Defining pro-tumourigenic neutrophil phenotypes and tumour-neutrophil interactions to identify targets for therapy in metastatic colorectal cancer

死于结直肠癌的患者是转移性疾病的结果。结直肠转移最常见的部位是肝脏。如果肝转移能够及早被发现，那么患者在手术后会收到最好的结果。可悲的是，有几组患者在肝切除后的表现非常差。这项研究旨在找出手术后表现不佳的患者，更好地了解他们的疾病生物学，并为他们提供未来针对其癌症的个体化靶向治疗的希望。为了开发新的治疗方法，我对结直肠癌患者进行了评估，这些患者在切除结直肠肝转移瘤后早期复发，与癌症相关的生存率较低。公认的是，在癌细胞周围有高水平支持性结缔组织的患者，其转移范围内的预后较差，这一点得到了我们的患者队列分析的进一步支持。我的工作表明，这些患者的转移瘤中有非常多的中性粒细胞，这是最常见的白细胞。使用模拟人类胰腺癌和结直肠癌的小鼠模型，我已经证明在这些转移性癌症中，中性粒细胞在支持疾病进展方面发挥着重要作用，这表明这种现象可能并不是晚期结直肠癌所特有的。引人注目的是，干扰中性粒细胞进入肝脏可以减少肝脏中肿瘤的数量，当给予激活免疫系统的治疗时，我可以提高癌症小鼠模型的存活率。直到最近的研究才表明，中性粒细胞可以以不同的方式表现，在健康和疾病中扮演不同的角色。这些细胞是非常可塑性的，很容易改变它们表达的东西，以响应来自癌细胞的信号，因此可以根据环境显示出促癌和抗癌的特性。正是中性粒细胞的这种可塑性可能有助于调节免疫系统的行为的治疗。仍然存在的问题是：中性粒细胞如何支持转移癌的进展？存在于结直肠癌转移瘤中的中性粒细胞表达哪些标志，与健康相比，这些标志如何支持其在癌症进展中的作用？一个重要的考虑因素是，中性粒细胞对正常免疫非常重要，以对抗疾病，通过特别针对肿瘤促进中性粒细胞，未来的治疗可能会与先天免疫谈判困难。在这项建议中，我将详细说明哪些患者具有与转移相关的大量中性粒细胞，通过使用肿瘤产生的分子因子的序列根据患者的疾病生物学对患者进行亚型。使用由行业合作伙伴纳米串开发的令人兴奋的新技术，然后我将通过对肝脏肿瘤中的中性粒细胞群体进行深入的空间定向评估来解决存在哪些类型的中性粒细胞的问题。一旦我确定了与侵袭性疾病生物学相关的中性粒细胞群体，我将使用我在实验室开发的最先进的结直肠癌转移小鼠模型，在与人类疾病最相关的生命系统中移除不同群体的中性粒细胞，并使用复杂的显微镜评估转移过程对转移过程的影响。这些评估将展示这些有针对性的方法对中性粒细胞的行为、与免疫细胞和肿瘤细胞的相互作用以及最终对结直肠癌扩散机制的影响。以高通量的方式使用小鼠模型，在那里我测试转移肿瘤系统中敲除的中性粒细胞上的一些分子因子，我将能够识别中性粒细胞上的潜在靶点，这些靶点可以在未来的临床试验中用于治疗。

Patients that die from colorectal cancer do so as a result of metastatic disease. The most common site for colorectal metastases is the liver. If liver metastases can be detected early then patients receive the best outcomes following surgery. Sadly there are groups of patients that do very poorly following liver resection. This research looks to identify the patients that do poorly following surgery, understand their disease biology better and provide them with the hope of individually targeted therapy for their cancer in the future.To develop new therapies I have performed assessment of patients with colorectal cancer that have early recurrence and poor cancer related survival following resection of their colorectal liver metastases. It is accepted that patients with high levels of supportive connective tissue surrounding cancer cells, within their metastases have poorer outcomes and this is further supported by analysis in our cohort of patients. My work has shown that these patients have very high numbers of neutrophils, the most common white blood cell, within their metastases. Using mouse models that mimic human pancreatic and colorectal cancer I have shown that in these metastatic cancers neutrophils play an important role in supporting progression of disease, suggesting this phenomenon may not be unique to advanced colorectal cancer. Strikingly, interfering with neutrophils travelling to the liver reduces the number of tumours in the liver and when therapies that activate the immune system are given I can improve survival of the cancer mouse models. Only recently studies have suggested that neutrophils can behave in different fashions, adopting different roles in health and disease. These cells are very plastic and readily change what they express in response to signals from cancer cells and therefore can demonstrate both pro and anti-cancer properties depending on context. It is this plasticity of neutrophils that may lend itself to therapies that modulate the behaviour of the immune system.The questions that remain are: how do neutrophils support progression of metastatic cancer?; What markers do neutrophils that exist in colorectal cancer metastases express and how do these support their function in cancer progression compared with in health? One important consideration is that neutrophils are important for normal immunity to fight off disease and by specifically targeting tumour promoting neutrophils future therapies may negotiate difficulties with innate immunity.In this proposal I will address in detail which patients have high numbers of neutrophils associated with metastases by subtyping patients according to their disease biology using sequencing of molecular factors produced by the tumours. Using exciting new technologies that have been developed by an industry partner, Nanostring, I will then resolve the question of which types of neutrophils are present by performing in-depth spatially orientated assessment of neutrophil populations in liver tumours. Once I have identified neutrophil populations associated with aggressive disease biology I will use a state of the art mouse model of colorectal cancer metastasis I have developed in the laboratory to remove different populations of neutrophils within a living system most relevant to the human disease and assess the impact on the metastatic process using sophisticated microscopy of the mouse as metastases develop. These assessments will demonstrate the impact of these targeted approaches on the behaviour of neutrophils, interactions with immune and tumour cells and ultimately on mechanisms by which colorectal cancer spreads. Using the mouse model in a high throughput manner, where I test a number of molecular factors knocked out on neutrophils within the metastatic tumour system, I will be able to identify potential targets on neutrophils that could be used for therapy in future clinical trial.