MicroRNA Therapy for Lymph Node Metastatic Breast Cancer

描述(申请人提供)：本提案的目标是评估一种新的淋巴结转移性乳腺癌的纳米治疗方法。能够成像的纳米颗粒分布在肿瘤和淋巴管中，将被设计成携带锁定核酸(LNA)击倒探针，靶向microRNA-10b(miR-10b)和miR-21，miR-21与肿瘤细胞的增殖和生存有关。在我们的初步研究中，我们已经证明了所提出的方法的可行性。我们已经证明，用miR-10b靶向纳米片治疗乳腺浸润性肿瘤细胞，在仅应用1.5nmoles/ml LNA的情况下，miRNA-10b的表达下调88%，并消除肿瘤细胞的侵袭和迁移。在体内，我们获得的结果表明，在静脉注射到荷瘤小鼠后，肿瘤靶向版本的纳米片导致了体内成像可检测到的强大的肿瘤摄取，重要的是，消除了生物发光成像可检测到的肿瘤细胞从原发肿瘤到淋巴结的转移。如果在出现淋巴结转移后开始治疗，纳米地毯可以阻止转移过程。这些早期的发现构成了目前应用的基础，在该应用中，我们建议扩展这些研究，以调解转移的长期预防、阻止和消退。这将通过同时靶向促转移的miR10b和促增殖和抗凋亡的miR-21来实现。还将探索联合治疗和化疗。交付将与交付过程的并行非侵入性成像相结合。我们将评估转移负荷的变化，并将我们的成像结论与体外研究进行比较。

DESCRIPTION (provided by applicant): The goal of this proposal is to evaluate a new approach for nanotherapy of lymph node metastatic breast cancer. Imaging-capable nanodrugs, which distribute to tumors and the lymphatics will be designed to carry locked-nucleic acid (LNA) knockdown probes targeting microRNA-10b (miR-10b), known to mediate tumor invasion and migration of breast cancer cells and miR-21, implicated in tumor cell proliferation and survival. In our preliminary studies, we have demonstrated the feasibility of the proposed method. We have shown that treatment of invasive breast tumor cells with the miR-10b-targeted nanodrug results in an 88% downregulation of miRNA-10b with the application of just 1.5 nmoles/ml of LNA and abolishes the invasion and migration of the tumor cells. In vivo, we have obtained results suggesting that after intravenous delivery to tumor-bearing mice, a tumor-targeted version of the nanodrug leads to robust tumor uptake detectable by in vivo imaging and, importantly, results in elimination of bioluminescence imaging-detectable tumor cell metastasis from the primary tumor to lymph nodes. If treatment is initiated after the appearance of lymph node metastases, the nanodrug arrests the metastatic process. These earlier findings form the basis for the current application, in which we propose to extend these studies in order to mediate long-term prevention, arrest, and regression of metastases. This will be accomplished by concurrently targeting the pro-metastatic miR10b and the pro-proliferative and anti-apoptotic miR-21. Combination treatment with chemotherapy will also be explored. The delivery will be coupled with the concurrent non-invasive imaging of the delivery process. We will evaluate changes in metastatic burden and will compare our imaging conclusions to ex vivo studies.