Investigating apoferritin-encapsulated antitumour theranostics` delivery - to overcome drug-resistance mechanisms.

研究脱铁铁蛋白封装的抗肿瘤治疗诊断剂的递送——以克服耐药机制。

• 批准号: 2621903
• 金额: --
• 依托单位: University of Nottingham
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2621903
• 关键词: Investigating; apoferritin; encapsulated; antitumour; theranostics

Investigation of novel approaches to cancer treatment has attracted considerable research efforts. Particularly challenging are i) development of brain cancer therapies; ii) overcoming drug-resistance. Through development of biocompatible protein-based nanostructures, it is possible to deliver better treatment options able to target specific sites, overcome drug resistance and offer reduced systemic toxicity. Promising anticancer agents with therapeutic potential but limited solubility and weak targeting have been brought to clinic by this approach. However, the need to understand i) interactions between encapsulated agents and cells/tissue; ii) how drug-resistance can be bypassed remain. Apoferritin (AFt), a protein nanocage (12 nm diameter and 8 nm internal cavity), used naturally to store and transport iron ions (as ferritin), will be used as a delivery vehicle. This protein capsule, comprising 24 heavy and light chains is amenable to protein engineering and manipulation by synthetic biology. We have demonstrated using horse spleen and recently recombinant human AFt that we can deliver cargoes including near-infrared PbS quantum dots (QDs), anti-cancer agents (e.g. EGFR tyrosine kinase inhibitor gefitinib, imidazotetrazine- and benzothiazole analogues) to a range of carcinoma cell lines. By exploiting i) cancer cells` enhanced expression of transferrin receptor (TfR1) and ii) the intrinsic binding properties of AFt, AFt-encapsulation confers a significant degree of cancer-selectivity. Corroborating this thesis, we recently demonstrated that TfR1-recognition can be abolished through mutagenesis of AFt at the TfR1 binding recognition site (Figure 1). Our hypothesis is that AFt-encapsulated cargo is endocytosed into the endosome and as pH falls in the late endosome and acidic lysosome, the AFt nanocage disassembles releasing its cargo which is then able to exert its therapeutic effect. We have also established that in 2D cell culture, AFt-encapsulation of temozolomide (TMZ) is able to overcome resistance to this methylating agent conferred by MGMT expression, DNA-mismatch repair (MMR) deficiency or p-glycoprotein (p-gp) expression. In this project we will define mechanisms by which AFt-delivery overcomes drug-resistance by studying AFt-uptake, -trafficking though tumour cells and cargo delivery.

癌症治疗新方法的研究吸引了大量的研究工作。特别具有挑战性的是 i) 脑癌疗法的开发； ii) 克服耐药性。通过开发生物相容性的基于蛋白质的纳米结构，可以提供更好的治疗方案，能够靶向特定部位，克服耐药性并降低全身毒性。通过这种方法，具有治疗潜力但溶解度有限且靶向性弱的有前景的抗癌药物已被引入临床。然而，需要了解 i) 封装制剂与细胞/组织之间的相互作用； ii) 如何绕过耐药性仍然存在。脱铁铁蛋白 (AFt) 是一种蛋白质纳米笼（直径 12 nm，内腔 8 nm），天然用于储存和运输铁离子（如铁蛋白），将用作递送载体。这种蛋白质胶囊由 24 条重链和轻链组成，适合通过合成生物学进行蛋白质工程和操作。我们已经证明，使用马脾和最近重组的人类 AFt，我们可以向一系列癌症递送包括近红外 PbS 量子点 (QD)、抗癌药物（例如 EGFR 酪氨酸激酶抑制剂吉非替尼、咪唑四嗪和苯并噻唑类似物）在内的货物细胞系。通过利用 i) 癌细胞增强的转铁蛋白受体 (TfR1) 表达和 ii) AFt 的内在结合特性，AFt 封装赋予了显着程度的癌症选择性。为了证实这一论点，我们最近证明，可以通过 TfR1 结合识别位点处的 AFt 诱变来消除 TfR1 识别（图 1）。我们的假设是，AFt 封装的货物被内吞到内涵体中，并且随着晚期内涵体和酸性溶酶体中 pH 值的下降，AFt 纳米笼分解释放其货物，从而能够发挥其治疗作用。我们还确定，在 2D 细胞培养中，AFt 封装的替莫唑胺 (TMZ) 能够克服 MGMT 表达、DNA 错配修复 (MMR) 缺陷或 p-糖蛋白 (p-gp) 表达所赋予的对该甲基化剂的耐药性。在这个项目中，我们将通过研究 AFt 摄取、肿瘤细胞运输和货物递送来定义 AFt 递送克服耐药性的机制。