Down-regulation of miR-199b-5p is correlated with poor prognosis for breast cancer patients

Biomed Pharmacother. 2016 Dec;84:1189-1193. doi: 10.1016/j.biopha.2016.10.006. Epub 2016 Oct 24.

Abstract

Objectives: The purpose of the present study was to evaluate the prognostic value of miR-199b-5p in breast cancer patients, as well as explore its effects on breast cancer cells.

Methods: The expression level of miR-199b-5p in breast cancer tissues and paired non-cancerous tissues were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Chi-square test was used to evaluate the relationship between miR-199b-5p expression and clinical parameters. Besides, overall survival analysis was carried out with Kaplan-Meier curve with log rank test, and the prognostic value of miR-199b-5p in breast cancer was evaluated by cox regression model. In addition, MTT and transwell assays in vitro were used to estimate the effects of miR-199b-5p on breast cancer cells.

Results: MiR-199b-5p was down-regulated in breast cancer tissues, compared with adjacent normal tissues (P<0.05). Moreover, its decreased level was significantly correlated with advanced TNM stage (P=0.008) and positive lymph node metastasis (P=0.013). Cell experiments suggested that miR-199b-5p could regulate proliferation and invasion of breast cancer cells. In addition, we found that breast cancer patients with low miR-199b-5p expression level had poorer overall survival than those with high level (log rank test, P=0.021). MiR-199b-5p was an independent prognostic factor for breast cancer patients (HR=2.318, 95%CI=1.086-4.949, P=0.030).

Conclusion: Down-regulated miR-199b-5p in breast cancer patients is associated with malignant clinical characteristics. MiR-199b-5p may be a potential prognostic biomarker for breast cancer.

Keywords: Breast cancer; MiR-199b-5p; Prognosis.

MeSH terms

  • Breast Neoplasms / genetics*
  • Breast Neoplasms / pathology
  • Cell Proliferation
  • Down-Regulation / genetics*
  • Female
  • Gene Expression Regulation, Neoplastic*
  • Humans
  • MCF-7 Cells
  • MicroRNAs / genetics*
  • MicroRNAs / metabolism
  • Middle Aged
  • Neoplasm Invasiveness
  • Prognosis
  • Proportional Hazards Models
  • Survival Analysis

Substances

  • MicroRNAs
  • mirn199 microRNA, human