title: Identification of microRNAs in Nipple Discharge as Potential Diagnostic Biomarkers for Breast Cancer.
abstract: BACKGROUND
  Intraductal breast cancer is generally difficult to diagnose because of a lack of an efficient method for detection. The purpose of this study was to reveal and validate the differential expression of microRNAs (miRNAs) in nipple discharge from intraductal papilloma patients and identify miRNAs as novel potential biomarkers for primary breast cancer.
  
  
  METHODS
  Nipple discharge samples were collected from three intraductal carcinoma breast cancer patients and three intraductal papilloma patients. The initial screening of miRNA expression was performed with an Axon GenePix 4000B microarray scanner using a novel approach to label miRNAs. The expression levels of the miRNAs selected from the initial screening were further examined by quantitative real-time polymerase chain reaction (qRT-PCR) in 21 validation samples (8 carcinomas and 13 benign tumors). An independent t test was used to detect significant correlations between the miRNA expression levels and breast cancer.
  
  
  RESULTS
  Microarray profiling demonstrated that three miRNAs were markedly up-regulated and three miRNAs were down-regulated in the intraductal carcinoma breast cancer patients compared to the papilloma group. The qRT-PCR analysis further verified that four miRNAs (miR-4484, miR-K12-5-5p, miR-3646, and miR-4732-5p) might serve as potential tumor biomarkers for breast cancer detection.
  
  
  CONCLUSIONS
  The novel approach of using a microarray scanner is applicable for studying biomarkers in nipple discharge containing small amounts of miRNA. miRNAs could serve as potential tumor biomarkers that can assist in breast cancer screening. Up-regulation of miR-4484, miR-K12-5-5p, and miR-3646 in nipple discharge may be a predictor of malignant breast cancer.
authors.affiliation: Department of Breast Surgery, Qilu Hospital of Shandong University, Jinan, Shandong, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Zhang
authors.affiliation: Department of Breast Surgery, Qilu Hospital of Shandong University, Jinan, Shandong, China.
authors.forename: Song
authors.initials: S
authors.lastname: Zhao
authors.affiliation: Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY, USA.
authors.forename: Qing
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY, USA.
authors.forename: Hsin-Sheng
authors.initials: HS
authors.lastname: Yang
authors.affiliation: Department of Breast Surgery, Qilu Hospital of Shandong University, Jinan, Shandong, China. drjiangzhu@hotmail.com.
authors.forename: Jiang
authors.initials: J
authors.lastname: Zhu
authors.affiliation: Department of Breast Surgery, Qilu Hospital of Shandong University, Jinan, Shandong, China. marongw2000@163.com.
authors.forename: Rong
authors.initials: R
authors.lastname: Ma
mesh_terms: D014408:Biomarkers, Tumor / Q000235:genetics*; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism; D055088:Early Detection of Cancer; D005260:Female; D005500:Follow-Up Studies; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D009558:Nipples / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D010212:Papilloma / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism; D011379:Prognosis; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D014408:Biomarkers, Tumor; D035683:MicroRNAs