Preliminary Study Of The Interaction Mechanism Between Basic Fibroblast Growth Factor And Angiogenin

Tumor angiogenesis is the formation of new blood vessels on the basis of originalvascular tumor growth, playing an important role in tumor growth, metastasis and invasion.Vascular endothelial growth factor and inhibitory factor are in equilibrium in normalreproductive and developmental process. However in some diseases especially cancer,angiogenesis becomes uncontrolled. Tumor growth and metastasis depend on angiogenesis.There are many growth factors involved in the angiogenesis process. People have identified avariety of cell growth factors directly or indirectly influence the growth of endothelial,including basic fibroblast growth factor and angiogenin.Nowadays, many people study on the mechanism of tumorigenesis, mainly focus on oneor a few vascular endothelial growth factors or angiogenesis inhibitor. However, little isknown about the synergy amang a variety of angiogenesis factor, how to regulate tumorangiogenesis and how to directly inhibit a particular factor. After10years of research, ourlaboratory find that there is a negative feedback regulation between angiogenin and basicfibroblast growth factor. Angiogenin binds to the promoter region of basic fibroblast growthfactor. We found that the combined region was between-970bp to-834bp in the promoter, andangiogenin regulated the expression of bFGF throuth the region.On the basis of preliminary study of our laboratory, we continued to explore theinteraction mechanism between angiogenin and bFGF. First, we explored whetherangiogenin regulated the expression of bFGF throuth directly combined with bFGF promoter.Second, we constructed prokaryotic expression vector containing angiogenin gene andeukaryotic expression vector containing bFGF gene. We obtained the fusion protein ofangiogenin. And then we usded GST pull down technology to verify whether angiogenincombined with bFGF at protein levels in vitro. The results showed that: We have successfullyconstructed the prokaryotic expression vector pGEX-2T-angiogenin, and successfullyexpressed the recombinant protein in E.coli. We purified recombinant protein which bindedwith Glutathione Sepharose4B beads. At the same time we successfully constructed theeukaryotic expression vector pKH3-bFGF. Finally, we showed that there was no directlyinteraction between angiogenin and bFGF in vitro.