Yin Lei, Feng Shichun, Sun Yongqiang, Jiang Yasu, Tang Chong, Sun Dongwei
Department of General Surgery, Affiliated Hospital 2 of Nantong University, Nantong, China.
Department of General Surgery, Institute of General Surgery, Clinical Medical College, Yangzhou University, Northern Jiangsu People's Hospital, Yangzhou, China.
J Gastrointest Oncol. 2022 Oct;13(5):2234-2248. doi: 10.21037/jgo-22-962.
N6-methyladenosine (m6A) is the most abundant form of methylation modification in eukaryotic cell messenger RNA (mRNA). However, the role of m6A in gastric cancer (GC), which is one of the most common gastrointestinal malignancies, is unclear. In this study, m6A-relevant mRNA signatures and risk scores were determined to predict the prognosis of GC.
The expression profiles and clinical information of 367 patients were downloaded from The Cancer Genome Atlas (TCGA). Cluster analysis and univariate Cox analysis were performed to identify the regulatory factors of RNA methylation associated with GC prognosis. A co-expression network was constructed using the WGCNA package in R. The correlations between module eigengenes and clinical traits were then calculated to identify the relevant modules. We used univariate Cox analysis to screen for genes that are significantly associated with prognosis in the module. We identified hub genes by least absolute shrinkage and selection operator (LASSO) and multivariate analysis and developed a Cox prognostic model. Finally, the hub gene expression values weighted by the coefficients from the LASSO regression were applied to generate a risk score for each patient, and receiver operating characteristic (ROC) and Kaplan-Meier curves were used to assess the prognostic capacity of the risk scores. The asporin () gene in GC cell lines was verified via quantitative polymerase chain reaction (qPCR) and Western blot. Moreover, 5-ethynyl-2'-deoxyuridine (EdU) and transwell assays were applied to evaluate the effects of the proliferation, migration, and invasion abilities in GC cells after ASPN knockdown. Western blot verified the effects of on the phosphoinositide 3-kinase (PI3K)/serine/threonine kinase (AKT)/mechanistic target of rapamycin kinase (mTOR) pathway and epithelial-mesenchymal transition (EMT) pathway-related gene expression.
Our results indicated that and were hub genes affecting the prognosis of GC patients. Besides, we found that expression was upregulated in GC cells. The knockdown of expression suppressed GC cell proliferation, migration, and invasion by deactivating the PI3K/AKT/mTOR and EMT pathways, respectively.
Our findings indicated that participates in the biological process of GC as an oncogene and may be a promising biomarker in GC.
N6-甲基腺苷（m6A）是真核细胞信使核糖核酸（mRNA）中最丰富的甲基化修饰形式。然而，m6A在胃癌（GC）（最常见的胃肠道恶性肿瘤之一）中的作用尚不清楚。在本研究中，确定了与m6A相关的mRNA特征和风险评分以预测GC的预后。
从癌症基因组图谱（TCGA）下载了367例患者的表达谱和临床信息。进行聚类分析和单变量Cox分析以鉴定与GC预后相关的RNA甲基化调控因子。使用R中的WGCNA包构建共表达网络。然后计算模块特征基因与临床特征之间的相关性以鉴定相关模块。我们使用单变量Cox分析筛选模块中与预后显著相关的基因。我们通过最小绝对收缩和选择算子（LASSO）和多变量分析鉴定枢纽基因并建立Cox预后模型。最后，将LASSO回归系数加权的枢纽基因表达值应用于为每位患者生成风险评分，并使用受试者工作特征（ROC）和Kaplan-Meier曲线评估风险评分的预后能力。通过定量聚合酶链反应（qPCR）和蛋白质免疫印迹法验证GC细胞系中的阿spor蛋白（）基因。此外，应用5-乙炔基-2'-脱氧尿苷（EdU）和Transwell试验评估ASPN敲低后对GC细胞增殖、迁移和侵袭能力的影响。蛋白质免疫印迹法验证了对磷脂酰肌醇3激酶（PI3K）/丝氨酸/苏氨酸激酶（AKT）/雷帕霉素激酶机制靶点（mTOR）途径和上皮-间质转化（EMT）途径相关基因表达的影响。
我们的结果表明，和是影响GC患者预后的枢纽基因。此外，我们发现GC细胞中表达上调。敲低表达分别通过使PI3K/AKT/mTOR和EMT途径失活来抑制GC细胞增殖、迁移和侵袭。
我们的研究结果表明，作为一种癌基因参与GC的生物学过程，并且可能是GC中有前景的生物标志物。
