Defining the role of the IgE-Fc epsilon receptor-1 immune surveillance axis in human cutaneous squamous cell carcinoma

研究背景：皮肤癌是人类最常见的癌症，皮肤鳞状细胞癌（cSCC）是第二常见的形式。cSCC主要由来自太阳暴露的紫外线辐射（UV）引起。在英国，每年至少有30，000例新病例发生，cSCC在免疫系统受损的患者中更常见。大多数cSCC都是手术治疗，但这可能会导致严重的问题，因为70%的cSCC位于美容敏感的头部和颈部位置，许多患者会发展出不止一个cSCC。晚期（转移性）cSCC扩散到淋巴结或内脏器官的发生率高达5%，目前的治疗效果较差，尽管最近的证据表明免疫治疗可能有希望。尽管如此，晚期cSCC仍然是一个重要的未满足的临床需求领域。在以前的研究中，我们发现cSCC中的遗传损伤比几乎任何其他癌症都高（可能是因为紫外线非常突变），并且在转移风险高的cSCC中，免疫基因特别突变，包括免疫基因Fc γ受体1（FCER 1）。我们发现，在对皮肤损伤（例如紫外线或化学品）的反应中，细胞释放抗体IgE，这导致含有蛋白质FceR 1的免疫细胞数量增加，这些免疫细胞用于保护身体免受皮肤癌的侵害。这种相互作用会影响免疫系统如何抑制小鼠皮肤癌：当IgE-FceRI相互作用减少时，皮肤癌风险增加。目的和方法：我们将研究IgE-FceRI相互作用如何控制cSCC的发展，以及这是否会影响转移的风险。我们将首先通过使用一种技术对新鲜肿瘤进行详细分析来检查哪些cSCC免疫细胞携带受体，该技术使我们能够识别存在的免疫细胞的确切类型以及它们是否携带FceRI（FceRI+）。我们将特别寻找低风险，高风险和转移性cSCC之间的差异。然后，我们将研究FceRI+免疫细胞在肿瘤中的精确位置，因为这可能提供有关其在cSCC中作用的进一步信息。我们将使用一种技术，在这种技术中，整个肿瘤切片被检查，细胞的确切位置可以被识别。这些结果将在使用FceRI+细胞抗体的更大系列cSCC中得到证实。我们将询问FceRI+细胞的存在和位置是否与转移风险相关，以及FceRI是否是风险增加的标志物。我们还将在这一更大系列的样本中检测FceRI基因的活性，并将再次研究这是否与转移的cSCC相关。在最后一系列实验中，我们将研究改变IgE-FceRI相互作用是否对cSCC生长有影响。我们将使用我们以前从患者中培养的cSCC细胞系以及小的新鲜cSCC样本，并将添加阻断或增加IgE-FceRI相互作用的药物，并观察这如何改变癌细胞的行为。最后，我们将人类cSCC样本移植到小鼠体内，通过插入一小块肿瘤或将肿瘤细胞悬浮液注射到小鼠皮肤中。阻断和刺激药物将再次用于检查对cSCC生长的影响，并将详细分析所得肿瘤中免疫细胞和FceRI的存在。潜在的应用和益处：总之，我们以前的研究表明IgE-FceRI在cSCC中发挥重要作用。我们将研究cSCC中FceRI表达细胞的存在和位置，以及这是否会影响肿瘤进展的风险。我们还将研究阻断或刺激这种相互作用是否对肿瘤生长有影响。最终，这项研究将提高我们对cSCC如何发展的理解。它也可以提供重要的标志物，用于预测哪些cSCC具有高转移风险。最后，它也可能为开发适用于晚期cSCC的新治疗方法提供重要方向。

Context of research:Skin cancer is the most common human cancer and cutaneous squamous cell carcinoma (cSCC) is the second most common form. cSCC is caused mainly by ultraviolet radiation (UV) from sun exposure. At least 30,000 new cases occur every year in the UK and cSCC is more common in patients with compromised immune systems. Most cSCC are treated surgically, but this may cause significant problems, given that 70% are on cosmetically sensitive head and neck locations and many patients develop more than one cSCC. Advanced (metastatic) cSCC with spread to lymph nodes or internal organs occurs in up to 5% and current treatments have poor responses, although recent evidence suggests immunotherapy may be promising. Nonetheless, advanced cSCC remains an area of important unmet clinical need. In previous research, we showed that genetic damage is higher in cSCC than in almost any other cancer (probably because UV is very mutating) and also that immune genes are particularly mutated in cSCC at high risk of metastasis, including the immune gene Fc epsilon receptor 1 (FCER1). We showed that in response to skin damage (e.g. UV or chemicals), the antibody IgE is released by cells and this results in increased numbers of immune cells containing the protein FceR1 which act to defend the body against skin cancer. This interaction affects how the immune system suppresses skin cancer in mice: when the IgE-FceRI interaction is reduced, skin cancer risk is increased.Aims and methods:We will investigate how IgE-FceRI interactions control cSCC development and whether this affects risk of metastasis. We will first examine which cSCC immune cells carry the receptor by a detailed analysis of fresh tumours using a technique which allows us to identify the exact type of immune cells present and whether or not they carry FceRI (FceRI+). We will particularly look for differences between low-risk, high-risk and metastatic cSCC. We will then investigate the precise location of FceRI+ immune cells in tumours as this may provide further information on their role in cSCC. We will use a technique in which whole tumour sections are examined and the exact location of cells can be identified. These results will be confirmed in a larger series of cSCC using antibodies to FceRI+ cells. We will ask whether the presence and location of FceRI+ cells are associated with metastatic risk and whether FceRI is a marker for increased risk. We will also test for the activity of the FceRI gene in this larger series of samples and will again investigate if this is associated with cSCC that metastasise. In the final series of experiments we will investigate whether altering IgE-FceRI interactions has an effect on cSCC growth. We will use cSCC cell lines that we have previously grown from patients and also small fresh cSCC samples and will add drugs that either block or increase IgE-FceRI interactions and see how this changes the behaviour of cancer cells. Finally, we will transplant human cSCC samples into mice, either by inserting a small piece of tumour or injecting suspensions of tumour cells into the mouse skin. Blocking and stimulating drugs will again be used to examine effects on cSCC growth and the resulting tumours will be analysed in detail for the presence of the immune cells and FceRI. Potential applications and benefits:In summary, our previous research has suggested an important role for IgE-FceRI in cSCC. We will investigate the presence and location of FceRI-expressing cells in cSCC and whether this influences the risk of tumours progressing. We will also examine whether blocking or stimulating this interaction has an effect on tumour growth. Ultimately, this research will improve our understanding of how cSCCs develop. It may also provide important markers for predicting which cSCC are at high risk of metastasis. Finally, it may also provide important directions for developing new treatments suitable for advanced cSCC.