双调蛋白反义核酸表达对裸鼠乳腺癌血管生成的抑制作用

目的 研究双调蛋白（AR）反义RNA表达对乳腺癌血管生成的抑制作用。方法 乳腺癌NS2T2A1细胞经AR反义cDNA质粒转染后,经筛选获得表达AR反义RNA的AR-AS1及AR-AS3克隆,转染空载体获得NS2T2A1 V对照细胞,接种裸鼠皮下形成肿瘤。研究条件培养液对人微血管内皮细胞（HMEC）增殖的影响,以EL1SA法测定细胞血管内皮生长因子（VEGF）分泌量。以定量RT-PCR分析肿瘤组织的VEGF表达水平。以免疫组化法标记CD31研究肿瘤内血管数量。结果 HMEC在AR-AS1和AR-AS3细胞条件培养液中的增殖比例明显降低。AR-AS1和AR-AS3细胞VEGF分泌量亦降低。AR-AS1和AR-AS3肿瘤的血管数量仅有对照组的50％左右,且VEGF表达显著降低。结论 AR反义RNA表达可有效抑制乳腺癌的血管生成,应作为新治疗靶点进一步研究．

Amphiregulin antisense RNA expression inhibits angiogenesis of human breast cancer in nude mice

Objective To investigate the anti-angiogenic effect of amphiregulin(AR)antisense RNA expression in breast cancer. Methods Human AR cDNA antisense plasmid was transfected into NS2T2A1 cells (a human breast cancer cell line). Two selected clones expressed AR antisense RNA (AR AS1 and AR AS3 cell lines) in which AR protein expression was reduced. Control cell line NS2T2A1 V was obtained by empty vector transfection. These cells were injected subcutaneously into nude mice. The effects of conditioned media on proliferation of human microvascular endothelial cells (HMEC) were evaluated and VEGF secreted by the cells was measured by ELISA method. In tumor tissues, VEGF expression levels were measured by quantitative RT-PCR, and CD31-immunostaining was used for intra-tumoral vascular quantification. Results The proliferation index of HMEC cells grown in conditioned media with AR AS1 and AR AS3 was significantly reduced in comparison with that of control cells, accompanied by a decreased VEGF secretion. In tumors derived from AR AS1 and AR AS3 cells, intra-tumoral vascularization was reduced to about 50% of that derived from control cell line, accompanied with a decrease of VEGF expression. Conclusion Amphiregulin antisense RNA expression inhibits efficiently the angiogenesis in breast cancer, suggesting this growth factor could represent a novel therapeutic target in breast cancer.