血小板因子4基因转染对肺癌细胞中血管生成因子基因表达的影响

Effects of transduction hPF4 gene on the angiogenesis factors gene expression in human lung cancer cells

目的 :进一步探讨人血小板因子 4(hPF4)抑制血管生成的作用机制。方法 :构建含全长hPF4cDNA重组真核表达载体pcDNA3 hPF4,将其转染到人肺巨细胞癌细胞系PLA80 1D细胞内 ,应用RT PCR及免疫组化法观察肿瘤细胞自分泌的血管内皮生长因子 (VEGF)、碱性成纤维细胞生长因子 (bFGF)、白细胞介素 8(IL 8)等的mRNA和蛋白表达水平的变化。结果 :导入pcDNA3 hPF4,PLA80 1D细胞能稳定表达hPF4mRNA ,其VEGF、bFGF、IL 8的mRNA和蛋白表达水平均明显降低 ,表明hPF4可直接调控VEGF、bFGF、IL 8等基因转录 ,影响其蛋白质生物合成。结论 :提示hPF4可直接下调肿瘤细胞自分泌的VEGF、bFGF及IL 8等血管生成因子基因转录 ,抑制肿瘤细胞释放肿瘤血管生成因子 。

Objective:To study the inhibiting angiogenesis mechanism of human platelet factor 4(hPF4) Methods:A hPF4 gene recombinant expression vector was constructed by cloning hPF4 cDNA into the pcDNA3 vector, and was transferred by lipofectamin into hPF4 deficient human pulmonary giant cell carcinoma cell line (PLA801D) with lipofectamin The mRNA and protein expression level of PLA801D-hPF4 cell was detected by RT-PCR and immunocytochemistry Results:Stable expression of hPF4 mRNA in PLA801D-hPF4 cells was confirmed by RT-PCR The angiogenic factor VEGF、bFGF、IL-8 mRNA and protein expression of PLA801D-hPF4 cell was significantly inhibited compared with the controls These results demonstrate that transfection of hPF4 gene into lung cancer cells could reduce its angiogenic factors mRNA expression, so it also effects the composition of their protein Conclusion:These date indicated that down-regulated mRNA expression of the angiogenic factor in cancer cells can be one of the mechanisms of inhibiting angiogenesis of hPF4