Bladder cancer (BLCA) is a common and difficult-to-manage disease worldwide. Most common type of BLCA is urothelial carcinoma (UC). Fibrillin 2 (FBN2) was first discovered while studying Marfan syndrome, and its encoded products are associated with elastin fibres. To date, the role of FBN2 in BLCA remains unclear. The authors first downloaded data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). The patients were divided into high FBN2 expression and low FBN2 expression groups, and the survival curve, clinical characteristics, tumour microenvironment (TME), and immune cell differences were analysed between the two groups. Then, the differentially expressed genes (DEGs) were filtered, and functional enrichment for DEGs was performed. Finally, chemotherapy drug susceptibility analysis based on the high and low FBN2 groups was conducted. The authors found upregulated expression of FBN2 in BLCA and proved that FBN2 could be an independent prognostic factor for BLCA. TME analysis showed that the expression of FBN2 affects several aspects of the TME. The upregulated expression of FBN2 was associated with a high stromal score, which may lead to immunosuppression and be detrimental to immunotherapy. In addition, the authors found that NK cells resting, macrophage M0 infiltration, and other phenomena of immune cell infiltration appeared in the high expression group of FBN2. The high expression of FBN2 was related to the high sensitivity of some chemotherapy drugs. The authors systematically investigated the effects and mechanisms of FBN2 on BLCA and provided a new understanding of the role of FBN2 as a risk factor and TME influencer in BLCA.

中文翻译：

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膀胱癌FBN2的综合分析：危险因素和肿瘤微环境影响因素。

膀胱癌（BLCA）是世界范围内一种常见且难以治疗的疾病。最常见的 BLCA 类型是尿路上皮癌 (UC)。原纤维蛋白 2 (FBN2) 最初是在研究马凡综合征时发现的，其编码产物与弹性蛋白纤维有关。迄今为止，FBN2 在 BLCA 中的作用仍不清楚。作者首先从癌症基因组图谱 (TCGA) 和基因表达综合 (GEO) 下载数据。将患者分为FBN2高表达组和FBN2低表达组，分析两组患者的生存曲线、临床特征、肿瘤微环境（TME）和免疫细胞差异。然后，筛选差异表达基因（DEG），并对DEG进行功能富集。最后根据FBN2高、低组进行化疗药物敏感性分析。作者发现 BLCA 中 FBN2 表达上调，证明 FBN2 可能是 BLCA 的独立预后因素。TME分析表明FBN2的表达影响TME的多个方面。FBN2表达上调与高基质评分相关，这可能导致免疫抑制并对免疫治疗不利。此外，作者发现FBN2高表达组出现NK细胞静息、巨噬细胞M0浸润等免疫细胞浸润现象。FBN2的高表达与某些化疗药物的高敏感性有关。作者系统地研究了 FBN2 对 BLCA 的影响和机制，并对 FBN2 作为 BLCA 风险因素和 TME 影响因素的作用提供了新的认识。