The expression level of miR-21, a target of the PTEN gene receptor in the PI3K signaling pathway, in clinical samples of triple negative breast cancer

Abstract

Background and Aim: Triple negative breast cancer (TNBC) is an aggressive form of breast cancer, necessitating effective treatment methods. This study aimed to assess the expression level of miR-21, a target of the Phosphatase and tensin homolog (PTEN) gene receptor in the PI3K signaling pathway, in clinical samples of TNBC. Methods: Fifteen TNBC tumor samples and 15 adjacent normal tissue samples were obtained from the tumor bank of Imam Khomeini Hospital in Tehran, Iran. RNA extraction, cDNA synthesis, and Quantitative Real-Time PCR (qRT-PCR) analysis were conducted. Relative expression of PTEN and miR-21 was analyzed using REST 2009® software, with gene expression also evaluated using the UALCAN database. Additionally, ROC curve analysis was performed to assess the diagnostic value of miR-21 in TNBC. Results: qRT-PCR analysis revealed a significant decrease in PTEN expression in most clinical samples (13 samples) by 4.6-fold, and a decrease in miR-21 target expression by 6.8-fold in 10 samples and 8.9-fold in 5 samples compared to normal tissue. These findings were supported by results from the UALCAN database. Furthermore, ROC curve analysis demonstrated the diagnostic potential of miR-21 in TNBC, with an area under the curve of 0.742. Conclusion: The study suggests that miR-21 could serve as a promising candidate for inhibiting PTEN gene expression, potentially aiding in targeted treatment for TNBC. However, further research in this area is recommended.

Keywords

• triple-negative breast cancer
• mir-21
• pten