Expression And Its Clinical Significance Of HIF-2α,GLUT-1 And OPN In Nasopharyngeal Carcinoma

OBJECTIVE To investigate the expression of HIF-2α, GLUT-1 and OPN protein in nasopharyngeal carcinoma(NPC) and its correlation with clinic biological behavior and respone to radiotherapy, and to explore the role of HIF-2α, GLUT-1 and OPN in diagnosing, staging, treating and prognosis evaluating of NPC.METHODS Immunohistochemical technology was applied to detect expression of HIF-2α, GLUT-1 and OPN protein in 51 NPC tissue samples and 20 tissue samples of chronic nasopharyngitis. The dynamic variation in expression level of HIF-2α, GLUT-1 and OPN protein in pre-radiotherapy (pre-RT), during-radiotherapy (during-RT), and post-radiotherapy (post-RT) were detected in biopsies from 29 NPC patients. The level of serum OPN was detected with ELISA in 30 cases of NPC and 20 healthy controls.RESULTS The positive expression rate of HIF-2α, GLUT-1 and OPN were 62.7%,49%, and 52.9% in NPC tissue and 20%, 10% and 10% in chronic nasopharyngitis tissue, respectively, and there were significant difference in the expression of HIF-2α, GLUT-1 and OPN between NPC and chronic nasopharyngitis tissue (P<0.05). The positive expression rate of HIF-2αprotein was correlated with T classification, clinical stage as well as cervical lymph node metastases and the positive expression rate of GLUT-1 protein was significantly correlated to clinical stage and cervical lymph node metastases(P<0.05), but the positive expression of HIF-2αand GLUT-1 were not correlated with gender and age (P>0.05). The positive expression rate of OPN protein was not significantly correlated with gender, age, T classification, clinical stage, and cervical lymph node metastases (P>0.05). The expression of HIF-2αprotein was positively correlated with GLUT-1 protein expression in NPC tissue (P<0.01), but no correlation were found between the expression of OPN protein and the expression of HIF-2αand GLUT-1 (P>0.05). Among 29 patients which had been examined dynamically, the expression of HIF-2α, GLUT-1 and OPN protein significantly decreased in during-RT compared to those of pre-RT (P<0.05). The level of serum OPN in patients with NPC was 161.02±44.80ng/ml, which was significantly higher than that in healthy controls (58.89±24.65ng/ml) (P<0.01). The level of serum OPN was correlated with clinical stage and cervical lymph node metastases in patients with NPC (P<0.05), but was not correlated with gender, age and T classification (P>0.05). There were no correlation between the level of serum OPN and the expression HIF-2α, GLUT-1 and OPN protein (P>0.05) in NPC tissue.CONCLUSIONS The increased expression of HIF-2α, GLUT-1 and OPN protein may be play a significant role in occurrence and development of NPC. Combined detection of HIF-2αand GLUT-1 protein expression is of great value for staging, judging outcome and evaluating the prognosis of NPC. Detection of the level of serum OPN may be serve as a adjunctive marker for diagnosing, staging and prognosis evaluating of NPC.