[Effects of small interfering RNA targeting basic fibroblast growth factor on proliferation and apoptosis of glioma cell line U251]

Basic fibroblast growth factor (bFGF), a member of the fibroblast growth factor (FGF) family, is a multifunctional cytokine participating in the process of wound healing, tissue repairing, proliferation and differentiation of immature neural cells. We previously found that bFGF is overexpressed in glioma cells, and could stimulate the vascularization and cell proliferation of glioma. This study was to explore the effects of bFGF small interfering RNA (siRNA) on the proliferation and apoptosis of glioma cell line U251.

Four bFGF siRNAs (siRNA1-4) and one random siRNA were synthesized using chemical method and transfected into U251 cells. The U251 cells cultured with Opti-MEM I (no serum media) were used as normal control. The expression of bFGF in transfected U251 cells was detected by reverse transcription-polymerase chain reaction (RT-PCR) and SP immunohistochemistry. Cell proliferation was detected by MTT assay; cell apoptosis was detected by flow cytometry.

At 48 h after transfection, the mRNA levels of bFGF in U251 cells were 0.95+/-0.02 in normal control group, 0.95+/-0.02 in negative control group, 0.85+/-0.02 in siRNA-1 group, 0.76+/-0.04 in siRNA-2 group, 0.65+/-0.04 in siRNA-3 group, and 0.56+/-0.03 in siRNA-4 group; at 72 h after transfection, the mRNA levels of bFGF were 0.95+/-0.04, 0.84+/-0.05, 0.81+/-0.05, 0.80+/-0.05, 0.77+/-0.04, and 0.53+/-0.05, respectively. Among the 4 siRNAs, siRNA-4 showed the strongest effect. The proliferation inhibition rate of U251 cells was significantly higher in siRNA-4 group than in negative control group [(66.39+/-1.23)% vs. (56.3+/-1.45)% at 48 h after transfection, (40+/-2.6)% vs. (14.74+/-0.62)% at 72 h, P <0.05].

The optimal bFGF siRNA can inhibit bFGF expression and proliferation of glioma U251 cells.