Hypoxia-inducible factor 1 alpha (HIF-1α) gene expression in human ovarian carcinoma

Hypoxia-inducible factor1alpha (HIF-1alpha)that regulates genes involved in response to hypoxia and promotes neo-angiogenesis, is a transcriptional factor for vascular endothelial cell growth factor (VEGF). The aim of this study was to examine the expression of HIF-1alpha and VEGF gene expressions and their relation to angiogenesis, clinicopathologic variables and survival in the patient with human ovarian carcinoma. We retrospectively analyzed HIF-1alpha and VEGF gene expression levels using reverse transcriptase polymerase chain reaction (RT-PCR) in 60 ovarian carcinomas. Intratumoral microvessel density (IMD) was assessed by immunostaining endothelial cells, using anti-CD 31 antibody in frozen sections. The relationships between the expression level of these genes, IMD and clnicopathologic variables were evaluated by Student's t-test and chi-square tests. Survival analysis was performed by Kaplan-Meier curves. HIF-1alpha or VEGF gene expression level was independent of age, clinical stage and histological subtype besides grade of tumor. There was no relationship between HIF-1alpha or VEGF gene expression level and IMD in all carcinomas (R = 0.118 and 0.224, respectively). In addition, a weak association between HIF-1alpha and VEGF gene expression level was observed (R = 0.300, P = 0,020). The association between VEGF gene expression and IMD was observed (R = 0.501, P = 0.016). However, no association between IMD and HIF-1alpha gene expression was observed. Further, both HIF-1alpha and VEGF gene expression levels had no effect on survival in the patient with ovarian carcinoma. These results suggest that VEGF upregulated by HIF-1alpha gene may be involved in angiogenesis of some type of ovarian carcinoma, but the expression levels of both genes have no effect on survival in the patients with ovarian carcinoma. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.