论文部分内容阅读
目的:验证mRNA二级结构保守性在反义药物设计中的作用,获得靶向HER-2 mRNA的优于已报道阳性药物的序列。方法:RNAstructure用于模拟HER-2 mRNA二级结构,设计21个反义硫代寡脱氧核苷酸(S-ODN)。用SK-BR-3乳腺癌细胞评价S-ODN体外活性,SPSS进行定量构效关系(QSAR)分析,RT-PCR检测S-ODN对HER-2表达的影响。结果:11个靶向模拟二级结构完全保守局域(LM)的S-ODN中,有9个获得低于或相似于HA4的IC_(50)值,且其IC_(50)值显著低于靶向部分保守与非保守LM的AS-ODN(P<0.05),靶二级结构单元膨胀环的碱基数,靶结构自由能在QSAR方程中有统计意义,多元回归R=0.967,P=0.005)。结论:针对模拟靶mRNA二级结构中高度保守LM部位进行反义药物设计可提高阳性率,并获得优于阳性对照的S-ODN。
OBJECTIVE: To verify the conservation of mRNA secondary structure in antisense drug design and to obtain sequences that are superior to those reported for positive drugs targeting HER-2 mRNA. METHODS: RNAstructure was used to mimic the secondary structure of HER-2 mRNA and 21 antisense oligodeoxynucleotides (S-ODNs) were designed. The activity of S-ODN in vitro was evaluated by SK-BR-3 breast cancer cells. Quantitative structure-activity relationship (QSAR) analysis was performed by SPSS and the effect of S-ODN on HER-2 expression was detected by RT-PCR. RESULTS: Nine of the 11 S-ODNs targeting the fully conserved domain (LM) of simulated secondary structure obtained IC50 (50) values lower or similar to HA4 with significantly lower IC50 values (P <0.05). The number of base pairs of expansion ring and the free energy of target structure of target secondary structure unit were statistically significant in QSAR equation. The multiple regression was R = 0.967, P = 0.005). CONCLUSIONS: Antisense drug design targeting highly conserved LM sites in the secondary structure of mimic’s target mRNA enhances the positive rate and achieves better S-ODN than the positive control.