摘要目的:探讨补体C3a受体1(C3AR1)在脑胶质瘤中的表达情况及其促进脑胶质瘤恶性进展的机制。方法:(1)从癌症基因组图谱(TCGA)数据库和中国脑胶质瘤图谱(CGGA)数据库中分别获取607例和656例脑胶质瘤患者的临床信息及其肿瘤组织中 C3AR1 mRNA数据，分析不同WHO分级胶质瘤间 C3AR1 mRNA的表达差异，并应用GEPIA平台比较TCGA数据库中 C3AR1 mRNA低表达组患者与 C3AR1 mRNA高表达组患者间总体生存期、无病生存期的差异，使用DAVID数据库进行C3AR1相关显著差异表达基因的基因本体(GO)功能和京都基因与基因组百科全书(KEGG)通路富集分析，使用TIMER网站在线分析 C3AR1 mRNA表达与免疫细胞浸润程度的相关性。(2)收集新乡医学院第一附属医院神经外科自2019年1月至2021年9月手术切除的3例非肿瘤脑组织与9例脑胶质瘤组织标本，应用Western blotting实验检测C3AR1蛋白的表达。(3)体外培养U87、U251细胞并分别分为对照组和 C3AR1敲低组(通过慢病毒转染方式敲低 C3AR1)，采用CCK-8实验、平板克隆形成实验和Transwell实验检测2组细胞的增殖率、集落形成个数、穿膜细胞数量，采用Western blotting实验检测核因子-κB(NF-κB)信号通路相关蛋白的表达。 结果:(1)TCGA数据库中，WHO分级Ⅱ、Ⅲ级、Ⅳ级肿瘤组织中 C3AR1 mRNA的表达依次增加，差异均有统计学意义( P<0.05)。CGGA数据库中，WHO分级Ⅳ级肿瘤组织中 C3AR1 mRNA的表达明显高于Ⅱ级、Ⅲ级，差异均有统计学意义( P<0.05)。GEPIA分析显示， C3AR1 mRNA低表达组患者的总体生存期、无病生存期均明显高于 C3AR1 mRNA高表达组，差异均有统计学意义( P<0.05)。GO功能及KEGG通路富集分析显示，与C3AR1相关的显著差异表达基因更多地富集在钙离子稳态、膜结构阀门、质子跨膜转运蛋白活性、趋化因子信号通路以及NF-κB信号通路等生物过程和信号通路中。TIMER分析显示，胶质母细胞瘤及低级别脑胶质瘤中 C3AR1 mRNA表达均与B细胞、CD4 + T细胞、嗜中性粒细胞、巨噬细胞和树突状细胞的浸润程度呈正相关关系( P<0.05)，胶质母细胞瘤中 C3AR1 mRNA表达与CD8 + T细胞浸润程度呈负相关关系( P<0.05)。(2)脑胶质瘤组织标本中C3AR1蛋白的表达明显高于非肿瘤脑组织标本，差异有统计学意义( P<0.05)。(3) C3AR1敲低组细胞的增殖率、集落形成个数、穿膜细胞数量以及NF-κB、磷酸化(p)-NF-κB、p-NF-κB抑制蛋白(IκB)α、p-IκB激酶(IKK)α、N-钙黏蛋白的表达均明显低于对照组，E-钙黏蛋白的表达明显高于对照组，差异均有统计学意义( P<0.05)。 结论:C3AR1在脑胶质瘤中呈高表达，并通过NF-κB信号通路调控其恶性进展。

abstractsObjective:To investigate the complement C3a receptor 1 (C3AR1) expression in glioma and its mechanism in progressing malignancy.Methods:(1) The C3AR1 mRNA expression data and clinical information were obtained in 607 glioma patients from The Cancer Genome Atlas (TCGA) database and 656 glioma patients from Chinese Glioma Genome Atlas (CGGA) database; the differences in C3AR1 mRNA expression were analyzed among gliomas with different World Health Organization (WHO) grading. The overall survival and disease-free survival were compared between high and low C3AR1 mRNA expression patients obtained from TCGA database by Gene expression profiling interactive analysis (GEPIA). Gene body (GO) function analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of C3AR1 related differentially expressed genes were performed by DAVID database. Correlation of C3AR1 mRNA expression with immune cell infiltration was analyzed using TIMER online website. (2) The brain tissues from 3 non-tumor patients and 9 glioma patients surgically resected in Department of Neurosurgery, First Affiliated Hospital of Xinxiang Medical University from January 2019 to September 2021 were collected; the C3AR1 protein expression was detected by Western blotting. (3) The in vitro cultured U87 and U251 cells were divided into negative control group and C3AR1 knockdown group ( C3AR1 being knocked down by lentivirus transfection); and CCK-8 assay, plate cloning assay and Transwell assay were used to detect the proliferation rate, number of colony formation and number of membrane penetrating cells. Western blotting was used to detect the nuclear factor-κB (NF-κB) signaling pathway protein expressions. Results:(1) In TCGA database, the C3AR1 mRNA expression in gliomas of WHO grading II, grading III and grading IV increased sequentially, with significant differences ( P<0.05). In CGGA database, the C3AR1 mRNA expression in glioma of WHO grading IV was statistically higher than that in gliomas of WHO grading II and grading III ( P<0.05). GEPIA showed that the overall survival and disease-free survival in the low C3AR1 mRNA expression group were statistically higher than those in the high C3AR1 mRNA expression group ( P<0.05). GO function analysis and KEGG pathway enrichment analysis revealed that C3AR1 related differentially expressed genes were more enriched in such biological processes and signaling pathways as calcium homeostasis, membrane structural valves, proton transmembrane transporter protein activity, chemokine signaling pathway and NF-κB signaling pathway. TIMER showed that C3AR1 mRNA expression in glioblastoma and low-grade glioma was positively correlated with infiltration degrees of B cells, CD4 + T cells, neutrophils, macrophages and dendritic cells, and C3AR1 mRNA expression in glioblastoma was negatively correlated with infiltration degree of CD8 + T cells ( P<0.05). (2) C3AR1 protein expression in glioma tissues was significantly higher than that in non-tumor tissues. (3) Compared with the negative control group, the C3AR1 knockdown group group had significantly lower proliferation rate, smaller numbers of colony formation and membrane penetrating cells, and lower expressions of NF-κB, phosphorylated (p)-NF-κB, p-NF-κB inhibitory protein (IκB)α, p-I-κB kinase (IKK)α and N-cadherin, and significantly higher E-cadherin expression. Conclusion:C3AR1 is highly expressed in glioma and progresses malignancy through NF-κB signaling pathway.