title: The expression and significance of five types of miRNAs in breast cancer.
abstract: BACKGROUND
  This study aimed to investigate the expression and significance of 5 types of miRNAs in breast cancer to provide a theoretical and practical foundation for using these miRNAs in the diagnosis and treatment of breast cancer, thereby improving medical services.
  
  
  METHODS
  Stem-loop real-time RT-PCR was used to detect the expression levels of miR-145, miR-21, miR-10b, miR-125a, and miR-206 in 35 cases of breast cancer and adjacent normal breast tissues, and to analyze the relationship of miRNAs expression with clinicopathological features of breast cancer. The expression levels of estrogen receptor (ER) and progesterone receptor (PR) were examined by immunohistochemistry. Fluorescence in situ hybridization was used for the detection of HER-2 and TOP 2A.
  
  
  RESULTS
  The expression levels of miR-145, miR-125a, and miR-206 in breast cancer were lower than those in adjacent normal tissues. MiR-145 was negatively correlated with tumor size, lymph node metastasis, ER, HER-2, and TOP 2A (P<0.05), regardless of age, menstruation, and PR. MiR-125a was correlated with negative node status, negative HER-2 status (P<0.05), whereas tumor size, age, menstruation, ER, and PR were independent factors. MiR-206 expression was correlated with negative ER status, negative PR status, and negative HER-2 status (P<0.05), regardless of age, menstruation, lymph node metastasis, and TOP 2A. MiR-21 and miR-10b expression in breast cancer tissues was significantly higher than that in adjacent tissues (P<0.05). MiR-21 in post-menstrual patients with lymph node metastasis was highly expressed (P<0.05), and had no correlations with tumor size, ER, PR, and TOP 2A expression. MiR-10b expression was positively correlated with breast cancer tumor size, lymph node metastasis, and TOP 2A status (P<0.05), but had no correlations with age, menstruation, ER, PR, and HER-2.
  
  
  CONCLUSIONS
  MiR-145, miR-21, miR-10b, miR-125a, and miR-206 may play important roles in breast cancer development and invasion.
authors.affiliation: Department of Hepatobiliary Surgery, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China (mainland).
authors.forename: Weili
authors.initials: W
authors.lastname: Min
authors.affiliation: Department of Oncology, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China (mainland).
authors.forename: Baofeng
authors.initials: B
authors.lastname: Wang
authors.affiliation: Department of Oncology, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China (mainland).
authors.forename: Jie
authors.initials: J
authors.lastname: Li
authors.affiliation: Health Science Center, Xi'an Jiaotong University School of Medicine, Xi'an, China (mainland).
authors.forename: Jia
authors.initials: J
authors.lastname: Han
authors.affiliation: Department of Oncology, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China (mainland).
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Department of Oncology, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China (mainland).
authors.forename: Wenjun
authors.initials: W
authors.lastname: Su
authors.affiliation: Department of Oncology, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China (mainland).
authors.forename: Zhijun
authors.initials: Z
authors.lastname: Dai
authors.affiliation: Department of Oncology, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China (mainland).
authors.forename: Xijing
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Oncology, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China (mainland).
authors.forename: Qingyong
authors.initials: Q
authors.lastname: Ma
mesh_terms: D000328:Adult; D000951:Antigens, Neoplasm / Q000378:metabolism; D001943:Breast Neoplasms / Q000235:genetics* / Q000473:pathology; D004250:DNA Topoisomerases, Type II / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D008875:Middle Aged; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism
chemical_list: D000951:Antigens, Neoplasm; D004250:DNA Topoisomerases, Type II; D004268:DNA-Binding Proteins; D035683:MicroRNAs; D018719:Erb-b2 Receptor Tyrosine Kinases