Hank s balanced salt solution buffer

To measure cancer cell proliferation based on the amount of cellular DNA, the CyQuant no freeze (NF) Cell Proliferation Assay Kit (Invitrogen) was used according to the manufacturer's instructions. Briefly, Panc-1, HT29, MDA MB 435, and Colo205 cells were seeded in a 96-well plate (1 × 10⁴ cells/well) and left to attach to the wells overnight. The next day, the medium was removed and replaced with 50 μL medium containing different concentrations of selinexor (0–1 μmol/L). After an hour incubation with selinexor, the virus was added to different MOIs (MOI 0.5 – MOI 5), bringing the end volume of every well up to 100 μL. A 1× dye binding solution was prepared by adding 9 μL of the CyQuant NF Dye reagent in 4.5 mL Hank's Balanced Salt Solution buffer (Invitrogen). After 24, 48, 72, and 96 hours of incubation, the medium was removed from the cells and 50 μL of the 1x dye solution was added to all wells. The microplate was covered to protect it from light and was incubated for 30–60 minutes in a humidified 5% CO₂ incubator at 37°C. Subsequently, cell proliferation was quantified by measuring fluorescence with excitation at 485 nmol/L and emission detection at 530 nmol/L in the VarioSkan Lux Microplate reader (Thermo Fisher Scientific). All experiments were performed in quadruples and normalized to mock-treated cells.