University Hospitals of Cleveland , Department of Pathology , Cleveland , Ohio 44106 , United States.
Bioconjug Chem. 2019 Mar 20;30(3):907-919. doi: 10.1021/acs.bioconjchem.9b00028. Epub 2019 Feb 21.
Long noncoding RNAs (lncRNAs), by virtue of their versatility and multilevel gene regulation, have emerged as attractive pharmacological targets for treating heterogeneous and complex malignancies like triple-negative breast cancer (TNBC). Despite multiple studies on lncRNA functions in tumor pathology, systemic targeting of these "undruggable" macromolecules with conventional approaches remains a challenge. Here, we demonstrate effective TNBC therapy by nanoparticle-mediated RNAi of the oncogenic lncRNA DANCR, which is significantly overexpressed in TNBC. Tumor-targeting RGD-PEG-ECO/siDANCR nanoparticles were formulated via self-assembly of multifunctional amino lipid ECO, cyclic RGD peptide-PEG, and siDANCR for systemic delivery. MDA-MB-231 and BT549 cells treated with the therapeutic RGD-PEG-ECO/siDANCR nanoparticles exhibited 80-90% knockdown in the expression of DANCR for up to 7 days, indicating efficient intracellular siRNA delivery and sustained target silencing. The RGD-PEG-ECO/siDANCR nanoparticles mediated excellent in vitro therapeutic efficacy, reflected by significant reduction in the invasion, migration, survival, tumor spheroid formation, and proliferation of the TNBC cell lines. At the molecular level, functional ablation of DANCR dynamically impacted the oncogenic nexus by downregulating PRC2-mediated H3K27-trimethylation and Wnt/EMT signaling, and altering the phosphorylation profiles of several kinases in the TNBC cells. Furthermore, systemic administration of the RGD-PEG-ECO/siDANCR nanoparticles at a dose of 1 mg/kg siRNA in nude mice bearing TNBC xenografts resulted in robust suppression of TNBC progression with no overt toxic side-effects, underscoring the efficacy and safety of the nanoparticle therapy. These results demonstrate that nanoparticle-mediated modulation of onco-lncRNAs and their molecular targets is a promising approach for developing curative therapies for TNBC and other cancers.
长链非编码 RNA（lncRNA）凭借其多功能性和多层次的基因调控，成为治疗三阴性乳腺癌（TNBC）等异质复杂恶性肿瘤的有吸引力的药物靶点。尽管有多项关于 lncRNA 在肿瘤病理学中的功能的研究，但使用传统方法对这些“不可成药”的大分子进行系统靶向治疗仍然是一个挑战。在这里，我们通过纳米颗粒介导的致癌 lncRNA DANCR 的 RNAi 来展示有效的 TNBC 治疗，DANCR 在 TNBC 中显著过表达。通过多功能氨基酸脂质 ECO、环状 RGD 肽-PEG 和 siDANCR 的自组装，制备了靶向肿瘤的 RGD-PEG-ECO/siDANCR 纳米颗粒，用于系统递药。用治疗性 RGD-PEG-ECO/siDANCR 纳米颗粒处理的 MDA-MB-231 和 BT549 细胞在长达 7 天的时间内 DANCR 的表达降低了 80-90%，表明有效的细胞内 siRNA 递药和持续的靶基因沉默。RGD-PEG-ECO/siDANCR 纳米颗粒介导了优异的体外治疗效果，显著降低了 TNBC 细胞系的侵袭、迁移、存活、肿瘤球体形成和增殖。在分子水平上，DANCR 的功能缺失通过下调 PRC2 介导的 H3K27-三甲基化和 Wnt/EMT 信号，以及改变 TNBC 细胞中几种激酶的磷酸化谱，动态影响致癌网络。此外，在荷有 TNBC 异种移植物的裸鼠中以 1mg/kg siRNA 的剂量系统给予 RGD-PEG-ECO/siDANCR 纳米颗粒，导致 TNBC 进展得到强有力的抑制，没有明显的毒副作用，突出了纳米颗粒治疗的疗效和安全性。这些结果表明，纳米颗粒介导的对癌基因 lncRNA 及其分子靶标的调节是开发 TNBC 和其他癌症的治愈疗法的有前途的方法。
