title: Frequent overexpression of PDK1 in primary nasopharyngeal carcinoma is associated with poor prognosis.
abstract: OBJECTIVE
  Pyruvate dehydrogenase kinase 1 (PDK1) is reported to be up-regulated and play multiple functions in several cancers. Herein, we investigated its roles in primary nasopharyngeal carcinoma.
  
  
  METHODS
  Expression of PDK1 protein was examined by immunohistochemical staining in 102 samples of primary nasopharyngeal carcinoma (pNPC) and 31 samples of chronic nasopharyngitis. The relationships of PDK1 expression levels with clinical features and prognosis in NPC patients were analyzed.
  
  
  RESULTS
  PDK1 protein expression was significantly greater in pNPC tissues than in the chronic nasopharyngitis tissues (P<0.01). In addition, overexpression of PDK1 was associated with advanced clinical stage (P<0.01), advanced N classification (P=0.024), and distant metastasis (P=0.048). Kaplan-Meier survival analysis demonstrated that patients with higher PDK1 expression had significantly shorter overall survival (P=0.006), disease-free survival (P=0.015), loco-regional relapse-free survival (P=0.008), and distant metastasis-free survival (P=0.017). Furthermore, multi-variate analysis showed that PDK1 expression was an independent prognostic factor in pNPC patients.
  
  
  CONCLUSIONS
  PDK1 is frequently upregulated in pNPC and may serve as a prognostic marker.
authors.affiliation: Department of Otolaryngology, Wenzhou Central Hospital, Wenzhou, China.
authors.forename: Guangzao
authors.initials: G
authors.lastname: Xiang
authors.affiliation: Department of Otolaryngology, The Third Affiliated Hospital of Wenzhou Medical University, Wenzhou, China.
authors.forename: Xianhui
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Otolaryngology, The Third Affiliated Hospital of Wenzhou Medical University, Wenzhou, China.
authors.forename: Longhe
authors.initials: L
authors.lastname: Cao
authors.affiliation: Department of Otolaryngology, The Third Affiliated Hospital of Wenzhou Medical University, Wenzhou, China.
authors.forename: Chuansai
authors.initials: C
authors.lastname: Zhu
authors.affiliation: Department of Otolaryngology, The Third Affiliated Hospital of Wenzhou Medical University, Wenzhou, China.
authors.forename: Zhijian
authors.initials: Z
authors.lastname: Dai
authors.affiliation: Department of Pathology, the Third Affiliated Hospital of Wenzhou Medical University, Wenzhou, China.
authors.forename: Shenhua
authors.initials: S
authors.lastname: Pan
authors.affiliation: Department of Otolaryngology, The Third Affiliated Hospital of Wenzhou Medical University, Wenzhou, China. Electronic address: lnns@163.com.
authors.forename: Sen
authors.initials: S
authors.lastname: Lin
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis*; D002277:Carcinoma; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000378:metabolism* / Q000401:mortality; D011379:Prognosis; D017346:Protein Serine-Threonine Kinases / Q000032:analysis / Q000096:biosynthesis*; D000081382:Pyruvate Dehydrogenase Acetyl-Transferring Kinase; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; C000631429:PDK1 protein, human; D000081382:Pyruvate Dehydrogenase Acetyl-Transferring Kinase; D017346:Protein Serine-Threonine Kinases
keywords: Nasopharyngeal carcinoma; Primary; Prognosis; Pyruvate dehydrogenase kinase 1