Liu Donghui, Wang Xuyao, Shi Enhong, Wang Liru, Nie Minghao, Li Long, Jiang Qingxin, Kong Pengyu, Shi Shuai, Wang Chao, Yan Sen, Qin Zhihui, Zhao Shuang
Department of Oncology, Heilongjiang Provincial Hospital, Harbin, China.
Department of Pharmacy, Harbin Second Hospital, Harbin, China.
Front Genet. 2021 Jul 16;12:699910. doi: 10.3389/fgene.2021.699910. eCollection 2021.
The SET and MYND domain-containing (SMYD) gene family comprises a set of genes encoding lysine methyltransferases. This study aimed to clarify the relationship between the expression levels of SMYD family members and the prognosis and immune infiltration of malignant tumors of the digestive system.
The Oncomine, Ualcan, Kaplan-Meier Plotter, cBioPortal, Metascape, and TIMER databases and tools were used to analyze the correlation of SMYD family mRNA expression, clinical stage, TP53 mutation status, prognostic value, gene mutation, and immune infiltration in patients with esophageal carcinoma (ESCA), liver hepatocellular carcinoma (LIHC), and stomach adenocarcinoma (STAD).
In ESCA, the mRNA expression of SMYD2/3/4/5 was significantly correlated with the incidence rate, that of SMYD2/3 with the clinical stage, that of SMYD2/3/4/5 with TP53 mutation status, that of SMYD2/4/5 with overall survival (OS), and that of SMYD1/2/3/4 with relapse-free survival (RFS). In LIHC, the mRNA expression of SMYD1/2/3/4/5 was significantly correlated with the incidence rate, that of SMYD2/4/5 with the clinical stage, that of SMYD3/5 with TP53 mutation status, that of SMYD2/3/4/5 with OS, and that of SMYD3/5 with RFS. In STAD, the mRNA expression of SMYD2/3/4/5 was significantly correlated with the incidence rate, that of SMYD1/4 with the clinical stage, that of SMYD1/2/3/5 with TP53 mutation status, that of SMYD1/3/4 with OS, and that of SMYD1/3 with RFS. Furthermore, the function of SMYD family mutation-related genes in ESCA, LIHC, and STAD patients was mainly related to pathways, such as mitochondrial gene expression, mitochondrial matrix, and mitochondrial translation. The expression of SMYD family genes was significantly correlated with the infiltration of six immune cell types and eight types of immune check sites.
SMYD family genes are differentially expressed and frequently mutated in malignant tumors of the digestive system (ESCA, LIHC, and gastric cancer). They are potential markers for prognostic prediction and have important significance in immunity and targeted therapy.
含SET和MYND结构域（SMYD）基因家族由一组编码赖氨酸甲基转移酶的基因组成。本研究旨在阐明SMYD家族成员的表达水平与消化系统恶性肿瘤的预后及免疫浸润之间的关系。
使用Oncomine、Ualcan、Kaplan-Meier Plotter、cBioPortal、Metascape和TIMER数据库及工具，分析食管癌（ESCA）、肝细胞肝癌（LIHC）和胃腺癌（STAD）患者中SMYD家族mRNA表达、临床分期、TP53突变状态、预后价值、基因突变及免疫浸润的相关性。
在ESCA中，SMYD2/3/4/5的mRNA表达与发病率显著相关，SMYD2/3与临床分期相关，SMYD2/3/4/5与TP53突变状态相关，SMYD2/4/5与总生存期（OS）相关，SMYD1/2/3/4与无复发生存期（RFS）相关。在LIHC中，SMYD1/2/3/4/5的mRNA表达与发病率显著相关，SMYD2/4/5与临床分期相关，SMYD3/5与TP53突变状态相关，SMYD2/3/4/5与OS相关，SMYD3/5与RFS相关。在STAD中，SMYD2/3/4/5的mRNA表达与发病率显著相关，SMYD1/4与临床分期相关，SMYD1/2/3/5与TP53突变状态相关，SMYD1/3/4与OS相关，SMYD1/3与RFS相关。此外，ESCA、LIHC和STAD患者中SMYD家族突变相关基因的功能主要与线粒体基因表达、线粒体基质和线粒体翻译等途径有关。SMYD家族基因的表达与六种免疫细胞类型和八种免疫检查点的浸润显著相关。
SMYD家族基因在消化系统恶性肿瘤（ESCA、LIHC和胃癌）中存在差异表达且频繁突变。它们是预后预测的潜在标志物，在免疫和靶向治疗中具有重要意义。
