Thai Sheau-Fung, Wallace Kathleen A, Jones Carlton P, Ren Hongzu, Prasad Raju Y, Ward William O, Kohan Michael J, Blackman Carl F
J Nanosci Nanotechnol. 2015 Jan;15(1):492-503. doi: 10.1166/jnn.2015.9202.
The effect of titanium dioxide nanoparticles (nano-TiO2 Degussa p25) treatment of human lung epithelial cells (BEAS-2B) was examined by analyzing changes in messenger [mRNA] and microRNA [miRNA]. BEAS-2B cells were treated with 0, 3, 10, 30 or 100 μg/ml nano-TiO2 for 1 day (for mRNA analysis) or 3 days (for miRNA analysis). Differentially expressed mRNA and miRNA were analyzed using Affymetrix microarrays and Affymetrix miRNA microarrays, respectively. Although, the tested doses were not cytotoxic, there were alterations in both mRNA and miRNA expression. The expression of mRNA/miRNA changes were examined in MetaCore (GeneGo) and IPA (Ingenuity Pathway Analysis) to delineate associated canonical/signaling pathways. Canonical/signaling pathways altered by nano-TiO2 treatments included: cell cycle regulation, apoptosis, calcium signaling, translation, NRF2-mediated oxidative response, IGF1 signaling, RAS signaling, PI3K/AKT signaling, cytoskeleton remodeling, cell adhesion, BMP signaling, and inflammatory response. Many of the genes in these pathways are known to be regulated by the miRNAs whose expressions were altered by the nano-TiO2 treatment. The miRNA 17-92 cluster and let-7 miRNA family that are involved in lung cancer formation were altered by nano-TiO2 treatment. The miR-17-92 cluster, an oncogenic microRNA cluster, is induced while the tumor suppressor microRNA, let-7 family, is suppressed. The changes of let-7/KRAS signaling pathway was observed in all the doses treated. The observed changes in miRNA expression introduces an additional mechanistic dimension that supports the significance of the observed mRNA expression changes, and demonstrated that the nano-TiO2 in vitro treatment in human lung cells can cause diverse but coordinated pathway alterations associated with changes in in vivo response to tumorigenes.
通过分析信使核糖核酸（mRNA）和微小核糖核酸（miRNA）的变化，研究了二氧化钛纳米颗粒（纳米TiO₂德固赛p25）对人肺上皮细胞（BEAS-2B）的影响。BEAS-2B细胞分别用0、3、10、30或100μg/ml纳米TiO₂处理1天（用于mRNA分析）或3天（用于miRNA分析）。分别使用Affymetrix微阵列和Affymetrix miRNA微阵列分析差异表达的mRNA和miRNA。虽然测试剂量没有细胞毒性，但mRNA和miRNA表达均有改变。在MetaCore（GeneGo）和IPA（英睿思通路分析）中检查mRNA/miRNA表达变化，以描绘相关的经典/信号通路。纳米TiO₂处理改变的经典/信号通路包括：细胞周期调控、凋亡、钙信号传导、翻译、NRF2介导的氧化反应、IGF1信号传导、RAS信号传导、PI3K/AKT信号传导、细胞骨架重塑、细胞粘附、BMP信号传导和炎症反应。已知这些通路中的许多基因受miRNA调控，而miRNA的表达因纳米TiO₂处理而改变。参与肺癌形成的miRNA 17-92簇和let-7 miRNA家族因纳米TiO₂处理而改变。致癌性miRNA簇miR-17-92簇被诱导，而肿瘤抑制性miRNA let-7家族被抑制。在所有处理剂量中均观察到let-7/KRAS信号通路的变化。观察到的miRNA表达变化引入了一个额外的机制维度，支持了观察到的mRNA表达变化的重要性，并证明了纳米TiO₂在人肺细胞中的体外处理可导致与体内对肿瘤发生反应变化相关的多种但协调的通路改变。
