical University of Sofia, Sofia 1680, Bulgaria.
authors.forename: Tihomir
authors.initials: T
authors.lastname: Dikov
authors.affiliation: Department of Ear, Nose and Throat, Medical University of Sofia, Sofia 1680, Bulgaria.
authors.forename: Ivan
authors.initials: I
authors.lastname: Chalakov
authors.affiliation: Department of Ear, Nose and Throat, Medical University of Sofia, Sofia 1680, Bulgaria.
authors.forename: Julian
authors.initials: J
authors.lastname: Rangachev
authors.affiliation: Department of Ear, Nose and Throat, Medical University of Sofia, Sofia 1680, Bulgaria.
authors.forename: Dimitar
authors.initials: D
authors.lastname: Konov
authors.affiliation: Department of Ear, Nose and Throat, Medical University of Sofia, Sofia 1680, Bulgaria.
authors.forename: Spiridon
authors.initials: S
authors.lastname: Todorov
authors.affiliation: Department of Ear, Nose and Throat, Medical University of Sofia, Sofia 1680, Bulgaria.
authors.forename: Orlin
authors.initials: O
authors.lastname: Stoyanov
authors.affiliation: Department of Medical Chemistry and Biochemistry and Molecular Medicine Center, Medical University of Sofia, Sofia 1680, Bulgaria.
authors.forename: Vanio
authors.initials: V
authors.lastname: Mitev
keywords: hypoxia-inducible factor-1α; hypoxia-inducible factor-2α; hypoxia-inducible factor-3α; laryngeal carcinoma; vascular endothelial growth factor A