• Gene Expression of Long Non-Coding RNAs; EGFR-AS1, EGFR-208, and EGFR-209 in Triple-negative breast cancer
  • Ali Zekri,1,* Shahrzad Fakhri,2
    1. Department of medical genetics, school of medicine, Iran university of medical sciences, Tehran, Iran, and Physiology research center, Iran university of medical sciences, Tehran, Iran
    2. Medical genomics research center, Tehran medical science branch, Islamic Azad University, Tehran, Iran


  • Introduction: Triple-negative breast cancer (TNBC) is a type of malignant breast cancers which have a poor prognosis and a high risk of mortality. Remarkably, there is growing evidence demonstrating that lncRNAs play an important role in regulating cancer-related mechanisms and metastasis. Then, they can be used as biomarkers for monitoring the disease. Among different lncRNAs, epidermal growth factor receptor-antisense RNA 1 (EGFR-AS1) has been under great attention for its abnormal expression in cancers with epithelial origin. Consequently, here, we aimed to investigate the expression of EGFR-AS1, and its close family of lncRNAs means EGFR-208, and EGFR-209 in different subtypes of breast tumors compared to adjacent tissues.
  • Methods: Breast tumor specimens and adjacent normal tissue were obtained from the bariatric surgery center of Rasoul Akram Hospital, Tehran, Iran. Total RNA was extracted using the Tripure isolation reagent kit, according to the manufacturer's protocol. RNA purity was measured by evaluating the ratio of absorbance at 260 nm to 280 nm by a nanodroplet and its integrity using agarose gel and staining with ethidium bromide. complementary DNA (cDNA) synthesis was performed on 1000 ng of RNA using a cDNA synthesis kit, according to the manufacturer's protocol. Real-time PCR was conducted to investigate the mRNA expression of the above-mentioned genes in all participants. Quantitative Real-time PCR was performed using SYBR Green and LightCycler 96 real-time PCR system , based on the manufacturer’s protocol. Fold changes of lncRNAs gene expression of case samples relative to the controls were calculated by the 2-ΔCt method. B2M was used as the internal gene for the study of lncRNAs. Thus, the ΔCt value of each sample was normalized to the value of B2M.
  • Results: The gene expression of EGFR-AS1, EGFR-208, and EGFR-209 were lower in all three groups compared to adjacent tissues. There was a significant decrease (P<0.05) in the gene expression of EGFR-AS1 and EGFR-209 in the triple-positive subtype compared to adjacent tissues. There was also a significant decrease (P<0.001) in the gene expression of EGFR-AS1 in the triple-negative group compared to the triple-positive group.
  • Conclusion: This study indicates the likely diagnostic value of EGFR-AS1, EGFR-208, and EGFR-209 for TNBC and provides new insights into the control strategies for TNBC. However, further studies are needed to validate this concept.
  • Keywords: Long non-coding RNAs (lncRNAs), Breast cancer, Triple-negative breast cancer (TNBC), EGFR