Developing a Novel System for Cancer Therapy: Tumor-Targeted Inhibition of Oncogenic MicroRNAs

开发癌症治疗新系统：致癌 MicroRNA 的肿瘤靶向抑制

• 批准号: 9234508
• 负责人: Alexander Svoronos
• 金额: $ 2.83万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2018-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9234508
• 关键词: Affinity; Alpha Cell; Antisense Oligonucleotides; Apoptosis; Apoptotic; Aspartic Acid; Bacteriorhodopsins; Base Pairing; Binding; Biological Assay; Cancerous; Cell Line; Cell Proliferation; Cell membrane; Cells; Charge; Clinic; Clinical; Closure by clamp; Computer Simulation; Cytosol; DNA; Data; Development; Differential Equation; Disease; Dose; Environment; Equilibrium; Exhibits; Gene Targeting; Genes; Goals; Hydrophobicity; In Vitro; Individual; Length; Lymphoma; Malignant Neoplasms; Melanoma Cell; Messenger RNA; MicroRNAs; Modeling; Mus; Nature; Neoplasm Metastasis; Oligonucleotides; Oncogenic; Paper; Pathway interactions; Peptide Nucleic Acids; Peptides; Physiological; Play; RNA; Role; Solid Neoplasm; Solubility; System; Technology; Therapeutic; Therapeutic Agents; Tissues; Translating; Transmembrane Domain; Treatment Efficacy; Withdrawal; addiction; base; cancer cell; cancer regression; cancer therapy; cell type; clinically relevant; improved; in vivo; interest; melanoma; member; mouse model; neoplastic cell; novel; overexpression; peptide B; peptide G; predictive modeling; public health relevance; targeted cancer therapy; targeted delivery; targeted treatment; tumor; tumor specificity

 DESCRIPTION (provided by applicant): MicroRNAs are dysregulated in nearly all cancers. By inhibiting oncogenic or tumor suppressive messenger RNAs, miRNAs can have a significant effect on cancer development and pro- gression. There is thus great interest in modulating the levels of various miRNA species for the treatment of cancer. Among the most promising molecules for inhibiting oncogenic miRNAs (oncomiRs) are artificial anti-sense oligonucleotides known as peptide nucleic acids (PNAs). However, their delivery into tumor cells is a challenge, as they are relatively cell-impermeable. This challenge can be overcome via the use of pH (low) in- sertion peptide (pHLIP), a short helical peptide capable of inserting across a cell membrane to form a transmembrane helix at acidic pHs, but not at normal physiologic pH. At acidic pHs, PNAs attached as cargo molecules to the inserting end of pHLIP are delivered across the cell membrane and into the cytosol. Since tumors are acidic, the PNAs accumulate preferentially in tumors, thereby limiting off-target effects. Recently, proof-of-concept therapeutic efficacy of the pHLIP-PNA technology was established in a mouse model of 'on- comiR-addicted' lymphoma, which undergoes complete regression upon withdrawal of the oncomiR. However, as oncomiR addiction has yet to be observed in nature, this model is of limited clinical relevance. We hypothe- size that the pHLIP-PNA technology will also be effective in other models with different oncomiRs, and the technology can be enhanced by the use of short G-clamp gamma-modified PNAs (G-MP-γ-PNAs), which are smaller than the original PNAs but exhibit similar binding affinity and increased solubility. Specific Aims: This proposal is comprised of three specific aims The first aim is to demonstrate more robust therapeutic relevance while broadening the scope of the pHLIP-PNA technology to inhibit oncomiRs in other cancers, which would prove valuable for translating the technology to the clinic. To do this, we will demonstrate therapeutic efficacy in the highly robust and clinically relevant Braf/Pten mouse model for malignant melanoma. The second aim is to investigate the hypothesis that the use of short G-MP-γ-PNAs, due to their enhanced solubility and smaller size, will result in increased tumor-specificity and delivery of th pHLIP-PNA technology, thereby increasing the therapeutic efficacy. Lastly, the third aim of the proposal is to elucidate why certain miRNAs are oncogenic in some cancers but tumor suppressive in others, which is of critical importance to the development of oncomiR- inhibiting therapies. As an individual miRNA can target tens to hundreds of different mRNA molecules, some of which may be oncogenic while others are tumor suppressive, we hypothesize that it is the balance between the miRNA's oncogenic and tumor suppressive targets which determines whether the miRNA will have a net onco- genic or net tumor suppressive effect. A computational model we developed predicts this, and we now aim to provide experimental support for its predictions by switching a miRNA from oncogenic to tumor suppressive and vice versa in cell lines by modifying the expression level of one of the miRNA's oncogenic targets.

 描述(申请人提供)：microRNAs在几乎所有癌症中都是失调的。通过抑制致癌或肿瘤抑制信使RNA，miRNAs可以在癌症的发生和进展中发挥重要作用。因此，人们对调节各种miRNA物种的水平用于癌症治疗非常感兴趣。在抑制致癌miRNAs(OncomiRs)方面，最有希望的分子是被称为肽核酸(PNA)的人工反义寡核苷酸。然而，它们进入肿瘤细胞是一个挑战，因为它们相对不能渗透到细胞中。这一挑战可以通过使用pH(低)插入肽(PHLIP)来克服，PHLIP是一种能够在酸性PHS中插入细胞膜形成跨膜螺旋的短螺旋多肽，但在正常生理pH下不能。在酸性PHS中，PNA以货物分子的形式连接到PHLIP的插入端，穿过细胞膜进入细胞质。由于肿瘤是酸性的，PNA优先在肿瘤中蓄积，从而限制了靶外效应。最近，概念验证治疗的疗效 Phlip-PNA技术是在一种‘on-comiR成瘾’淋巴瘤小鼠模型上建立的，当oncomir停用时，这种淋巴瘤会经历完全消退。然而，由于肿瘤性成瘾在本质上尚未被观察到，该模型的临床意义有限。我们假设PHLIP-γ-PNA技术在其他不同肿瘤发生率的模型中也是有效的，并且可以通过使用短G-钳伽马修饰PNA(G-MP-PNA)来增强该技术，G-MP-PNA比原始PNA更小，但具有相似的结合亲和力和更高的溶解度。具体目标：这项建议包括三个具体目标：第一个目标是展示更强大的治疗相关性，同时扩大PHLIP-PNA技术的范围，以抑制其他癌症的肿瘤复发，这将被证明对将该技术转化为临床有价值。为此，我们将在高度稳健和临床相关的BRAF/PTEN小鼠模型中展示对恶性黑色素瘤的治疗效果。第二个目的是研究使用短G-MP-γ-PNA的假设，由于它们的溶解性增强和较小的尺寸，将导致提高肿瘤特异性和递送TH PHLIP-PNA技术，从而提高治疗效果。最后，该提案的第三个目的是阐明为什么某些miRNAs在一些癌症中是致癌的，而在另一些癌症中是肿瘤抑制的，这对肿瘤抑制疗法的发展至关重要。由于单个miRNA可以靶向数十到数百个不同的mRNA分子，其中一些可能是致癌的，另一些可能是肿瘤抑制的，我们假设是miRNA的致癌靶点和肿瘤抑制靶点之间的平衡决定了miRNA是具有净致癌还是净抑瘤作用。我们开发的一个计算模型预测了这一点，我们现在的目标是通过改变miRNA的一个致癌靶点的表达水平，在细胞系中将miRNA从致癌切换到肿瘤抑制，反之亦然，从而为其预测提供实验支持。