Micro RNA 34a and Let-7a Expression in Human Breast Cancers is Associated with Apoptotic Expression Genes

Asian Pac J Cancer Prev. 2016;17(4):1887-90. doi: 10.7314/apjcp.2016.17.4.1887.

Abstract

Breast cancer is the most common cause of cancer-related death among women in the whole world. MiR- 34a and let-7a are well known tumor suppressors that participate in the regulation of apoptosis, invasion and other cellular functions. In this study, expression of miR-34a, let-7a and apoptosis pathway genes such as Bcl-2, Caspase-3 and P53 were evaluated using quantitative real-time PCR in 45 paired samples of normal margin and tumor tissue collected from breast cancer patient at advanced stage (3-4). MiR-34a, let-7a, caspase-3 and P53 expression are reduced and Bcl-2 expression is increased within tumoral tissues in comparison with normal margin tissues. P53 expression directly or indirectly was correlated with miR-34a, let-7a, Bcl-2 and caspase-3 expression. In This study we found that MiR-34a and let-7a expression are reduced in the tumoral tissues. Down- regulation of these two molecules correlated with expression of genes associated with apoptosis. These results suggest that due to the correlation of miR-34a and let-7a with apoptotic and anti-apoptotic pathways these molecules could participate as regulators in advanced clinical stages of breast cancer and should be considered as markers for diagnosis, prognostic assessment and targeted therapy.

MeSH terms

  • Apoptosis
  • Apoptosis Regulatory Proteins / genetics*
  • Biomarkers, Tumor / genetics*
  • Breast Neoplasms / genetics*
  • Breast Neoplasms / pathology*
  • Female
  • Gene Expression Regulation, Neoplastic
  • Humans
  • MicroRNAs / genetics*
  • Neoplasm Staging
  • Prognosis
  • Real-Time Polymerase Chain Reaction

Substances

  • Apoptosis Regulatory Proteins
  • Biomarkers, Tumor
  • MIRN34 microRNA, human
  • MicroRNAs
  • mirnlet7 microRNA, human