title: Predictive value of miR-9 as a potential biomarker for nasopharyngeal carcinoma metastasis.
abstract: BACKGROUND
  Nasopharyngeal carcinoma (NPC) has a distinctive geographic distribution and is characterised by its strong tendency of metastasis. We aimed to examine the microRNA (miRNA) expression profiles in plasma samples of NPC patients to explore their clinical significance in disease development and progression.
  
  
  METHODS
  This study was divided into four steps: (1) confirmation of differentially expressed miRNAs using microarray analysis and quantitative PCR validation; (2) comparison of plasma miR-9 levels during NPC progression; (3) evaluation of the predictive performance of plasma miR-9 as a biomarker for NPC metastasis; and (4) comparison of plasma miR-9 levels between pre- and post-treatment samples.
  
  
  RESULTS
  Plasma microarray profiling identified 33 differentially expressed miRNAs between NPC patients and healthy volunteers. The significantly declined level of miR-9 in NPC patients was confirmed through two-stage validation. The low level of plasma miR-9 was significantly correlated with worse lymphatic invasion and advanced TNM stage. The plasma miR-9 could distinguish locoregional from metastatic NPC cases with a high sensitivity and specificity. Furthermore, the plasma miR-9 level was significantly elevated in post-treatment plasma compared with those pre-treatment samples.
  
  
  CONCLUSIONS
  Our study reports that plasma miR-9 may serve as a useful biomarker to predict NPC metastasis and to monitor tumour dynamics.
authors: Department of Otolaryngology-Head and Neck Surgery, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
authors: J
authors: J
authors: Lu
authors: Department of Otolaryngology-Head and Neck Surgery, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
authors: X
authors: X
authors: Xu
authors: Department of Otolaryngology-Head and Neck Surgery, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
authors: X
authors: X
authors: Liu
authors: Department of Neurology, The Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China.
authors: Y
authors: Y
authors: Peng
authors: School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou 510515, China.
authors: B
authors: B
authors: Zhang
authors: Department of Otolaryngology-Head and Neck Surgery, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
authors: L
authors: L
authors: Wang
authors: Department of Otolaryngology-Head and Neck Surgery, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
authors: H
authors: H
authors: Luo
authors: Department of Otolaryngology-Head and Neck Surgery, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
authors: X
authors: X
authors: Peng
authors: Department of Otolaryngology-Head and Neck Surgery, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
authors: G
authors: G
authors: Li
authors: Department of Otolaryngology-Head and Neck Surgery, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
authors: W
authors: W
authors: Tian
authors: 1] Stanley Ho Center for Emerging Infectious Diseases, School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China [2] Li Ka Shing Institute of Health Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China.
authors: M
authors: M
authors: He
authors: Department of Otolaryngology-Head and Neck Surgery, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
authors: X
authors: X
authors: Li
mesh_terms: D000328:Adult; D014408:Biomarkers, Tumor / Q000097:blood / Q000235:genetics*; D002277:Carcinoma; D018450:Disease Progression; D005260:Female; D020869:Gene Expression Profiling / Q000379:methods; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D035683:MicroRNAs / Q000097:blood* / Q000235:genetics; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000097:blood / Q000235:genetics* / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor; C541874:MIRN92 microRNA, human; D035683:MicroRNAs