Figure 2. GM-CSF overexpression in A549 and tumor growth suppression by siAPE1. (A) Establishment of high GM-CSF expression in HBE cells (n=4); (B) Significant GM-CSF expression in cells after incubation with supernatant containing high levels of GM-CSF (n=4); (C) High GM-CSF expression in supernatant after incubation with supernatant containing high levels of GM-CSF (n=4); (D) Tumor growth inhibition by siAPE1 transfection compared with A549+GM-CSF group. **p < 0.01, ***p < 0.001.