Targeted Overexpression of NDRG2 using Survivin Promoter Reduces Viability and Invasiveness of A549 Cell Line

Abstract

Background: Anti-tumor effects of N-myc Downstream Regulated Gene2 (NDRG2) have been demonstrated in many tumors. In the present study, NDRG2 was specifically overexpressed in lung cancer cell line using Survivin Promoter (Sur-P). Then, the effects of NDRG2 overexpression on viability, apoptosis, migration, and invasion of A549 cells were evaluated. Methods: Recombinant pAdenoVator-Sur-P-NDRG2-IRES-GFP plasmid harboring NDRG2 gene under transcriptional control of Sur-P and mock plasmid were constructed. A549 lung tumor cells and LX-2 cells (non-tumor cell line) were transfected with pAdenoVator-Sur-P-NDRG2-IRES-GFP, pAdenoVator-CMV-NDRG2-IRES-GFP, or mock plasmids. Tumor specificity of Sur-P was evaluated using fluorescent microscopy for GFP expression. The effects of NDRG2 overexpression on cell viability, apoptosis, and migration of A549 cells were measured using MTT, annexinV/7-AAD flow cytometry, and transwell migration assay, respectively. NDRG2 and matrix metalloproteinase-2 (MMP-2) expression were measured using real time-PCR. Results: pAdenoVator-Sur-P-NDRG2-IRES-GFP transfection resulted in a huge GFP expression in A549 cells, but not in LX-2 cells. The results of real time-PCR analysis also showed that pAdenoVator-Sur-P-NDRG2-IRES-GFP transfection led to an abundant NDRG2 expression in A549 cells. NDRG2 overexpression decreased A549 cell viability through increasing cell apoptosis. In addition, migration, invasion, and MMP-2 expression decreased following NDRG2 overexpression in A549 cells. Conclusion: The findings indicate that the targeted overexpression of NDRG2 using Sur-P can reduce the viability and invasiveness of A549 cells, suggesting possible benefits of this approach in lung cancer therapy.