Combinatorial Control of Transgene Expression by Hypoxia-Responsive Promoter and MicroRNA Regulation for Neural Stem Cell-Based Cancer Therapy
Figure 3
Selection of the optimal hypoxia-responsive promoter and normoxia-specific miRNA in NSCs. (a) Luciferase assays showing promoter activities. CXCR4 promoter, VEGF promoter, optHRP, and EF1α promoter were cloned into the pGL4.11 promoterless luciferase reporter plasmids, respectively. The promoterless pGL4.11 plasmid was included as negative control. NSCs were divided into 5 groups, transfected with the above constructs, and cultured 24 h under normoxic and hypoxic conditions, respectively. Then the promoter activities were quantified by luciferase assays. (b) Absolute expression levels of miR-199a-5p in NSCs under normoxic and hypoxic conditions are quantified by qPCR. miRNA copy numbers were calculated based on a standard curve generated using a synthetic LIN-4 RNA oligonucleotide. Abbreviation: RLU, relative luminescence unit. Error bars: s.d. , .
