Tumor-associated genetic amplifications impact extracellular vesicle miRNA cargo and their recruitment of nerves in head and neck cancer.

Cancer neuroscience is an emerging field of cancer biology focused on defining the interactions and relationships between the nervous system, developing malignancies, and their environments. Our previous work demonstrates that small extracellular vesicles (sEVs) released by head and neck squamous cell carcinomas (HNSCCs) recruit loco-regional nerves to the tumor. sEVs contain a diverse collection of biological cargo, including microRNAs (miRNAs). Here, we asked whether two genes commonly amplified in HNSCC, CCND1, and PIK3CA, impact the sEV miRNA cargo and, subsequently, sEV-mediated tumor innervation. To test this, we individually overexpressed these genes in a syngeneic murine HNSCC cell line, purified their sEVs, and tested their neurite outgrowth activity on dorsal root ganglia (DRG) neurons in vitro. sEVs purified from Ccnd1-overexpressing cells significantly increased neurite outgrowth of DRG compared to sEVs from parental or Pik3ca over-expressing cells. When implanted into C57BL/6 mice, Ccnd1 over-expressing tumor cells promoted significantly more tumor innervation in vivo. qPCR analysis of sEVs shows that increased expression of Ccnd1 altered the packaging of miRNAs (miR-15-5p, miR-17-5p, and miR-21-5p), many of which target transcripts important in regulating axonogenesis. These data indicate that genetic amplifications harbored by malignancies impose changes in sEV miRNA cargo, which can influence tumorc innervation.

CTHRC1 is a prognostic biomarker correlated with immune infiltration in head and neck squamous cell carcinoma.

BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) is the sixth most common malignancy worldwide, characterized by high morbidity, high mortality, and poor prognosis. Collagen triple helix repeat containing 1 (CTHRC1) has been shown to be highly expressed in various cancers. However, its biological functions, potential role as a biomarker, and its relationship with immune infiltrates in HNSCC remain unclear. Our principal objective was to analyze CTHRC1 expression, its prognostic implications, biological functions, and its effects on the immune system in HNSCC patients using bioinformatics analysis. METHODS: The expression matrix was obtained from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). CTHRC1 expression in HNSCC was analyzed between tumor and adjacent normal tissues, different stages were compared, and its impact on clinical prognosis was assessed using Kaplan-Meier analysis. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Gene Set Variation Analysis (GSVA) were employed for enrichment analysis. The Search Tool for the Retrieval of Interacting Genes database (STRING) was used to analyze protein-protein interactions. Pearson correlation tests were used to investigate the association between CTHRC1 expression and immune checkpoints. The correlation between CTHRC1 and immune infiltration was investigated using CIBERSORT, TIMER, and ESTIMATE. RESULTS: Compared to adjacent normal tissues, CTHRC1 was found to be highly overexpressed in tumors. Increased expression of CTHRC1 was more evident in the advanced stage of HNSCC and predicted a poor prognosis. Most genes related to CTHRC1 in HNSCC were enriched in physiological functions of Extracellular matrix(ECM) and tumor. Furthermore, several immune checkpoints, such as TNFSF4 and CD276 have been shown to be associated with CTHRC1 expression. Notably, the level of CTHRC1 expression correlated significantly with immune infiltration levels, particularly activated macrophages in HNSCC. CONCLUSIONS: High expression of CTHRC1 predicts poor prognosis and is associated with immune infiltration in HNSCC, confirming its utility as a tumor marker for HNSCC. TRIAL REGISTRATION: Not applicable. All data are from public databases and do not contain any clinical trials.

A druggable cascade links methionine metabolism to epigenomic reprogramming in squamous cell carcinoma.

Upper aerodigestive squamous cell carcinoma (UASCC) is a common and aggressive malignancy with few effective therapeutic options. Here, we investigate amino acid metabolism in this cancer, surprisingly noting that UASCC exhibits the highest methionine level across all human cancers, driven by its transporter LAT1. We show that LAT1 is also expressed at the highest level in UASCC, transcriptionally activated by UASCC-specific promoter and enhancers, which are directly coregulated by SCC master regulators TP63/KLF5/SREBF1. Unexpectedly, unbiased bioinformatic screen identifies EZH2 as the most significant target downstream of the LAT1-methionine pathway, directly linking methionine metabolism to epigenomic reprogramming. Importantly, this cascade is indispensable for the survival and proliferation of UASCC patient-derived tumor organoids. In addition, LAT1 expression is closely associated with cellular sensitivity to inhibition of the LAT1-methionine-EZH2 axis. Notably, this unique LAT1-methionine-EZH2 cascade can be targeted effectively by either pharmacological approaches or dietary intervention in vivo. In summary, this work maps a unique mechanistic cross talk between epigenomic reprogramming with methionine metabolism, establishes its biological significance in the biology of UASCC, and identifies a unique tumor-specific vulnerability which can be exploited both pharmacologically and dietarily.

Understanding Hypoxia-Driven Tumorigenesis: The Interplay of HIF1A, DNA Methylation, and Prolyl Hydroxylases in Head and Neck Squamous Cell Carcinoma.

Hypoxia-inducible factor 1-alpha (HIF1A) is a key transcription factor aiding tumor cells' adaptation to hypoxia, regulated by the prolyl hydroxylase family (EGLN1-3) by directing toward degradation pathways. DNA methylation potentially influences EGLN and HIF1A levels, impacting cellular responses to hypoxia. We examined 96 HNSCC patients and three cell lines, analyzing gene expression of EGLN1-3, HIF1A, CA9, VEGF, and GLUT1 at the mRNA level and EGLN1 protein levels. Methylation levels of EGLNs and HIF1A were assessed through high-resolution melting analysis. Bioinformatics tools were employed to characterize associations between EGLN1-3 and HIF1A expression and methylation. We found significantly higher mRNA levels of EGLN3, HIF1A, GLUT1, VEGF, and CA9 (p = 0.021; p < 0.0001; p < 0.0001; p = 0.004, and p < 0.0001, respectively) genes in tumor tissues compared to normal ones and downregulation of the EGLN1 mRNA level in tumor tissues (p = 0.0013). In HNSCC patients with hypermethylation of HIF1A in normal tissue, we noted a reduction in HIF1A mRNA levels compared to tumor tissue (p = 0.04). In conclusion, the differential expression of EGLN and HIF1A genes in HNSCC tumors compared to normal tissues influences patients' overall survival, highlighting their role in tumor development. Moreover, DNA methylation could be responsible for HIF1A suppression in the normal tissues of HNSCC patients.

Context-Dependent Regulation of Peripheral Nerve Abundance by the PI3K Pathway in the Tumor Microenvironment of Head and Neck Squamous Cell Carcinoma.

Recent studies have highlighted neurons and their associated Schwann cells (SCs) as key regulators of cancer development. However, the mode of their interaction with tumor cells or other components of the tumor microenvironment (TME) remains elusive. We established an SC-related 43-gene set as a surrogate for peripheral nerves in the TME. Head and neck squamous cell carcinoma (HNSCC) from The Cancer Genome Atlas (TCGA) were classified into low, intermediate and high SC score groups based on the expression of this gene set. Perineural invasion (PNI) and TGF-ß signaling were hallmarks of SChigh tumors, whereas SClow tumors were enriched for HPV16-positive OPSCC and higher PI3K-MTOR activity. The latter activity was partially explained by a higher frequency of PTEN mutation and PIK3CA copy number gain. The inverse association between PI3K-MTOR activity and peripheral nerve abundance was context-dependent and influenced by the TP53 mutation status. An in silico drug screening approach highlighted the potential vulnerabilities of HNSCC with variable SC scores and predicted a higher sensitivity of SClow tumors to DNA topoisomerase inhibitors. In conclusion, we have established a tool for assessing peripheral nerve abundance in the TME and provided new clinical and biological insights into their regulation. This knowledge may pave the way for new therapeutic strategies and impart proof of concept in appropriate preclinical models.

Tigilanol Tiglate-Induced Changes in Secretome Profiles Alter C-Met Phosphorylation and Cell Surface Protein Expression in H357 Head and Neck Cancer Cells.

Tigilanol tiglate (TT, also known as EBC-46) is a novel, plant-derived diterpene ester possessing anticancer and wound-healing properties. Here, we show that TT-evoked PKC-dependent S985 phosphorylation of the tyrosine kinase MET leads to subsequent degradation of tyrosine phosphorylated p-Y1003 and p-Y1234/5 MET species. PKC inhibition with BIM-1 blocked S985 phosphorylation of MET and led to MET cell surface accumulation. Treatment with metalloproteinase inhibitors prevented MET-ECD release into cell culture media, which was also blocked by PKC inhibitors. Furthermore, unbiased secretome analysis, performed using TMT-technology, identified additional targets of TT-dependent release of cell surface proteins from H357 head and neck cancer cells. We confirm that the MET co-signalling receptor syndecan-1 was cleaved from the cell surface in response to TT treatment. This was accompanied by rapid cleavage of the cellular junction adhesion protein Nectin-1 and the nerve growth factor receptor NGFRp75/TNFR16. These findings, that TT is a novel negative regulator of protumorigenic c-MET and NGFRp75/TNFR16 signalling, as well as regulating Nectin-1-mediated cell adhesion, further contribute to our understanding of the mode of action and efficacy of TT in the treatment of solid tumours.

Multi omics analysis of mitophagy subtypes and integration of machine learning for predicting immunotherapy responses in head and neck squamous cell carcinoma.

Mitophagy serves as a critical mechanism for tumor cell death, significantly impacting the progression of tumors and their treatment approaches. There are significant challenges in treating patients with head and neck squamous cell carcinoma, underscoring the importance of identifying new targets for therapy. The function of mitophagy in head and neck squamous carcinoma remains uncertain, thus investigating its impact on patient outcomes and immunotherapeutic responses is especially crucial. We initially analyzed the differential expression, prognostic value, intergene correlations, copy number variations, and mutation frequencies of mitophagy-related genes at the pan-cancer level. Through unsupervised clustering, we divided head and neck squamous carcinoma into three subtypes with distinct prognoses, identified the signaling pathway features of each subtype using ssGSEA, and characterized subtype B as having features of an immune desert using various immune infiltration calculation methods. Using multi-omics data, we identified the genomic variation characteristics, mutated gene pathway features, and drug sensitivity features of the mitophagy subtypes. Utilizing a combination of 10 machine learning algorithms, we have developed a prognostic scoring model called Mitophagy Subgroup Risk Score (MSRS), which is used to predict patient survival and the response to immune checkpoint blockade therapy. Simultaneously, we applied MSRS to single-cell analysis to explore intercellular communication. Through laboratory experiments, we validated the biological function of SLC26A9, one of the genes in the risk model. In summary, we have explored the significant role of mitophagy in head and neck tumors through multi-omics data, providing new directions for clinical treatment.

Integrative single-cell and bulk transcriptomes analyses reveals heterogeneity of serine-glycine-one-carbon metabolism with distinct prognoses and therapeutic vulnerabilities in HNSCC.

Metabolic heterogeneity plays a central role in sustaining uncontrolled cancer cell proliferation and shaping the tumor microenvironment (TME), which significantly compromises the clinical outcomes and responses to therapy in head and neck squamous cell carcinoma (HNSCC) patients. This highlights the urgent need to delineate the intrinsic heterogeneity and biological roles of metabolic vulnerabilities to advance precision oncology. The metabolic heterogeneity of malignant cells was identified using single-cell RNA sequencing (scRNA-seq) profiles and validated through bulk transcriptomes. Serine-glycine-one-carbon (SGOC) metabolism was screened out to be responsible for the aggressive malignant properties and poor prognosis in HNSCC patients. A 4-SGOC gene prognostic signature, constructed by LASSO-COX regression analysis, demonstrated good predictive performance for overall survival and therapeutic responses. Patients in the low-risk group exhibited greater infiltration of exhausted CD8+ T cells, and demonstrated better clinical outcomes after receiving immunotherapy and chemotherapy. Conversely, high-risk patients exhibited characteristics of cold tumors, with enhanced IMPDH1-mediated purine biosynthesis, resulting in poor responses to current therapies. IMPDH1 emerged as a potential therapeutic metabolic target. Treatment with IMPDH inhibitors effectively suppressed HNSCC cell proliferation and metastasis and induced apoptosis in vitro and in vivo by triggering GTP-exhaustion nucleolar stress. Our findings underscore the metabolic vulnerabilities of HNSCC in facilitating accurate patient stratification and individualized precise metabolic-targeted treatment.

FAP Serves as a Prognostic Biomarker in Head and Neck Squamous Cell Carcinoma.

Head and neck squamous cell carcinoma (HNSCC) poses significant challenges with poor survival rates and limited therapeutic strategies. Our study, using The Cancer Genome Atlas (TCGA) data, assesses cancer-associated fibroblast (CAF) gene signatures' clinical relevance. In our analysis across TCGA tumor types, differential gene expression analysis revealed that fibroblast activation protein (FAP) is upregulated in tumor tissues and associated with poorer survival rates in HNSCC. Furthermore, mechanistic studies employing gene-silencing techniques substantiated that FAP knockout led to a significant decrease in cellular proliferation, invasion, and migration in HNSCC cell lines. Through Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses, we established that high FAP expression correlates with vital biological processes such as extracellular matrix organization, angiogenesis, and cellular motility. Importantly, FAP was found to regulate these processes by promoting the expression of key proteins involved in epithelial-mesenchymal transition-related pathways. Additionally, our analysis revealed a significant correlation between FAP expression and the expression profiles of immune checkpoint molecules, underscoring its potential role in immune modulation. Collectively, our findings illuminate FAP's pivotal role in HNSCC pathogenesis and its potential as a prognostic biomarker and therapeutic target. This research lays the groundwork for understanding the multifaceted roles and regulatory mechanisms of CAFs in HNSCC, thereby offering valuable perspectives for the development of targeted therapeutic strategies aimed at improving patient outcomes.

Proton therapy re-irradiation outcomes and genomic landscape of patients with recurrent head and neck cancer.

INTRODUCTION: Re-irradiation (re-RT) for recurrent head and neck cancer (rHNC) is challenging. We describe clinical outcomes and toxicity of proton therapy (PT) for recurrent HNC, and report genomic alterations associated with patterns of failure. MATERIALS & METHODS: We performed a retrospective analysis of rHNC patients treated with PT. Outcomes were estimated using the Kaplan-Meier method. Univariate (UVA) and multivariate analyses (MVA) were performed to assess multiple patient factors. Next-generation sequencing and genomic analyses were performed on available samples. RESULTS: Eighty-nine patients treated with PBS-PT for rHNC with a median follow-up of 12 mo (0-71 mo) were included. The 1- and 2-y local control (LC) rates were 80.8 % (95 % CI: 70.8-90.8) and 66.2 % (95 % CI: 50.7-81.7), and 1- and 2-y distant metastasis-free survival (DMFS) were 41.0 % (95 % CI: 30.0-52.0) and 26.3 % (95 % CI: 15.7-36.9). The median overall survival (OS) was 13 mo (95 % CI: 9.3-16.7). On UVA and MVA, smaller gross tumor volume (GTV) was associated with improved OS (HR 1.002, P = 0.004), DMFS (HR 1.002, P = 0.004), and PFS (HR 1.002, P = 0.014). There were 35 late Gr3 + toxicity events (30.3 %). Patients with higher candidate gene-specific mutation burden (genes with [OR] > 2, P < 0.05) had inferior PFS. TP53, NOTCH4, and ARID1B mutations were associated with inferior DMFS (OR > 2, P < 0.05). CONCLUSIONS: PBS-PT is effective at achieving LC for rHNC with favorable toxicity. Distant metastases are common, and associated with TP53, NOTCH4, and ARID1B mutations. Inclusion of genomic alterations in the clinical decision process may be warranted.

Autophagy is the main driver of radioresistance of HNSCC cells in mild hypoxia.

Hypoxia poses a significant challenge to the effectiveness of radiotherapy in head and neck squamous cell carcinoma (HNSCC) patients, and it is imperative to discover novel approaches to overcome this. In this study, we investigated the underlying mechanisms contributing to x-ray radioresistance in HPV-negative HNSCC cells under mild hypoxic conditions (1% oxygen) and explored the potential for autophagy modulation as a promising therapeutic strategy. Our findings show that HNSCC cells exposed to mild hypoxic conditions exhibit increased radioresistance, which is largely mediated by the hypoxia-inducible factor (HIF) pathway. We demonstrate that siRNA knockdown of HIF-1α and HIF-1ß leads to increased radiosensitivity in HNSCC cells under hypoxia. Hypoxia-induced radioresistance was not attributed to differences in DNA double strand break repair kinetics, as these remain largely unchanged under normoxic and hypoxic conditions. Rather, we identify autophagy as a critical protective mechanism in HNSCC cells following irradiation under mild hypoxia conditions. Targeting key autophagy genes, such as BECLIN1 and BNIP3/3L, using siRNA sensitizes these cells to irradiation. Whilst autophagy's role in hypoxic radioresistance remains controversial, this study highlights the importance of autophagy modulation as a potential therapeutic approach to enhance the effectiveness of radiotherapy in HNSCC.

Construction of a nomogram for predicting HNSCC distant metastasis and identification of EIF5A as a hub gene.

Patients with distant metastasis of head and neck squamous cell carcinoma (HNSCC) often have a poor prognosis. However, early diagnosis of distant metastasis is challenging in clinical practice, and distant metastasis is often only detected in the late stages of tumor metastasis through imaging techniques. In this study, we utilized data from HNSCC patients collected from the TCGA database. Patients were divided into distant metastasis and nonmetastasis groups based on the tumor-node-metastasis (TNM) stage. We analyzed the differentially expressed genes between the two groups (DM/non-M DEGs) and their associated lncRNAs and generated a predictive model based on 23 lncRNAs that were significantly associated with the occurrence of distant metastasis in HNSCC patients. On this basis, we built a nomogram to predict the distant metastasis of HNSCC patients. Moreover, through WGCNA and Cytoscape software analysis of DM/non-M DEGs, we identified the gene most closely related to HNSCC distant metastasis: EIF5A. Our findings were validated using GEO data; EIF5A expression was significantly increased in the tumor tissues of HNSCC patients with distant metastasis. We then predicted miRNAs that can directly bind to EIF5A via the TargetScan and miRWalk websites, intersected them with differentially expressed miRNAs in the two groups from the TCGA cohort, and identified the only overlapping miRNA, miR-424; we predicted the direct binding site of EIF5A and miR-424 via the miRWalk website. Immunohistochemistry further revealed high expression of EIF5A in the primary tumor tissue of HNSCC patients with distant metastasis. These results provide a new perspective for the early diagnosis of distant metastasis in HNSCC patients and the study of the mechanisms underlying HNSCC distant metastasis.

Single-Cell Molecular Profiling of Head and Neck Squamous Cell Carcinoma Reveals Five Dysregulated Signaling Pathways Associated With Circulating Tumor Cells.

OBJECTIVES: To determine the dysregulated signaling pathways of head and neck squamous cell carcinoma associated with circulating tumor cells (CTCs) via single-cell molecular characterization. INTRODUCTION: Head and neck squamous cell carcinoma (HNSCC) has a significant global burden and is a disease with poor survival. Despite trials exploring new treatment modalities to improve disease control rates, the 5 year survival rate remains low at only 60%. Most cancer malignancies are reported to progress to a fatal phase due to the metastatic activity derived from treatment-resistant cancer cells, regarded as one of the most significant obstacles to develope effective cancer treatment options. However, the molecular profiles of cancer cells have not been thoroughly studied. METHODS: Here, we examined in-situ HNSCC tumors and pairwisely followed up with the downstream circulating tumor cells (CTCs)-based on the surrogate biomarkers to detect metastasis that is established in other cancers - not yet being fully adopted in HNSCC treatment algorithms. RESULTS: Specifically, we revealed metastatic HNSCC patients have complex CTCs that could be defined through gene expression and mutational gene profiling derived from completed single-cell RNASeq (scRNASeq) that served to confirm molecular pathways inherent in these CTCs. To enhance the reliability of our findings, we cross-validated those molecular profiles with results from previously published studies. CONCLUSION: Thus, we identified 5 dysregulated signaling pathways in CTCs to derive HNSCC biomarker panels for screening HNSCC in situ tumors.

ObjectivesInvestigating the dysregulated signaling pathways of head and neck squamous cell carcinoma (HNSCC) linked with circulating tumor cells (CTCs) using single-cell molecular characterization.IntroductionHNSCC poses a significant global health burden with poor survival rates despite advancements in treatment. Metastatic activity from treatment-resistant cancer cells remains a major challenge in developing effective treatments. However, the molecular profiles of cancer cells, particularly CTCs, are not well-understood.MethodsWe analyzed in-situ HNSCC tumors and corresponding CTCs using surrogate biomarkers to detect metastasis, a technique not widely used in HNSCC treatment protocols.ResultsOur study revealed complex CTCs in metastatic HNSCC patients characterized by gene expression and mutational gene profiling via single-cell RNASeq (scRNASeq). These profiles confirmed molecular pathways inherent in CTCs, further validated by previous research.ConclusionThrough our research, we identified five dysregulated signaling pathways in CTCs, suggesting potential biomarker panels for HNSCC screening in situ tumors.

Nuclear miR-451a activates KDM7A and leads to cetuximab resistance in head and neck squamous cell carcinoma.

Cetuximab resistance has been a major challenge for head and neck squamous cell carcinoma (HNSCC) patients receiving targeted therapy. However, the mechanism that causes cetuximab resistance, especially microRNA (miRNA) regulation, remains unclear. Growing evidence suggests that miRNAs may act as "nuclear activating miRNAs" for targeting promoter regions or enhancers related to target genes. This study elucidates a novel mechanism underlying cetuximab resistance in HNSCC involving the nuclear activation of KDM7A transcription via miR-451a. Herein, small RNA sequencing, quantitative real-time polymerase chain reaction (qRT‒PCR) and fluorescence in situ hybridization (FISH) results provided compelling evidence of miR-451a nuclear enrichment in response to cetuximab treatment. Chromatin isolation via RNA purification, microarray analysis, and bioinformatic analysis revealed that miR-451a interacts with an enhancer region in KDM7A, activating its expression and further facilitating cetuximab resistance. It has also been demonstrated that the activation of KDM7A by nuclear miR-451a is induced by cetuximab treatment and is AGO2 dependent. Logistic regression analyses of 87 HNSCC samples indicated the significance of miR-451a and KDM7A in the development of cetuximab resistance. These discoveries support the potential of miR-451a and KDM7A as valuable biomarkers for cetuximab resistance and emphasize the function of nuclear-activating miRNAs.

Moderate SCRIB Expression Levels Correlate with Worse Prognosis in OPSCC Patients Regardless of HPV Status.

Head and neck cancers rank as the sixth most prevalent cancers globally. In addition to traditional risk factors such as smoking and alcohol use, human papillomavirus (HPV) infections are becoming a significant causative agent of head and neck cancers, particularly among Western populations. Although HPV offers a significant survival benefit, the search for better biomarkers is still ongoing. In the current study, our objective was to investigate whether the expression levels of three PDZ-domain-containing proteins (SCRIB, NHERF2, and DLG1), known HPV E6 cellular substrates, influence the survival of HNSCC patients treated by primary surgery (n = 48). Samples were derived from oropharyngeal and oral cancers, and HPV presence was confirmed by PCR and p16 staining. Clinical and follow-up information was obtained from the hospital database and the Croatian Cancer registry up to November 2023. Survival was evaluated using the Kaplan-Meier method and Cox proportional hazard regression. The results were corroborated through the reanalysis of a comparable subset of TCGA cancer patients (n = 391). In conclusion, of the three targets studied, only SCRIB levels were found to be an independent predictor of survival in the Cox regression analysis, along with tumor stage. Further studies in a more typical Western population setting are needed since smoking and alcohol consumption are still prominent in the Croatian population, while the strongest association between survival and SCRIB levels was seen in HPV-negative cases.

Molecular Aspects of Piperine in Signaling Pathways Associated with Inflammation in Head and Neck Cancer.

Piperine, an active plant alkaloid from black pepper (Piper nigrum), has several pharmacological effects, namely antioxidant, anti-inflammatory and immunomodulatory effects, which involve inhibiting molecular events associated with various stages of cancer development. The aim of this study was to investigate the molecular mechanisms of action of piperine in relation to its potential anticancer effect on head and neck cancer cells. Parameters related to neoplastic potential and cytokine, protein and gene expression were investigated in head and neck cancer cell lines (HEp-2 and SCC-25) treated with piperine. The results of the tests indicated that piperine modified morphology and inhibited viability and the formation of cell colonies. Piperine promoted genotoxicity by triggering apoptosis and cell cycle arrest in the G2/M and S phases. A decrease in cell migration was also observed, and there was decreased expression of MMP2/9 genes. Piperine also reduced the expression of inflammatory molecules (PTGS2 and PTGER4), regulated the secretion of cytokines (IFN-γ and IL-8) and modulated the expression of ERK and p38. These results suggest that piperine exerts anticancer effects on tumor cells by regulating signaling pathways associated with head and neck cancer.

HPV16 Phylogenetic Variants in Anogenital and Head and Neck Cancers: State of the Art and Perspectives.

HPV16 is responsible for approximately 60% and 90% of global HPV-induced cervical and oropharyngeal cancers, respectively. HPV16 intratype variants have been identified by HPV genome sequencing and classified into four phylogenetic lineages (A-D). Our understanding of HPV16 variants mostly derives from epidemiological studies on cervical cancer (CC) in which HPV16 B, C, and D lineages (previously named "non-European" variants) were mainly associated with high-grade cervical lesions and cancer. Although a predominance of HPV16 lineage A (previously named "European variants") has been observed in head and neck squamous cell carcinoma (HNSCC), epidemiological and in vitro biological studies are still limited for this tumor site. Next Generation Sequencing (NGS) of the entire HPV genome has deepened our knowledge of the prevalence and distribution of HPV variants in CC and HNSCC. Research on cervical cancer has shown that certain HPV16 sublineages, such as D2, D3, A3, and A4, are associated with an increased risk of cervical cancer, and sublineages A4, D2, and D3 are linked to a higher risk of developing adenocarcinomas. Additionally, lineage C and sublineages D2 or D3 of HPV16 show an elevated risk of developing premalignant cervical lesions. However, it is still crucial to conduct large-scale studies on HPV16 variants in different HPV-related tumor sites to deeply evaluate their association with disease development and outcomes. This review discusses the current knowledge and updates on HPV16 phylogenetic variants distribution in HPV-driven anogenital and head and neck cancers.

Integrating bulk and single-cell sequencing reveals metastasis-associated CAFs in head and neck squamous cell carcinoma.

AIMS: Cancer-associated fibroblasts (CAFs) have been shown to promote the metastasis of head and neck squamous cell carcinoma (HNSCC), but the underlying mechanisms remain unclear. The purpose of this study is to identify gene in CAFs that are associated with metastasis and to preliminarily validate its impact on the metastasis of HNSCC. MATERIALS AND METHODS: Scissor analysis was utilized to process single-cell and bulk RNA sequencing datasets, identifying genes associated with the metastasis of HNSCC through differential gene expression analysis. A risk model was constructed using LASSO regression analysis. Quantitative real time-PCR and Western blot were employed to measure mRNA and protein expressions, respectively. Multiplex immunohistochemistry (mIHC) was used to assess protein expression in CAFs. siRNA was utilized to achieve gene knockdown. CCK-8 and Transwell assays were employed to evaluate the biological characteristics of HNSCC cells. KEY FINDINGS: Compare to the nonmetastatic primary CAFs (nmCAFs), tissue inhibitors of metalloproteinase-1 (TIMP1) was founded to be overexpressed in the cells and tissues of metastatic primary CAFs (mCAFs). Knocking down TIMP1 in CAFs can signifucantly inhibit the proliferation, invasion, and migration of HNSCC cells. SIGNIFICANCE: CAFs facilitate HNSCC cell metastasis by upregulating TIMP1, highlighting TIMP1 as a potential therapeutic target in HNSCC metastasis management.