Document Type: Original Research


1 Diagnostic Laboratory Sciences and Technology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran

2 Bacteriology and Virology Department, Shiraz University of Medical Sciences, Shiraz, Iran

3 Ionizing and Nonionizing Radiation Protection Research Center, Shiraz University of Medical Sciences, Shiraz, Iran

4 Department of Radiotherapy and Oncology, Shiraz University of Medical Sciences, Shiraz, Iran


Background: Radiation therapy is among the most conventional cancer therapeutic modalities with effective local tumor control. However, due to the development of radio-resistance, tumor recurrence and metastasis often occur following radiation therapy. In recent years, combination of radiotherapy and gene therapy has been suggested to overcome this problem. The aim of the current study was to explore the potential synergistic effects of N-Myc Downstream-Regulated Gene 2 (NDRG2) overexpression, a newly identified candidate tumor suppressor gene, with radiotherapy against proliferation of prostate LNCaP cell line.Materials and Methods: In this study, LNCaP cells were exposed to X-ray radiation in the presence or absence of NDRG2 overexpression using plasmid PSES- pAdenoVator-PSA-NDRG2-IRES-GFP. The effects of NDRG2 overexpression, X-ray radiation or combination of both on the cell proliferation and apoptosis of LNCaP cells were then analyzed using MTT assay and flow cytometery, respectively.Results: Results of MTT assay showed that NDRG2 overexpression and X-ray radiation had a synergistic effect against proliferation of LNCaP cells. Moreover, NDRG2 overexpression increased apoptotic effect of X-ray radiation in LNCaP cells synergistically.Conclusion: Our findings suggested that NDRG2 overexpression in combination with radiotherapy may be an effective therapeutic option against prostate cancer.


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