In vivo molecular laser detection and treatment of circulating cancer stem cells

描述(申请人提供)：大约90%的乳腺癌死亡是由原发肿瘤的转移扩散引起的。目前癌症治疗的失败可能是由一小部分耐药和高转移的癌症干细胞(CSCs)来解释的。虽然实验和临床研究已经证明CSCs存在于乳腺和其他实体肿瘤中，但对CSCs可以通过血液循环系统扩散到远处形成转移知之甚少。主要的障碍是现有检测方法的技术局限性(例如，低灵敏度)，无法识别在大量不同血细胞流动的背景中扩散的少数干细胞CTCs。这项建议的总体目标是利用集成的高灵敏度激光方法和新颖、多功能、低毒的纳米颗粒，在体内进行分子靶向、定量检测、浓缩和消除茎CTCs。我们将通过以下具体目标来实现这一目标：具体目标1：开发一个集成的多光谱高灵敏度光声/光热(PA/PT)平台，带有多功能PA/PT纳米探针，用于多维分子检测、浓缩和消除乳腺干CTCs。将结合三种创新方法开发茎CTC体内研究的技术平台：1)高灵敏度、深度穿透和非侵入性的激光光声(PA)技术；2)生物兼容的金磁性纳米管(GMNTs)；3)激光光热(PT)消除茎CTC。具体目标2：使用人类乳腺癌的小鼠模型，评估检测和消除从亲本肿瘤自然脱落的干细胞的新平台的诊断和治疗能力。为了了解干细胞在转移发生和发展中的意义，并为有效的分子靶向和激光消除耐药的干细胞提供一种新的途径，将开展干细胞体内CTCs的定量检测和磁性富集法的研究。总体而言，体外(Aim 1)和体内(Aim 2)PA/PT纳米颗粒策略的联合使用应验证癌症干细胞在乳腺癌中的作用的概念验证。考虑到使用激光和基于金的纳米颗粒的安全性，我们预测，通过开发用于患者CTC诊断和治疗的便携式腕部设备，所提出的方法可以迅速推广到任何转移性癌症患者。公共卫生相关性：实现这一目标与公共健康的相关性源于这项技术的潜力，该技术允许对循环癌细胞进行常规体内生物监测，作为癌症患者微转移发展和癌症复发的早期标志，以及评估放射治疗、激光治疗和化疗的疗效。一种坚固、低成本、便携、安全的人类日常使用的医疗设备(如有必要)可以在各种临床场景中开发和设想：(1)将大多数患者的肿瘤分为高风险和低风险转移类别；2)优化传统治疗方案，通过对循环肿瘤干细胞的计数来评估临床反应，以实现降低毒性和最大疗效；(3)使用周期性激光血液净化进行诊断，以降低转移发展的风险，特别是当肿瘤对标准化疗或放射治疗具有抵抗力时；(4)当原发肿瘤平行发展并出现循环癌细胞时，可早期诊断癌症；(5)在切除肿瘤前后分别评估前哨淋巴结和手术部位，以评估边缘和检测残留细胞。

DESCRIPTION (provided by applicant): Approximately 90% of all deaths from breast cancer arise from metastatic spread of a primary tumor. The failure of current cancer treatment may be explained by a small subset of therapy-resistant and highly metastatic cancer stem cells (CSCs). Although experimental and clinical studies have demonstrated the presence of CSCs within breast and other solid tumors little is known about CSCs that can disseminate by blood circulatory system to distant sites, forming metastases. The major obstacle is technical limitations (e.g., low sensitivity) of current assays to identify rare stem CTCs among a small population of CTCs disseminated in a large background of different blood cells in flow. The overall goal of this proposal is in vivo molecular targeting, quantitative detection, enrichment and elimination of stem CTCs using integrated high sensitivity laser methods and novel, multifunctional low-toxic nanoparticles. We will accomplish this goal through the following specific aims: Specific Aim 1: Develop an integrated multispectral high-sensitivity photoacoustic/photothermal (PA/PT) platform with multifunctional PA/PT nanoprobes for multipex molecular detection, enrichment and elimination of breast stem CTCs. The technological platform for stem CTC research in vivo will be developed by integration of three innovative approaches: 1) highly sensitive, deeply penetrating and noninvasive laser photoacoustic (PA) techniques; 2) biocompatible functionalized hybrid gold-magnetic nanotubes (GMNTs); and 3) laser photothermal (PT) elimination of stem CTCs. Specific Aim 2: Estimate diagnostic and therapeutic capability of new platform for detection and elimination of stem CTCs naturally shedding from a parent tumor using a mouse model of human breast cancer. The quantitative detection and magnetic enrichment of stem CTCs in vivo will be developed in order to understand significance of stem CTCs for metastases initiation and progression and to provide a novel approach for effective molecular targeting and laser elimination of stem CTCs resistant to conventional therapies. In general, the combined use of in vitro (Aim 1) and in vivo (Aim 2) PA/PT-nanoparticle strategies should verify a proof-of-concept for the role of cancer stem CTCs in breast cancer. Taking into account the safety of using laser and gold-based nanoparticles, we predict that proposed approach can be translated quickly to patients with any metastatic cancers by development of a portable wrist device for patient's CTC diagnosis and treatment. PUBLIC HEALTH RELEVANCE: The relevance to the public health of achieving this goal derives from the potential of this technology to allow the routine in vivo biomonitoring of circulating cancer cells as early markers for micrometastatic development and cancer recurrence in cancer patients, as well as evaluation of the efficacy of radiation therapy, laser therapy, and chemotherapy. A robust, low-cost, portable, safe for humans medical device for routine daily use (if necessary) can be developed and envisioned in various clinical scenarios: (1) classifying most patients' tumors into high- and low-risk-metastatic categories; 2) optimizing a conventional therapeutic regimen to achieve decreased toxicity and maximum efficacy by permitting the assessment of the clinical response through the counting of circulating cancer stem cells; (3) diagnostic with periodic laser blood purging, to reduce risk of metastasis development, especially when a tumor is resistant to standard chemotherapy or radiation therapy; (4) the early diagnosis of cancer when there is parallel progression of a primary tumor and the appearance of circulating cancer cells; and (5) the assessment of sentinel nodes and surgical sites before and after tumor removal for margin evaluation and detection of residual cells, respectively.