IGF-IR反义寡核苷酸对胶质瘤细胞增殖的影响

目的 根据胰岛素样生长因子-受体（IGF-IR）基因序列设计了IGF-IR mRNA起始密码子下游的硫代磷酸型反义寡核苷酸和正义寡核苷酸，研究其对C6胶质瘤细胞增殖作用。方法 实验分为反义核酸组、正义核酸组和空白对照组，经细胞计数、MTT法研究反义核苷酸对胶质瘤细胞生长和增殖的抑制作用。并应用免疫细胞化学方法检测胶质瘤细胞IGF-IR和增殖细胞核抗原（PCNA）蛋白的表达。结果 反义寡核苷酸能有效地降低IGF-IR基因的表达，抑制体外培养的胶质瘤细胞的增殖，其抑制作用24h显效，96h仍有作用，反义寡核苷酸的抑制效果与其作用浓度有关。而正义寡核苷酸对其无抑制作用。同时可见反义寡核苷酸抑制增殖作用中，能明显下调PCNA蛋白的表达。结论 IGF-IR介导的IGF-I-IGF-IR的自（旁）分泌环对胶质瘤生长极其重要，通过IGF-IR反义寡核苷酸治疗能较有效地抑制胶质瘤细胞的增殖。

The inhibitory effects of IGE-IR antisense phosphorothioate oligodeoxynucleotide on the proliferation of malignant glioma cells

Objective The antisense phosphorethioate oligodeoxynucleotide(antisense ODNs) was designed to be complimentary to the 5'-portion of IGF-IR mRNA which is a few bp of rat cells downstream of the initiation codon. The purpose of this study is to evaluate the inhibitory effects of the antisense ODNs on the proliferation of C6 glioma cells. Methods According to different agents added in the media of cultured C6 cells, cultured glioma cells were allocated into antisense, sense and untreated control groups. Expressions of IGF-IR were analyzed by the immunocytochemical staining to verify the inhibition of antisense of ODNs on the growth of glioma cells. The cell growth was assessed through cell count, MTT assays and PCNA immunocytochemical staining. Results The antisense ODNs exhibited strong inhibition on the growth of cultured glioma cells in vitro, whereas sense ODNs did not significantly affect the cell growth. Analysis of immunocytochemical staining demonstrated that the expression of IGF-IR and PCNA proteins was greatly down-regulated in the antisense ODNs-treated cells. Conclusion Results in this study suggest that IGF-IR-mediated autocrine loop plays a crucial role in the proliferation of glioma cells, and the antisense strategy can inhibit the proliferation of glioma cells in vitro.