血管抑制素基因抑制结肠癌细胞增殖及肿瘤血管生成的研究

目的:研究血管抑制素基因体外对结肠癌细胞增殖的抑制及体内对肿瘤血管生成的抑制,探讨血管抑制素基因对结肠癌的抑制作用。方法:构建重组质粒pcDNA3.1( )／angio,用脂质体转染法将重组质粒、空白载体导入结肠癌细胞Colo205,培养细胞观察细胞生长,绘制细胞生长曲线,计算增殖抑制率,然后将pcDNA3.1( )／angio、pcDNA3.1( )／Colo205、Colo205分别接种至裸鼠右侧颈部皮下,观察肿瘤的生长,测量肿瘤体积,计算抑瘤率,免疫组化检测肿瘤组织中微血管密度(MVD)、血管内皮生长因子(VEGF)的表达。结果:体外pcDNA3.1( )／angio组细胞的生长速度略慢于pcDNA3.1( )／Colo205、Colo205组,但差异无统计学意义(P>0.05);体内pcDNA3.1( )／angio组细胞的致力显著降低,瘤体增长缓慢,抑瘤率较高(P<0.01),瘤体组织中MVD及VEGF的表达较低(P<0.05);pcDNA3.1( )／Colo205、Colo205两组之间的差异无统计学意义(P>0.05)。结论:在体外血管抑制素不直接影响结肠癌细胞Colo205的生物学特性,但在体内可强烈抑制肿瘤的生长,其机制可能是通过降低血管生成因子而抑制肿瘤的新生血管生成,发挥抑制肿瘤作用。

Effect of Angiostatin Gene on Inhibiting Cell Proliferation of Colon Carcinoma and Tumor Angiogenesis

jective: To study the effect of angiostatin gene on cell proliferation of colon carcinoma and tumor angiogenesis in vivo, and discuss the inhibitive effect of angiostatin gene on colon carcinoma. Methods:Reconstructing plasmid pc DNA3. 1( )angio was constructed, then the plasmid and blank vector were transducted into colon carcinoma cells by lipofection mothod. Cell growth curve was drawn and proliferation-inhibiting rate was calculated after cell culture. Then pcDNA3. 1 ( )/angio, pcDNA3. 1( )/Colo205, Colo205 were respectively inoculated into hypoderm of right-sided nuchae of nude mice. Tumor growth speed was observed, tumor volume was calculated, and microvascular density (MVD) and expression of VEGF were checked by immunohistochemistry. Results:In vitro, cell growth speed of pcDNA3. 1( )/angio group was slower than that of pcDNA3. 1 ( )/Colo205 group and Colo205 group, but there was no statistic significance ( P>0. 05). In vivo, carcinogenic potence of the pcDNA3.1( )/angio group was lower, growth speed of tumor tissue was lower and tumor-inhibiting rate was higher ( P <0. 01), and MVD and VEGF expression in the tumor tissue were lower than the other two groups (P <0. 05). The difference between pcDNA3.1( )/Colo205 group and Colo205 group was not significant ( P >0. 05). Conclusion: Angiostatin has no effect on biologic property of Colo205 directly in virto, while it can inhibit tumor growth evidently in vivo, the mechanism of which may be related to inhibiting tumor angiogenesis by decreasing VEGF.