Overexpression of miR-146a and TNF-a increase the risk of breast cancer

Overexpression of miR-146a and TNF-a increase the risk of breast cancer
Zahra Moein,^1,* Mahboobeh Nasiri,²
1. Department of Biology, Islamic Azad University, Arsanjan Branch, Arsanjan, Iran
2. Department of Biology, Islamic Azad University, Arsanjan Branch, Arsanjan, Iran
Introduction: The NF-kappa B (NF-κB) signaling pathway can help to explain the link between inflammation and cancer. MiR-146a influences the function of NF-κB and contributes to different aspects of tumorigenesis. Tumor necrosis factor-alpha (TNF-α) has been shown to promote tumor initiation, promotion, as well as invasion and metastasis as necessary tissue architecture for tumor development through activation of NF-κB. In this case control study, we evaluated the TNF-α and miR-146a mRNA expression pattern in breast cancer (BC) to shed light on some aspects of breast cancer in the molecular level.
Methods: Fifty-two women diagnosed with BC (44 DCIS; 8 LCIS) and 52 healthy women as controls were enrolled in the present study. The expression of the TNF-α and miR-146a genes was determined by reverse transcription quantitative-polymerase chain reaction (qRT-PCR). All cases were examined for the receptor of estrogen and progesterone using Allred scoring and immunohistochemistry for TP53. Hematoxylin-eosin staining was used to differentiate different types of BC.
Results: Patient women presented with increased TNF-α and miR-146a expression compared to controls (P < 0.0001). The expression of TNF-α among women above 50 years was significantly higher compared to controls, while the expression of the mRNA expression of miR-146a in women below 50 years was significantly higher than controls.
Conclusion: The data obtained from the present study demonstrated that upregulation of TNF-α and miR-146a expression may involve in tumor initiation and promotion by facilitating malignant cell transformation of breast cells through NF-κB activity.
Keywords: Breast cancer, miR-146a, TNF-α, NF-κB signaling pathway, Gene expression