Characterising the surfaceome of hypoxic myeloid cells infiltrating the tumour microenvironment.

肿瘤相关巨噬细胞（tam）是肿瘤微环境中最丰富的群体之一，可以促进癌症的进展。巨噬细胞的行为受到环境刺激的影响，包括缺氧，从而进一步促进治疗抵抗和癌症复发。虽然人们对靶向tam来提高抗肿瘤效果很感兴趣，但在开发治疗方法之前，需要进一步研究以确定缺氧tam的标记物。一个硅表面体数据集（Bausch-Fluck et al.）揭示了超过100个编码细胞表面分子的基因在人单核细胞中被二甲氧基草酸甘氨酸（DMOG）（一种模拟缺氧的物质）处理后上调。为了确定候选TAM标记，我们根据已知的表达谱对基因进行筛选，并进行文献综述，筛选出9个感兴趣的基因进行进一步探索。单核细胞被招募到肿瘤微环境中，在那里它们分化成tam。其中，TNFRSF1B、TREM1、HCAR3和PLAUR在缺氧的人单核细胞源性巨噬细胞（MDMs）中表达升高。然后用流式细胞术在差异处理的MDMs中评估这些基因的产物。细胞表面CD87（由PLAUR编码）、TREM1和TNFR2 （TNFRSF1B）在缺氧情况下上调，在促炎细胞因子偏斜的MDMs中也上调，代表了相关的缺氧敏感标志物，值得进一步研究。为了研究这些标志物在更多临床相关模型中的表达，我们在使用癌细胞系条件培养基（CM）产生的tam样巨噬细胞上评估了它们的表达。来自可能组成性表达低氧相关蛋白的细胞系的CM在常氧条件下显著上调候选标记。为了阐明调节其表达的因素，将通过ELISA、PCR和超离心评估癌细胞释放的细胞因子、趋化因子和外泌体。这些标记物将通过免疫组织化学在原发性人类肿瘤样本中进一步评估。在随后的验证之后，将获得或生成能够调节受体的单克隆抗体，以探索其调节巨噬细胞行为的能力。

Tumour-associated macrophages (TAMs) are one of the most abundant populations in the tumour microenvironment and can contribute to cancer progression. The behaviour of macrophages is influenced by environmental stimuli, including hypoxia (oxygen deprivation), to further promote therapy resistance and cancer relapse. Whilst there is an interest in targeting TAMs to improve anti-tumour efforts, further study is needed to identify markers for hypoxic TAMs before developing therapies. An in silico surfaceome dataset (Bausch-Fluck et al.) revealed over 100 genes encoding cell surface molecules were upregulated in human monocytes treated with dimethyloxalylglycine (DMOG), a hypoxia mimetic. To identify candidate TAM markers, genes were then filtered based on their known expression profile and a literature review was conducted to identify 9 genes of interest to explore further. Monocytes are recruited to the tumour microenvironment where they differentiate into TAMs. Of these 9, TNFRSF1B, TREM1, HCAR3, and PLAUR expression was increased in hypoxic human monocyte-derived macrophages (MDMs). The product of these genes was then assessed by flow cytometry in differentially treated MDMs. Cell surface CD87 (encoded by PLAUR), TREM1, and TNFR2 (TNFRSF1B) was upregulated in the presence of hypoxia and also in MDMs skewed with pro-inflammatory cytokines, representing relevant hypoxia-sensitive markers to investigate further. To investigate the expression of these markers in more clinically relevant models, their expression was assessed on TAM-like macrophages generated using cancer cell line conditioned media (CM). CM from cell lines that may constitutively express hypoxia-related proteins considerably upregulated the candidate markers at normoxia. To elucidate the factors regulating their expression, cytokines, chemokines, and exosomes released by cancer cells will be assessed by ELISA, PCR, and ultracentrifugation. These markers will be further assessed by immunohistochemistry in primary human tumour samples. Following subsequent validation, monoclonal antibodies capable of modulating the receptor will be sourced or generated to explore their ability to modulate macrophage behaviour.