Head And Neck Squamous Cell Carcinoma Therapy Research Articles

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.

Gingerol acts as a potent radiosensitizer in head and neck squamous cell carcinoma

Treatment options for advanced head and neck squamous cell carcinoma (HNSCC) are limited and often cause severe toxicity and debilitating long-term impacts. Developing effective and safer treatments is warranted. Several plant extracts have shown their effectiveness, but a comprehensive comparison between plant extracts in HNSCC has not been reported. Our aim was to investigate the effect of different plant extracts on the proliferation and viability of HNSCC cell lines. In addition, we investigated the efficacy of combining cytotoxic plant extracts with radiation. Since RT is a cornerstone in the treatment and management of HNSCC, it is desirable to enhance its efficacy through combination with cytotoxic agents that have minimal side effects. HNSCC cell lines were treated with various plant extracts at different concentrations. MTT assays were performed to identify the most potent anti-tumor plant extract. Colony-formation assays were performed to determine the radiosensitization effect. To investigate the effect on migration, transwell migration assays were performed. Annexin V staining was performed to analyze cell apoptosis. 6-gingerol resulted in the most significant dose-dependent inhibition in all cell lines compared to other plant extracts. Colony-formation assays showed a significant radiosensitizing effect when 6-gingerol was combined with radiation. In addition, the combination of 6-gingerol with radiation resulted in a significant decrease in HNSCC cell migration. Mechanistically, Annexin V staining showed that the combination of 6-gingerol and RT induces a synergistic apoptotic effect in MOC1, MOC2 and SCC9 cells compared to RT alone. In conclusion, 6-gingerol enhances the effect of radiation in HNSCC cell lines and could be a suitable candidate for combination therapy in 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.

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 role of cGAS-STING signaling in the development and therapy of head and neck squamous cell carcinoma.

The cGAS-STING signaling pathway plays a critical role in innate immunity and defense against viral infections by orchestrating intracellular and adaptive immune responses to DNA. In the context of head and neck squamous cell carcinoma (HNSCC), this pathway has garnered significant attention due to its potential relevance in disease development and progression. HNSCC is strongly associated with risk factors such as smoking, heavy alcohol consumption, and human papillomavirus (HPV) infection. The presence or absence of HPV in HNSCC patients has been shown to have a profound impact on patient survival and prognosis, possibly due to the distinct biological characteristics of HPV-associated tumors. This review aims to provide a comprehensive overview of the current therapeutic approaches and challenges in HNSCC management, as well as the involvement of cGAS-STING signaling and its potential in the therapy of HNSCC. In addition, by advancing the present understanding of the mechanisms underlying this pathway, Activation of cGAS-STING-dependent inflammatory signaling downstream of chromosomal instability can exert both anti-tumoral and pro-tumoral effects in a cell-intrinsic manner, suggesting individualized therapy is of great importance. However, further exploration of the cGAS-STING signaling pathway is imperative for the effective management of HNSCC.

Integrated analysis of methylation and transcriptome identifies a novel risk model for diagnosis, prognosis, and immune characteristics in head and neck squamous cell carcinoma.

DNA methylation is an important epigenetic modification that plays a crucial role in the development and progression of various tumors. However, the association between methylation‑driven genes and diagnosis, prognosis, and immune characteristics of head and neck squamous cell carcinoma (HNSCC) remains unclear. We obtained transcriptome, methylation, and clinical data from HNSCC patients in TCGA database, and used MethylMix algorithm to identify methylation-driven genes. A methylation driven gene-related risk model was constructed using Lasso regression analysis, and validated using data from GEO database. Immune infiltration and immune function analysis of the expression profiles were conducted using ssGSEA. Differences in immune checkpoint-related genes were analyzed, and the efficacy of immunotherapy was evaluated using TCIA database. Finally, a series of cell functional experiments were conducted to validate the results. Five methylation-driven genes were identified and utilized to construct a prognostic risk model. Based on the median risk score, all patients were categorized into high-risk and low-risk groups. The K-M analysis revealed that patients in the high-risk group have a worse prognosis. Additionally, the risk model demonstrated better prognostic predictive value as indicated by ROC analysis. GSEA enrichment analysis indicated that gene sets in the high and low-risk groups were primarily enriched in pathways associated with tumor immunity and metabolism. Our subsequent investigations showed that high-risk patients exhibited more immunosuppressive phenotypes, while low-risk patients were more likely to respond positively to immunotherapy. These findings of our research have the potential to improve patient stratification, guide treatment decisions, and advance the development of personalized therapies for HNSCC.

A novel CAF-cancer cell crosstalk-related gene prognostic index based on machine learning: prognostic significance and prediction of therapeutic response in head and neck squamous cell carcinoma

BackgroundCancer-associated fibroblast (CAF)-cancer cell crosstalk (CCCT) plays an important role in tumor microenvironment shaping and immunotherapy response. Current prognostic indexes are insufficient to accurately assess immunotherapy response in patients with head and neck squamous cell carcinoma (HNSCC). This study aimed to develop a CCCT-related gene prognostic index (CCRGPI) for assessing the prognosis and response to immune checkpoint inhibitor (ICI) therapy of HNSCC patients.MethodsTwo cellular models, the fibroblast-cancer cell indirect coculture (FCICC) model, and the fibroblast-cancer cell organoid (FC-organoid) model, were constructed to visualize the crosstalk between fibroblasts and cancer cells. Based on a HNSCC scRNA-seq dataset, the R package CellChat was used to perform cell communication analysis to identify gene pairs involved in CCCT. Least absolute shrinkage and selection operator (LASSO) regression was then applied to further refine the selection of these gene pairs. The selected gene pairs were subsequently subjected to stepwise regression to develop CCRGPI. We further performed a comprehensive analysis to determine the molecular and immune characteristics, and prognosis associated with ICI therapy in different CCRGPI subgroups. Finally, the connectivity map (CMap) analysis and molecular docking were used to screen potential therapeutic drugs.ResultsFCICC and FC-organoid models showed that cancer cells promoted the activation of fibroblasts into CAFs, that CAFs enhanced the invasion of cancer cells, and that CCCT was somewhat heterogeneous. The CCRGPI was developed based on 4 gene pairs: IGF1-IGF1R, LGALS9-CD44, SEMA5A-PLXNA1, and TNXB-SDC1. Furthermore, a high CCRGPI score was identified as an adverse prognostic factor for overall survival (OS). Additionally, a high CCRGPI was positively correlated with the activation of the P53 pathway, a high TP53 mutation rate, and decreased benefit from ICI therapy but was inversely associated with the abundance of various immune cells, such as CD4+ T cells, CD8+ T cells, and B cells. Moreover, Ganetespib was identified as a potential drug for HNSCC combination therapy.ConclusionsThe CCRGPI is reliable for predicting the prognosis and immunotherapy response of HSNCC patients and may be useful for guiding the individualized treatment of HNSCC patients.

CD47-SIRPα Blockade Sensitizes Head and Neck Squamous Cell Carcinoma to Cetuximab by Enhancing Macrophage Adhesion to Cancer Cells.

Developing effective treatments for patients with head and neck squamous cell carcinoma (HNSCC) is a significant challenge. Cetuximab, a first-line targeted therapy for HNSCC, exhibits limited efficacy. Here, we used pooled CRISPR screening to find targets that can synergize with cetuximab and identified CD47 as the leading candidate. Rather than inhibiting cancer cell proliferation, CD47 inhibition promoted cetuximab-triggered antibody-dependent cellular phagocytosis (ADCP), thereby enhancing macrophage-mediated cancer cell removal. The combination of CD47-signal-regulatory protein α (SIRPα) blockade and cetuximab demonstrated strong anticancer activity in vivo. In addition to blocking the phagocytosis checkpoint, CD47-SIRPα inhibition upregulated CD11b/CD18 on the surface of macrophages, which accelerated intercellular adhesion between macrophages and cancer cells to enhance subsequent phagocytosis. Inhibition of the interaction between macrophage CD11b/CD18 and cancer cell intercellular adhesion molecule-1 (ICAM1) eliminated the intercellular adhesion and phagocytosis induced by CD47-SIRPα blockade. Thus, CD47-SIRPα blockade enhances ADCP through CD11b/CD18-ICAM1-mediated intercellular adhesion and sensitizes HNSCC to cetuximab. Significance: CD47-SIRPα blockade increases surface CD11b/CD18 on macrophages to enhance adhesion to cancer cells, resulting in robust synergistic phagocytosis in combination with cetuximab treatment in head and neck squamous cell carcinoma.

Anti-PD-(L)1-Based Neoadjuvant Therapy in Head and Neck Carcinoma: a Meta-analysis of Prospective Clinical Trials.

This meta-analysis aims to evaluate the efficacy and safety of antiprogressive disease (PD)-(L)1-based neoadjuvant therapy in head and neck squamous cell carcinoma (HNSCC) patients and identify potential prognostic biomarkers. Databases were systematically searched for prospective clinical trials evaluating the efficacy and safety of anti-PD-(L)1-based neoadjuvant therapy for HNSCC before January 12, 2024. We estimated the efficacy and safety of neoadjuvant immune checkpoint inhibitors. Subgroup and sensitivity analyses were further performed. A total of 570 patients from 20 studies were included. The pooled major pathological response (MPR), pathological complete response (pCR), and partial pathological response (PPR) rates were 30.7%, 15.3%, and 68.2%, respectively. Surgical complications, surgical delayed rate, all grade treatment-related adverse effects (TRAEs) and ≥Grade 3 TRAEs were 0.6%, 0.3%, 82.6%, and 9.7%, respectively. Best MPR or pCR rate was detected in patients receiving neoadjuvant anti-PD-(L)1 therapy + radiotherapy (with MPR rate of 75.5% and pCR rate of 51.1%) and neoadjuvant anti-PD-(L)1 therapy + chemotherapy groups (with MPR rate of 57.5% and pCR rate of 26.7%). No differences were detected in subgroups stratified by neoadjuvant treatment cycles, human papillomavirus (HPV) status, and tumor location. Patients with baseline Combined Positive Score (CPS) ≥ 20 have higher MPR and pCR rates compared to patients with CPS < 20. High Tumor Cell Proportion Score was also associated with MPR and pCR. Objective response rate is a strong predictor of MPR (odds ratio [OR] = 7.78, 95% confidence interval [CI] = 3.20%-18.91%) and pCR (OR = 3.24, 95% CI = 1.40%-7.48%). Anti-PD-(L)1-based neoadjuvant therapy was effective and safe for HNSCC patients.

Phase 3 randomized study for evaluation of physician choice Rx versus best supportive care as second-line or beyond therapy in head and neck cancer with poor performance status.

LBA6019 Background: Relapsed-recurrent head and neck squamous cell carcinoma (HNSCC) cancers have limited treatment options in the second line and beyond setting. Many of these patients have poor performance status (PS) and are subject to best supportive care (BSC). There is a lack of any level 1 evidence about the benefit of systemic therapy in HNSCC with poor PS. Methods: This was a randomized phase 3 superiority open-label multicentric study. Adult patients (age&gt;=18 years) with relapsed-recurrent HNSCC, qualified to receive 2nd line or beyond systemic palliative therapy and had ECOG PS 2-3 were eligible. Such patients underwent central stratified random assignment 2:1 to either physician choice therapy either triple metronomic chemotherapy (tablet erlotinib 150 mg [fixed-dose] OD, capsule celecoxib 200 mg [fixed-dose] BD, and oral weekly methotrexate 9 mg/m2 orally or intravenous docetaxel [75 mg/m2 3 weekly]) or BSC. The chemotherapy was continued either till the progression of the disease or till the development of intolerable side effects. The primary endpoint was 6 month-overall survival (OS). The OS in the 2 arms was estimated using the Kaplan-Meier method and by log-rank test. A p-value of 0.05 was considered significant. Sample size: The 6-month OS assumed based on our previous data was 20%, we had assumed that it would increase to 50% in the intervention arm with a type 1 error of 5%, type 2 error of 20%, 2:1 allocation (1- BSC and 2- intervention) and 10% lost to follow up rate. The sample size required was 66. The events required for analysis were 47. Results: The study recruited 66 patients between 1st September 2022 to 27th December 2022 with 44 patients in physician choice therapy (PCT) and 22 in the BSC arm. The data was censored for analysis on 1st March 2024. The median age was 50 years (Range 25-75) with a predominantly male population (n=53;85%). The ECOG PS was PS 2 in 56 (84.8%) and PS 3 in 10 (15.2%) patients. The predominant site of primary was the oral cavity with 52 patients (78.8%). The previous number of systemic lines of therapy received were 1 in 41 (62.1%), 2 in 22 (33.3%), and &gt;2 in 3 (4.5%) patients. Except for 2, all patients had a platinum refractory status (64;97%). The PCT was triple metronomic chemotherapy in 41 patients (93.2%; n=44) and docetaxel in 3 patients (6.8%; n=44). The 6-month OS was 9.09% (95% CI 1.56-25.1) in the BSC versus 53.8% (95% CI 37.9-67.2) in the PCT arm (P&lt;0.0001). The median overall survival in PCT was 223.0 days (95% CI 129-283) versus 77.5 days (95%CI 58 -110) in the BSC arm. The corresponding hazard ratio was 0.333 (95%CI 0.187-0.593; P&lt;0.0001). The data regarding adverse events will be presented at the conference. Conclusions: In this first-ever randomized study on poor PS HNSCC patients, warranting second-line and beyond therapy, the administration of systemic therapy led to a substantial improvement in OS. Clinical trial information: CTRI/2022/08/044733 .

Personalized ctDNA for Monitoring Disease Status in Head and Neck Squamous Cell Carcinoma.

Many patients with locoregionally advanced human papillomavirus-negative head and neck squamous cell carcinoma (HNSCC) relapse. ctDNA has the potential to identify minimal residual disease, but its clinical utility for virus-negative HNSCC is not well understood. We retrospectively evaluated a personalized, commercial ctDNA assay (Signatera, Natera) during clinical care of patients treated for predominantly newly diagnosed human papillomavirus-negative HNSCC. Signatera utilizes 16-plex PCR from matched tumor and blood. Objectives were to understand ctDNA detectability and correlate changes posttreatment with disease outcomes. Testing was successful in 100/116 (86%) patients (median age: 65 years, 68% male, 65% smokers); testing failed in 16 (14%) because of insufficient tissue. Oral cavity (55, 47%) tumors were most common; most had stage III to IV disease (82, 71%), whereas 17 (15%) had distant metastases. Pretreatment, 75/100 patients with successful testing (75%) had detectable ctDNA (range: 0.03-4049.69 mean tumor molecules/mL). No clinical features predicted ctDNA detectability or levels (multivariate analysis). At a median follow-up of 5.1 months (range: 0.2-15.1), 55 (55%) had >1 test result (range: 1-7; 194 samples). Of 55 patients, 17 (31%) remained ctDNA positive after starting treatment. Progression-free survival was significantly worse for patients who were ctDNA positive versus ctDNA negative posttreatment (HR, 7.33; 95% confidence interval, 3.12-17.2; P < 0.001); 1-year overall survival was 89.1% versus 100%, respectively (HR, 7.46; 95% confidence interval, 0.46-119.5; P = 0.155). Tumor-informed ctDNA testing is feasible in nonviral HNSCC. ctDNA positivity is an indicator of disease progression and associated with inferior survival. Further research is warranted to understand whether ctDNA may be leveraged to guide therapy in HNSCC.

Predictive capacity of immune-related adverse events and cytokine profiling in neoadjuvant immune checkpoint inhibitor trials for head and neck squamous cell carcinoma.

Certain low-level immune-related adverse events (irAEs) have been associated with survival benefits in patients with various solid tumors on immune checkpoint inhibitors (ICIs). We aimed to investigate the association between irAEs and response to neoadjuvant ICIs in patients with head and neck squamous cell carcinoma (HNSCC) and to identify differences in circulating cytokine levels based on irAE status. This was a retrospective cohort study including three neoadjuvant clinical trials from July 2017 to January 2022: NCT03238365 (nivolumab ± tadalafil), NCT03854032 (nivolumab ± BMS986205), NCT03618654 (durvalumab ± metformin). The presence and type of irAEs, pathologic treatment response, and survival were compared. Canonical linear discriminant analysis (LDA) was performed to identify combinations of circulating cytokines predictive of irAEs using plasma sample multiplex assay. Of 113 participants meeting inclusion criteria, 32 (28.3%) developed irAEs during treatment or follow-up. Positive p16 status was associated with irAEs (odds ratio [OR] 2.489; 95% CI 1.069-6.119; p = 0.043). irAEs were associated with pathologic treatment response (OR 3.73; 95% CI 1.34-10.35; p = 0.011) and with higher OS in the combined cohort (HR 0.319; 95% CI 0.113-0.906; p = 0.032). Patients with irAEs within the nivolumab cohort had significant elevations of select cytokines pre-treatment. Canonical LDA identified key drivers of irAEs among all trials, which were highly predictive of future irAE status. irAEs are associated with response to neoadjuvant ICI therapy in HNSCC and can serve as clinical indicators for improved clinical outcomes. irAEs can be predicted by concentrations of several circulating cytokines prior to treatment.

Neoadjuvant tislelizumab with afatinib for locally advanced head and neck squamous cell carcinoma (neoCHANCE-1): An open-label, single-arm, phase 2 study.

6073 Background: For patients with locally advanced head and neck squamous cell carcinoma (HNSCC), even receiving surgery with adjuvant radiotherapy or chemoradiotherapy, those remain at high risk of recurrence or metastasis. Neoadjuvant immunotherapy has been used in HNSCC, but provides only modest pathological response. Given single agent activity and unique mechanism of action of immune checkpoint inhibitors and epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs), we aimed to evaluate the antitumour activity and safety of neoadjuvant PD-1 blockade with EGFR inhibition in locally advanced HNSCC. Methods: This open-label, single-arm, phase 2 trial was done at a a tertiary hospital in China. Eligible patients were aged 18 years or older and had resectable HNSCC disease, had an Eastern Cooperative Oncology Group performance status of 0–1, had at least one measurable target lesion according to the RECIST 1.1, had no prior antitumor therapy for HNSCC. Patients received neoadjuvant treatment with intravenous tislelizumab (200 mg) on the first day of each 3 week, with totally two cycles and orally afatinib (30 mg) starting on the first treatment day and ending on the day before surgery, with totally six weeks, and then patients proceeded to receive surgical resection. The primary endpoint was major pathological response, defined as the presence of 10% or less residual viable tumour at the time of surgery. Results: A total of 25 patients were enrolled completed the neoadjuvant therapy. Eight of 23 evaluable patients exhibited a major pathological response (MPR) (35%; 95% confidence interval [CI], 16%—57%), of which four had a complete pathological response of primary tumor (17%, 95%CI, 5%—39%). The overall response rate was 48% (12/25, 95%CI: 28%—69%) and disease control rate was 100% (25/25, 95%CI: 86%—100%). Common grade 3—4 adverse events included diarrhea (5/25 [20%]), hypokalemia (4/25 [16%]) and rash (3/25 [12%]). No treatment related fatalities were observed. Immunologically, post-neoadjuvant treatment demonstrated increased CD3, CD8, and CD56 expression within the tumor microenvironment. The increase of CD8 and CD56 expression level was significant higher in patients achieving MPR, along with elevated circulatory NK cells at baseline, compared to those in patients achieving non-MPR. Conclusions: This study underscores encouraging antitumor activity, manageable toxicity profile and promising immune activation elicited by neoadjuvant tislelizumab plus afatinib for HNSCC, which deserves further assessment. Clinical trial information: NCT05517330 .

Effective Radiosensitization of HNSCC Cell Lines by DNA-PKcs Inhibitor AZD7648 and PARP Inhibitors Talazoparib and Niraparib.

(1) Head and neck squamous cell carcinoma (HNSCC) is common, while treatment is difficult, and mortality is high. Kinase inhibitors are promising to enhance the effects of radiotherapy. We compared the effects of the PARP inhibitors talazoparib and niraparib and that of the DNA-PKcs inhibitor AZD7648, combined with ionizing radiation. (2) Seven HNSCC cell lines, including Cal33, CLS-354, Detroit 562, HSC4, RPMI2650 (HPV-negative), UD-SCC-2 and UM-SCC-47 (HPV-positive), and two healthy fibroblast cell lines, SBLF8 and SBLF9, were studied. Flow cytometry was used to analyze apoptosis and necrosis induction (AnnexinV/7AAD) and cell cycle distribution (Hoechst). Cell inactivation was studied by the colony-forming assay. (3) AZD7648 had the strongest effects, radiosensitizing all HNSCC cell lines, almost always in a supra-additive manner. Talazoparib and niraparib were effective in both HPV-positive cell lines but only consistently in one and two HPV-negative cell lines, respectively. Healthy fibroblasts were not affected by any combined treatment in apoptosis and necrosis induction or G2/M-phase arrest. AZD7648 alone was not toxic to healthy fibroblasts, while the combination with ionizing radiation reduced clonogenicity. (4) In conclusion, talazoparib, niraparib and, most potently, AZD7648 could improve radiation therapy in HNSCC. Healthy fibroblasts tolerated AZD7648 alone extremely well, but irradiation-induced effects might occur. Our results justify in vivo studies.

The use of pembrolizumab monotherapy for the management of head and neck squamous cell carcinoma (HNSCC) in the UK.

Pembrolizumab has received approval in the UK as first-line monotherapy for recurrent and/or metastatic HNSCC (R/M HNSCC) following the results of the KEYNOTE-048 trial, which demonstrated a longer overall survival (OS) in comparison to the EXTREME chemotherapy regimen in patients with a combined positive score (CPS) ≥1. In this article, we provide retrospective real-world data on the role of pembrolizumab monotherapy as first-line systemic therapy for HNSCC across 18 centers in the UK from March 20, 2020 to May 31, 2021. 211 patients were included, and in the efficacy analysis, the objective response rate (ORR) was 24.7%, the median progression-free survival (PFS) was 4.8 months (95% confidence interval [CI]: 3.6-6.1), and the median OS was 10.8 months (95% CI 9.0-12.5). Pembrolizumab monotherapy was well tolerated, with 18 patients having to stop treatment owing to immune-related adverse events (irAEs). 53 patients proceeded to second-line treatment with a median PFS2 of 10.2 months (95% CI: 8.8-11.5). Moreover, patients with documented irAEs had a statistically significant longer median PFS (11.3 vs. 3.3 months; log-rank p value = <.001) and median OS (18.8 vs. 8.9 months; log-rank p value <.001). The efficacy and safety of pembrolizumab first-line monotherapy for HNSCC has been validated using real-world data.

Targeting BRD4: Potential therapeutic strategy for head and neck squamous cell carcinoma (Review).

As a member of BET (bromodomain and extra-terminal) protein family, BRD4 (bromodomain‑containing protein 4) is a chromatin‑associated protein that interacts with acetylated histones and actively recruits regulatory proteins, leading to the modulation of gene expression and chromatin remodeling. The cellular and epigenetic functions of BRD4 implicate normal development, fibrosis and inflammation. BRD4 has been suggested as a potential therapeutic target as it is often overexpressed and plays a critical role in regulating gene expression programs that drive tumor cell proliferation, survival, migration and drug resistance. To address the roles of BRD4 in cancer, several drugs that specifically target BRD4 have been developed. Inhibition of BRD4 has shown promising results in preclinical models, with several BRD4 inhibitors undergoing clinical trials for the treatment of various cancers. Head and neck squamous cell carcinoma (HNSCC), a heterogeneous group of cancers, remains a health challenge with a high incidence rate and poor prognosis. Conventional therapies for HNSCC often cause adverse effects to the patients. Targeting BRD4, therefore, represents a promising strategy to sensitize HNSCC to chemo‑ and radiotherapy allowing de‑intensification of the current therapeutic regime and subsequent reduced side effects. However, further studies are required to fully understand the underlying mechanisms of action of BRD4 in HNSCC in order to determine the optimal dosing and administration of BRD4‑targeted drugs for the treatment of patients with HNSCC.

Study of head and neck squamous cell carcinoma transcriptome after proton therapy

Aim. To evaluate changes in the transcriptome of head and neck squamous cell carcinoma (HNSCC) tissue cells in patients after proton therapy.Materials and methods. Biopsy material obtained from 3 HNSCC patients before and after proton therapy at a total dose of 10 isoGy was homogenized, purified, and concentrated. Then total RNA was isolated with further purification and concentration with the RNA Clean &amp; Concentrator kit (Zymo Research). Library quantitation was assessed using the Qubit 2.0 instrument (Invitrogen, Life Technologies). After isolation of 1 μg total RNA for sequencing, libraries were prepared on the Illumina platform using the TruSeq RNA Sample Prep Kit v2 with a 10-cycle enrichment step according to the manufacturer’s recommendations. The quality of RNA and the resulting libraries was checked using the Agilent 2100 Bioanalyzer system (Agilent Tec. Inc., USA). The RIN parameter for RNA was at least 7. The library concentration was assessed by real-time PCR on the CFX96 Touch Real-Time PCR Detection System (Bio-Rad, USA). Final libraries were pooled in equimolar ratios before sequencing on the Illumina HiSeq 2500 platform using 50 base-pair paired-end reads. The Q20 parameter for all samples was &gt; 97%, and the number of reads averaged 60.2 million per sample. Raw reads were processed using the RTA 1.17.21.3 and Casava 1.8.2 (Illumina). The enrichment analysis was performed using the PANTHER 17.0 software.Results. The transcriptome analysis of HNSCC after proton radiation therapy (5 x 2 isoGy) at a total dose of 10 isoGy revealed 1,414 significantly differentially expressed genes. The 10 most and least expressed genes and their associated signaling pathways were identified. A number of signaling pathways associated with the underexpressed genes were detected in HNSCC after proton therapy, such as: STAT5; PD-1 signaling pathway; marked MET-mediated activation of PTK2 signaling pathway, PDGF signaling; CD22-mediated regulation of BCR; and FCERI-mediated MAPK activation. In addition to the above signaling pathways, activation of collagen degradation, FCGR3A-mediated phagocytosis, and FCGR3A-mediated interleukin (IL)-10 synthesis are of interest. In the enrichment analysis among highly expressed genes, keratinization and biological oxidation processes were activated in HNSCC tissues after proton therapy.Conclusion. Proton therapy in HNSCC leads to overexpression of genes involved in the regulation of keratinization and biological oxidation processes as well as to underexpression of genes associated with suppression of signaling pathways: STAT5, PD-1, MET-mediated activation of PTK2 signaling pathway, PDGF signaling; CD22-mediated regulation of BCR; FCERI-mediated MAPK activation, collagen degradation, FCGR3A-mediated phagocytosis activation, and FCGR3A-mediated IL-10 synthesis. All signaling pathways of underexpressed genes function in HNSCC cells if there is no negative influence on the tumor from outside (irradiation or delivery of antitumor drugs). The predominance of suppressed signaling pathways over activated ones most likely indicates a decrease in the functional potential of cells after proton therapy. The dose-dependence of PT effects necessitates further study of changes in cellular and molecular-genetic signatures of HNSCC after proton irradiation with different doses.

Abstract CT226: Phase 2 study of oral CCR4 antagonist FLX475 (tivumecirnon) plus pembrolizumab in subjects with head and neck squamous cell carcinoma (HNSCC) previously treated with checkpoint inhibitor

Abstract BACKGROUND: FLX475 (tivumecirnon) is a selective CCR4 antagonist designed to block the recruitment of immunosuppressive regulatory T cells (Treg) into the tumor microenvironment. The FLX475-02 trial (NCT03674567) is a phase 1/2 study of FLX475 as monotherapy and in combination with pembrolizumab in subjects with advanced cancer. Early encouraging data on the biologic effects, safety and antitumor activity of FLX475 have previously been presented. We now present the results from the Phase 2 cohort of combination therapy in subjects with head and neck squamous cell carcinoma (HNSCC) previously treated with checkpoint inhibitor (CPI-experienced). METHODS: Subjects with CPI-experienced, recurrent or metastatic (R/M) HNSCC received FLX475 100 mg orally once daily with pembrolizumab (200 mg IV Q3 weeks). The primary study objectives were safety and tolerability, and antitumor activity. The primary efficacy endpoint was objective response rate (ORR), based on RECIST 1.1 criteria. Additional efficacy endpoints included progression-free survival (PFS). Safety was evaluated as per CTCAE v4.03. Data cutoff was 11DEC2023. RESULTS: For the 32 subjects with HNSCC evaluable for response, median follow-up was 14.8 months (range 2.2-40.1) and median lines of prior therapy were 3 (1-6). Median age of subjects was 59 yrs; 94% were male and 75% were Caucasian. Primary tumor location was oropharynx in 56%. As previously reported, the only adverse event clearly determined to be treatment related to FLX475 to date has been asymptomatic and reversible QT prolongation (managed by dose reduction). Among the subjects evaluable for response regardless of HPV or PD-L1 status (n=32), confirmed partial response (cPR) was observed in 5 subjects (ORR: 15.6%, 95% CI 6-32%). Among the subgroup of subjects whose tumors were HPV positive (n=18), 8 (44%) experienced reduction from baseline in target lesion measurements and cPR was observed in 4 (ORR: 22.2%, 95% CI 9-46%). Among the subgroup of subjects whose tumors expressed PD-L1 (combined positive score [CPS] ≥1%) (n=22), cPR was observed in 4 (ORR: 18.2%, 95% CI 7-39%). At data cutoff, the HPV-positive subgroup median PFS was 2.9 months (95% CI 2-10.3) and 3 subjects were still on treatment. CONCLUSIONS: FLX475, an oral CCR4 antagonist, has previously demonstrated clear monotherapy activity in EBV+ extranodal NK/T-cell lymphoma and promising combination activity with pembrolizumab in EBV+ gastric cancer and CPI-naïve non-small cell lung cancer. In this completed Phase 2 cohort of subjects with CPI-experienced R/M HNSCC, FLX475 in combination with pembrolizumab was shown to be well tolerated and has demonstrated encouraging clinical activity particularly in those with HPV-positive tumors, supporting the continued development of this combination therapy for CPI-experienced HNSCC. Citation Format: Jameel Muzaffar, Kedar Kirtane, Rebecca Redman, Muh-Hwa Yang, Tae Min Kim, Stephen Liu, Ryan Lynch, Julie Brahmer, Patricia LoRusso, Brian Henick, Sung-bae Kim, Yin-Hsun Feng, Michael Chisamore, Paul Kassner, Dirk Brockstedt, Nicole Nasrah, Rakesh Goyal, William Y. Ho, Victoria Villaflor. Phase 2 study of oral CCR4 antagonist FLX475 (tivumecirnon) plus pembrolizumab in subjects with head and neck squamous cell carcinoma (HNSCC) previously treated with checkpoint inhibitor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT226.

Abstract 6646: Investigating the combination of radiation and subsequent immune checkpoint inhibitor treatment in head and neck squamous cell carcinoma models

Abstract Purpose: Head and neck squamous cell carcinoma (HNSCC) is often marked by an immunosuppressive tumor microenvironment, which contributes to the dismal 10-20% response rate to immune checkpoint inhibitor (ICI) therapy in HNSCC patients. Radiotherapy (RT) is a currently standard of care and frontline therapy for HNSCC, yet resistance is common. We sought to examine the combination therapy of RT followed by ICI therapy to test if RT induces an in situ vaccination which enhances the efficacy of subsequent ICI. Methods: We utilized SCC cell lines derived from K15.KrasG12D/Smad4−/− SCCs, which mimic the progression of HPV-unrelated HNSCC, and transplanted SCC cells into immune-competent C57BL/6J mouse recipients. Mice were subjected to RT followed by anti-PD-L1/anti-TGFb therapy. CD8+ splenic T cells of responder or non-responder mice were examined by paired single-cell VDJ sequencing and single cell RNA sequencing (TCR/sc-RNAseq) to look for adaptations of the cytotoxic T cell compartment following combination therapy. Responder and non-responder tumor lines or tumors were treated with RT alone in vitro and in vivo, respectively, to examine major histocompatibility complex I (MHC-I) levels on tumor cells. Results: Responders to this combination therapy exhibited complete tumor eradication while non-responders displayed rapid tumor progression. When re-challenged with same HNSCCs cells, responders rejected implanted tumor cells while naïve recipients rapidly developed HNSCCs. Single-cell TCR sequencing of splenic CD8+ T cells revealed that responders, but not naïve recipients exhibited multiclonal CD8+ T cell expansion specifically of memory cell populations. Responder tumor cells exhibited greater levels of MHC-I protein level presentation than non-responders when stimulated with RT. Conclusions: Our data suggest that 1) elevated MHC-I by SCC tumor cells presentation driven by RT and ICI combination therapy facilitate a systemic expansion of memory CD8+ T cell clonotypes which drive anti-tumor immunity and 2) MHC-I expression at baseline or when induced by RT may serve as a predictive marker for therapeutic response to RT and ICI combination therapy in HNSCCs. Citation Format: Hanne Lind, Alexander Strait, Spencer Hall, Jack B. Goon, John D. Aleman, Samantha Chen, Philip Owens, Jing H. Wang, Christian Young, Xiao-Jing Wang. Investigating the combination of radiation and subsequent immune checkpoint inhibitor treatment in head and neck squamous cell carcinoma models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6646.

RNA-binding protein HuR reprograms immune T cells and promotes oral squamous cell carcinoma

Hu Antigen R, also known as ELAVL1 (HuR), is a key posttranscriptional regulator in eukaryotic cells. HuR overexpression promotes several malignancies, including head and neck squamous cell carcinoma (HNSCC). However, its immune dysfunction-associated tumorigenesis pathways remain unknown. We examined HuR's effects on oral malignancies and immune cell function in vitro and in vivo using oral carcinoma cells and transgenic HuR knockout (KO) mice. CRISPR/Cas9-mediated HuR deletion in mice syngeneic oral cancer cells eliminated colony formation and tumor development. HuR-KO tumors had a lower tumor volume, fewer CD4+CD25+FoxP3+ regulatory T cells, and more CD8+ T cells, suggesting that HuR may suppress the immune response during oral cancer progression. In contrast, HuR KO oral epithelial tissues are resistant to 4NQO-induced oral malignancies compared to control tumor-bearing mice. HuR KO mice showed fewer Tregs and greater IFN levels than WT tumor-bearing mice, suggesting anticancer activity. Finally, the HuR inhibitor pyrvinium pamoate lowers tumor burden by enhancing CD8+ infiltration at the expense of CD4+, suggesting anticancer benefits. Thus, HuR-dependent oral neoplasia relies on immunological dysfunction, suggesting that decreasing HuR may boost antitumor potential and offer a novel HNSCC therapy.