小剂量紫杉醇联合重组人血管内皮抑素对乳腺癌MCF-7细胞抑制作用的实验研究

Inhibitory effect of low-dose paclitaxel combined with recombinant human endostatin on breast cancer MCF-7 cell line

目的:观察小剂量(40μg/ml)紫杉醇(Paclitaxel,PTX)联合重组人血管内皮抑素(Recombinant human endostatin,rh-ES)对人乳腺癌MCF-7细胞生长及其血管内皮生长因子(Vascular endothelial growth factor,VEGF)表达的抑制作用。方法:实验分为对照组(A组)、PTX组(B组)、rh-ES组(C组)及PTX+rh-ES组(D组)。用细胞计数板计数法测定各组药物作用于MCF-7细胞24 h后的细胞存活数并计算细胞抑制率。免疫细胞化学SABC法检测各组VEGF蛋白表达,RT-PCR法检测各组VEGFmRNA表达。结果:D组的细胞抑制率明显高于C组(P=0.002),但与B组比较无统计学差异(P=0.57)。D组的VEGF蛋白及mRNA的表达较其余3组明显减少,差异具有统计学意义(P<0.05)。细胞抑制率的增加与VEGF表达减少之间具有线性相关性(r=0.564,P<0.001)。结论:小剂量PTX与rh-ES联合应用可明显抑制乳腺癌MCF-7细胞生长及其VEGF表达,提示两者联用在抑制肿瘤血管生成方面具有协同作用。

Objective：To observe the low-dose（40 μg/ml） paclitaxel（PTX） combined with recombinant human endostatin（rh-ES） in inhibiting the growth of human breast cancer MCF-7 cell line and suppressing the gene expression of vascular endothelial growth factor（VEGF）. Methods： The experiment had four groups ： control group （group A）, group PTX （group B）, group rh-ES （group C） and group PTX ＋ rh-ES（group D）. It enumerated the surviving MCF-7 cells after 24 h, which were treated with the four methods.Inhibitory rate of cells of the four groups was calculated.The VEGF protein and mRNA expressions were detected by immunocytochemistry and RT-PCR. Results ：The inhibitory rate of group D was higher than that of group C（P=0.002）,but there was no statistic significance of inhibitory rate between group D and group B（P=-0.57）. When VEGF protein and mRNA expressions were compared between each group,those in group D were significantly lower than in the other three groups（P〈0.05）. The increased inhibitory rate of MCF-7 cells and the decreased expression of VEGF were in linear correlation （r=0.564, P〈0.001 ）. Conclusion：Low-dose PTX combined with rh-ES can obviously inhibit the growth of MCF-7 cell line and suppress gene expression of VEGF. Our results demonstrate the combined use of low-dose PTX and rh-ES has synergistic effects in inhibiting tumor growth and angiogenesis.