Reprogramming Tumor-Associated Macrophages in PDAC with MicroRNA Nano-Vectors

临床前和临床证据表明，肿瘤相关巨噬细胞（TAM）是 主要是支持免疫抑制、细胞侵袭、血管生成的M2表型， 转移和治疗抗性。 该项目的主要目的是评估microRNA（miR）-125b在双重（CD 44和CD 45）细胞中的递送。 M2 pep）靶向的基于透明质酸（HA）的自组装纳米颗粒，以影响肿瘤相关的 巨噬细胞（TAM）从主要的M2复极化为M1表型，以改善治疗效果 在胰腺导管KrasLSL-G12 D/+，p53 fl/fl基因工程小鼠（KPC-GEM）模型中 腺癌（PDAC）。 在我们的初步研究中，我们已经表明，功能化的HA块形成一个模块化的自我- 组装纳米平台，用于稳定包封核酸构建体，包括小干扰 核糖核酸这些靶向CD 44的核-壳纳米颗粒已经显示出有效的siRNA递送和下调。 体内抗凋亡基因的调节。Cieslewicz等人已经表明，M2 pep具有优先的 与其他细胞相比，在鼠M2极化TAM中的结合、快速内化和积累。在 我们的初步研究，我们已经观察到，M2 pep序列与HA自身的缀合， 组装纳米颗粒显示这些纳米颗粒在体外M2中的优先积累 巨噬细胞 该项目的具体目标如下： 图12是封装在HA-PEI/HA-PEG/HA-m2 pep纳米组装体中的miR-125 b双链体的表征。Aim-2 研究将针对纳米组装体的体外评价，以重新激活巨噬细胞， 它们调节促炎细胞因子的能力。Aim-3研究将讨论抗肿瘤药物的评价 HA-PEI/HA-PEG/HA-125中包封的miR-125 b双链体的治疗反应和转移抑制 在PDAC的KPC-GEM模型中，m2 pep与吉西他滨加nab-紫杉醇组合。 这项研究在评价巨噬细胞复极（从主要的M2到M3）方面具有高度意义。 M1）作为治疗PDAC的治疗策略，并使用巨噬细胞靶向的基于HA的 纳米颗粒递送微小RNA以完成复极化。基于HA的创新模块化 纳米平台是极其通用的，以提供有效的核酸包封、有效载荷保护和 特异性递送至TAM以用于有效复极化。

Preclinical and clinical evidence suggests that tumor-associated macrophages (TAMs) are predominantly of the M2 phenotype that supports immuno-suppression, cellular invasion, angiogenesis, metastasis, and therapeutic resistance. The main objective of this project is to evaluate microRNA (miR)-125b delivery in a dual (CD44 and M2pep) targeted hyaluronic acid (HA)-based self-assembling nanoparticles to affect tumor associated macrophage (TAM) repolarization from a predominant M2 to M1 phenotype for improved therapeutic effect in in a KrasLSL-G12D/+, p53fl/fl genetically-engineered mouse (KPC-GEM) model of pancreatic ductal adenocarcinoma (PDAC). In our preliminary studies, we have shown that functionalized HA blocks form a modular self- assembling nano-platform for stable encapsulation of nucleic acid constructs, including small interfering RNA. These CD44-targeted core-shell nanoparticles have shown effective siRNA delivery and down- regulation of anti-apoptotic genes in vivo. Cieslewicz, et al. have shown that M2pep has preferential binding, rapid internalization, and accumulation in murine M2-polarized TAM's compared to other cells. In our preliminary investigation, we have observed that conjugation of M2pep sequence to the HA self- assembling nanoparticles shows preferential accumulation of these nanoparticles in vitro in M2 macrophages. The specific aims of the project are as follows: Aim-1 studies will focus on formulation and characterization of miR-125b duplex encapsulated in HA-PEI/HA-PEG/HA-m2pep nano-assemblies. Aim-2 studies will be directed towards in vitro evaluation of the nano-assemblies to re-polarize macrophages and their capacity to regulate pro-inflammatory cytokines. Aim-3 studies will address evaluation of the anti-tumor therapeutic response and inhibition of metastasis of miR-125b duplex encapsulated in HA-PEI/HA-PEG/HA- m2pep in combination with gemcitabine plus nab-Paclitaxel in a KPC-GEM model of PDAC. This study is highly significant in evaluating macrophage repolarization (from predominant M2 to M1) as a therapeutic strategy for the treatment of PDAC and using macrophage targeted HA-based nanoparticles to deliver microRNA for accomplishing repolarization. The innovative modular HA-based nano-platform is extremely versatile to afford efficient nucleic acid encapsulation, payload protection, and specific delivery to TAM in vivo for efficient repolarization.