DataSheet_1_Identification and validation of a novel phagocytosis regulators-related signature with potential prognostic and immunotherapeutic value in patients with lung adenocarcinoma.docx

BackgroundLung adenocarcinoma (LUAD) is a malignant tumor that seriously affects the prognosis of patients. Tumor-associated macrophages (TAMs) play a vital role in the tumor microenvironment and can be used as a potential target for tumor therapy, and phagocytosis regulators (PRs) are particularly important in this process. However, the PRs-related signature that can predict the potential prognostic and immunotherapeutic value in patients with LUAD has not been discovered.
MethodsIn this study, we mainly analyzed the effect of phagocytosis regulators on the prognosis of LUAD, and based on multiple screening analyses including differential analysis, univariate Cox analysis, and Lasso analysis, we constructed a prognostic risk model consisting of five genes. To verify the stability of the model, survival analysis and ROC curve verification were carried out through multiple data sets. In addition, we also combined many factors, such as immune infiltrating cells, clinical grouping characteristics, immune examination sites, pro-inflammatory factors, and other factors as well as in vitro cell experiments and clinical tissue samples for further validation analysis.
ResultsAfter identifying 29 differentially expressed PRs in LUAD samples, we further constructed a prognostic model consisting of five prognostic signatures (FURIN, KIF23, SASH3, GNPNAT1, and ITGAL). Further survival analysis tests, ROC verification, as well as univariate and multivariate Cox regression analysis showed that the risk score of the model could well predict the prognosis of LUAD patients and could be used as an independent prognostic factor. In addition, we further found that these phagocytic regulators-related signatures were closely related to the immune microenvironment and immunotherapy in LUAD patients, and could well predict the efficacy of immunotherapy in patients. In vitro cell experiments and Immunohistochemistry of clinical tissues showed that the expressions of FURIN, KIF23, SASH3, GNPNAT1 and ITGAL in normal lung cells/tissues and LUAD cells/tissues were consistent with bioinformatics results, and 3 of them had significant differences.
ConclusionOur study identified a novel PRs-related signature that has potential application value in predicting the prognosis of LUAD patients and predicting the efficacy of immunotherapy. This provides a new basis for the prognosis assessment of LUAD patients and provides a novel target for immunotherapy of LUAD patients.

背景
肺腺癌（Lung adenocarcinoma, LUAD）是一类严重影响患者预后的恶性肿瘤。肿瘤相关巨噬细胞（Tumor-associated macrophages, TAMs）在肿瘤微环境中发挥至关重要的调控作用，可作为肿瘤治疗的潜在靶点；而吞噬调节因子（phagocytosis regulators, PRs）在该过程中尤为关键。然而，目前尚未发现可用于预测肺腺癌患者潜在预后与免疫治疗价值的吞噬调节因子相关特征基因集。
方法
本研究聚焦于吞噬调节因子对肺腺癌患者预后的影响，通过差异表达分析、单因素Cox回归分析（univariate Cox analysis）、Lasso回归分析（Lasso analysis）等多重筛选策略，构建了由5个基因组成的预后风险模型。为验证该模型的稳定性，研究团队依托多组数据集开展了生存分析与受试者工作特征曲线（Receiver Operating Characteristic curve, ROC）验证。此外，本研究还结合免疫浸润细胞、临床分组特征、免疫检测位点、促炎因子等多项因素，并联合体外细胞实验与临床组织样本开展进一步验证分析。
结果
研究首先在肺腺癌样本中鉴定出29个差异表达的吞噬调节因子，进而构建了包含5个预后特征基因（FURIN、KIF23、SASH3、GNPNAT1及ITGAL）的预后模型。进一步的生存分析、ROC曲线验证以及单因素、多因素Cox回归分析结果显示，该模型的风险评分可有效预测肺腺癌患者的预后，且可作为独立的预后因素。此外，研究还发现这些与吞噬调节因子相关的特征基因与肺腺癌患者的免疫微环境及免疫治疗密切相关，能够较好地预测患者的免疫治疗疗效。体外细胞实验与临床组织免疫组化结果表明，FURIN、KIF23、SASH3、GNPNAT1及ITGAL在正常肺细胞/组织与肺腺癌细胞/组织中的表达趋势与生物信息学分析结果一致，其中3个基因的表达差异具有统计学意义。
结论
本研究鉴定出一种全新的吞噬调节因子相关特征基因集，其在预测肺腺癌患者预后与免疫治疗疗效方面具备潜在应用价值。该研究为肺腺癌患者的预后评估提供了新的理论依据，同时也为肺腺癌患者的免疫治疗提供了新型潜在靶点。