Expression analysis of selected miR-206 targets from the transforming growth factor-β signaling pathway in breast

Mahnaz Seifi-Alan1, Ali Dianatpour1, Lobat Geranpayeh2

  • 1Department of Medical Genetics, Shahid Beheshti University of Medical Sciences, Velenjak, Tehran, Iran.

Insights

MicroRNA-206 (miR-206) is downregulated in Estrogen Receptor-positive breast cancer, correlating with advanced disease stages. Its target genes, SMAD2 and LEF1, are linked to body mass index, highlighting TGF-β pathway dysregulation in breast cancer.

Area of Science:

  • Oncology
  • Molecular Biology
  • Genetics

Background:

  • Breast cancer exhibits molecular heterogeneity, with dysregulated transforming growth factor-β (TGF-β) signaling pathways.
  • MicroRNAs (miRNAs) play a crucial role in breast cancer pathogenesis.

Purpose of the Study:

  • To identify miR-206 target genes functionally linked to the TGF-β signaling pathway.
  • To assess the expression of selected genes (LEF1, Smad2, Snail2) and miR-206 in breast cancer tissues and correlate them with clinicopathological features.

Main Methods:

  • Computerized search for miR-206 target genes involved in TGF-β signaling.
  • Quantitative assessment of miR-206, LEF1, Smad2, and Snail2 expression in 65 breast cancer samples and adjacent non-cancerous tissues (ANCTs).
  • Correlation analysis between gene/miRNA expression and patient clinicopathological characteristics (ER status, BMI, TNM stage, mitotic rate, lymph node involvement, HER2 status).

Main Results:

  • miR-206 was significantly downregulated in Estrogen Receptor (ER)-positive breast cancer samples compared to ANCTs.
  • High expression of SMAD2 correlated with HER2 status.
  • Low miR-206 expression was associated with advanced TNM stage, higher mitotic rate, and lymph node involvement.
  • SMAD2 and LEF1 expression showed significant association with body mass index.

Conclusions:

  • Dysregulation of TGF-β signaling is implicated in breast cancer pathogenesis.
  • miR-206 and its target genes represent potential biomarkers for breast cancer detection and therapeutic targets.
  • Further investigation into miRNAs and messenger RNA coding genes within the TGF-β pathway is warranted.

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