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

描述（由申请人提供）：大约90%的乳腺癌死亡是由于原发性肿瘤的转移性扩散引起的。目前癌症治疗的失败可能是由一小部分耐药和高转移性癌症干细胞（CSC）所解释的。尽管实验和临床研究已经证明了乳腺癌和其他实体瘤中存在CSC，但对可以通过血液循环系统扩散到远处部位，形成转移的CSC知之甚少。主要障碍是技术限制（例如，低灵敏度）来鉴定在流动的不同血细胞的大背景中散布的少量CTC中的罕见干细胞CTC。该提案的总体目标是使用集成的高灵敏度激光方法和新型多功能低毒纳米颗粒进行体内分子靶向、定量检测、富集和消除干细胞CTC。我们将通过以下具体目标实现这一目标：具体目标1：开发一种集成的多光谱高灵敏度光声/光热（PA/PT）平台，具有多功能PA/PT纳米探针，用于多峰分子检测，富集和消除乳腺干细胞CTC。干细胞CTC体内研究的技术平台将通过三种创新方法的整合来开发：1）高灵敏度，深穿透和非侵入性的激光光声（PA）技术; 2）生物相容性功能化的混合金-磁性纳米管（GMNT）;和3）激光光热（PT）消除干细胞CTC。具体目标二：使用人乳腺癌的小鼠模型评估用于检测和消除从母体肿瘤自然脱落的干细胞CTC的新平台的诊断和治疗能力。将开发干细胞CTCs的体内定量检测和磁富集，以了解干细胞CTCs对转移起始和进展的意义，并提供有效的分子靶向和激光消除对常规治疗耐药的干细胞CTCs的新方法。一般而言，体外（目标1）和体内（目标2）PA/PT纳米颗粒策略的联合使用应验证癌症干细胞CTC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，可以将所提出的方法快速转化为患有任何转移性癌症的患者。公共卫生相关性：实现这一目标与公共卫生的相关性源于该技术的潜力，即允许循环癌细胞的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物，以及评价放射治疗，激光治疗和化疗的疗效。一种耐用、低成本、便携、对人类安全的医疗器械，用于日常使用（如果需要）可以在各种临床情况下开发和设想：（1）将大多数患者的肿瘤分为高风险和低风险转移类别;（二）优化常规治疗方案以通过允许通过循环癌症的计数来评估临床应答来实现降低的毒性和最大功效干细胞;（3）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学疗法或放射疗法有抗性时;（4）当原发性肿瘤的进展与循环癌细胞的出现平行时，癌症的早期诊断;（5）前哨淋巴结和手术部位在肿瘤切除前后的评估，分别用于边缘评估和残留细胞检测。

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.