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Modeling Breast Cancer in Human Breast Tissue using a Microphysiological System
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Modeling Breast Cancer in Human Breast Tissue using a Microphysiological System

Published on: April 23, 2021

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miR-34a expression in human breast cancer is associated with drug resistance

Zhi-Hua Li1, Xueling Weng2, Qiu-Yun Xiong1

  • 1Department of Breast Surgery, The Third Hospital of Nanchang City, Key Laboratory of Breast Diseases, Nanchang, Jiangxi 330009, P.R. China.

Oncotarget
|January 2, 2018
PubMed

Insights

MicroRNA-34a (miR-34a) down-regulation correlates with breast cancer multi-drug resistance (MDR). Restoring miR-34a expression can reverse MDR and improve patient prognosis by targeting BCL-2, CCND1, and NOTCH1.

Area of Science:

  • Oncology
  • Molecular Biology
  • Genetics

Background:

  • MicroRNA-34a (miR-34a) is frequently downregulated in breast cancer.
  • This downregulation may be linked to multi-drug resistance (MDR) in breast cancer.
  • Understanding miR-34a's role is crucial for developing new therapeutic strategies.

Purpose of the Study:

  • To investigate the correlation between miR-34a expression and breast cancer MDR.
  • To analyze the prognostic value of miR-34a in breast cancer patients.
  • To identify the molecular targets of miR-34a involved in drug resistance.

Main Methods:

  • Cell-based experiments using multi-drug resistant MCF-7 cells and their parental counterparts.
  • Analysis of miR-34a expression in 113 breast cancer tissue samples.
  • Quantitative assessment of mRNA and protein levels for target genes (BCL-2, CCND1, NOTCH1, P53, TOP-2a, HER-2).

Main Results:

  • miR-34a expression was significantly lower in MDR-MCF-7 cells compared to parental cells.
  • Low miR-34a expression in patients correlated with poorer overall survival (OS) and disease-free survival (DFS).
  • miR-34a mimics partially reversed MDR and reduced BCL-2, CCND1, and NOTCH1 expression at mRNA and protein levels.

Conclusions:

  • miR-34a acts as a potential biomarker for breast cancer MDR and prognosis.
  • miR-34a may regulate drug resistance by targeting BCL-2, CCND1, and NOTCH1 in breast cancer.
  • Further research into miR-34a could lead to novel therapeutic interventions for drug-resistant breast cancer.
Keywords:
breast cancerdrug resistancemiR-34aprognosis

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