A Wholly Protein-based Self-assembly Nanoplatform for TNBC-specific Combination Therapy

摘要 三阴性乳腺癌(TNBC)是一种独特的乳腺癌类型，它不表达或 过表达雌激素受体(ER)、孕激素受体(PR)和HER2。在过去的几十年里， TNBC的标准护理仍然是高毒性的化疗，在更有效的治疗方面进展甚微。 为了解决尚未满足的迫切需求，开发针对TNBC的靶向治疗，我们开发了一种完全 基于蛋白质的纳米平台，称为ProNano，由两个重组蛋白质组成，包括第一个和 弹性蛋白样多肽(ELP)纳米核，在表面显示多个钙调蛋白结合短肽， 第二种是重组钙调素蛋白，与一种高度稳定的模块化蛋白在基因上融合 具有肿瘤归巢或治疗特征的结构域。ELP纳米核与TNBC的对接- 靶向模块与具有治疗特征的功能模块一起产生双功能ProNanos，该ProNanos 可用于肿瘤归巢给药，用于TNBC的联合治疗。三 这个项目将追求具体的目标。第一个具体目标是开发一个ProNano平台，允许 基于其表面抗原表达谱的可调靶向TNBC细胞。第二个具体目标是 开发一种双功能ProNano平台，允许肿瘤特异性阻断Wnt信号的异常 TNBC的治疗。第三个具体目标是开发一种双功能ProNano平台，使肿瘤- 特异性抑制ENPP1催化的胞外cGAMP水解酶联合免疫治疗 TNBC。本项目开发的双功能ProNano平台具有以下几个主要优势 传统的纳米平台，包括所有蛋白质成分，都可以进行精确的基因工程， 以所需比率定向和自组装的肿瘤定位和/或治疗部分的引入 不需要任何化学偶联，并使用高度稳定和易于表达的模块多肽 无免疫原性或免疫原性低。尽管我们专注于针对TNBC的靶向治疗，但ProNano平台 在这个项目中开发的可以通过简单地改变肿瘤来很容易地适应其他癌症类型 目标模块。

Abstract Triple-negative breast cancer (TNBC) is a unique type of breast cancer that does not express or overexpress estrogen receptor (ER), progesterone receptor (PR), and HER2. During the past several decades, the standard care of TNBC remains the highly toxic chemotherapy with little progress in more effective treatments. To address the urgent unmet need to develop targeted therapies specific for TNBC, we developed a totally protein-based nanoplatform called ProNano that is composed of two recombinant proteins, including the first an elastin-like polypeptide (ELP) nanocore that displays multiple calmodulin-binding short peptides on the surface, and the second a recombinant calmodulin protein genetically fused with a highly stable and modular protein domain possessing either tumor homing or therapeutic features. The docking of the ELP nanocore with a TNBC- targeting module together with a functional module with therapeutic feature results in bifunctional ProNanos that can be used for tumor-homing delivery of therapeutic agents for the combination therapy for TNBC. Three specific aims will be pursued in this project. The first specific aim is to develop a ProNano platform that allows tunable targeting of TNBC cells based on their surface antigen expression profiles. The second specific aim is to develop a bifunctional ProNano platform that allows tumor-specific blockade of the aberrant Wnt signaling for the treatment of TNBC. The third specific aim is to develop a bifunctional ProNano platform that allows tumor- specific inhibition of the ENPP1-catalyzed hydrolysis of extracellular cGAMP for combination immunotherapy of TNBC. The bifunctional ProNano platforms developed in this project have several major advantages over conventional nanoplatforms, including all protein components each can be precisely and genetically engineered, oriented and self-assembled introduction of both tumor homing and/or therapeutic moieties at desired ratios without need of any chemical conjugation, and use of highly stable and easily expressed modular polypeptides with no or low immunogenicity. Although we focus on the targeted treatment for TNBC, the ProNano platforms developed in this project can be easily adapted to address other cancer types simply by changing the tumor targeting module.