非编码小分子RNA在纳米二氧化硅诱导细胞恶变中的作用

Small non-coding RNAs (miRNAs) are a kind of recently discovered endogenous nucleic acid molecules, which play a role in negative regulation of gene expression during various crucial cell processes such as differentiation, proliferation and apoptosis, and their abnormal expression are associated with kinds of diseases. Malignant transformation of human bronchial epithelial cells induced by nano-SiO2 particles was used as models and the miRNAs expression patterns during transformation prophase, early stage and malignant transformation period was detected, and the dynamic variation rule by microarray and quantitative RT-PCR was analyzed and the relationship between miRNA and other epigenetic patterns was also analyzed. The project will build the system of research on miRNAs functions and explore the role of miRNAs in cell transformation. Bioinformatics and were applied to design high efficient and characteristic program for prediction of miRNA target sequences, miRNA target genes in this project, and it will identify miRNA target genes by RNA interference (RNAi) in vitro. The project will reveal the roles of miRNAs in all stages of carcinogenesis induced by nano-SiO2 particles, and provide a new approach for elucidating the environmental carcinogenesis. The results will not only provide evidence for the safety evaluation of SiO2 nanoparticles , but also provide miRNA targets for early diagnosis and treatment of lung cancer.

非编码小分子RNA（miRNA）是近年来发现的对基因表达起负调控作用的内源性核酸分子，在细胞分化、增殖、凋亡等过程中起重要作用，其表达异常与多种疾病相关。本项目拟以纳米二氧化硅诱导人支气管细胞转化为模型，以miRNA芯片及定量PCR等检测转化前期、早期与恶变期miRNA表达，分析其动态变化规律及其在细胞转化过程中与基因组DNA甲基化及特异基因启动子甲基化的关系。建立miRNA功能研究体系，探索miRNA在细胞转化中的作用及与其他表观调控模式的关系。应用生物信息学设计高效特异的miRNA靶序列预测程序，预测miRNA靶基因，以慢病毒为载体的RNA干扰技术在细胞内鉴定miRNA靶基因。本项目将揭示miRNA在纳米二氧化硅诱导癌变过程中的作用。研究结果不仅可为纳米二氧化硅长期暴露的安全性评价提供依据，而且可为肺癌早期诊断和治疗提供miRNA水平上的靶点。

非编码小分子 RNA（miRNA）是近年来发现的对基因表达起负调控作用的内源性核酸分子，在细胞分化、增殖、凋亡等过程中起重要作用，其表达异常与多种疾病相关。本项目最终以纳米二氧化硅短期染毒及长期染毒恶性转化的人支气管细胞（16HBE）转化为模型，以 miRNA 芯片及定量 PCR 等检测转化P0、P10与P30代细胞 miRNA 表达，分析其动态变化规律及其在细胞转化过程中与基因组 DNA甲基化及特异基因启动子甲基化的关系。获得P0、P10、P30组细胞2007个miRNA的表达谱，与P0组相比，P10、P30表达逐渐上调的为25个，逐渐下调的为3个。选取表达差异明显的miR-494-3p、miR-19a-3p、miR-148b-3p进行qRT-PCR验证。与P0组相比，P10、P30的miRNA-494-3p表达水平逐渐下降（F=60.77，P<0.05），分别为0.45±0.08、0.28±0.07；miRNA-19a-3p表达水平分别为2.27±0.45、1.06±0.19（F=30.23，P<0.05）；miRNA-148b-3p的表达水平分别为1.78±0.29、0.88±0.19（F=30.05，P<0.05）。与对照组相比，5、10、20μg/mL nano-SiO2及20μg/mL μm-SiO2染毒组的miRNA-494-3p表达水平分别为0.99±0.04、1.38±0.19、2.13±0.14、0.81±0.25（F=57.03，P<0.05）；miRNA-19a-3p的表达水平分别为0.91±0.03、1.12±0.03、0.53±0.01、0.86±0.01（F=408.78，P<0.05）；miRNA-148b-3p的表达水平分别为0.95±0.02、1.22±0.00、0.54±0.02、1.15±0.04（F=264.14，P<0.05）。本项目将揭示 miRNA 在纳米二氧化硅诱导癌变过程中的作用。研究结果不仅可为纳米二氧化硅长期暴露的安全性评价提供依据，而且可为肺癌早期诊断和治疗提供 miRNA 水平上的靶点。