title: Differential expression levels of plasma-derived miR-146b and miR-155 in papillary thyroid cancer.
abstract: BACKGROUND
  Specific circulating microRNAs (miRNAs) in each organ may contribute to the diagnosis and prognosis in some cancers. miRNA from papillary thyroid cancer (PTC) may be released into the bloodstream. This study was performed to detect miRNAs in the plasma and estimate their diagnostic usefulness for discriminating between benign and malignant lesions.
  
  
  METHODS
  Patients who underwent thyroidectomy for benign thyroid nodules or PTC were enrolled in this study. The patients were divided into three groups: benign, PTC without lymph node metastasis (LNM), and PTC with LNM. The levels of miR-146b, miR-221, miR-222, and miR-155miRNA expression in blood samples before surgery were evaluated.
  
  
  RESULTS
  Of 89 patients enrolled in this study, 19 and 70 had benign lesions (21.3%) and PTC (78.7%), respectively. The mean levels of miR-146b and miR-155 expression were higher in the PTC group than the benign group. For discrimination between benign and PTC lesions, the area under the ROC curve (AUC) for miR-146b was 0.649 with 61.4% sensitivity and 57.9% specificity. The AUC for miR-155 was 0.695 with 74.3% sensitivity and 63.2% specificity (P<0.05). The levels of miR-146b, miR-221, and miR-222 were slightly higher in the N1 group than the N0 group. The levels of miR-146b, miR-155, and miR-222 increased in proportion to tumor size.
  
  
  CONCLUSIONS
  miR-146b and miR-155 helped to discriminate between benign and malignant lesions. Circulating miRNA is likely a useful alternate serological marker for PTC. This preliminary study suggested that circulating miRNAs may be useful as follow-up tools as well as diagnostic tools.
authors.affiliation: Department of Otolaryngology, Asan Medical Center, University of Ulsan, College of Medicine, Seoul 138-736, Republic of Korea.
authors.forename: Yoon Se
authors.initials: YS
authors.lastname: Lee
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Ilsan Hospital, Dongguk University, Goyang, Gyeonggi 410-773, Republic of Korea.
authors.forename: Yun Sung
authors.initials: YS
authors.lastname: Lim
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Pusan National University School of Medicine and Medical Research Institute, Busan 602-739, Republic of Korea.
authors.forename: Jin-Choon
authors.initials: JC
authors.lastname: Lee
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Pusan National University School of Medicine and Medical Research Institute, Busan 602-739, Republic of Korea.
authors.forename: Soo-Geun
authors.initials: SG
authors.lastname: Wang
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Pusan National University School of Medicine and Medical Research Institute, Busan 602-739, Republic of Korea.
authors.forename: Hee-Young
authors.initials: HY
authors.lastname: Park
authors.affiliation: Department of Laboratory Medicine, Pusan National University School of Medicine and Medical Research Institute, Busan 602-739, Republic of Korea.
authors.forename: Shine Young
authors.initials: SY
authors.lastname: Kim
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Pusan National University School of Medicine and Medical Research Institute, Busan 602-739, Republic of Korea. Electronic address: voicelee@pusan.ac.kr.
authors.forename: Byung-Joo
authors.initials: BJ
authors.lastname: Lee
mesh_terms: D014408:Biomarkers, Tumor / Q000097:blood* / Q000235:genetics; D006801:Humans; D035683:MicroRNAs / Q000097:blood* / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D013964:Thyroid Neoplasms / Q000097:blood*
chemical_list: D014408:Biomarkers, Tumor; C542542:MIRN146 microRNA, human; C524942:MIRN155 microRNA, human; D035683:MicroRNAs
keywords: MicroRNA; Papillary thyroid cancer; Plasma; Tumor size