本研究旨在鉴定与头颈鳞状细胞癌（HNSCC）中免疫细胞浸润程度相关的基因，探索其新的生物学功能，并评估其在HNSCC的诊断和预后价值。使用癌症基因组图谱（TCGA）的转录组数据集筛选肿瘤和正常组织之间的差异表达基因，随后进行加权相关网络分析（WGCNA）以识别与免疫相关的单元。进行差异基因表达、免疫细胞浸润和生存分析以筛选关键基因。在Oncomine和基因表达Omnibus（GEO）数据集以及免疫组织化学（IHC）中验证这些关键基因的表达。在HNSCC中有1869个基因被显著上调，有1578个基因被显著下调。WGCNA表明，棕色模块与最多的免疫相关基因相关。蛋白互作网络分析表明，PPL、SCEL、KRT4、KRT24、KRT78、KRT13、SPRR3、TGM3、CRCT1和CRNN是棕色模块中的关键成分。此外，HNSCC中KRT4、KRT78、KRT13和SPRR3的表达水平与CD8+ T细胞和巨噬细胞的浸润水平相关。生存分析揭示了HNSCC中KRT78、KRT13和SPRR3的表达与总生存期（OS）相关。IHC实验表明，与正常组织相比，HNSCC中KRT13（p=0.042）、KRT78（p＜0.001）和SPRR3（p=0.022）的蛋白表达水平显著降低。分析GSE65858和GSE41613数据集表明，低表达KRT78（p=0.0086和p=0.005）和SPRR3（p=0.017和p=0.02）与更糟的OS有关。我们的研究结果表明，KRT4、KRT78、KRT13和SPRR3与HNSCC的发生和发展相关。尤其是，KRT78和SPRR3可能作为HNSCC的诊断和预后生物标志物。© 2023 The Authors. Cancer Reports published by Wiley Periodicals LLC.

This study aimed to identify genes related to the degree of immune cell infiltration in head and neck squamous cell carcinoma (HNSCC), explore their new biological functions, and evaluate their diagnostic and prognostic value in HNSCC.Transcriptomic data from The Cancer Genome Atlas (TCGA) HNSCC dataset was used to screen differentially expressed genes between tumors and normal tissues, followed by weighted correlation network analysis (WGCNA) to identify immune-related modules. Differential gene expression, immune cell infiltration, and survival analyses were performed to screen key genes. The expression of these key genes was validated in Oncomine and gene expression omnibus (GEO) datasets and by immunohistochemistry (IHC).1869 and 1578 genes were significantly upregulated and downregulated in HNSCC. WGCNA showed that the brown module was associated with the most significant number of immune-related genes. PPI network analysis demonstrated that PPL, SCEL, KRT4, KRT24, KRT78, KRT13, SPRR3, TGM3, CRCT1, and CRNN were key components in the brown module. Furthermore, the expression levels of KRT4, KRT78, KRT13, and SPRR3 in HNSCC correlated with infiltration levels of CD8+ T cells and macrophages. Survival analyses revealed that the expression of KRT78, KRT13, and SPRR3 in HNSCC correlated with overall survival (OS). The IHC assay indicated that KRT13 (p = .042), KRT78 (p < .001), and SPRR3 (p = .022) protein expression levels in HNSCC were significantly lower than in normal tissues. Analysis of GSE65858 and GSE41613 datasets showed that a worse OS was associated with low expression of KRT78 (p = .0086, and p = .005) and SPRR3 (p = .017, and p = .02).Our findings suggest that KRT4, KRT78, KRT13, and SPRR3 are related to the occurrence and development of HNSCC. Importantly, KRT78 and SPRR3 might serve as diagnostic and prognostic biomarkers of HNSCC.© 2023 The Authors. Cancer Reports published by Wiley Periodicals LLC.