Hepsin cleavable nanocapsules for precision medicine in prostate carcinoma (HEPSIN-NANOLYSIS

丝氨酸蛋白酶Hepsin在90%的前列腺癌病例中过表达，具有细胞外蛋白分解活性，并促进小鼠肿瘤的进展和转移。由于这些特点，肝素是前列腺癌诊断和治疗的一个有吸引力的靶分子。我们打算利用肝酶的酶活性来定点释放抗肿瘤药物。将开发和评价一种基于多肽的新型纳米药物载体系统。这些纳米载体将被设计为在前列腺癌细胞表面选择性地开放，从而在相当大程度上减少副作用的情况下实现特定和有效的治疗干预。LY294002是一种完全特征化的PI3-Kinase/AKT介导的信号转导的拮抗剂，它在前列腺癌细胞系中显示出强大的抗肿瘤活性，无论是单独还是与促凋亡和癌症特异性细胞因子TRAIL(肿瘤坏死因子相关的凋亡诱导配体)联合使用。通过将这些药物包裹在将要开发的纳米载体系统中，我们的目标是显著提高生物利用度和有效性，并将体内副作用降至最低。这一概念将通过在鸡绒毛膜尿囊膜(CAM)模型中诱导表达肝素的实验性前列腺癌移植瘤进行生物学评估。胶囊将使用反相微乳液方法制备。将优化共聚单体和合成策略。通过筛选基于珠粒的组合多肽文库，将实现对肝酶特异性靶序列的选择。将分析基于多肽的胶囊在生物介质中的聚集和吸附特性，以及表面性质的迭代适应，最终导致以下纳米载体：i)完全可生物降解；ii)在肿瘤中有效积聚，但不在血管或器官中；iii)揭示一个可被蛋白质分解的表面；iv)特定地可被肝素降解；v)当接触到具有酶活性的肝酶时，迅速释放其货物。这一跨学科项目将为即将到来的旨在系统开发和评估用于癌症治疗的酶可切割纳米载体的方法奠定基础。除了建立基于文库的筛选技术和纳米载体合成和加载的通用策略外，高度标准化的体外模型以及CAM异种移植模型中的体内分析将为临床前研究提供可靠的数据，这将在避免动物试验的情况下实现。

The serine protease hepsin is overexpressed in 90% of prostate cancer cases, exhibits pericellular proteolytic activity, and promotes tumor progression and metastasis in mice. Due to these features, hepsin is an attractive target molecule for both diagnosis and therapy of prostate cancer. We intend to use the enzymatic activity of hepsin for the site-specific release of antitumour drugs. A novel, peptide-based nanoscale drug carrier system will be developed and evaluated. The nanocarriers will be designed for selective opening at the surface of prostate cancer cells, thereby enabling specific and efficient therapeutic intervention under considerable reduction of side effects.LY294002, a thoroughly characterized antagonist of PI3-Kinase / AKT-mediated signalling, reveals potent anti-tumor activity in prostate cancer cell lines, either alone or combined with the pro-apoptotic and cancer-specific cytokine TRAIL (tumor necrosis factor related apoptosis-inducing ligand). By encapsulating these drugs in the nanocarrier system to be developed, we aim at a significant improvement of bioavailabilty and efficacy and a minimization of side effects in vivo. The concept will be biologically evaluated using experimental prostate cancer xenografts featuring inducible expression of hepsin in the chicken chorioallantoic membrane (CAM) model.The capsules will be prepared using the inverse miniemulsion method. Co-monomers and synthesis strategies will be optimized. The selection of a hepsin-specific target sequence will be achieved by screening of a bead-based combinatorial peptide library. Aggregation- and adsorption characteristics of peptide-based capsules in biological media will be analysed along with iterative adaptations of surface properties, ultimately leading to nanocarriers which i) are completely biodegradable; ii) efficiently accumulate in tumors, but not in vessels or organs; iii) reveal a surface which is accessible for proteolysis; iv) are specifically degradable by hepsin; and v) rapidly release their cargo upon exposure to enzymatically active hepsin protease. The interdisciplinary project will provide a groundwork for upcoming approaches aiming at the systematic development and evaluation of enzymatically cleavable nanocarriers for cancer therapy. In addition to the establishment of a library-based screening technology and a universal strategy for nanocarrier synthesis and loading, highly standardized in vitro models as well as in vivo analyses in the CAM xenograft model will provide reliable data in preclinical research, which will be achieved under avoidance of animal trials.