Fig. 4.

Effect of RGD-IFN-α2a-core fusion proteins on tumor cell viability. Cells were seeded into 96-well plates and treated with different concentrations of PBS, NR, Q1, or Q2 for up to 5 days and then subjected to cell viability MTT assays. (a) Q1 and (b) Q2. *P<0.05, **P<0.01 and ***P<0.001 compared with the negative control (PBS group) or the NR group. IFN, interferon; MTT, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; NR, nitrate reductase; RGD, arginine–glycine–aspartic acid.