Cell proliferation assay
To determine cellular proliferation, MTT Cell Proliferation assay kit (10009365, Cayman, USA) was used. Briefly, cells were seeded in 96-well plate (105 cells/well) in 200μL DMEM medium for 24 h. Untreated cells were used as a negative control. After incubation 10μL of MTT reagent was added to each well, gently mixed for 1 minute on orbital shaker, and then incubated 3 hours at 37°C in a 5% CO2. Further 100μL of crystal dissolving solution was added to each well to dissolve the formazan crystals, producing a purple solution, and incubated for 18 hours in a 37°C at CO₂ incubator. The absorbance of each sample were measured at 570nm on BioTek Citation 5 Cell Imaging Multimode reader.