Fluorescent nanoparticles to improve resections of microscopic pancreatic tumors

摘要 胰腺癌的一个主要挑战是根据“治疗意图”防止肿瘤复发。 手术切除(5年生存率21%)。人们认为，在一部分患者中，导致 肿瘤复发是小的亚厘米和亚毫米病变，看不见，因此在治疗时未切除。 做手术。为了解决这个问题，研究人员正在开发新的荧光引导细胞减少术。 (FGCS)技术，目的是使外科医生能够在术中发现并切除亚厘米和亚毫米 肿瘤。这些技术用于管理荧光探针--如荧光偶联抗体、小分子 分子、多肽、量子点或纳米颗粒-定位于肿瘤从而有助于识别 肿瘤组织。肿瘤的定位通常通过两种广泛分类的靶向策略之一来实现： 通过增强渗透性和保留率(EPR)效应的“被动瞄准”；或通过 在探针中掺入靶向部分或抗体。然而，这些技术都不能 辨别亚厘米和亚毫米疾病。这项提议开发了一种新颖的、获得专利的荧光探头，即“高度... 荧光罗丹明标记可膨胀纳米颗粒“(HFR-ENP)，通过一种独特的材料靶向肿瘤- 基于目标的策略。该机制利用了纳米粒子聚合物的材料功能 (例如，肿胀)和肿瘤的基本病理生理特性(例如，代谢率增加) 实现肿瘤特异性定位，准确率达95%。我们假设通过使用HFR-ENPs来引导 细胞减少术治疗播散性亚厘米和亚毫米肿瘤，我们将显著提高总存活率 与非引导下的切除相比。初步数据表明：1)HFR-ENPs增加了5到10倍 与同等浓度的游离罗丹明进行荧光比较，并可用伽马灭菌 辐射而不显著损失该荧光；2)在临床上大规模生产HFR-ENPs(即， 1升批次)规模；3)体外和体内HFR-ENPs的无毒性；4)敏感和特异的定位 活体内亚厘米和亚毫米胰腺肿瘤；5)概念验证HFR-ENP引导的细胞减灭术 在体内切除大(&gt；1厘米)、亚厘米和亚毫米肿瘤。关于COM的两个关键的通过/不通过决定- 这项技术的商业化在这项提案中得到了解决。首先，为了能够在临床上使用，进行绝育 必须制定不改变HFR-ENP聚合物或猝灭罗丹明荧光的方案。 而且，在灭菌后，必须确认颗粒的体内功能/肿瘤定位。第二, 使用HFR-ENPs指导切除胰腺肿瘤，特别是胰腺癌和胰腺癌的益处 亚毫米肿瘤，必须通过体内细胞减少手术模型进行量化。因此，这样做的目的是 建议：1)用伽玛辐照灭菌HFR-ENPs，灭菌后确定肿瘤定位； 目的2)确定HFR-ENP引导下手术切除对生存率的改善作用。

ABSTRACT A primary challenge in pancreatic cancer is preventing tumor recurrence in patients following a “curative intent” resection procedure (5-year survival rate 21%). It is believed that, in a subset of patients, the primary cause of tumor recurrence is small sub-cm and sub-mm disease that is unseen and, therefore, un-resected at the time of surgery. To address this problem, researchers are developing new Fluorescently-Guided Cytoreductive Surgery (FGCS) techniques with the goal of enabling surgeons to intraoperatively detect and resect sub-cm and sub-mm tumors. These techniques administer a fluorescent probe—such as a fluorescently-conjugated antibody, small molecule, peptide, quantum dot or nanoparticle—that localizes to tumors thereby facilitating identification of tumor tissue. Localization to the tumor is generally achieved via one of two broadly classified targeting strategies: “Passive Targeting” via the enhanced-permeability and retention (EPR) effect; or, “Active Targeting” through the incorporation of a targeting moiety or antibody into the probe. However, none of these technologies is able to identify sub-cm and sub-mm disease. This proposal develops a novel, patented, fluorescent probe, the “highly- fluorescent rhodamine-labeled expansile nanoparticle” (HFR-eNP), that targets tumors via a unique Materials- Based Targeting strategy. This mechanism leverages both the material functionality of the nanoparticle polymer (e.g., swelling) and fundamental pathophysiological properties of tumors (e.g., increased metabolic rate) to achieve tumor-specific localization with >95% accuracy. We hypothesize that by using HFR-eNPs to guide cytoreductive surgery of disseminated sub-cm and sub-mm tumors, we will significantly improve overall survival compared to unguided resections. Preliminary data demonstrate: 1) HFR-eNPs possess 5- to 10-fold increased fluorescence compared to equivalent concentrations of free rhodamine and can be sterilized with gamma irradiation without significant loss of this fluorescence; 2) large-scale production of HFR-eNPs on a clinical (i.e., 1 liter batch) scale; 3) non-toxicity of the HFR-eNPs in vitro and in vivo; 4) sensitive and specific localization to sub-cm and sub-mm pancreatic tumors in vivo; and, 5) proof-of-concept HFR-eNP-guided cytoreductive surgery to remove large (>1 cm), sub-cm and sub-mm tumors in vivo. Two key Go/No-Go decisions regarding the com- mercialization of this technology are addressed in this proposal. First, in order to be used clinically, a sterilization protocol must be developed that does not alter the HFR-eNP polymer or quench the rhodamine fluorescence. And, following sterilization, the in vivo functionality/tumor localization of the particles must be confirmed. Second, the benefit afforded by using HFR-eNPs to guide the resection of pancreatic tumors, in particular sub-cm and sub-mm tumors, must be quantified through an in vivo cytoreductive surgery model. Thus, the aims of this proposal are: Aim 1) Sterilize HFR-eNPs via Gamma irradiation and confirm tumor localization post-sterilization; Aim 2) Determine the improvement to survival afforded by HFR-eNP-guided surgical resections.