Figure 2.

GDF15 promotes VEGFA expression in U373 glioblastoma cells but not proliferation and migration of U373 cells. (A) U373 cells were treated with 100 ng/mL rhGDF15 protein for 3 days in a medium with different serum concentrations (2% or 10% fetal bovine serum) and the cells were counted daily. (B) The cells were seeded on 12-well plates (3 × 10⁵ cells/well) and cultured for 1 day. The monolayer was scratched and incubated for 24 h in a medium containing 2% serum. Subsequently, the cells were stained with a fixation solution containing trypan blue. (C) The VEGFA mRNA levels in rhGDF15-stimulated U373 cells were measured using quantitative reverse transcription polymerase chain reaction. (D) Soluble VEGF was quantified in the enriched culture medium containing 2% serum using enzyme-linked immunosorbent assay from days 1–3. Data are presented as the mean ± standard deviation of three experiments. *p < 0.05, **p < 0.01, and ***p < 0.001 compared with control group. ns, no significance.