Head And Neck Squamous Cell Carcinoma Research Articles

Impact of immune-related adverse events on survival among patients with head-and-neck squamous cell carcinoma.

Aim: Immune-checkpoint inhibitors (ICIs) have revolutionized treatment of metastatic head and neck squamous cell carcinomas (HNSCCs). Our goal was to assess for an association between immune-related adverse events (irAEs) and clinical outcomes for patients on ICIs.Methods: We analyzed a cohort of 110 HNSCC patients who received ICI therapy at the University of Virginia.Results: On review, 48% of our patients experienced an irAE with the most common events being hypothyroidism (30%), dermatitis (14%) and hepatitis (11%). Women were more likely to experience irAEs. Treatment interruption/discontinuation occurred in 43% patients with irAEs. Development of irAEs was associated with superior objective response rate (68 vs. 39%, p=0.009), with a greater rate of CR (17 vs. 5%) and PR (32vs. 16%). Twelve patients underwent ICI re-treatment following irAE, with 17% attaining a complete disease response, 25% attaining a partial response, 33% achieving stable disease and 25% experiencing disease progression with ICI resumption.Conclusion: Development of irAE was associated with superior objective response rate, with a greater rate of CR and PR. ICI re-treatment following irAE was feasible in a significant proportion of patients and can be attempted in carefully selected patients, given the dearth of second-line therapies for these patients.

Impact of protein kinase CK2 downregulation and inhibition on oncomir clusters 17 ~ 92 and 106b ~ 25 in prostate, breast, and head and neck cancers

BackgroundProtein kinase CK2 is a ubiquitous and highly conserved protein Ser/Thr kinase with diverse cell functions. CK2 is upregulated in various cancers and affects numerous aspects of their underlying pathobiology. The important role of microRNAs (miRNAs) referred to as oncomirs is also recognized in various cancers. Elevation of both CK2 and altered miRNA expression in cancers raised the question whether there was a connection between CK2 function and oncomirs in cancer.MethodsPCR array analysis was used to examine the effects of CK2 siRNA-mediated downregulation on miRNA levels in C4-2 prostate cancer cells. We employed prostate cancer, breast cancer, and head and neck squamous cell carcinoma (HNSCC) cells as well as a prostate cancer xenograft orthotopic tumor model to examine the effects of CK2 siRNA-mediated downregulation or chemical inhibition on oncomir cluster miR-17 ~ 92 and miR-106b ~ 25 constituent miRNAs by quantitative reverse-transcriptase stem-loop PCR. Pri-miRNAs were measured in cancer cell lines by quantitative reverse-transcriptase PCR. Protein levels were assessed by western blot. PC3-LN4 prostate cancer orthotopic xenograft tumors and blood were collected from nude mice following repeated treatments with tenfibgen ligand nanocapsules containing RNAi-CK2 or RNAi-Control cargoes.ResultsPCR array analysis demonstrated effect on a subset of miRNAs following CK2 downregulation; we focused our investigation on CK2 regulation of miR-17 ~ 92 and 106b ~ 25 oncomir clusters. Chemical inhibition or molecular downregulation of CK2 greatly reduced expression of miR-17 ~ 92 and 106b ~ 25 in prostate, breast and head and neck cancer cells in vitro. CK2α and CK2α´ protein levels were significantly correlated with many of the miR-17 ~ 92 and some of the miR-106b ~ 25 constituent members in prostate cancer cells. Decreased pri-miRNA levels for the miR-17 ~ 92 gene cluster transcript were observed for 5 of 6 cancer cell lines tested following CK2 downregulation. Nanocapsule-mediated delivery of RNAi-CK2 reduced CK2 protein expression in orthotopic prostate xenograft tumors and decreased intra-tumoral and serum levels of the oncomirs.ConclusionsTargeting CK2 for the development of new cancer therapies is under active investigation in many laboratories and pharmaceutical companies. Our data suggest a new role for CK2 in cell signaling and survival in multiple cancer types through maintenance of miR-17 ~ 92 and 106b ~ 25 biogenesis.

From Bench to Bedside: A Team's Approach to Multidisciplinary Strategies to Combat Therapeutic Resistance in Head and Neck Squamous Cell Carcinoma.

Head and neck squamous cell carcinoma (HNSCC) is diagnosed in more than 71,000 patients each year in the United States, with nearly 16,000 associated deaths. One significant hurdle in the treatment of HNSCC is acquired and intrinsic resistance to existing therapeutic agents. Over the past several decades, the University of Wisconsin has formed a multidisciplinary team to move basic scientific discovery along the translational spectrum to impact the lives of HNSCC patients. In this review, we outline key discoveries made throughout the years at the University of Wisconsin to deepen our understanding of therapeutic resistance in HNSCC and how a strong, interdisciplinary team can make significant advances toward improving the lives of these patients by combatting resistance to established therapeutic modalities. We are profoundly grateful to the many scientific teams worldwide whose groundbreaking discoveries, alongside evolving clinical paradigms in head and neck oncology, have been instrumental in making our work possible.

Correlation of the treatment sensitivity of patient-derived organoids with treatment outcomes in patients with head and neck cancer (SOTO): protocol for a prospective observational study

IntroductionOrganoids have been successfully used in several areas of cancer research and large living biobanks of patient-derived organoids (PDOs) have been developed from various malignancies. The characteristics of the original...

Nuclear TOP1MT Confers Cisplatin Resistance via Pseudogene in HNSCC

Cisplatin resistance is one of the major causes of treatment failure in head and neck squamous cell carcinoma (HNSCC). There is an urgent need to uncover the underlying mechanism for developing effective treatment strategies. A quantitative proteomics assay was used to identify differential proteins in cisplatin-resistant cells. Mitochondrial topoisomerase I (TOP1MT) localization was determined using laser confocal microscopy and nucleocytoplasmic separation assay. Chromatin immunoprecipitation sequencing, dual-luciferase reporter assay, and RNA immunoprecipitation were used to identify the interaction between pseudogenes, miRNAs, and real genes. In vivo experiments verified the interaction between TOP1MT and pseudogenes on cisplatin resistance. TOP1MT was identified as a driving factor of cisplatin resistance in vitro, in vivo, and in HNSCC patients. Moreover, TOP1MT exceptionally translocated to the nucleus in cisplatin-resistant HNSCC cells in a signal peptide–dependent manner. Nuclear TOP1MT (nTOP1MT) transcriptionally regulated the mitochondrial functional pseudogene MTATP6P1, which bound to miR-137 and miR-491-5p as a competing endogenous RNA (ceRNA) and promoted the expression of MTATP6. An increase in MTATP6 enhanced mitochondrial oxidative phosphorylation (OXPHOS), which conferred cisplatin resistance in HNSCC. Our findings revealed that nTOP1MT transcriptionally activated MTAPT6P1 and increased MTATP6 expression via ceRNA, which facilitated OXPHOS and cisplatin resistance. These results provide novel insight for overcoming cisplatin resistance in HNSCC.

IN VITRO ANTICANCER ACTIVITY OF HISTATIN-1 COMBINATION WITH CISPLATIN IN HEAD AND NECK CANCER CELL LINES.

Chemotherapy of head and neck squamous cell carcinoma (HNSCC) is associated with significant side effects. Antimicrobial peptides (AMPs), which are naturally occurring defense molecules like defensin-1 and LL-37 found in human secretions, have demonstrated potential in prompting tumor cell apoptosis and enhancing the effect of chemotherapeutic agents. However, the anticancer potential of histatin has not yet been thoroughly examined. The aim of the study was to explore the anticancer activity of histatin, an AMP present in human saliva and used alone or in combination with cisplatin in HNSCC cell lines. The gene expression of histatin was evaluated in the HSC4 and SCC25 cell lines by qRT-PCR. Cell proliferation was investigated at different concentrations of histatin peptide (His-1), cisplatin, and their combination using an MTT assay. SCC25 cells expressed both HTN1 (histatin-1) and HTN3 (histatin-3), whereas the HSC4 cell line expressed only HTN1. The combination of exogenous His-1 and cisplatin demonstrated a synergistic anti-proliferative effect against the HNSCC cell lines in a dosedependent manner. The combination of low-dose cisplatin and histatin inhibits HNSCC cell proliferation. His-1 sensitizes tumor cells to the cytotoxic effects of cisplatin potentially allowing for a reduction in its effective concentration.

Single cell analysis revealed SFRP2 cancer associated fibroblasts drive tumorigenesis in head and neck squamous cell carcinoma

Understanding the mechanisms of invasion and metastasis in head and neck squamous cell carcinoma (HNSCC) is crucial for effective treatment, particularly in metastatic cases. In this study, we analyzed multicenter bulk sequencing and comprehensive single-cell data from 702,446 cells, leading to the identification of a novel subtype of cancer-associated fibroblasts (CAFs), termed Secreted Frizzled-Related Protein2 CAFs (SFRP2_CAFs). These cells, originating from smooth muscle cells, display unique characteristics resembling both myofibroblastic CAFs and inflammatory CAFs, and are linked to poorer survival outcomes in HNSCC patients. Our findings reveal significant interactions between SFRP2_CAFs and SPP1 tumor-associated macrophages, which facilitate tumor invasion and metastasis. Moreover, our research identifies Nuclear factor I/X (NFIX) as a key transcription factor regulating SFRP2_CAFs behavior, confirmed through gene regulatory network analysis and simulation perturbation.

BANF1 is a novel prognostic biomarker linked to immune infiltration in head and neck squamous cell carcinoma.

Barrier-to-autointegration factor 1 (BANF1) is an abundant and ubiquitously expressed postnatal mammalian protein that is overexpressed in numerous human cancers and can promote cancer cell proliferation. However, the role of BANF1 in prognosis remains unclear in head and neck squamous cell carcinoma (HNSCC). BANF1 expression data were obtained from the GEO and TCGA databases. We used Cox regression and Kaplan-Meier curves to assess the prognostic potential of BANF1. The role of BANF1-related genes was investigated using Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment analyses. In addition, we explored the link between BANF1, drug sensitivity, and the tumor immune microenvironment. Finally, functional in vitro and in vivo assays were used to explore the effects of BANF1 on tumor growth and metastasis of HNSCC. BANF1 was markedly overexpressed in HNSCC and was correlated with clinicopathological characteristics. According to survival analysis, BANF1 can be inversely correlated with patient survival and can act as a prognostic risk indicator. IC50 values for chemotherapeutic treatments indicated that the group with high BANF1 expression was more responsive to most antitumor treatments. Furthermore, higher TIDE scores were observed in the low BANF1 expression group, indicating a decline in the efficacy of immune checkpoint inhibitor therapy. Functionally, the malignant biological behavior of HNSCC cell lines was inhibited when BANF1 expression was knocked down. BANF1 can promote tumor progression in patients with HNSCC. BANF1 shows great promise as a potential biomarker to assess the prognosis.

Phenotype remodelling of HNSCC cells in the muscle invasion environment

BackgroundTumour invading muscle in head and neck squamous cell carcinoma (HNSCC) is often associated with destructive growth and poor prognosis. However, the phenotypic functions and pathological mechanisms of muscle-invasive cancer cells in tumour progress remains unknown. In this study, we aimed to investigate the phenotypic functions of muscle-invasive cancer cells of HNSCC and their potential crosstalk with tumour microenvironment.MethodsWe obtained scRNA-seq data (SC) from GSE103322 (N = 18) and GSE181919 (N = 37), spatial RNA-seq data (ST) from GSE208253 and GSE181300 (N = 4), transcriptomics of human HNSCC samples from GSE42743 (N = 12) and GSE41613 (N = 97). Utilizing the TCGA-HNSC dataset, we conducted univariate and multivariate Cox analyses to investigate the prognostic impact of muscle-invasion in HNSCC, with validation in an additional cohort. Through Stutility and AUCell approaches, we identified and characterized muscle-invasive cancer cell clusters, including their functional phenotypes and gene-specific profiles. Integration of SC and ST data was achieved using Seurat analysis, multimodal intersection analysis, and spatial deconvolution. The results were further validated via in vitro and in vivo experiments.ResultsOur analyses of the TCGA-HNSC cohort revealed the presence of muscle-invasion was associated with a poor prognosis. By combining ST and SC, we identified muscle-invasive cancer cells exhibiting epithelial-to-mesenchymal transition (EMT) and myoepithelial-like transcriptional programs, which were correlated with a poor prognosis. Furthermore, we identified G0S2 as a novel marker of muscle-invasive malignant cells that potentially promotes EMT and the acquisition of myoepithelium-like phenotypes. These findings were validated through in vitro assays and chorioallantoic membranes experiments. Additionally, we demonstrated that G0S2-overexpressing cancer cells might attract human ECs via VEGF signalling. Subsequent in vitro and in vivo experiments revealed G0S2 plays key roles in promoting the proliferation and invasion of cancer cells.ConclusionsIn this study, we profiled the transcriptional programs of muscle-invasive HNSCC cell populations and characterized their EMT and myoepithelial-like phenotypes. Furthermore, our findings highlight the presence of muscle-invasion as a predictive marker for HNSCC patients. G0S2 as one of the markers of muscle-invasive cancer cells is involved in HNSCC intravasation, probably via VEGF signalling.

Plasmonics-enhanced spikey nanorattle-based biosensor for direct SERS detection of mRNA cancer biomarkers.

We present a plasmonics-enhanced spikey nanorattle-based biosensor for direct surface-enhanced Raman scattering (SERS) detection of mRNA cancer biomarkers. Early detection of cancers such as head and neck squamous cell carcinoma (HNSCC) is critical for improving patient outcomes in regions with limited access totraditional diagnostic methods. Our method targets Keratin 14 (KRT14), a promising diagnostic mRNA biomarker for HNSCC, using a sandwich hybridization approach with magnetic beads and SERS spikey nanorattles (SpNR). We synthesized SpNR with a core-gap-shell structure to enhance SERS signals, achieving a limit of detection of 90 femtomolar. A pilot study using clinical samples demonstrated the efficacy of our biosensor in distinguishing between tissue with positive or negative diagnosis for HNSCC, highlighting its potential for rapid and sensitive cancer diagnostics in low-resource settings. This plasmonic assay offers a promising avenue for portable and high-specificity detection of nucleic acid biomarkers, with implications for early cancer detection and improved patient care, especially in middle and low-resource settings.

Prognostic Significance of Programmed Cell Death-Ligand 1 Expression in Tobacco Associated Oral Squamous Cell Carcinoma: An Immunohistochemical Based Cross-Sectional Study.

Advancements in immuno-oncology have dramatically transformed cancer treatment. Immunotherapy, targeting immune check point proteins, notably Programmed cell death ligand 1 (PD-L1) and its receptor Programmed Cell Death-1 (PD-1) which modulate the activity of immune response in Head and Neck squamous cell carcinomas (HNSCC), is an area of much research. The immunohistochemical expression of PD-L1 in cancer cells has been proposed as a predictive biomarker for selecting candidates for immunotherapy. Thus, the present study was undertaken to study the expression of PD-L1 in the primary tumour cells and evaluate its correlation with various clinicopathological parameters and prognosis in tobacco associated oral squamous cell carcinomas (OSCC). Expression of PD-L1 was investigated in 75 surgically resected cases of OSCC by immunohistochemistry and its association with different clinicopathological features and prognosis was analysed. PD-L1 protein was detected in 68% (51 cases) of cases. Tumour stage (p = 0.04), lymph node (LN) metastasis (p < 0.01) and moderate to marked tumour infiltrating lymphocytes (TILs) (p < 0.05), significantly correlated with the PD-L1 expression in the primary tumour. PD-L1 expression did not show a significant association with overall survival (OS) rate, however, patients with positive PD-L1 expression showed a poorer survival rate. Patients exhibiting nodal positivity had the worst prognosis (p < 0.005). These data demonstrated a significant association of ≥ 5% PD-L1 expression in the primary tumour and the presence of LN metastasis, moderate to marked TILs and advancing tumour stage, thus, making it a plausible immunotherapeutic target molecule in OSCC patients.

A Review of Immunotherapy for Head and Neck Cancer

The introduction of immune checkpoint inhibitors (ICIs) to oncological care has transformed the management of various malignancies, including head and neck squamous cell carcinoma (HNSCC), offering improved outcomes. The first-line treatment of recurrent and malignant HNSCC for many years was combined platinum, 5-fluorouracil, and cetuximab. Recently, the ICI pembrolizumab was approved as a first-line treatment, with or without chemotherapy, based on tumor and immune cell percentage of programmed-death ligand 1 (PD-L1). Multiple head and neck (HN) cancer trials have subsequently explored immunotherapies in combination with surgery, chemotherapy, and/or radiation. Immunotherapy regimens may be personalized by tumor biomarker, including PD-L1 content, tumor mutational burden, and microsatellite instability. However, further clinical trials are needed to refine biomarker-driven protocols and standardize pathological methods to guide combined regimen timing, sequencing, and deescalation. Gaps remain for protocols using immunotherapy to reverse oral premalignant lesions, particularly high-risk leukoplakias. A phase II nonrandomized controlled trial, using the ICI nivolumab, showed a 2-y cancer-free survival of 73%, although larger trials are needed. Guidelines are also needed to standardize the role of dental evaluation and care before, during, and after immunotherapy, specifically in regard to oral immune-related adverse events and their impact on cancer recurrence. Standardized diagnostic and oral care coordination strategies to close these gaps are needed to ensure continued success of HN cancer immunotherapy.

Socioeconomic Deprivation Correlates With Incomplete Radiotherapy Treatment in Head and Neck Cancer

There is a high burden of socioeconomic deprivation across Merseyside and, along with this, poorer cancer outcomes. The incidence of head and neck squamous cell carcinoma (HNSCC) within this region is higher than the national average and there are often additional complexities to individual treatment pathways such as poor health literacy, lack of social support and transport options which can impact on adherence to prescribed treatments. AimsThis work aims to understand the impact of deprivation on patients diagnosed with HNSCC undergoing chemoradiotherapy (CRT) or radiotherapy (RT) treatment by identifying barriers to adherence. Materials and methodsPatients with HNSCC treated between June 2022 and June 2023 were included and data was collected through retrospective case note review. Approval was obtained from relevant NHS institution audit departments. Key examined variables were indices of multiple deprivation (IMD), unplanned admission rate, hospital transport use, social support network and provision of additional ad hoc appointments during treatment courses. All were correlated with missed radiotherapy appointments. ResultsOut of 359 evaluable patients there were high levels of unplanned appointments with health professionals during CRT/RT (71% of those receiving CRT and 55% of those having RT). 11% (n = 39) missed at least one radiotherapy appointment with the commonest reason being unplanned admission to hospital. Despite missed appointments, 25/39 patients completed treatment within prescribed window due to effective RT compensation strategies. On multivariate analysis, unplanned admission, hospital-provided transport and crime deprivation quintiles (p=<0.001, p = 0.007 and p = 0.027, respectively) were found to significantly increase the chance of missed radiotherapy treatment appointments. ConclusionHigh levels of unplanned encounters with health care professionals are encouraging adherence to non-surgical HNSCC treatments. Formalising these ad hoc appointments will provide an equitable, robust service. Undertaking hospital transport increases the potential for missed treatment appointments. Gaining insight into patient experiences and investing in improved transport services are essential for maximising adherence.

Human papillomavirus-encoded circular RNA circE7 promotes immune evasion in head and neck squamous cell carcinoma

Immune evasion represents a crucial milestone in the progression of cancer and serves as the theoretical foundation for tumor immunotherapy. In this study, we reveal a negative association between Human Papillomavirus (HPV)-encoded circular RNA, circE7, and the infiltration of CD8+ T cells in head and neck squamous cell carcinoma (HNSCC). Both in vitro and in vivo experiments demonstrate that circE7 suppresses the function and activity of T cells by downregulating the transcription of LGALS9, which encodes the galectin-9 protein. The molecular mechanism involves circE7 binding to acetyl-CoA carboxylase 1 (ACC1), promoting its dephosphorylation and thereby activating ACC1. Activated ACC1 reduces H3K27 acetylation at the LGALS9 gene promoter, leading to decreased galectin-9 expression. Notably, galectin-9 interacts with immune checkpoint molecules TIM-3 and PD-1, inhibiting the secretion of cytotoxic cytokines by T cells and promoting T cell apoptosis. Here, we demonstrate a mechanism by which HPV promotes immune evasion in HNSCC through a circE7-driven epigenetic modification and propose a potential immunotherapy strategy for HNSCC that involves the combined use of anti-PD-1 and anti-TIM-3 inhibitors.

Roles of ZEB1 and ZEB2 in E-cadherin expression and cell aggressiveness in head and neck cancer.

Zinc finger E-box binding homeobox 1 (ZEB1) has been identified as a key factor in cancer cell differentiation and metastasis, and has been well studied in the field of cancer cell biology. ZEB2 has a highly similar conformation to ZEB1, but its role in head and neck squamous cell carcinoma (HNSCC) cells is not fully understood. Here, we separately overexpressed ZEB1 and ZEB2 in C57BL/6 mouse oral cancer (MOC) cells and investigated their cellular characteristics, including E-cadherin levels, motile properties, chemoresistance, and metastatic ability in immunocompetent mice. Both ZEB1 and ZEB2 overexpression reduced epithelial traits and converted cells to an aggressive phenotype. Surprisingly, ZEB1 overexpression increased the endogenous level of ZEB2 in MOC cells, and vice versa. The molecular mechanisms underlying these findings remain unclear. However, the in vitro anchorage-independent growth of MOC cells overexpressing ZEB2 was considerably greater than that of MOC cells overexpressing ZEB1. These findings suggest that ZEB2, like ZEB1, has the ability to induce the differentiation of cancer cells into those with highly aggressive traits.

Mucosa-like differentiation of head and neck cancer cells is inducible and drives the epigenetic loss of cell malignancy

Head and neck squamous cell carcinoma (HNSCC) is a highly malignant disease with high death rates that have remained substantially unaltered for decades. Therefore, new treatment approaches are urgently needed. Human papillomavirus-negative tumors harbor areas of terminally differentiated tissue that are characterized by cornification. Dissecting this intrinsic ability of HNSCC cells to irreversibly differentiate into non-malignant cells may have tumor-targeting potential. We modeled the cornification of HNSCC cells in a primary spheroid model and analyzed the mechanisms underlying differentiation by ATAC-seq and RNA-seq. Results were verified by immunofluorescence using human HNSCC tissue of distinct anatomical locations. HNSCC cell differentiation was accompanied by cell adhesion, proliferation stop, diminished tumor-initiating potential in immunodeficient mice, and activation of a wound-healing-associated signaling program. Small promoter accessibility increased despite overall chromatin closure. Differentiating cells upregulated KRT17 and cornification markers. Although KRT17 represents a basal stem cell marker in normal mucosa, we confirm KRT17 to represent an early differentiation marker in HNSCC tissue. Cornification was frequently found surrounding necrotic areas in human tumors, indicating an involvement of pro-inflammatory stimuli. Indeed, inflammatory mediators activated the differentiation program in primary HNSCC cells. In HNSCC tissue, distinct cell differentiation states were found to create a common tissue architecture in normal mucosa and HNSCCs. Our data demonstrate a loss of cell malignancy upon faithful HNSCC cell differentiation, indicating that targeted differentiation approaches may be therapeutically valuable. Moreover, we describe KRT17 to be a candidate biomarker for HNSCC cell differentiation and early tumor detection.

Novel Predictive Biomarkers in the Head and Neck Squamous Cell Carcinoma (HNSCC).

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide, characterized by high aggressiveness and frequent metastasis to regional lymph nodes. Despite advances in therapy, including checkpoint inhibitor immunotherapy, surgery, radiotherapy, and chemotherapy, survival rates for patients with advanced HNSCC remain unsatisfactory. This article presents the latest research on predictive biomarkers such as PD-L1, PD-1, CTLA-4, p53, and HPV, which may enhance treatment efficacy and improve clinical outcomes for patients. The clinical value of these biomarkers, their limitations, and their potential application in HNSCC therapy are emphasized. Special attention is given to immunotherapy, which shows promising results in treating this type of cancer through the modulation of the immune response. The review's findings highlight the need for further research on new biomarkers to develop more personalized and effective therapeutic strategies for HNSCC patients.

The branched N-glycan of PD-L1 predicts immunotherapy responses in patients with recurrent/metastatic HNSCC

Immunotherapy has revolutionized cancer treatment, but the lack of a reliable predictive biomarker for treatment response remains a challenge. Alpha-1,6-Mannosylglycoprotein 6-β-N-Acetylglucosaminyltransferase 5 (MGAT5) is a key regulator of complex N-glycan synthesis, and its dysregulation is associated with cancer progression. The lectin Phaseolus vulgaris leukoagglutinin (PHA-L) specifically binds to mature MGAT5 products. Previous studies have indicated elevated PHA-L staining in head and neck squamous cell carcinoma (HNSCC), which implies increased activity of MGAT5. However, the specific role of MGAT5 in HNSCC remains unclear. In this study, we found significantly higher PHA-L staining and MGAT5 expression in HNSCC tumors compared to adjacent non-tumor tissues. Using a mass spectrometry (MS)-based glycoproteomic approach, we identified 163 potential protein substrates of MGAT5. Functional analysis revealed that protein substrates of MGAT5 regulated pathways related to T cell proliferation and activation. We further discovered that PD-L1 was among the protein substrates of MGAT5, and the expression of MGAT5 protected tumor cells from cytotoxic T lymphocyte (CTL) killing. Treatment of nivolumab alleviated the protective effects of MGAT5 on CTL activity. Consistently, patients with MGAT5-positive tumors showed improved responses to immunotherapy compared to those with MGAT5-negative tumors. Using purified PD-L1 from HNSCC cells and a glycoproteomic approach, we further deciphered that the N35 and N200 sites carry the majority of complex N-glycans on PD-L1. Our findings highlight the critical role of MGAT5-mediated branched N-glycans on PD-L1 in modulating the interaction with the immune checkpoint receptor PD-1. Consequently, we propose that MGAT5 could serve as a biomarker to predict patients’ responses to anti-PD-1 therapy. Furthermore, targeting the branched N-glycans at N35 and N200 of PD-L1 may lead to the development of novel diagnostic and therapeutic approaches.

The m6A and immune regulatory gene signature predicts the prognosis and correlates with immune infiltration of head and neck squamous cell carcinoma

Recent investigations have underscored the epigenetic modulation of the immune response; however, the interplay between RNA N6-methyladenosine (m6A) modification and immunomodulation in head and neck squamous cell carcinoma (HNSC) remains relatively unexplored. To bridge this knowledge gap, we undertook an extensive examination of the potential contributions of m6A modification and immunomodulation in HNSC. We amalgamated and deduplicated 27 m6A -related genes (m6AGs) and 1342 immune regulation-related genes (IMRGs), resulting in a comprehensive dataset encompassing 1358 genes. This dataset was scrutinized for m6A modification and immunomodulatory patterns within HNSC specimens. Employing Cox regression analysis and the Least Absolute Shrinkage and Selection Operator (LASSO) technique, we developed a prognostic risk model for m6A regulator-mediated methylation modification and immunomodulation-related differentially expressed genes (m6A&IMRDEGs). Our differential expression analysis delineated 29 m6A&IMRDEGs, and Weighted Gene Co-expression Network Analysis (WGCNA) elucidated two module genes (IL11 and MMP13) subjected to correlation analysis. The prognostic prediction models revealed that the clinical predictive efficacy peaked for 1-year forecasts, followed sequentially by 3-year and 5-year predictions. The risk scores derived from the model adeptly categorized HNSC patients into high- and low-risk cohorts, with the high-risk group exhibiting a more unfavorable prognosis. Protein-Protein Interaction (PPI) analysis identified 7 hub genes implicated in m6A and immune regulation, namely BPIFB1, BPIFB2, GP2, MUC5B, MUC7, PIP, and SCGB3A1. Furthermore, we noted marked disparities in the expression profiles of 18 immune cell types between the high- and low-risk groups. Our results substantiate that the clustering subpopulations and risk models associated with m6A and immune regulatory genes portend a poor prognosis in HNSC. The risk score emerges as a potent prognostic biomarker and predictive metric for HNSC patients. A thorough assessment of m6A and immune regulatory genes in HNSC will augment our comprehension of the tumor immune microenvironment and facilitate the advancement of HNSC therapeutics.

Regulatory Effects of SLC7A2-CPB2 on Lymphangiogenesis: A New Approach to Suppress Lymphatic Metastasis in HNSCC.

Lymph node metastasis (LNM) is a critical factor affecting the outcomes of head and neck squamous cell carcinoma (HNSCC) and the main reason for treatment failure. This study was designed to examine the effects of the key genes involved in the LNM of HNSCC. Tissue samples (HNSCC) were examined by transcriptome sequencing, and the core genes associated with LNM were detected via bioinformatics analysis. The functions of these core genes were then validated using the TCGA biological database and their effects on the propagation, invasion, and metastasis of HNSCC cells were evaluated through cell culture experiments. Moreover, the effect of core gene expression on the LNM capability of HNSCC was confirmed via a footpad xenograft mice model. In the findings, a key gene involved in the LNM of HNSCC was identified as SLC7A2. It was correlated with adverse clinical prognosis and expressed with low expression in HNSCC tissues. As shown in cell culture experiments, FaDu and SCC15 cell growth, invasion, and migration were inhibited when SLC7A2 was overexpressed. Further, cell apoptosis was stimulated, and lymphangiogenesis was suppressed through the downregulation of CPB2 expression. Animal studies demonstrated that the growth and LNM of HNSCC cells were inhibited by SLC7A2 overexpression. It is concluded that SLC7A2 is involved in HNSCC lymphatic metastasis by controlling CPB2 function. The results are anticipated to offer new directions for the effective treatment of HNSCC.