Expression of Hypoxia-Inducible Factors in Different Stages of Pancreatic Tumor Progression

Background: Early diagnosis in pancreatic cancer is key for improving prognosis. Hypoxia plays a critical role in tumor progression. Thus, an evaluation of associations between pancreatic tumor progression and markers of hypoxia is needed. Methods: We assessed the expression of hypoxia-inducible factors (HIF-1 alpha and HIF-2 alpha) by immuno-histochemical staining from 29 subjects with the following: pancreatic intraepithelial neoplasia (PanIN), intraductal papillary mucinous neoplasm (IPMN), neuroendocrine tumor (NET), and pancreatic ductal adenocarcinoma (PDAC) and compared it to the expression in non-tumor samples. Results: Expression of HIF-1 alpha increased significantly from PanIN (3.01 +/- 0.17) to IPMN (7.63 +/- 0.18), NET (9.10 +/- 0.23) and PDAC samples (11.06 +/- 0.15, p < 0.0001). Similar findings were observed for HIF-2 alpha (p < 0.0001)}. A strong correlation between HIF-1 alpha and HIF-2 alpha expression was demonstrated (R2 = 0.8408, p < 0.0001). Conclusions: This data suggest that HIF-1 alpha and HIF-2 alpha may play a role in the progression from PanIN through PDAC. Further studies are necessary to confirm these findings and determine the effect of HIFs abrogation on tumor progression that can lead to novel therapies.