Document Type : Original Article


1 Division of Medical Biotechnology, Department of Medical Laboratory Sciences, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran

2 Diagnostic Laboratory Sciences and Technologym Research Center, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran

3 Department of Clinical Sciences, School of Veterinary Medicine, Shiraz University, Shiraz, Iran


Background: A high number of human breast cancers overexpress the murine double minute (MDM2) gene which blocks the p53 protein which plays an important role in arresting the cell growth. The present study aimed to investigate the efficacy of siRNA specific MDM2 in knocking down MDM2 and its subsequent effects on p53 to exert antiproliferative effects on Michigan Cancer Foundation-7 (MCF-7) breast cancer cells.
Method: In this in vitro study, we used the specific siRNA of the MDM2 gene to knock down the expression of the MDM2 protein in the MCF-7 cell line. The expression of MDM2, BCL2-associated X (BAX), BH3 interacting-domain death agonist (BID), and B cell lymphoma 2 (BCL2) genes was evaluated using the real-time polymerase chain reaction (PCR) technique. The apoptosis level was also assessed using the flow cytometry technique by the Annexin V test.
Results: The results showed that the entry of MDM2 siRNA into MCF-7 cells significantly reduced the mRNA expression of MDM2 gene (P-value < 0.05). Besides, the expression of the antiapoptotic gene of BCL2 significantly decreased (P-value < 0.05) in transfected MCF-7 cells, while that of BAX and BID genes increased (P-value < 0.05).
Conclusion: Based on the results, MDM2 inhibition is conducive to prevent cancer metastasis by the induction of cancer cell apoptosis. Moreover, it can be considered in cancer therapy along with chemotherapy.


How to cite this article:

Kalantari T, Mohseni-Aghdam B, Nasri F, Tamaddon G, Kalantari M. The efficacy of siRNA specific MDM2 in the induction of apoptosis in MCF-7 breast cancer cell line. Middle East J Cancer. 2022;13(4):565-72. doi: 10.30476/mejc. 2021.89554. 1532.

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