Head And Neck Squamous Cell Carcinoma Research Articles

Abstract C009: MK2 knockout and radiation enhances immune cell influx in a mouse model of HPV+ head and neck squamous cell carcinoma

Abstract Introduction: HPV mediated head and neck squamous cell carcinoma (HNSCC) has an immunosuppressive microenvironment which contributes to local and distant failures. We have previously shown that MAPKAPK2 (MK2) inhibition (MK2i) in HNSCC results in improved response to irradiation (RT). MK2i was synergistic with RT resulting in better control than monotherapy. To understand the mechanism behind the improvement of RT in MK2i treated mice we tested the hypothesis that MK2 ablation can enhance the radiotherapy mediated immunogenic response in a solid tumor. Methods: We used CRISPR gene editing to knockout the MK2 gene in the highly metastatic murine cell line, MLM3 (KO). We implanted tumors into c57bl6 and NSG mice and compared tumor growth compared to wild type (WT) with and without radiation. At end point, tumors were excised, digested and immunophenotyped utilizing labelled antibodies and flow cytometry. Before immunophenotyping, 8 mgs of tumor were cut off and incubated in media for 24 hours to assess cytokine release by cytokine array analysis. Results: We found that the differences in tumor growth between WT and KO cells in c57bl6 mice were significantly greater than those seen in NSG mice. Survival studies with c57bl6 mice implanted with WT or KO tumors with and without RT showed that MLM3 KO implanted mice had significantly greater survival (58.5 days) compared to WT (35.5 days). WT tumors treated with RT improved median overall survival with the WT + RT group surviving longer than WT (56 days) and the MK2 KO + RT had the longest survival overall (65 days). Immunophenotyping WT v KO tumors grown in c57bl6 mice showed an increase in CD45 cells in the KO tumors compared to WT. The cells that were increased in number in the KO tumors were labelled by Ly6G (neutrophils), F4/80 (macrophages), CD14+MD11c (dendritic cells), CD4 (Th), CD8 (Tc), CD3+NK1.1 (NKt) and NK1.1 (NK cells). Irradiating the tumors accentuated the influx of immune cells causing a greater influx of CD45 cells at 3 days post-RT which included increases in F4/80+CD80 (M1 macrophages), CD14 (monocytes), CD11c+MHCII, NK1.1, NK1.1+CD3 and CD4 cells. However, the influx of CD8 cells were reduced at 3 days. At 8 days post RT, many cell types remained elevated in the KO tumors compared to wildtype and there was a partial recovery of CD8 cell influx. However, there was also an increase in immune suppressor cells into the tumors including Ly6C+arginase (M-MDSCs), Ly6C+arginase (PMN-MDSCs) and CD4+T-bet (Th1) cells. The cytokine analysis showed that six cytokines were differentially secreted from tumors: Dkk-1, IL-2, IGFBP-5, IL-3, IL-17a and CD14. All these cytokines were suppressed in the KO with respect to the WT tumors. Conclusion: Here we show evidence that genetic ablation of MK2 in a mouse model of HPV mediated HNSCC results in an increase in immune cells infiltrate into tumors. Irradiation enhances this difference by stimulating a greater influx of immune cells. These data suggest that tumoral MK2 may aid in the immunosuppression of tumors in HNSCC. Citation Format: Deri Morgan, Colby Spiess, Alyssa Schmidt, Dakota D.D. Okuwone, Harmony Saunders, Chris E. Lominska, Mary A. Markiewicz, Yelder Tonia, Devin Shrock, Yuting Lin, Hao Gao, Gregory N Gan. MK2 knockout and radiation enhances immune cell influx in a mouse model of HPV+ head and neck squamous cell carcinoma [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr C009.

Abstract C010: Tumor MK2 drives tumor progression and an immunosuppressive microenvironment in head and neck squamous cell carcinoma

Abstract Background: Head and neck squamous carcinoma (HNSCC) results in poor patient outcomes driven primarily by locoregional and distant metastatic tumor spread. We have demonstrated that highly phosphorylated/active MAPKAPK-2 (MK2) is a poor prognostic factor in HNSCC patients. MK2 is associated with the expression of pro-inflammatory cytokines that are linked with creating a pro-tumorigenic microenvironment. Nevertheless, how MK2 contributes to HNSCC development has not been established. In this study, we aimed to identify the effect of MK2 on cancer progression, immune infiltration, and cytokine secretion. Method: To assess the effect of tumor MK2 in vivo, we used CRISPR-Cas9 to knock out (KO) MK2 in a metastatic murine HNSCC cell line, Ly2, and orthotopically implanted wildtype (WT) or MK2 KO cells into the floor-of-mouth of Balb/c mice. At the endpoint of the experiment, the tumors were excised, and myeloid and lymphocyte immune profiling was done via flow cytometry. Mouse lungs and cervical lymph nodes were dissected, paraffin-fixed, sectioned, and H&E stained, and the presence/quantity of metastatic foci was evaluated by a blinded board-certified pathologist. We broadly evaluated the tumor secretome via a 105-cytokine dot blot array using 8 mg of the same resected tumor sample and performed densitometric analysis comparing WT and KO tumors. Results: Loss of MK2 significantly reduced primary tumor growth, as well as lymph node and lung metastasis, compared to WT tumors. Tumor immunophenotyping by flow cytometry revealed that MK2 KO tumors had increased overall immune cell (CD45+) infiltration, but decreased quantities of immunosuppressive neutrophils (CD11b+Ly6G+Arg1+Ly6C-) and a shift in macrophage polarity favoring M1 (anti-tumor) macrophages (CD11b+Ly6G-F4-80+CD80+). In addition, there were increased quantities of anti-tumor immune cells including natural killer (NK)-T, CD4+, and CD8+ T cells in the MK2-KO tumors, while the proportion of CD4+CD25+ Tregs and exhausted CD8 T cells (CD8+PD1+) was decreased compared to WT tumors. Furthermore, cytokine array analysis revealed that secreted levels of several cytokines, including CXCL1, CXCL2, GM-CSF, G-CSF, IL-1alpha, and IL-6, were significantly lower in MK2 KO tumors compared to WT tumors. Conclusion: These results show that tumoral MK2 signaling promotes tumor growth, metastasis, immunosuppressive inflammation, and pro-tumorigenic cytokine release which substantiates future therapeutic targeting of this pathway. Citation Format: Dakota D.D. Okwuone, Deri Morgan, Alyssa Schmidt, Devin Shrock, Yuting Lin, Hao Gao, Sufi M. Thomas, Gregory N. Gan. Tumor MK2 drives tumor progression and an immunosuppressive microenvironment in head and neck squamous cell carcinoma [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr C010.

Survival prediction in patients with head and neck squamous cell carcinoma and novel mechanistic insights of S100A8/A9.

S100A8/A9, an innate immune protein, significantly regulates inflammatory processes and immune responses. While S100A8/A9 has been linked to various diseases, its association with head and neck squamous cell carcinoma (HNSCC) remains unclear. Samples from the Cancer Genome Atlas (TCGA) were categorized into groups with low and high expression of S100A8/A9. R software, Sangerbox, UALCAN, GEPIA2, STRING, Cytoscape, TCGC Data Portal, miRcode, OncomiR and ENCORI databases were used to comprehensively study the expression, interactome and mutational profiles of S100A8/A9 and associated mechanism in HNSCC. The proteins S100A8/A9 were found to be associated with processes of 'epithelium development', 'regulating pluripotency of stem cells' and 'regulation of immune system'. The most frequent mutation observed in the S100A8 protein was E93K (3/37, MU4401889), while for the S100A9 protein, it was R10C (4/37, MU4633862). Furthermore, the group expressing high levels of S100A8/A9 showed increased infiltration by dendritic cells and neutrophils, but decreased infiltration by M2 macrophages, compared to the group with low S100A8/A9 expression. S100A8/A9 was also found to interact with a variety of mRNA transcripts, several of which were involved in initiation and progression of HNSCC. Through LASSO-Cox method, 20 genes (CALML5, MSX1, FZD3, STC2, SLC2A3, TMEM198B, DYNC1I1, SPHK2, ALMS1.IT1, SPPL2B, PDGFA, BCORL1, TEX101, SGCE, DNAJC12, RRN3P1, HOXB9, TMEM150C, METTL7B and PSPN) were screening to construct a prognostic model to distinguish favorable and poor prognosis of HNSCC patients. Besides, our prognostic model was also validated in GSE41613 cohort. S100A8/A9 may be a promising marker for the diagnostic and prognostic assessment of the HNSCC patients. Based on these insights, we have devised a new classification model for HNSCC, which has the potential to enhance the management and personalized treatment of HNSCC patients. The model should also be further optimized through the expansion of sample size and implemented experimental studies in future research.

Tumor suppressor ACER1 correlates with prognosis and Immune Infiltration in head and neck squamous cell carcinoma.

Head and neck squamous cell carcinoma (HNSCC) is notorious for poor prognoses, and effective biomarkers are urgently needed for early diagnosis of HNSCC patients. We investigate the role of alkaline ceramidase 1 (ACER1) and its relationship with immune infiltration in HNSCC. The differential expression and clinical prognostic significance of ACER1 in HNSCC patients are explored using bioinformatics methods and verified in human HNSCC samples. Genetic mutation, DNA methylation and drug sensitivity linked with ACER1 are examined. The potential biological function of ACER1 co-expression genes is assessed, and a series of functional assays are performed on ACER1in vitro. The results comprehensively reveal a relationship between ACER1 and immune infiltration in HNSCC patients. ACER1 expression is significantly downregulated in HNSCC tissues and closely correlated with better prognoses for HNSCC patients, and this prognostic significance is determined by distinct clinical characteristics. Genetic alteration and promoter hypomethylation of ACER1 are involved in progression of HNSCC, and ACER1 expression is significantly related to several drug sensitivities. Functional analysis shows that ACER1 co-expression genes are mainly enriched in the sphingolipid signaling pathway associated with inhibition of tumorigenesis, leading to better prognoses for HNSCC patients. In vitro, ACER1 overexpression inhibits proliferation and migration, induces apoptosis, and promotes adhesion of Fadu and SCC9 cells. In addition, high ACER1 expression is closely linked with infiltration levels of immune cells, and strongly associated with biomarkers of immune cells in HNSCC, suggesting the important role of ACER1 in regulating tumor immunity in HNSCC patients. In summary, ACER1 may be a useful indicator for diagnosis and prognosis, and may regulate immune infiltration in HNSCC patients, thus promising targeted immunotherapy for HNSCC.

Abstract B031: Immune cell composition in surgical drain fluid as a novel prognostic marker in head and neck squamous cell carcinoma

Abstract Background: Head and neck squamous cell carcinoma (HNSCC) is the sixth most common malignancy globally, and the vast majority of cases are treated with primary surgical resection and adjuvant therapy. Our group has pioneered the use of HNSCC circulating tumor DNA (ctDNA) in surgical effluent collected postoperatively from surgical drains (surgical drain fluid, SDF) as a novel proximal bioanalyte for measuring minimal residual disease after surgery. We now profile the immune cell composition of SDF compared to paired peripheral blood mononuclear cells (PBMCs), and correlate SDF immune cell profiles with clinical variables and oncologic outcomes in HNSCC. Method: SDF and peripheral venous blood were collected 24 hours postoperatively from 58 HNSCC patients, including 11 HPV (+) and 47 HPV (-) patients undergoing standard of care surgical resection, lymph node dissection, and adjuvant therapy. Freshly collected SDF cells and PBMCs were cryopreserved until profiling by multicolor flow cytometry for respective leukocyte compositions. Analyses were used to define the following viable CD45+ leukocyte subsets: total T cells, CD4 T-cells CD8 T-cells, Treg cells, B-cells, non- classical monocytes, classical monocytes, natural killer (NK) cells, classical dendritic cells (cDC), plasmacytoid DC (pDC), macrophages, and monocytic myeloid-derived suppressive cells (MDSCs). Immune cell percentages were correlated with clinical characteristics and cancer recurrence. Results: CD45+ leukocytes comprised >99.5% of SDF cells, with very few EPCAM+ tumor cells (< 10^-4). HPV status did not significantly affect SDF immune cell composition, and no significant differences were noted by tumor site (larynx, oral cavity, oropharynx), or extracapsular lymph node extension. Among 13 HPV (-) HNSCC patients with paired peripheral blood drawn concurrently, SDF had a higher proportion of B-cells(16.8% vs. 9%, p=0.044), NK cells(56% vs. 12%, P<0.001), monocytes(14% vs. 1%, P<0.001), and macrophages(3.1% vs. 0.46%, P<0.001) compared to PBMCs, and a lower proportion of CD4+ T cells(1% vs. 24%, P<0.001), CD8+ T cells(0.6% vs. 18%, P<0.001), MDSCs(2.1% vs. 3.4%, P=0.029), and pDCs(0.1% vs. 0.2%, P=0.014). HPV (-) HNSCC patients that went on to recur (n=9) had a significantly higher proportions of SDF monocytes (total, classical, and non- classical) and CD56dimCD16+ NK cells (all P<0.001) compared to non-recurrent patients (n=38). Patients who went on to recur also had a significantly lower proportion of SDF B-cells (P<0.001), CD56bright NK cells(P=0.01), and macrophages (P=0.018) compared to non- recurrent cases. No significant differences were noted with respect to proportions of CD3+, CD4+, CD8+ T-cells, DC, and MDSC cells. Conclusion: SDF from HNSCC patients contains unique immune cell populations and may provide new insights into postoperative tumor immunity. Differences in SDF immune cell composition by oncologic outcome in patients that go on to recur, highlighting potential prognostic and predictive applications of SDF immune cell profiling for adjuvant therapy decision-making. Citation Format: Zhongping Xu, Noah Earland, Lucien Khalil, Lazar Vujanovic, Danny Azmi Elias, Riyue Bao, Jason J. Luke, Aadel A. Chaudhuri, Jose P. Zevallos. Immune cell composition in surgical drain fluid as a novel prognostic marker in head and neck squamous cell carcinoma [abstract]. In: Proceedings of the AACR Special Conference: Liquid Biopsy: From Discovery to Clinical Implementation; 2024 Nov 13-16; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(21_Suppl):Abstract nr B031.

Abstract B057: Base-error model (BEM) for improved detection of ctDNA in lymph samples of HPV-negative head and neck cancer patients

Abstract Introduction: Previously we demonstrated that ctDNA present in lymphatic exudate collected via surgical drains (“lymph”) outperformed plasma for detecting minimal residual disease (MRD) in head and neck squamous cell carcinoma (HNSCC) patients through a targeted sequencing (TS) approach. However, artifacts introduced during library preparation and sequencing remain challenges to sensitive low allelic fraction mutation detection. To enhance the performance of the TS approach, we characterized the background noise in lymph samples and developed a base-error model (BEM) that reduces sequencing artifacts and maximizes ctDNA signal. Methods: Lymph and blood were collected from 44 HPV-negative HNSCC patients postoperatively at 24 hours along with resected tumor. Cell-free DNA was extracted from lymph and sequenced using a custom TS panel with unique molecular identifiers (UMI). Somatic mutations were identified by tumor and blood exome sequencing (200x). Five patients had <2 mutations in tumor and were excluded. Two patients were censored due to lack of clinical data, yielding 17 patients with disease recurrence (REC) and 20 with no evidence of disease (NED) with >1 year of follow-up. Tumor-specific variants were force-called in lymph using a custom pipeline. A BEM of each tumor variant was built using a series of high-quality lymph reference samples to quantify the background noise. BEM was fit by Weibull distribution if more than 5 non-zero non-reference alleles were observed at a tumor variant position across the reference samples. Otherwise, Gaussian distribution was used to fit BEM. Force-called variants were considered artifacts if the variant allele fraction (VAF) was not greater than BEM cutoff controlled by false discovery rate. Patients were considered MRD positive if the mean VAF was greater than the estimated limit of detection. The Kaplan-Meier (KM) estimator with log-rank test and Cox proportional-hazards model were used for survival analyses. Results: Background noise was observed in reference lymph samples across all 12 nucleotide substitution classes. Out of 299 single nucleotide variants (SNVs), 94 were determined as artifacts by BEM. Among the artifacts, 77 were C/G to A/T mutations, indicating that the majority of recurrent background artifact in TS is likely the result of oxidative damage. The artifacts had VAFs ranging from 0.004% to 0.12% with median of 0.02%. Incorporation of BEM in lymph TS showed significantly improved specificity (sensitivity (SN) = 71%, specificity (SP) = 65%; p = 0.027, Hazard ratio (HR) = 3.07) compared to the same cohort without BEM (SN = 76%, SP = 30%, p = 0.60, HR = 1.34). Conclusions: BEM is a sensitive and robust method to improve ctDNA detection accuracy in TS. We demonstrated its utility in improving recurrence prediction in a HNSCC cohort. Given its advantages, we envision that BEM will prove useful as a general strategy for deep sequencing applications requiring precise digital quantification of low frequency alleles in TS. Citation Format: Zhuosheng Gu, Maciej Pacula, Seka Lazare, Noah Earland, Marra S. Francis, Adam Harmon, Megan Long, Aadel A. Chaudhuri, Jose P. Zevallos, Wendy Winckler. Base-error model (BEM) for improved detection of ctDNA in lymph samples of HPV-negative head and neck cancer patients [abstract]. In: Proceedings of the AACR Special Conference: Liquid Biopsy: From Discovery to Clinical Implementation; 2024 Nov 13-16; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(21_Suppl):Abstract nr B057.

Abstract PR002: The clinical relevance of circulating tumor cell size in head and neck squamous cell carcinoma patients

Abstract Circulating tumor cells (CTCs) play a critical role in the metastatic process of cancer and are widely recognized as important biomarkers that provide valuable information related to tumor characteristics. While most research to date has focused on the biological markers and molecular properties of CTCs, their physical characteristics, particularly size, have been relatively underexplored. However, recent studies suggest that smaller CTCs exhibit enhanced tumor- initiating and metastatic abilities compared to larger CTCs. This indicates that CTC size is not merely a physical trait but may directly influence the invasiveness and metastatic potential of tumors. Such findings suggest that CTC size could be an important indicator for predicting tumor malignancy and provide a new perspective on understanding cancer progression and metastasis. As such, there is a growing emphasis on research that considers the size of CTCs. In this study, it was speculated whether CTC size holds clinical significance in patients with head and neck squamous cell carcinoma (HNSCC). The study was involved with 20 HNSCC patients, analyzing the morphological characteristics of CTCs collected from blood samples before and after treatment, while exploring the potential for monitoring treatment response. Our results found that CTCs were detected 20% more frequently in oropharyngeal cancer (OPC) patients compared to non-OPC patients. This is likely due to the rich vascularity in the oropharyngeal region, which may facilitate greater entry of CTCs into the bloodstream. Additionally, the cell size (23.9 μm in average) and nuclear size (16.4 μm in average) of HPV-positive patients were 32% and 10% larger, respectively, than those of HPV-negative patients (cell size: 18.1 μm; nuclear size: 12.60 μm). This suggests that the sizes of CTC and their nuclei may be associated with HPV status, which is presumed to be due to HPV causing disruptions in the cell cycle. In addition, we could successfully cultivate the CTCs obtained from HPV-positive patients with relatively smaller CTCs for 30 days, predicting that small CTCs have affordable for CTC culture. In conclusion, this study confirms that the physical characteristics of CTCs, particularly size, are linked to HPV infection status in HNSCC patients. CTC- and nucleus- size are closely related to tumor characteristics, demonstrating the potential for developing diagnostic and prognostic tools based on these physical traits. Although more in-depth research is required, poor prognosis in HPV- positive patients may also be related to the physical characteristics of CTCs. Citation Format: Hyeongjung Woo, Hyun Young Shin, So Yeon Oh, Sun Min Lee, Minseok S. Kim. The clinical relevance of circulating tumor cell size in head and neck squamous cell carcinoma patients [abstract]. In: Proceedings of the AACR Special Conference: Liquid Biopsy: From Discovery to Clinical Implementation; 2024 Nov 13-16; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(21_Suppl):Abstract nr PR002.

Abstract B048: Microfluidic isolation of immune cell-derived extracellular vesicles in head and neck cancer patients on immune-checkpoint blockade

Abstract Background: Immune-checkpoint blockade (ICB), with or without chemotherapy, is the standard of care for recurrent/metastatic head and neck squamous cell carcinoma (HNSCC). However, only a minority of patients get clinical benefit from it. The combined expression of PD-L1 in a tumor section is currently the only biomarker approved for response prediction. Yet, its invasive nature and suboptimal predictive performance underscores the need for new, non- invasive surrogates of immune activity in patients undergoing ICB. Extracellular vesicles (EVs) carry key molecules critical for cell-cell communication and have the potential to be used as a non-invasive, real-time biomarker of systemic immune activity, essential for success in ICB- based therapy. Methods: We used a multichannel, microfluidic device that employs an immune- affinity approach, ‘herringbone chip’ (EVHB-Chip), to retrospectively isolate EVs from twelve HNSCC patients before and after the first cycle of ICB. One mL of plasma was used per patient per time point. For each patient, two devices were serially used, with each sample continuously following through each chip in a non-destructive manner—the first device aimed to isolate B cell EVs (antibodies against CD19 and CD20). The second device was optimized to capture T cell EVs (against CD274/PD-L1). Digital-droplet PCR was performed after EVs were isolated to detect the RNA transcripts in the EV cargo. Serial sampling was performed for six out of the twelve patients. Response assessment was conducted via RECIST1.1 criteria or clinical evaluation. Results: Most of our cohort was male 7/12 (57%) and had oral cavity 4/12 (33%) or oropharynx 4/12 (33%) tumors. Additionally, 11/12 (91%) patients received ICB monotherapy. Most of the cohort had a PD-L1 ≤ 1 (7/12; 58%), 7/12 patients experienced disease progression (PD), 4/12 experienced stable disease (SD), and one patient had a partial response (PR). Most of the RNA signal in pre-ICB samples was obtained from CD20 (12/12; 100%), followed by CD45 (10/12; 83%), CD19 (9/12; 75%), and CD274/PD-L1 (5/12; 41%). No difference was found in the RNA signal pre-ICB between responders and non-responders (p=0.1). For the patients with serial sampling available, the signal from CD274/PD-L1 increased after one infusion of ICB in 4/6 patients and remained negative in one. A trend towards a high amount of T cell-derived EVs was observed for the entire cohort (p=0.07; p=0.08) when comparing the amount of RNA via our EV marker (GAPDH, ACTB) between T and B cell devices. Patients with higher than 11.4/mL copies of CD19 (median value for the cohort) in the pre-ICB plasma sample tended to have a higher overall survival (HR 0.26, 95% CI: 0.06-1.13; p-value: 0.05) and progression-free survival (HR 0.28, 95% CI: 0.07-1.16; p-value: 0.06). Conclusion: The EVHB-Chip allowed for the detection and profiling of T and B cell-derived EVs in pre-ICB plasma samples of HNSCC patients undergoing ICB in this pilot cohort. Higher CD19 signal pre-ICB could potentially impact response and survival outcomes in ICB-based therapies. Citation Format: Andrew R. Levy, Daniel A Ruiz Torres, Uma Paithankar, Raheel Ahmad, Daniel C Rabe, Daniel L Faden, Shannon L Stott. Microfluidic isolation of immune cell-derived extracellular vesicles in head and neck cancer patients on immune-checkpoint blockade [abstract]. In: Proceedings of the AACR Special Conference: Liquid Biopsy: From Discovery to Clinical Implementation; 2024 Nov 13-16; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(21_Suppl):Abstract nr B048.

A pyroptosis-related lncRNA risk model for the prediction of prognosis and immunotherapy response in head and neck squamous cell carcinoma

BackgroundRecent research has highlighted pyroptosis as a key factor in cancer progression. This study aims to explore the association between pyroptosis-related signatures and overall survival (OS) in head and neck squamous cell carcinoma (HNSC) and develop a pyroptosis-related long non-coding RNA (lncRNA) risk model to predict prognosis and response to immunotherapy in HNSC.MethodsWe extracted expression data for 18 pyroptosis-related genes and identified lncRNA probes specific to HNSC by using datasets from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA). Consensus clustering was performed to categorize HNSC patients into distinct subtypes. A six-lncRNA risk score model was constructed through univariate and least absolute shrinkage and selection operator (LASSO) Cox regression analyses. We evaluated the predictive ability of the lncRNA model for patients’ survival and immunotherapy response. Gene expression was evaluated using immunohistochemistry (IHC) and Reverse Transcription Quantitative Polymerase Chain Reaction (RT-qPCR).ResultsOur analysis revealed two distinct pyroptosis-related subtypes in HNSC patients, Cluster A and Cluster B. Notably, patients in Cluster B exhibited significantly poorer overall survival compared to those in Cluster A. Through differential expression analysis, we identified six lncRNAs (AC002331.1, CTA-384D8.35, RP11-291B21.2, AC006262.5, RP1-27K12.2, and RP11-54H7.4) that were differentially expressed between these clusters. A 6-lncRNA risk score model was developed, which successfully stratified patients into high- and low-risk groups with distinct overall survival outcomes. Validation using RT-qPCR confirmed the differential expression of these six lncRNAs in HNSC tumor tissues compared to adjacent normal tissues, we found that the expression of CTA-384D8.35 was significantly increased in the tumor group (t=-6.203, P<0.001). Furthermore, the 6-lncRNA risk score model demonstrated a significant association with patient response to immunotherapy, with the low-risk group exhibiting a higher objective response rate to immune checkpoint blockade (ICB) therapy and longer survival compared to the high-risk group.ConclusionOur study underscores the role of pyroptosis signatures in HNSC prognosis and identifies two distinct pyroptosis subtypes with differing survival outcomes. The six-lncRNA risk score model offers a valuable tool for predicting patient prognosis and potential benefits from ICB therapy. These findings highlight the importance of pyroptosis and associated lncRNAs in the tumor microenvironment, paving the way for novel targeted therapies in HNSC.

Comprehensive analysis of the relationship between RNA modification writers and immune microenvironment in head and neck squamous cell carcinoma.

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide. Four types of RNA modification writers (m6A, m1A, A-I editing, and APA) are widely involved in tumorigenesis and the TME. We aimed to comprehensively explore the role of the four RNA modification writers in the progression and immune microenvironment of HNSCC. We first obtained transcription profile data and transcriptional variation of the four types of RNA modification writers from The Cancer Genome Atlas (TCGA) database. HNSCC patients in TCGA dataset were divided into different clusters based on the four types of RNA modification writers. Univariate Cox and Least absolute shrinkage and selection operator (LASSO) analyses were performed to conduct a Writer-score scoring system, which was successfully verified in the GSE65858 dataset and our clinical sample dataset. Finally, we evaluated the relationship between different RNA modification clusters (Writer-score) and immunological characteristics of HNSCC. Two different RNA modification clusters (A and B) were obtained. These RNA modification clusters (Writer-score) were strongly associated with immunological characteristics (immunomodulators, cancer immunity cycles, infiltrating immune cells (TIICs), inhibitory immune checkpoints, and T cell inflamed score (TIS)) of HNSCC. This study identified two different RNA modification clusters and explored the potential relationship between RNA modification clusters (Writer-score) and immunological characteristics, offering a new theoretical basis for precision immunotherapy in patients with HNSCC.

Type I Interferon Drives a Cellular State Inert to TCR-Stimulation and Could Impede Effective T-Cell Differentiation in Cancer.

Head and neck squamous cell carcinoma (HNSCC) is linked to human papillomavirus (HPV) infection. HPV-positive and HPV-negative HNSCC exhibit distinct molecular and clinical characteristics. Although checkpoint inhibitors have shown efficiency in recurrent/metastatic HNSCC, response variability persists regardless of HPV status. This study aimed to explore the CD8+ T-cell landscape in HPV-negative HNSCC. We performed simultaneous single-cell RNA and TCR sequencing of CD8+ tumor-infiltrating lymphocytes (TILs) from treatment-naïve HPV-negative HNSCC patients. Additionally, cells were stimulated ex vivo, which allowed for the tracking of clonal transcriptomic responses. Our analysis identified a subset of CD8+ TILs highly enriched for interferon-stimulated genes (ISG). TCR analysis revealed ISG cells are clonally related to a population of granzyme K (GZMK)-expressing cells. However, unlike GZMK cells, which exhibited rapid effector-like phenotypes following stimulation, ISG cells were transcriptionally inert. Additionally, ISG cells showed specific enrichment within tumor and were found across multiple tumor entities. ISG-enriched CD8+ TILs are a consistent feature of various tumor entities. These cells are poorly understood but possess characteristics that may impact antitumor immunity. Understanding the unique properties and functionality of ISG cells could offer innovative treatment approaches to improve patient outcomes in HPV-negative HNSCC and other cancer types.

Head and Neck Squamous Cell Carcinoma: Insights from Dual-Energy Computed Tomography (DECT)

Head and neck cancer represents the seventh most common neoplasm worldwide, with squamous cell carcinoma being the most represented histologic variant. The rising incidence of the neoplastic pathology of this district, coupled with the drastic changes in its epidemiology over the past decades, have posed significant challenges to physicians worldwide in terms of diagnosis, prognosis, and treatment. In order to meet these challenges, a considerable amount of effort has been spent by the authors of the recent literature to explore new technologies and their possible employment for the better diagnostic and prognostic definition of head and neck squamous cell carcinoma (HNSCC). Among these technologies, a growing interest has been gathering around the possible applications of dual-energy computed tomography (DECT) in head and neck pathology. Dual-energy computed tomography (DECT) utilizes two distinct X-ray energy spectra to obtain two datasets in a single scan, allowing for material differentiation based on unique attenuation profiles. DECT offers key benefits such as enhanced contrast resolution, reduced beam-hardening artifacts, and precise iodine quantification through monochromatic reconstructions. It also creates material decomposition images, like iodine maps, aiding in tumor characterization and therapy assessment. This paper aims to summarize recent findings on the use of DECT in HNSCC, providing a comprehensive overview to aid further research and exploration in the field.

PRMT5/WDR77 Enhances the Proliferation of Squamous Cell Carcinoma via the ΔNp63α-p21 Axis

Protein arginine methyltransferase 5 (PRMT5) is a critical oncogenic factor in various cancers, and its inhibition has shown promise in suppressing tumor growth. However, the role of PRMT5 in squamous cell carcinoma (SCC) remains largely unexplored. In this study, we analyzed SCC patient data from The Cancer Genome Atlas (TCGA) and the Cancer Dependency Map (DepMap) to investigate the relationship between PRMT5 and SCC proliferation. We employed competition-based cell proliferation assays, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assays, flow cytometry, and in vivo mouse modeling to examine the regulatory roles of PRMT5 and its binding partner WDR77 (WD repeat domain 77). We identified downstream targets, including the p63 isoform ΔNp63α and the cyclin-dependent kinase inhibitor p21, through single-cell RNA-seq, RT-qPCR, and Western blot analyses. Our findings demonstrate that upregulation of PRMT5 and WDR77 correlates with the poor survival of head and neck squamous cell carcinoma (HNSCC) patients. PRMT5/WDR77 regulates the HNSCC-specific transcriptome and facilitates SCC proliferation by promoting cell cycle progression. The PRMT5 and WDR77 stabilize the ΔNp63α Protein, which in turn, inhibits p21. Moreover, depletion of PRMT5 and WDR77 repress SCC in vivo. This study reveals for the first time that PRMT5 and WDR77 synergize to promote SCC proliferation via the ΔNp63α-p21 axis, highlighting a novel therapeutic target for SCC.

Hypoxia combined with radiation reverses migration and invasion of head and neck squamous cell carcinoma by remodeling extracellular vesicle‐mediated transfer of miR‐23b‐5p from cancer‐associated fibroblasts

AbstractBackgroundCancer‐associated fibroblasts (CAFs), the main matrix components in the tumor microenvironment (TME), play a crucial role in tumor progression. Extracellular vesicles (EVs) as main mediators in intercellular communication can be regulated by hypoxia or radiation.MethodsCAFs were extracted from head and neck squamous cell carcinoma (HNSCC) tissues and CAF‐derived EVs were collected by ultracentrifugation. Bioinformatics analysis determined the role of poly (U)‐specific endonuclease (ENDOU) on HNSCC progression and confirmed that ENDOU inhibited HNSCC progression by overexpressing ENDOU in HNSCC. Dual‐luciferase activity report assay confirmed that miR‐23b‐5p was involved in the regulation of ENDOU expression. The migration and invasion of HNSCC cells were verified by transwell assay. Furthermore, tumor‐bearing mouse models were used to demonstrate the potential of EVs loaded with miR‐23b‐5p in HNSCC to promote tumor progression.ResultsOur results showed that ENDOU was downregulated in HNSCC and inhibited HNSCC migration and invasion. Hypoxia and radiotherapy reversed CAF‐derived EVs to promote migration and invasion of HNSCC. Mechanically, hypoxia and radiation downregulated miR‐23b‐5p in CAF‐derived EVs and then restored ENDOU expression in HNSCC. Finally, CAF‐derived EVs carrying miR‐23b‐5p promoted the progression of HNSCC cells in vivo by regulating ENDOU expression.ConclusionThis study demonstrated that hypoxia combined with radiation reverses the promoting effect of CAFs on HNSCC migration and invasion by reducing the delivery of miR‐23b‐5p by CAF‐derived EVs to decrease the inhibitory effect of ENDOU expression in HNSCC. The results provide a new perspective for better understanding the role of stromal components in TME in tumor regulation. Furthermore, the results provide a strong basis for the possibility of ENDOU as a biomarker for HNSCC.

Unveiling Biomarkers in Head and Neck Squamous Cell Carcinoma through Bioinformatics: The Role of SPP1 and KRT78

Head and neck squamous cell carcinoma (HNSCC) is the most common form of head and neck cancer, ranking sixth in global cancer incidence. Identifying molecular drivers of tumorigenesis and metastasis is essential for early detection and treatment. This study analyzed gene expression profiles from three datasets (GSE6791, GSE29330, and GSE58911) to identify differentially expressed genes (DEGs) in HNSCC. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were employed to functionally annotate these DEGs. A protein–protein interaction (PPI) network was constructed for selecting hub genes using the STRING database. Finally, hub gene and protein expression levels were evaluated in patients with HNSCC, along with their association with overall survival. Our analysis identified twenty-eight co-DEGs comprising eight up-regulated and twenty down-regulated genes, primarily involved in extracellular matrix (ECM) organization, proteolysis, ECM disassembly, and keratinization processes. Furthermore, the PPI network revealed eight hub genes based on their high degree of connectivity. Notably, SPP1 demonstrated up-regulation, while KRT78 was down-regulated in HNSCC. Remarkably, the expression levels of these hub genes correlated with tumor grade, clinical cancer stage, and poor prognosis in HNSCC. Our findings hold significant clinical potential for early diagnosis and the development of novel therapeutic targets for patients with HNSCC.

Near-Infrared Activatable Copper Nanoplatforms Synergize with the 5-Azacytidine Prodrug to Potentiate Cuproptosis.

Cuproptosis, a newly discovered cell death modality, is gaining recognition for its crucial role in antitumor therapy. Here, we demonstrated that Ferredoxin 1 (FDX1), a key gene involved in cuproptosis, is negatively correlated with malignancy and T-cell exhaustion in head and neck squamous cell carcinoma (HNSCC). Based on these findings, we developed near-infrared (NIR) light-controlled nanoparticles (NPs), CuD@PM, which can selectively deliver copper to HNSCC cells and induce cuproptosis in the presence of microneedles loaded with triacetylated azacitidine (TAc-AzaC) and 808 nm laser irradiation. Intravenous administration of these NPs significantly suppressed tumor growth in HNSCC animal models and enhanced the antitumor immune response. The NIR-controlled activation of cuproptosis offers great potential as a safe, targeted, and image-guided antitumor therapy for HNSCC.

Near‐Infrared Activatable Copper Nanoplatforms Synergize with the 5‐Azacytidine Prodrug to Potentiate Cuproptosis

AbstractCuproptosis, a newly discovered cell death modality, is gaining recognition for its crucial role in antitumor therapy. Here, we demonstrated that Ferredoxin 1 (FDX1), a key gene involved in cuproptosis, is negatively correlated with malignancy and T‐cell exhaustion in head and neck squamous cell carcinoma (HNSCC). Based on these findings, we developed near‐infrared (NIR) light‐controlled nanoparticles (NPs), CuD@PM, which can selectively deliver copper to HNSCC cells and induce cuproptosis in the presence of microneedles loaded with triacetylated azacitidine (TAc‐AzaC) and 808 nm laser irradiation. Intravenous administration of these NPs significantly suppressed tumor growth in HNSCC animal models and enhanced the antitumor immune response. The NIR‐controlled activation of cuproptosis offers great potential as a safe, targeted, and image‐guided antitumor therapy for HNSCC.

Advancements in imaging of head and neck squamous cell carcinoma: A comprehensive review.

As a prevalent malignancy with substantial incidence and mortality worldwide, head and neck squamous cell carcinoma (HNSCC) originates from multiple locations of different tissues, which level up the difficulty and complexity of the cancer detection. The diagnosis requires highresolution imaging modalities and several approaches have been developed within recent decades to provide detailed anatomical information for HNSCC.

Cuproptosis-related lncRNA JPX regulates malignant cell behavior and epithelial-immune interaction in head and neck squamous cell carcinoma via miR-193b-3p/PLAU axis

The development, progression, and curative efficacy of head and neck squamous cell carcinoma (HNSCC) are influenced by complex interactions between epithelial and immune cells. Nevertheless, the specific changes in the nature of these interactions and their underlying molecular mechanisms in HNSCC are not yet fully understood. Cuproptosis, a form of programmed cell death that is dependent on copper, has been implicated in cancer pathogenesis. However, the understanding of cuproptosis in the context of HNSCC remains limited. In this study, we have discovered that cuproptosis-related long non-coding RNAs (CRLs) known as JPX play a role in promoting the expression of the oncogene urokinase-type plasminogen activator (PLAU) by competitively binding to miR-193b-3p in HNSCC. The increased activity of the JPX/miR-193b-3p/PLAU axis in malignant epithelial cells leads to enhanced cell proliferation, migration, and invasion in HNSCC. Moreover, the overexpression of PLAU in tumor epithelial cells facilitates its interaction with the receptor PLAUR, predominantly expressed on macrophages, thereby influencing the abnormal epithelial–immune interactome in HNSCC. Notably, the JPX inhibitor Axitinib and the PLAU inhibitor Palbociclib may not only exert their effects on the JPX/miR-193b-3p/PLAU axis that impacts the malignant tumor behaviors and the epithelial–immune cell interactions but also exhibit synergistic effects in terms of suppressing tumor cell growth and arresting cell cycle by targeting epidermal growth factor receptor (EGFR) and cyclin-dependent kinase (CDK4/6) for the treatment of HNSCC.

Evaluation of a Novel MET-Targeting Camelid-Derived Antibody in Head and Neck Cancer.

In head and neck squamous cell carcinoma (HNSCC), the mesenchymal epithelial transition (MET) receptor drives cancer growth, proliferation, and metastasis. MET is known to be overexpressed in HNSCC and, therefore, is an appealing therapeutic target. In this study, we evaluated MET expression in patients with HNSCC and investigated the potential imaging application of a novel MET-binding single-domain camelid antibody using positron emission tomography/computed tomography (PET/CT) in a preclinical MET-expressing HNSCC model. Multiplex immunostaining for MET protein performed on a tissue microarray from 203 patients with HNSCC found 86% of patients to have MET expression, with 14% having high expression and 53% having low MET expression. Using The Cancer Genome Atlas (TCGA) database, high MET RNA expression was associated with worse progression-free survival and overall survival in patients with HPV-negative HSNCC. Utilizing flow cytometry and immunofluorescence, our novel camelid antibody fused to a human IgG Fc chain (1E7-Fc) showed high binding affinity and specificity to high MET-expressing Detroit 562 cells but not to low MET-expressing HNSCC cells. The efficacy and biodistribution of [89Zr]Zr-1E7-Fc as a PET imaging agent was then investigated in a MET-expressing head and neck xenograft model. [89Zr]Zr-1E7-Fc rapidly localized and showed high tumor uptake in Detroit 562 xenografts (8.4% ID/g at 72 h postinjection), with rapid clearance from the circulatory system (2.7 tumor-to-blood radioactivity ratio at 72 h postinjection). Our preclinical data suggest that the camelid antibody 1E7-Fc could be a potential theranostic agent for HNSCC. Further investigations are warranted to confirm these findings in patients and to evaluate 1E7-Fc as an imaging agent and platform to deliver radionuclide or drug therapy to MET-driven cancers.