Luciferase reporter assay

Reporter gene assays were performed using a Dual Luciferase Assay kit (Promega, Madison, WI, USA). OVACAR-3 or HeLa cells were seeded to 12-well plates and incubated overnight at 37°C in a humidified atmosphere containing 5% CO₂. The cells were then co-transfected with 0.4 μg of a firefly luciferase-encoding reporter plasmid containing the interferon stimulated response element (ISRE) and 0.3 μg of pTK-RLuc plasmid containing the Renilla luciferase reporter gene. Transfections were performed with the Lipofectamine LTX reagent (Invitrogen, Carlsbad, CA, USA). At 24 h post-transfection, cells were treated with the indicated concentrations of R27T, and after an additional 16 h, the activities of firefly luciferase and Renilla luciferase were determined using a microplate reader (TECAN).