The role of granulocyte colony stimulating factor in metastatic colon cancer

原发结直肠癌患者外周血粒细胞集落的表达存在显著差异 刺激因子和受体(GCSF/R)，但这些不同水平的表达对转移的影响 CRC的潜力是未知的。这项工作的长期目标是发现和测试新的治疗靶点 CRC的基础是对肿瘤微环境的更好理解。这个项目的总体目标是 目的是确定GCSF信号升高在多大程度上增加结直肠癌的转移，并询问 潜在的因果机制。中心假设是GCSF信号的增加促进了CRC的发生 转移。这项拟议研究的基本原理是，了解GCSF信号如何可能 增强结直肠癌转移潜能将为考虑将GCSF作为治疗靶点奠定关键基础 这种致命的疾病。在强劲的初步数据的指导下，这一假设将通过完成三个 具体目标：(1)测定血清GCSF水平和转移瘤GCSF表达的程度 和GCSFR与转移性结直肠癌患者的预后相关；(2)确定 不同水平的GCSF和GCSFR的表达以细胞固有的方式促进结直肠癌的转移；以及(3) 确定CRC GCSF信号、全身性中性粒细胞和肿瘤相关中性粒细胞 相互作用可增强结直肠癌的转移。在目标1下，将评估两种可能的相关性：(1) 疾病特定结果和血清中GCSF水平，以及(2)疾病特定结果与GCSF之间的关系 和肿瘤微环境中的GCSFR水平。慢病毒转导、shRNA和CRISPR技术 将在目标2中用于修饰人和小鼠CRC细胞以过度表达、下调或取消两者 受体和配基。这将允许定量评估表达水平对细胞固有的影响 转移潜能。最后，在Aim 3中，将使用小鼠的微观和宏观转移结直肠癌模型来 确定CRC GCSF信号如何影响中性粒细胞(包括全身和肿瘤微环境)以及如何影响 这些相互作用会影响体内的转移潜能。这将使这项研究超越临床相关性。 并在体外工作，以深入了解CRC GCSF信号在完整的 免疫系统。在申请人看来，这种方法是创新的，因为它调查了以前的 在人类结直肠癌中高度过度表达的促炎细胞因子与其作用之间未经研究的联系 结合患者数据和体外机制研究结直肠癌患者肿瘤相关中性粒细胞 以及体内的工作。这一方法具有重要意义，因为它有望通过产生 详细了解一种新观察到的人类CRC变异的影响。具体地说，细胞固有的 并将确定在CRC转移中可变的GCSF和GCSFR表达的细胞外在效应， 进一步考虑将GCSF信号作为晚期结直肠癌的治疗靶点。

Primary colorectal cancers (CRC) demonstrate significant variability in expression of granulocyte colony stimulating factor and receptor (GCSF/R), yet the effect of these varying levels of expression on the metastatic potential of CRC is unknown. The long-term goal of this work is to discover and test new therapeutic targets for CRC based on an improved understanding of the tumor microenvironment. The overall objective of this project is to determine the extent to which elevated GCSF signaling increases metastasis in CRC, and to interrogate the underlying causal mechanisms. The central hypothesis is that increased GCSF signaling promotes CRC metastasis. The rationale for the proposed research is that an understanding of how GCSF signaling may enhance CRC metastatic potential will lay critical groundwork for consideration of GCSF as a therapeutic target for this lethal disease. Guided by strong preliminary data, this hypothesis will be tested by completing three specific aims: (1) determine the extent to which serum GCSF levels and metastatic tumor expression of GCSF and GCSFR correlate with outcomes in CRC patients with metastatic disease; (2) determine the extent to which varying levels of GCSF and GCSFR expression enhance CRC metastasis in a cell-intrinsic manner; and (3) determine the extent to which CRC GCSF signaling, systemic neutrophils, and tumor associated neutrophils interact to augment CRC metastasis. Under Aim 1, two possible correlations will be assessed: (1) between disease specific outcomes and GCSF levels in serum, and (2) between disease specific outcomes, and GCSF and GCSFR levels within the tumor microenvironment. Lentiviral transduction, shRNA, and CRISPR technology will be used in Aim 2 to modify human and murine CRC cells to over-express, downregulate, or abrogate both the receptor and ligand. This will allow quantitative evaluation of the influence of expression level on cell-intrinsic metastatic potential. Finally, in Aim 3, mouse models of micro- and macro-metastatic CRC will be used to determine how CRC GCSF signaling affects neutrophils (both systemic and tumor microenvironment) and how these interactions affect metastatic potential in vivo. This will extend the study beyond the clinical correlations and in vitro work to provide insight into the role of CRC GCSF signaling in the complex environment of an intact immune system. The approach is innovative, in the applicant's opinion, because it investigates a previously unexamined link between a pro-inflammatory cytokine that is highly over-expressed in human CRC and the role of tumor associated neutrophils in CRC using a combination of data from patients, as well as mechanistic in vitro and in vivo work. The approach is significant because it is expected to advance the study of CRC by producing a detailed understanding of the effects of a newly observed variation in human CRC. Specifically, the cell-intrinsic and cell-extrinsic effects of variable GCSF and GCSFR expression within CRC metastasis will be determined, advancing consideration of GCSF signaling as a therapeutic target in advanced CRC.