Expression of hypoxia-inducible factor-1 alpha and associated proteins in pancreatic ductal adenocarcinoma and their impact on prognosis

Abstract

The aim of this study was to assess the significance of expression of hypoxia-inducible factor-1α (HIF-1α) and associated proteins in pancreatic ductal adenocarcinoma (PDA) and their impact on prognosis. Expression of HIF-1α, vascular endothelial growth factor (VEGF), glucose transporter-1 (Glut-1), survivin, CD34 and Ki-67 and apoptotic cells was demonstrated by immunohistochemistry or TUNEL in 58 PDAs and 20 normal pancreatic tissue samples. Our results show positivity of HIF-1α, VEGF, Glut-1 and survivin in 70.7%, 77.6%, 67.2% and 84.5% of the patients with PDA, respectively, which is significantly higher than in the normal counterparts. Expression of HIF-1α correlated positively with VEGF and Glut-1 expression but not with survivin. Strong HIF-1α expression associated with decreased apoptotic index and increased intratumoral microvessel density. Higher HIF-1α, VEGF and Glut-1 expression significantly associated with advanced tumor stage and lymph node metastasis. Patients with high HIF-1α, VEGF and Glut-1 expressing tumors had a poorer overall survival. Furthermore, Cox regression analysis showed that HIF-1α is a prognostic marker of borderline significance while VEGF was important in predicting poor outcome. These results suggest that over-expression of HIF-1α may play an important role in cancer progression through upregulation of VEGF and Glut-1 in PDA patients. HIF-1α and VEGF are potential candidates for predicting survival.