靶向HER-2 mRNA反义硫代寡核苷酸体外抗乳腺癌活性研究

Inhibitory Effect of Antisense Oligodeoxynucleotides Targeting HER-2 mRNA on Proliferation of Breast Cancer Cell Line in Vitro

目的研究以HER2mRNA为靶点的反义硫代脱氧寡核苷酸(SODNs)HA6722对HER2过表达乳腺癌细胞株MDAMB453体外增殖的抑制作用,及HA6722对肿瘤细胞HER2表达的影响。方法选择HER2过表达的MDAMB453细胞与HER2低表达的MDAMB231细胞,MTT法观察SODNs对肿瘤细胞增殖的影响,免疫细胞化学(ICC)与RTPCR方法研究SODNs对细胞HER2蛋白及mRNA表达的影响。结果HA6722可以剂量依赖方式抑制MDAMB453细胞的体外增殖,IC50值(41.8±8.1nmol·L-1,n=5,mean±s)显著低于对照序列Scramble6722(IC50=489.4±12.1nmol·L-1,n=5,P<0.01)。HA6722在蛋白水平与mRNA水平显著抑制MDAMB453细胞中HER2的表达;HA6722对MDAMB231细胞的体外增殖无显著影响(IC50=476.7±17.6nmol·L-1,n=5,P>0.05)。结论HA6722可序列特异性地抑制HER2过表达乳腺癌细胞的体外增殖,其抑制增殖作用与靶细胞HER2表达下调有关。

Objective To study the inhibitory effects of HER2 specific antisense oligodeoxynucleotide HA6722 on the HER2 overexpression human breast cancer cell line,MDA-MB-453, and to ascertain the mechanism through which HA6722 works. Methods MDA-MB-453 and MDA-MB-231 cell lines, which are HER2 over-and normal-espression, respectively, were set as our experimental cells. Inhibitory effects of HA6722 on these cells were detected by means of methyl thiazolyl blue （MTT）, HER2 protein piSS and HER2 mRNA were detected by immunocytochemistry and RT-PCR. Results Compared with its control sequence Scramble6722, HA6722 could inhibit the growth of MDA-MB-453 cell in vitro in a dose-dependent manner, the IC50value of HA6722 （41.8 ± 8.1nmol·L^-1 , n = 5） was significantly lower than that of scramble6722 （IC50 = 489. 4 ± 12. 1 nmol· L^-1, n = 5, P〈0. 01）. Furthermore, HA6722 could inhibit the expression of HER2 in MDA-MB-453 cells markedly at protein and mRNA level. On the other hand, HA6722 had no effects on the proliferation of MDA-MB-231 cell （IC50 = 476. 7±17.6nmol·L^-1 , n = 5, P〉0. 05）. Conclusion Antisense oligodeoxynucleotide HA6722 could inhibit the growth of breast cancer cell which is HER2 overexpression in sequence specific manner, and the inhibitory effects correlated with the down-regulation of HER2 in targeting cells.