Tumor Mutation Burden, Immune Cell Infiltration, and Construction of Immune-Related Genes Prognostic Model in Head and Neck Cancer.

Background: Head and neck squamous cell carcinoma (HNSCC) is the sixth most common malignancy worldwide, and the prognosis of HNSCC remains bleak. Numerous studies revealed that the tumor mutation burden (TMB) could predict the survival outcomes of a variety of tumors. Objectives: This study aimed to investigate the TMB and immune cell infiltration in these patients and construct an immune-related genes (IRGs) prognostic model. Methods: The expression data of 546 HNSCC patients were obtained from The Cancer Genome Atlas (TCGA) database. All patients were divided into high- and low- TMB groups, and the relationship between TMB and clinical relevance was further analyzed. The differentially expressed genes (DEGs) were identified using the R software package, limma. Functional enrichment analyses were conducted to identify the significantly enriched pathways between two groups. CIBERSORT algorithm was adopted to calculate the abundance of 22 leukocyte subtypes. The IRGs prognostic model was constructed via the multivariate Cox regression analysis. Results: Missense mutation and single nucleotide variants (SNV) were the most predominant mutation types in HNSCC. TP53, TTN, and FAT1 were the most frequently mutated genes. Patients with high TMB were observed with worse survival outcomes. The functional analysis of TMB associated DEGs showed that the identified DEGs mainly involved in spliceosome, RNA degradation, proteasome, and RNA polymerase pathways. We observed that macrophages, T cells CD8, and T cells CD4 memory were the most commonly infiltrated subtypes of immune cells in HNSCC. Finally, an IRGs prognostic model was constructed, and the AUC of the ROC curve was 0.635. Conclusions: Our results suggest that high TMB is associated with poor prognosis in HNSCC patients. The constructed model has potential prognostic value for the prognosis of these individuals, and it needs to be further validated in large-scale and prospective studies.

Jiang AM ，Ren MD ，Liu N ，Gao H ，Wang JJ ，Zheng XQ ，Fu X ，Liang X ，Ruan ZP ，Tian T ，Yao Y ... -  《International Journal of Medical Sciences》

The prognostic value of TMB and the relationship between TMB and immune infiltration in head and neck squamous cell carcinoma: A gene expression-based study.

Whether tumor mutation burden (TMB) affects prognosis and immune infiltration of tumor patients is controversial. We designed and conducted a multi-omics study with the aim of investigating the prognostic value of TMB and the relationship between TMB and immune infiltration in head and neck squamous cell carcinoma (HNSCC). TMB scores were calculated from the mutation data of 506 HNSCC samples from The Cancer Genome Atlas (TCGA), and the patients were divided into low- and high-TMB groups according to the TMB score quartiles. Differentially expressed genes (DEGs) between the low-TMB and high-TMB groups were identified. Immune cell infiltration and survival analyses were conducted between groups. High TMB in HNSCC patients was associated with a poor prognosis, large primary tumor size, advanced clinical stage and a human papillomavirus (HPV)-negative status. A total of 576 DEGs were identified, and gene set enrichment analysis (GSEA) revealed that the DEGs in the low-TMB group were enriched in immune-related pathways. Four hub genes were significantly associated with prognosis, and mutations in these genes affected immune infiltration. The estimated fractions of B memory cells and CD4+ memory resting cells were higher in the low-TMB group than in the high-TMB group, and B cell and CD4+T cell infiltration was positively correlated with prognosis in HNSCC patients. HNSCC patients with low TMB have better prognoses than those with high TMB, and TMB might affect B cell and CD4+T cell infiltration.

Zhang L ，Li B ，Peng Y ，Wu F ，Li Q ，Lin Z ，Xie S ，Xiao L ，Lin X ，Ou Z ，Cai T ，Rong H ，Fan S ，Li J ... -  《-》

Seven Immune-Related Genes' Prognostic Value and Correlation with Treatment Outcome in Head and Neck Squamous Cell Carcinoma.

Mu R ，Shen Y ，Guo C ，Zhang X ，Yang H ，Yang H ... -  《-》

Establishment and validation of immune microenvironmental gene signatures for predicting prognosis in patients with head and neck squamous cell carcinoma.

Tumor cells influencing the microenvironment are essential for restrained immunity in head and neck squamous cell carcinoma (HNSCC). There has been considerable progress in the research on monoclonal antibodies for antigen-specific immunotherapy that overcome immunosuppressive checkpoint receptor/ligand signaling in patients with HNSCC. However, alteration of immunogenicity and formation of neoantigens that lead to dysregulation and immunosuppression in the HNSCC microenvironment is not well-defined. The aim of this study was to quantify the Immune, Stromal, and ESTIMATE scores based on the gene matrix of patients with HNSCC reported in The Cancer Genome Atlas (TCGA). We examined the association of the Immune, Stromal, and ESTIMATE scores with the pathologic characteristics of patients with HNSCC, using weighted gene co-expression network (WGCNA) and protein-protein interaction (PPI) analyses, and selected 17 hub gene signatures from the key gene module that was mostly correlated to immunocyte infiltration. Gene functional enrichment showed that this key gene module was closely related to the regulation of immune cell activation and its relevant pathways. In the prognostic analysis, high expression of CD3E, SASH3, CD2, SIRPG, UBASH3A, IKZF1, SPN, IL10RA, SLA, and CD3G was significantly associated with a good prognosis. Consequently, these prognosis-related genes were validated via analysis of mRNA expression in tumor-infiltrating lymphocytes (TILs) and matched peripheral blood lymphocytes (PBLs) in ten patients with HNSCC, and the expression of these genes was significantly higher in TILs compared to that in PBLs. These findings provide a novel understanding of the tumor immune targets for improved therapeutic regimes in patients with HNSCC.

Wang J ，Tian Y ，Zhu G ，Li Z ，Wu Z ，Wei G ，Zhuang L ，Li Z ，Chen X ，Zhang X ，Zheng J ，Cai G ... -  《-》

Identification of Immune-Related Prognostic Biomarkers Associated with HPV-Positive Head and Neck Squamous Cell Carcinoma.

As a type of malignant tumor, head and neck squamous cell carcinoma (HNSCC) seriously threatens human health. This study is aimed at constructing a new, reliable prognostic model. The gene expression profile data of HNSCC patients were downloaded from the Gene Expression Omnibus and The Cancer Genome Atlas databases. The immune-related differentially expressed genes (IRDEGs) related to HNSCC were identified. We then used Cox regression analysis and least absolute shrinkage and selection operator (LASSO) analysis to explore IRDEGs related to the HNSCC prognosis and to construct and validate a risk scoring model and used ESTIMATE to evaluate tumor immune infiltration in HNSCC patients. Finally, we validated IGSF5 expression and function in HNSCC cells. A total of 1,195 IRDEGs were found from the GSE65858 dataset. Thirty-one of the 1,195 IRDEGs were associated with the prognosis of HNSCC. Nine key IRDEGs were further selected using the LASSO method, and a risk scoring model was established for predicting the survival of HNSCC patients. According to the risk scoring model, the prognosis of patients in the high-risk group was worse than that of the low-risk group; the high-risk group had significantly higher immune scores than the low-risk group; and between the high- and low-risk samples, there were significant differences in the proportion of 10 types of cells, including naive cells, plasma cells, and resting CD4+ memory T cells. IGSF5 has low expression in HNSCC, and overexpression of IGSF5 significantly impaired HNSCC cell proliferation. This prognostic risk assessment model can help systematically evaluate the survival prognosis of HNSCC patients and provides a new research direction for the improvement of the survival prognosis of HNSCC patients in clinical practice.

Chen Y ，Nie J ，Li X ，Fan T ，Deng X ，Liang D ，Song G ... -  《-》