Coexpression of hypoxia-inducible factor-1α and glucose transporter-1 is associated with poor prognosis in oral squamous cell carcinoma patients

Aims: To study whether coexpression of the two hypoxia-related proteins hypoxia-inducible factor (HIF)-1 alpha and glucose transporter (GLUT)-1 has prognostic relevance in oral squamous cell carcinomas (OSCCs). Methods and results: Eighty-two OSCC samples were analysed for expression levels of HIF-1 alpha and GLUT-1 by immunohistochemistry. Protein expression was assessed with an immunoreactive score system, and the correlations between gene expression and both clinical and pathohistological parameters were examined. Overexpression of either GLUT-1 or HIF-1 alpha was associated with poor disease-specific survival in OSCC patients. Multivariate Cox proportional-hazards regression analysis revealed that increased expression of HIF-1 alpha was significantly associated with disease-specific survival (relative risk = 3.24, P = 0.024), as compared with the group with a low level of expression. Coexpression of HIF-1 alpha and GLUT-1 was additively and significantly associated with adverse prognoses in patients with OSCC. Patients whose tumours had increased levels of expression of both HIF-1 alpha and GLUT-1 were found to have a 5.13-fold increased risk of tumour-related death (P = 0.017). Conclusions: Coexpression of high levels of HIF-1 alpha and GLUT-1 is significantly correlated with prognosis in OSCC patients, suggesting that the coexpression of these proteins can be used as both an early diagnostic and independent prognostic marker.