Effects of tyrosine kinase receptor B-brain-derived neurotrophic factor signal pathway on the secretion of vascular endothelial growth factor and matrix metalloproteinase-9 of neuroblastoma / 中国小儿急救医学

ABSTRACT

Objective To study the effects of tyrosine kinase receptor B-brain-derived neurotrophic factor (TrkB-BDNF) signal pathway on the secretion of vascular endothelial growth factor (VEGF) and matrix metalloproteinases-9(MMP-9) of neuroblastoma.Methods We used all-trans retinoic acid (ATRA) to induce the high expression of TrkB in the SH-SY5Y cell line,and then added the ectogenid BDNF to activate the TrkB-BDNF and its three downstream signal pathways.TrkB-BDNF signal pathway was inhibited by specific tyrosine kinase inhibitor K252a.The three downstream signal pathway was respectively inhibited by LY294002 (the phosphatidylinositol 3-hydroxy kinase (PI3 K) pathway inhibitor)、U73122 (the phospholipase C pathway inhibitor) 、U0126(the mitogen activated protein kinase pathway inhibitor).Enzyme linked immunosorbent assay was used to detect the concentration of VEGF and MMP-9 protein in the SY5Y cell culture supernatants.Results VEGF [(485.89 ± 109.99) pg/ml] and MMP-9 [(15.73 ± 1.72) pg/ml] protein levels in neuroblastoma cells cultured in serum-free media in the group of ATRA + BDNF were significantly higher than that of the control group and ATRA alone group(P ＜0.05).VEGF [(272.42 ±86.33) pg/ml]and MMP-9 [(5.25 ± 1.44) pg/ml] protein levels in the group of ATRA + BDNF + K252a were significantly lower than those of the ATRA + BDNF group(P ＜ 0.05) and had no significant difference compared with the control group and the ATRA alone group(P ＞0.05).VEGF [(314.12 ±24.68) pg/ml] and MMP-9 [(4.91 ± 1.08) pg/ml] protein levels in the group of ATRA + BDNF + LY294002 were significantly lower than those of the ATRA + BDNF group(P ＜ 0.05) and had no significant difference compared with the control group and the ATRA alone group(P ＞0.05).VEGF [(444.08 ±64.49) pg/ml] and MMP-9 [(13.28 ±3.38) pg/ml] protein levels in neuroblastoma cells cultured in serum-free media in the group of ATRA +BDNF + U73122 had no significant difference compared with the ATRA + BDNF group(P ＞ 0.05).VEGF [(429.97 ± 19.95) pg/ml] and MMP-9 [(13.96 ± 4.45) pg/ml] protein levels in neuroblastoma cells cultured in serum-free media in the group of ATRA + BDNF + U0126 had no significant difference compared with the ATRA + BDNF group(P ＞ 0.05).Conclusion Activation of TrkB-BDNF signal pathway can increase the synthesis and secretion of VEGF and MMP-9 in human neuroblastoma cells.TrkB-BDNF signal pathway may be through activating its downstream PI3K pathway to increase the synthesis and secretion of VEGF and MMP-9 in human neuroblastoma cells.The synthesis and secretion of VEGF and MMP-9 can be inhibited by blocking the TrkB-BDNF signal pathway with K252a or blocking its downstream signal pathway PI3 K with LY294002.