Influence Of Basic Fibroblast Growth Factor On The Expression Of Angiogenin And Vascular Endothelial Growth Factor

Tumor vessel is the basis of tumor growth and tumor metastasis. Angiogenic factors are diffusible substances which can induce angiogenesis. Basic fibroblast growth factor(bFGF) which is widespread in bodies can promote neovascularity, and the overexpression of bFGF is closely related to tumor generation, development and prognosis. Angiogenin is a direct angiogenesis inducer, its expression is essential for melanoma progression and metastasis. Vascular endothelial growth factor(VEGF)can directly act on vascular endothelial cell with the strongest effect. VEGF is also regulated by some angiogenic factors' precurosors.Many studies have mainly focused on how single angiogenesis factor induces tumor angiogenesis and its effect on tumor growth and metastasis. Here, we investigated the influence of bFGF under-expression and over-expression on the expression of angiogenin and VEGF,and on the proliferation of A375 cell to further understand the relationship between bFGF, angiogenin and VEGF in tumor angiogenesis mechanism.We transfected bFGF gene in the sense and antisense orientation into A375 cells, and obtained stable bFGF under-expressing and over-expressing transfectants. We found that in the bFGF over-expressing transfectants, the expression of angiogenin protein was down-regulated; In contrast, in the bFGF under-expressing transfectants, the expression of angiogenin protein was up-regulated. The expression of VEGF was up-regulated in the bFGF over-expressing transfectants and down-regulated in the bFGF under-expressing transfectants. We also found that in the bFGF over-expressing transfectants, the cell proliferation was increased, and in the bFGF under-expressing transfectants, the cell proliferation was decreased.In conclusion, we demonstrated that the expression level of endogenous bFGF can regulate the expression of angiogenin and VEGF in A375 cells, and bFGF can promote the proliferation of A375 cells. Tumor physiological activity was determined by many angiogenic factors that act synergically , single angiogenic factor can not determine this process. It has an extensive prospect to clarify the interaction of angiogenic factors in cancer therapy since it can lead to find a new therapeutic approach.