CD5分子样物（CD5L）在脂质代谢和免疫调节中起重要作用。本研究旨在探讨CD5L在肝肝细胞癌（LIHC）中的作用。我们分析了基于癌症基因组图谱和基因表达 omnibus 数据库的 CD5L mRNA 表达及其潜在预后价值。采用免疫组化分析研究 LIHC 组织中的 CD5L 水平。采用酶联免疫吸附测定法检测 LIHC 患者血清中的 CD5L 水平。使用细胞计数试剂盒-8（CCK-8）试剂探究 CD5L 处理对 HepG2 和 QSG-7701 细胞增殖的影响。基于 LinkedOmics 挖掘与 CD5L 表达相关的基因。进行与 CD5L 相关的基因 的基因本体论和京都基因与基因组百科全书分析。使用肿瘤免疫估计资源（TIMER）2.0 分析 CD5L 与肿瘤免疫浸润之间的相关性。与非肿瘤对照组组织相比，CD5L mRNA 和蛋白水平在 LIHC 肿瘤组织中显著降低。此外，LIHC 患者血清中的 CD5L 水平显著低于健康受试者。基因表达分析交互式分析筛选 2 和 Kaplan-Meier 生存分析表明，高 CD5L 表达与 LIHC 患者良好的总体生存率相关，除了患有肝炎病毒的 LIHC 患者。 CCK-8 结果表明，CD5L 治疗显著抑制了 HepG2 细胞的浓度依赖性增殖，并且 CD5L 治疗对非肿瘤肝细胞系 QSG-7701 的增殖没有影响。 CD5L 关联基因富集在免疫应答生物过程中，CD5L 表达水平与 CD8+ T 细胞和 M1巨噬细胞的免疫浸润呈正相关，而与 CD4+ T 细胞和 M0巨噬细胞的浸润呈负相关。外源性 CD5L 抑制肝细胞癌细胞增殖。 CD5L 可作为一种预后标志物的角色。版权所有©2023年中国医学会，由 Wolters Kluwer 公司根据 CC-BY-NC-ND 许可发布。

CD5 molecular-like (CD5L) plays an important role in lipid metabolism and immune regulation. This study aimed to investigate the roles of CD5L on liver hepatocellular carcinoma (LIHC).We analyzed the CD5L mRNA expression and its potential prognostic value based on The Cancer Genome Atlas and Gene Expression Omnibus databases. Immunohistochemical analysis was used to investigate the CD5L levels in LIHC tissues. Serum CD5L levels in LIHC were detected by enzyme-linked immunosorbent assay. Cell Counting Kit-8 (CCK-8) assay was used to investigate the effect of CD5L treatment on HepG2 and QSG-7701 cell proliferation. CD5L expression correlated genes were exhumed based on the LinkedOmics. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses for CD5L associated genes were performed. The correlation between CD5L and tumor immune infiltration was analyzed by using Tumor Immune Estimation Resource (TIMER) 2.0.CD5L mRNA and protein levels were significantly decreased in LIHC tumor tissue compared with non-tumor control tissues. Moreover, serum CD5L levels were significantly lower in LIHC patients than that in healthy subjects. Gene Expression Profiling Interactive Analysis 2 and Kaplan-Meier plotter analysis showed that a high-CD5L expression was correlated with favorable overall survival in LIHC patients, except the LIHC patients with hepatitis virus. CCK-8 results showed that CD5L treatment significantly decreased HepG2 cell proliferation in a concentration-dependent manner, and CD5L treatment had no effect on the proliferation of non-tumor hepatocyte line QSG-7701. CD5L associated genes were enriched in the immune response biological process, and CD5L expression levels were positively correlated with the immune infiltrates of CD8+ T cell and M1 macrophage cells but negatively correlated with CD4+ T cells and M0 macrophage cell infiltration.Exogenous CD5L inhibits liver hepatocellular carcinoma cell proliferation. CD5L may act as a role of prognostic marker.Copyright © 2023 The Chinese Medical Association, produced by Wolters Kluwer, Inc. under the CC-BY-NC-ND license.