脂质体介导的IGF-1R反义寡核苷酸抗胰腺癌的实验研究

The growth inhibition of human pancreatic cancer cells by lipofectin mediated IGF-1R antisense oli-gonucleotides

目的研究辐射促进脂质体(lipofectin)介导的胰岛素样生长因子-1受体(IGF-1R)反义寡核苷酸(ASON)抑制人胰腺癌细胞系PC-3的生长及接种裸鼠后的成瘤性。方法PC-3细胞经不同剂量60Co照射后,绘制剂量存活曲线,选择照射剂量。用噻唑蓝(MTT)比色法比较脂质体介导的ASON(lipo-ASON)直接转染与联合照射转染对PC-3细胞的抑制效果,用流式细胞术和逆转录-聚合酶链反应(RT-PCR)方法检测两种转染方法对PC-3细胞凋亡率及IGF-1RmRNA表达的影响。裸鼠种植PC-3细胞,肿瘤直径为5mm时,比较不同条件下(肿瘤局部照射与不照射)瘤内注射IGF-1Rlipo-ASON对肿瘤的抑制情况。结果Lipo-ASON联合照射对胰腺癌细胞的抑制率(86.3%)、凋亡率(53.06%)及IGF-1RmRNA水平降低程度(降低79.2%)均明显高于未照射组(51.1%、20.23%和45.6%),差异有显著性。照射后瘤内注射lipo-ASON组的肿瘤体积明显小于其他各组,空白对照组与联合照射的lipo-ASON组、Lipo-ASON组肿瘤体积差异有显著性(P<0.01)。结论针对IGF-

Objective To study the enhancement of the growth inhibition by irradiation to human pancreatic cancer cells （PC-3） transfected by lipofeetin-mediated insulin-like growth factor-1 receptor （IGF-1 R） antisense oligonucleotides （ASON） and its tumorigeneeity in nude mice. Methods The curves of the survived PC-3 cells after 6^60Co γ radiation in varied dose were drawn and the optimal radiation dose was selected. Two transfeetion ways were utilized, transfected by IGF-1R lipo-ASON combined with or without ionizing radiation. Cells growth inhibition was shown by methyl thiazolium tetrazolium （ MTT）. The mRNA expression of IGF-IR was examined by reverse transcription-polymerase chain reaction （RT-PCR）. Flow eytometry was used to demonstrate apoptotie changes in both groups. After the transplanted tumors have grown in nude mice, lipo-ASON was injected in both groups, then the effects of inhibition were compared. Results The inhibitory effect of lipo-ASON （86.3%） , the apoptotic rate （53.06%） and the decreasing of IGF-1R mRNA （79.2%） in irradiation group was higher than non-irradiation group. Also, the differences were significant in tumor volume in irradiation group comparing to the control group（ P 〈 0.01 ）. Conclusion The ASON of IGF-1R can effectively inhibit the growth of tumor, and its inhibition can be enhanced by irradiation.