Hyperspectral Microendscopy to Monitor VEGF During Pancreatic Cancer Therapy

描述(申请人提供)：胰腺癌(Panca)是一种破坏性疾病，在所有恶性肿瘤中5年存活率最低(&lt；5%)；因此，迫切需要改进治疗方案。胰腺癌细胞和其他类型的癌细胞在治疗过程中上调其特定基因的表达，以促进肿瘤细胞的增殖和存活。例如，癌细胞可以增加细胞信号因子的产生，如细胞因子生长因子及其受体。血管内皮生长因子(VEGF)是多种细胞因子在肿瘤存活和转移中发挥作用的例证。Hasan研究小组和其他研究人员已经证明，在化疗、放射治疗和光动力疗法(PDT)等亚疗效细胞毒疗法的反应下，癌细胞上调了VEGF的表达。这种肿瘤反应通常会导致疾病复发和转移增加，这与治疗目标相矛盾。在研究减轻这种影响的策略期间，HASAN研究小组发现，在PDT后的短时间内，分泌的VEGF水平会升高。这一结果强调了开发工具在癌症治疗期间在线监测细胞因子的重要性。这项研究的总体目标是捕捉在PDT和抗血管内皮生长因子联合治疗过程中，原位小鼠胰腺癌模型中肿瘤血管内皮生长因子表达的时空动态。这项研究还将调查使用一种新开发的纳米颗粒靶向细胞内库的血管内皮生长因子的增强治疗结果。我们的第一个目标是构建一个微创、定量的分子成像系统。一个灵活的、直径亚毫米的光纤成像束将用于就地进入胰腺肿瘤并对其成像。该探头将与高光谱荧光检测系统连接，以便于严格量化分泌的血管内皮生长因子水平的相对变化。也就是说，图像的每个像素都将包含一个荧光发射光谱，并将对每个像素进行分析，以从组织的自发荧光中分离出抗血管内皮生长因子单抗-荧光团(我们将用来显示血管内皮生长因子的显像剂)。拟议的设计将使在纵向研究期间频繁成像成为可能。根据记录的血管内皮生长因子的表达和分泌动态，我们将实施针对适当组织间隔的抗血管内皮生长因子治疗剂的定时递送和最佳剂量(使用纳米构建物靶向细胞内的血管内皮生长因子，使用游离的阿瓦斯丁靶向细胞外的血管内皮生长因子)，以最佳地阻断血管内皮生长因子的活性。这项工作将提高图像引导的潘卡疗法改善治疗结果的潜力，并将利用纳米技术靶向和中和细胞内细胞因子生长因子池来研究改善治疗结果的机制。 公共卫生相关性：胰腺癌是一种毁灭性的疾病，是医学界预后最差的疾病之一。该项目旨在通过解决肿瘤存活和增殖的关键分子介质的时空动力学问题来改进胰腺癌的治疗。该项目集成了新的图像引导和纳米技术平台，在“正确的时间”和“正确的地方”提供治疗剂，以最佳地抑制癌细胞的存活和转移。

DESCRIPTION (provided by applicant): Pancreatic cancer (PanCa) is a devastating disease with the lowest 5-year survival rate of all malignancies (<5%); therefore, there is a desperate need for improved treatment regimens. Pancreatic cancer cells and other cancer cell types up-regulate their expression of specific genes during therapy to promote tumor cell proliferation and survival. For example, cancer cells can increase production of cellular signaling factors, such as cytokine growth factors and their receptors. Vascular endothelial growth factor (VEGF) exemplifies the multitude of cytokines that play a role in tumor survival and metastasis. The Hasan group and others have shown that VEGF expression is up-regulated by cancer cells in response to subcurative cytotoxic therapies, such as chemotherapy, radiotherapy and photodynamic therapy (PDT). This tumor response often leads to disease recurrence and increased metastasis, paradoxical to the goals of therapy. During investigation for strategies to mitigate this effect, the Hasan group has found that secreted VEGF levels are elevated during a short time window following PDT. This result underscores the importance for developing tools to monitor cytokines online during cancer therapy. The overall goal of the proposed research is to capture the spatiotemporal dynamics of tumoral VEGF expression in an orthotopic, murine PanCa tumor model during combined PDT and anti-VEGF therapy. This study will also investigate the enhanced treatment outocome found using a newly developed nanoparticle to target the intracellular pool of VEGF. Our first aim is to construct a minimally invasive, quantitative molecular imaging system. A flexible, submillimeter-diameter fiber-optic imaging bundle will be used to access and image pancreatic tumors in situ. This probe will be coupled to a hyperspectral fluorescence detection system to facilitate rigorous quantification of relative changes in secreted VEGF levels. That is, each pixel of the image will contain a fluorescence emission spectrum and each pixel will be analyzed to isolate the anti-VEGF monoclonal antibody-fluorophore conjugate fluorescence (the imaging agent we will employ to visualize VEGF) from the tissue autofluorescence. The proposed design will enable frequent imaging during longitudinal studies. Based on the recorded VEGF expression and secretion dynamics, we will implement timed delivery and optimal dosing of an anti-VEGF therapeutic agent targeted to the appropriate tissue compartments (using the nanoconstruct to target intracellular VEGF and free Avastin to target extracellular VEGF) to optimally block VEGF activity. This work will ases the potential for image-guided PanCa therapy to improve treatment outcomes, and will investigate the mechanism of impoved therapeutic outcome using nanotechnology to target and neutralize intracellular pools of cytokine growth factors. PUBLIC HEALTH RELEVANCE: Pancreatic cancer is a devastating disease with one of the worst prognoses in medicine. This project aims to improve pancreatic cancer treatment by addressing the spatiotemporal dynamics of key molecular mediators of tumor survival and proliferation. This project integrates new image-guidance and nanotechnology platforms to deliver therapeutic agents at the "right time" and to the "right place" for optimal inhibition of cancer cell survival and metastasis.