Stroma penetrating and immune modulating nanoparticles for image-guided therapy of pancreatic cancer

项目摘要 治疗抵抗是胰腺癌治疗面临的主要挑战。尽管最近取得了成功 在几种人类癌症类型的免疫检查点治疗中，胰腺癌对 免疫疗法。越来越多的证据表明，胰腺癌中致密的间质屏障阻碍了药物的治疗 递送和瘤内分布。基质的物理屏障和生物屏障 免疫抑制反应进一步限制了浸润性效应T细胞的数量和功能。目标是 该项目的目的是开发一种新的免疫治疗策略，通过联合传递肿瘤穿透性和 免疫调节热疗纳米粒和PD-L1抑制剂。我们创新的UPAR目标和基质 断裂配体由uPA的氨基末端片段(ATF)和基质的催化结构域组成 金属蛋白酶-14(ATFmmp14)。它针对肿瘤中的多种细胞类型，并促进纳米颗粒/药物 通过基质和细胞外基质屏障迁移到肿瘤细胞。ATFMMP14共轭磁体 携带阿霉素或SN38的纳米氧化铁(IONP)引导下的磁共振成像(MRI) 肿瘤内纳米粒/药物的靶向传递和对胰腺癌患者的强大治疗效果 衍生异种移植(PDX)和Kras驱动的转基因小鼠肿瘤模型。值得注意的是，有针对性地交付 瘤内注射IONPs可促进免疫效应细胞的侵袭，降低免疫抑制作用 细胞，将免疫的“冷”胰腺肿瘤转变为“热”肿瘤。我们进一步开发了超小型IONP 使用工程PD-L1封闭肽的PD-L1抑制剂(Nano-IPD-L1)。我们证明了Nano-IPD-L1 全身给药后选择性积聚在胰腺肿瘤中。纳米IPD-L1的联合递送 ATFMMP14-IONP/药物增强瘤内给药并显著抑制小鼠肿瘤生长 胰腺癌模型。因此，我们假设通过共同作用改善胰腺肿瘤的药物释放。 基质穿透ATFMMP14-IONP/SN38和Nano-IPD-L1的治疗效果显著 通过直接杀伤肿瘤细胞、调节免疫抑制间质和阻断PD-L1功能发挥作用 从细胞毒性T细胞产生强烈的反应。在拟议的研究中，我们将首先调查和优化 ATFMMP14-IONP/SN38与Nano-IPD-L1共给药小鼠胰腺的剂量和疗效 肿瘤模型(Aim1)。随后进行无创性MRI检查以评估经鼻腔内注射IONP和肿瘤反应 ATFMMP14-IONP/SN38与Nano-IPD-L1联合治疗转基因小鼠及胰腺的实验研究 肿瘤PDX模型(AIM 2)。最后，ATFMMP14在肿瘤内蓄积增强的效应- IONP/SN38和Nano-IPD-L1促进效应免疫细胞的渗透，调节基质 将在转基因小鼠中研究免疫抑制细胞和因子，以及激活细胞毒性T细胞 胰腺肿瘤模型(AIM 3)。这项研究的结果将为我们提供新的靶向治疗IONPs 以及免疫疗法，用于翻译这一晚期胰腺癌的新疗法。

Project Summary Resistance to therapy is the major challenge for the treatment of pancreatic cancer. Despite recent successes in immune checkpoint therapy of several human cancer types, pancreatic cancer showed a poor response to the immunotherapy. Increasing evidence reveals that a dense stromal barrier in pancreatic cancer blocks drug delivery and intratumoral distribution. The physical barrier of stromal and biological barrier from immunosuppressive responses further limit the number and function of infiltrating effector T cells. The objective of this project is to develop a new immunotherapy strategy by co-delivery of tumor penetrating and immunomodulating theranostic nanoparticles and PD-L1 inhibitors. Our innovative uPAR targeted and stroma breaking ligand consists of the amino terminal fragment (ATF) of uPA and the catalytic domain of matrix metalloproteinase-14 (ATFmmp14). It targets multiple cell types in tumors and promotes nanoparticle/drugs migrating through stromal and extracellular matrix barriers to reach tumor cells. ATFmmp14 conjugated magnetic iron oxide nanoparticle (IONP) carrying Doxorubicin or SN38 enabled magnetic resonance imaging (MRI) guided targeted delivery of nanoparticle/drug in tumors, and strong therapeutic effect in pancreatic cancer patient derived xenograft (PDX) and Kras-driven transgenic mouse tumor models. Notably, targeted delivery of the theranostic IONPs into tumors promoted infiltration of immune effector cells and decreased immunosuppressive cells, converting an immune “cold” pancreatic tumor into a “hot” tumor. We further developed an ultrasmall IONP PD-L1 inhibitor (Nano-iPD-L1) using an engineered PD-L1 blocking peptide. We showed that Nano-iPD-L1 selectively accumulated in pancreatic tumors following systemic delivery. Co-delivery of Nano-iPD-L1 with ATFmmp14-IONP/drug enhanced intratumroal delivery and significantly inhibited tumor growth in a mouse pancreatic cancer model. Therefore, we hypothesize that improved drug delivery in pancreatic tumors by co- administrations of stroma penetrating ATFmmp14-IONP/SN38 and Nano-iPD-L1 leads to a strong therapeutic efficacy through direct tumor cell killing, modulating immunosuppressive stroma, and blocking PD-L1 function to generate a strong response from cytotoxic T cells. In the proposed study, we will first investigate and optimize dose and therapeutic efficacy of co-delivery of ATFmmp14-IONP/SN38 and Nano-iPD-L1 in mouse pancreatic cancer models (Aim1). Followed by non-invasive MRI to assess theranostic IONP delivery and tumor response after the combined therapy using ATFmmp14-IONP/SN38 and Nano-iPD-L1 in transgenic mouse and pancreatic cancer PDX models (Aim 2). Finally, the effects of an enhanced intratumoral accumulation of ATFmmp14- IONP/SN38 and Nano-iPD-L1 on promoting infiltration of effector immune cells, modulating stromal immunosuppressive cells and factors, and activating cytotoxic T cells will be investigated in transgenic mouse pancreatic tumor models (Aim 3). Results of this study should provide us with new targeted theranostic IONPs and immunotherapy for translation of this novel therapy for advanced pancreatic cancer.