Figure 2
MiR-520b sensitizes cells to chemotherapy drugs and irradiation, while minimal effect on cell growth. (A) Cells were transfected with the miR-520b over-expression plasmid (miR-520b) or the vector (pcDNA) and were cultured for 1 day. The miR-520b expression levels were determined. (B) The effects of miR-520b modulation on colony formation. A total of 1 × 105 cells were seeded in 6-well plates for 7 days to allow cell colony formation. The number of colonies was then counted. (C) The effects of miR-520b modulation on cell growth. A total of 1 × 106 cells were re-seeded in 100-mm plates and the cell numbers were determined daily up to 3 days. (D) To detect the chemosensitivity of the cells, the relative number of surviving cells was determined after treatment with various doses of cisplatin (0 to 4 μg/ml) for 2 days. (E) To determine radiosensitivity, the colony survival fractions were determined after the cells were irradiated with various doses (0 to 6 Gy). All the experiments were performed duplicate for three times, and the similar results were obtained. The error bars shown in the relevant figures indicated the standard deviation of the three independent experiments. (*p < 0.05, **p < 0.01, ***p < 0.001, n.s.: non-significance, t-test).
