Pembrolizumab plus concurrent chemoradiotherapy versus placebo plus concurrent chemoradiotherapy in patients with locally advanced squamous cell carcinoma of the head and neck (KEYNOTE-412): a randomised, double-blind, phase 3 trial.

BACKGROUND: Despite multimodal therapy, 5-year overall survival for locally advanced head and neck squamous cell carcinoma (HNSCC) is about 50%. We assessed the addition of pembrolizumab to concurrent chemoradiotherapy for locally advanced HNSCC. METHODS: In the randomised, double-blind, phase 3 KEYNOTE-412 trial, participants with newly diagnosed, high-risk, unresected locally advanced HNSCC from 130 medical centres globally were randomly assigned (1:1) to pembrolizumab (200 mg) plus chemoradiotherapy or placebo plus chemoradiotherapy. Randomisation was done using an interactive response technology system and was stratified by investigator's choice of radiotherapy regimen, tumour site and p16 status, and disease stage, with participants randomly assigned in blocks of four per stratum. Participants, investigators, and sponsor personnel were masked to treatment assignments. Local pharmacists were aware of assignments to support treatment preparation. Pembrolizumab and placebo were administered intravenously once every 3 weeks for up to 17 doses (one before chemoradiotherapy, two during chemoradiotherapy, 14 as maintenance therapy). Chemoradiotherapy included cisplatin (100 mg/m2) administered intravenously once every 3 weeks for two or three doses and accelerated or standard fractionation radiotherapy (70 Gy delivered in 35 fractions). The primary endpoint was event-free survival analysed in all randomly assigned participants. Safety was analysed in all participants who received at least one dose of study treatment. This study is registered with ClinicalTrials.gov, NCT03040999, and is active but not recruiting. FINDINGS: Between April 19, 2017, and May 2, 2019, 804 participants were randomly assigned to the pembrolizumab group (n=402) or the placebo group (n=402). 660 (82%) of 804 participants were male, 144 (18%) were female, and 622 (77%) were White. Median study follow-up was 47·7 months (IQR 42·1-52·3). Median event-free survival was not reached (95% CI 44·7 months-not reached) in the pembrolizumab group and 46·6 months (27·5-not reached) in the placebo group (hazard ratio 0·83 [95% CI 0·68-1·03]; log-rank p=0·043 [significance threshold, p≤0·024]). 367 (92%) of 398 participants treated in the pembrolizumab group and 352 (88%) of 398 participants treated in the placebo group had grade 3 or worse adverse events. The most common grade 3 or worse adverse events were decreased neutrophil count (108 [27%] of 398 participants in the pembrolizumab group vs 100 [25%] of 398 participants in the placebo group), stomatitis (80 [20%] vs 69 [17%]), anaemia (80 [20%] vs 61 [15%]), dysphagia (76 [19%] vs 62 [16%]), and decreased lymphocyte count (76 [19%] vs 81 [20%]). Serious adverse events occurred in 245 (62%) participants in the pembrolizumab group versus 197 (49%) participants in the placebo group, most commonly pneumonia (43 [11%] vs 25 [6%]), acute kidney injury (33 [8%] vs 30 [8%]), and febrile neutropenia (24 [6%] vs seven [2%]). Treatment-related adverse events led to death in four (1%) participants in the pembrolizumab group (one participant each from aspiration pneumonia, end-stage renal disease, pneumonia, and sclerosing cholangitis) and six (2%) participants in the placebo group (three participants from pharyngeal haemorrhage and one participant each from mouth haemorrhage, post-procedural haemorrhage, and sepsis). INTERPRETATION: Pembrolizumab plus chemoradiotherapy did not significantly improve event-free survival compared with chemoradiotherapy alone in a molecularly unselected, locally advanced HNSCC population. No new safety signals were seen. Locally advanced HNSCC remains a challenging disease that requires better treatment approaches. FUNDING: Merck Sharp & Dohme, a subsidiary of Merck & Co, Rahway, NJ, USA.

Barbed suture in neck dissection: a randomized clinical study on efficacy, safety and aesthetic outcome.

PURPOSE: The resection of lymph nodes/neck dissection is a typical part of the surgical treatment of head and neck malignancies. The aim of this study was to compare subcutaneous closure using single knotted, braided suture (VicrylTM, standard arm) with continuous self-locking, monofilament barbed suture (V-LocTM, experimental arm). METHODS: Neck Lock was a randomized clinical trial at a single tertiary referral center. It was conducted from 2016 till 2022 with a follow-up period of 3 months. Assessment of safety and aesthetic outcome was double-blinded. 68 patients were randomized after application of exclusion criteria. Subcutaneous wound closure was performed in an intrapatient randomized fashion for suture technique. The primary endpoint was the duration of subcutaneous sutures. Wound healing and scar formation were recorded at multiple postoperative intervals as secondary endpoints. RESULTS: The median age was 61 years, 89.7% were male. 92.6% suffered from a squamous cell carcinoma. There was a significant difference in median subcutaneous suture time (p = 0.024) between the experimental (6:11 ± 2:30 min) and standard (7:01 ± 2.42 min) arms. There was no significant difference in safety when assessing adverse events (AEs). At least one AE occurred in 14.7% vs. 5.9%, for barbed and smooth sutures respectively (p = 0.16). CONCLUSION: For neck dissection of head and neck malignancies, subcutaneous wound closure with self-locking sutures offers significant time savings over the single knot technique with similar safety and aesthetic results. TRIAL REGISTRATION INFORMATION: The trial was registered with WHO acknowledged primary registry "German Clinical Trials Register" under the ID DRKS00025831 ( https://drks.de/search/de/trial/DRKS00025831 ).

Treatment regimens for laryngeal and hypopharyngeal squamous cell carcinoma: a "real life" multicenter study of 2307 patients.

OBJECTIVE: This retrospective multicenter study aimed to evaluate surgical versus conservative treatment in patients with hypopharyngeal and laryngeal cancer under real world conditions. METHODS: This study included 2307 patients diagnosed with hypopharyngeal or laryngeal squamous cell carcinoma (SCC) in five German tertiary head and neck centers between 01/2004 and 12/2014. Overall, 783 patients with advanced SCC consecutively underwent laryng(opharyng)ectomy (L(P)E). Patient chart data regarding age, sex, tumor location, TNM status, grading, indication for L(P)E, treatment modalities, R status, postoperative complications, and hospitalization time were analyzed. Patients with lacking data and incomplete staging and those who refused treatment or did not comply with the recommended treatment were excluded from survival analysis. RESULTS: A slight but significant increase was observed in L(P)E, referring to an increasing rate of tumor recurrence. While T1/2N0M0 laryngeal and hypopharyngeal cancer patients showed comparable overall survival (OS) for surgical and conservative treatment, surgery showed significantly better OS in lymph node-positive individuals and locally advanced tumor stages. Tumor recurrence occurred in more than one-third of the cases. In particular, in early glottic cancer recurrence, L(P)E represents a curative and safe treatment option, whereas in supraglottic and hypopharyngeal cancer, L(P)E was associated with reduced survival rates. Notably, 36% of patients with supraglottic cancer and 59% of patients with hypopharyngeal cancer recurrence could only be treated with palliative care. CONCLUSION: Comparable survival rates were demonstrated for cT1/2N0M0 laryngeal and hypopharyngeal SCC compared with primary chemo-/radiotherapy and larynx-preserving surgery. Better OS was achieved after surgery in nodal-positive patients and in those with locally advanced disease. Tumor recurrence should be anticipated in up to 39% of cases. Glottic cancer recurrence can be successfully and safely treated with L(P)E, whereas OS is reduced in hypopharyngeal cancer and possibly in supraglottic cancer.

The HLA ligandome of oropharyngeal squamous cell carcinomas reveals shared tumour-exclusive peptides for semi-personalised vaccination.

BACKGROUND: The immune peptidome of OPSCC has not previously been studied. Cancer-antigen specific vaccination may improve clinical outcome and efficacy of immune checkpoint inhibitors such as PD1/PD-L1 antibodies. METHODS: Mapping of the OPSCC HLA ligandome was performed by mass spectrometry (MS) based analysis of naturally presented HLA ligands isolated from tumour tissue samples (n = 40) using immunoaffinity purification. The cohort included 22 HPV-positive (primarily HPV-16) and 18 HPV-negative samples. A benign reference dataset comprised of the HLA ligandomes of benign haematological and tissue datasets was used to identify tumour-associated antigens. RESULTS: MS analysis led to the identification of naturally HLA-presented peptides in OPSCC tumour tissue. In total, 22,769 peptides from 9485 source proteins were detected on HLA class I. For HLA class II, 15,203 peptides from 4634 source proteins were discovered. By comparative profiling against the benign HLA ligandomic datasets, 29 OPSCC-associated HLA class I ligands covering 11 different HLA allotypes and nine HLA class II ligands were selected to create a peptide warehouse. CONCLUSION: Tumour-associated peptides are HLA-presented on the cell surfaces of OPSCCs. The established warehouse of OPSCC-associated peptides can be used for downstream immunogenicity testing and peptide-based immunotherapy in (semi)personalised strategies.

Analysis, identification and visualization of subgroups in genomics.

MOTIVATION: Cancer is a complex and heterogeneous disease involving multiple somatic mutations that accumulate during its progression. In the past years, the wide availability of genomic data from patients' samples opened new perspectives in the analysis of gene mutations and alterations. Hence, visualizing and further identifying genes mutated in massive sets of patients are nowadays a critical task that sheds light on more personalized intervention approaches. RESULTS: Here, we extensively review existing tools for visualization and analysis of alteration data. We compare different approaches to study mutual exclusivity and sample coverage in large-scale omics data. We complement our review with the standalone software AVAtar ('analysis and visualization of alteration data') that integrates diverse aspects known from different tools into a comprehensive platform. AVAtar supplements customizable alteration plots by a multi-objective evolutionary algorithm for subset identification and provides an innovative and user-friendly interface for the evaluation of concurrent solutions. A use case from personalized medicine demonstrates its unique features showing an application on vaccination target selection. AVAILABILITY: AVAtar is available at: https://github.com/sysbio-bioinf/avatar. CONTACT: hans.kestler@uni-ulm.de, phone: +49 (0) 731 500 24 500, fax: +49 (0) 731 500 24 502.

Influence of Bruton's Tyrosine Kinase (BTK) on Epithelial-Mesenchymal Transition (EMT) Processes and Cancer Stem Cell (CSC) Enrichment in Head and Neck Squamous Cell Carcinoma (HNSCC).

Constitutively active kinases play a crucial role in carcinogenesis, and their inhibition is a common target for molecular tumor therapy. We recently discovered the expression of two oncogenic isoforms of Bruton's Tyrosine Kinase (BTK) in head and neck squamous cell carcinoma (HNSCC), Btk-p80 and BTK-p65. However, the precise role of BTK in HNSCC remains unclear. Analyses of a tissue microarray containing benign and malignant as well as inflammatory tissue samples of the head and neck region revealed the preferential expression of BTK-p80 in malignant tissue, whereas BTK-p65 expression was confirmed in over 80% of analyzed metastatic head and neck tumor cases. Therefore, processes associated with metastasis, like cancer stem cell (CSC) enrichment and the epithelial-mesenchymal transition (EMT), which in turn depend on an appropriate cytokine milieu, were analyzed. Treatment of HNSCC-derived cell lines cultured under 3D conditions with the BTK inhibitor AVL-292 caused reduced sphere formation, which was accompanied by reduced numbers of ALDH1A1+ CSCs as well as biological changes associated with the EMT. Moreover, we observed reduced NF-κB expression as well as altered NF-κB dependent pro-tumorigenic and EMT-associated cytokine release of IL-6, IFNγ, and TNFα when BTK activity was dampened. Therefore, an autocrine regulation of the oncogenic BTK-dependent process in HNSCC can be suggested, with BTK inhibition expected to be an effective treatment option for HNSCC.

[Immunotherapy in the context of other head and neck cancer treatment modalities-highlights of the ASCO and ESMO annual meeting 2022]. / Immuntherapie im Kontext anderer Therapiemodalitäten von Kopf-Hals-Tumoren ­ Highlights der ASCO- und ESMO-Jahrestagung 2022.

Immunotherapeutic agents are nowadays established for treatment of a wide variety of tumor entities, including squamous cell carcinoma of the head and neck region. Originally used in the palliative setting, these are increasingly administered with curative intent, e.g., as neoadjuvant treatment. Current research addresses the questions of which patients benefit from the treatment and which combination therapies are successful. The present article summarizes relevant findings of the two international cancer congresses in 2022.

[Patient-reported outcomes in head and neck cancer treatment: relevance, challenges, and benefit]. / Patientenberichtete Endpunkte in der Kopf-Hals-Tumortherapie: Relevanz, Herausforderungen und Nutzen.

Next to overall survival, quality of life is becoming more and more pivotal for cancer patients. The various domains of quality of life are complex and have different value to each patient. However, not only patients but also health care professionals, the pharmaceutical industry, and regulatory bodies ask: How can quality of life be reliably ascertained in clinical trials? For this purpose, carefully developed and validated specific questionnaires are needed: the patient-reported outcome measures (PROMs). A key challenge is to define how results based on PROMs can be used for shared decision-making. Next to clinical factors such as health and nutritional status, quality of life acts as a prognostic factor for overall survival in cancer. Thus, it is crucial to take quality of life into account in daily clinical practice.

Protein-Based Oncopanel as Addition to Target Sequencing in Head and Neck Squamous Cell Carcinoma to Individualize Treatment Decisions.

Head and neck squamous cell carcinoma (HNSCC) is a heterogeneous group of cancers and patients have limited therapy options if primary treatment fails. Therefore, additional information about the biology of the tumor is essential. Here we performed a feasibility study of concurrently applying two precision diagnostic tools in a consecutive series of HNSCC patients. We analyzed tumor samples of 31 patients using a genomic (oncomine) and a proteomic, immunohistochemical approach (oncopanel) and compared the result, also in the focus on their overlapping therapeutical targets. We found no strong correlation between the two approaches and observed a higher proportion of marker expression for the immunohistochemical panel. However, both panels show in our HNSCC cohort distinct patterns with druggable targets. The data suggest that both approaches complement one another and can be applied side-by-side to identify the best targets for the development of individual treatment options for HNSCC patients.

[Immunotherapy of head and neck cancer : Highlights of the ASCO and ESMO annual meetings 2021]. / Immuntherapie von Kopf-Hals-Tumoren : Highlights der ASCO- und ESMO-Jahrestagung 2021.

BACKGROUND: This year's American Society of Clinical Oncology (ASCO) meeting included interesting data on first-line therapy of nasopharyngeal carcinomas with PD­1 inhibitors and on checkpoint inhibition in various clinical constellations. At the European Society of Medical Oncology (ESMO) meeting, the results of the CheckMate-651 study were presented. MATERIALS AND METHODS: All abstracts and presentations from the ASCO and ESMO meetings 2021 on immunotherapy in head and neck cancer (HNSCC) were evaluated for their relevance. The most interesting studies are elaborated upon herein. RESULTS: Studies on locally advanced HNSCC showed an improved response after neoadjuvant pembrolizumab administration. A second cycle did not improve the response rate, but the proportion of patients with a good response was almost doubled. The CheckRad CD8 study showed an improvement in progression-free survival by induction chemoimmunotherapy with tremelimumab and durvalumab followed by stratification according to the CD8 immune cell infiltrate. Two studies were presented on first-line treatment of recurrent/metastatic nasopharyngeal carcinomas. Chemoimmunotherapy showed a higher response rate and prolonged progression-free survival with a similar adverse event profile. In recurrent/metastatic HNSCC, the CheckMate 651 study showed an increased duration of response with nivolumab and ipilimumab and higher response rates than pembrolizumab alone. The primary endpoints for overall survival were not achieved. CONCLUSION: PD­1 inhibition has great potential to change the therapeutic landscape for nasopharyngeal carcinomas in the future. In HNSCC, CD8 tumor infiltrate presents a promising predictive marker for selecting patients who can benefit from radioimmunotherapy. The combination of nivolumab and ipilimumab did not improve overall survival in palliative first-line therapy; thus, no change in the current standard is expected.

[Centralization, Specialization, and Outpatient Care for Head and Neck Tumor Patients]. / Zentralisierung, Spezialisierung und Ambulantisierung der Versorgung von Kopf-Hals-Tumorpatienten.

Demographically, the German population is aging and becoming more morbid. At the same time, urbanization trends, medical overcapacities, and increasing care costs are being observed in association with a tight healthcare budget. Centralization, specialization, and outpatient care are intended to provide a remedy and can be controlled by modifications to remuneration. This upheaval poses new challenges for patients and physicians, which were analyzed exemplarily at the Head and Neck Tumor (HNC) Center of the University Hospital Ulm. This is a retrospective, monocentric cohort study on the development of patient volume, catchment area, treatment modality, and demographics including 2070 HNC patients at the ENT clinic between the years 2011 and 2020. It was observed that the number (new diagnoses 2011: 134 vs. 2020: 204) and the average age (2011: 61.5 years vs. 2020: 65.8 years; p < 0.0001) of HNC patients increased over time. In addition, patients tended to travel longer distances (2011: 54.4 km vs. 2020: 64.4 km; p = 0.05). At the same time, the mean number of consultations and treatments per patient per 5-year follow-up interval grew (at initial diagnosis in 2011: 7.8 vs. 2016: 10.4; p = 0.0003), with the proportion of outpatient contacts increasing from 58.9 % to 62.4 % (p = 0.09) from 2011 to 2020. Accordingly, clinical centers are expected to become more important in the care of HNC patients as the healthcare system becomes more specialized, and centralized with a growing outpatient setting. The following consequences for patient care should be considered in restructuring strategies.

Prospective longitudinal study of immune checkpoint molecule (ICM) expression in immune cell subsets during curative conventional therapy of head and neck squamous cell carcinoma (HNSCC).

Programmed-death-1 (PD1) antibodies are approved for recurrent and metastatic head and neck squamous cell carcinoma. Multiple drugs targeting costimulatory and coinhibitory immune checkpoint molecules (ICM) have been discovered. However, it remains unknown how these ICM are affected by curative conventional therapy on different immune cell subsets during the course of treatment. In the prospective noninterventional clinical study titled "Immune Response Evaluation to Curative conventional Therapy" (NCT03053661), 22 patients were prospectively enrolled. Blood samples were drawn at defined time points throughout curative conventional treatment and follow-up. Immune cells (IC) from the different time points were assessed by multicolor flow cytometry. The following ICM were measured by flow cytometry: PD1, CTLA4, BTLA, CD137, CD27, GITR, OX40, LAG3 and TIM3. Dynamics of ICM expression were assessed using nonparametric paired samples tests. Significant changes were noted for PD1, BTLA and CD27 on multiple IC types during or after radiotherapy. Nonsignificant trends for increased expression of OX40 and GITR from baseline until the end of RT were observed on CD4 T cells and CD4+ CD39+ T cells. In patients with samples at recurrence of disease, a nonsignificant increase of TIM3 and LAG3 positive CD4+ CD39+ T cells was evident, accompanied by an increase of double positive cells for TIM3/LAG3. Potential future targets to be combined with RT in the conventional treatment and anti-PD1/PD-L could be BTLA agonists, or agonistic antibodies to costimulatory ICM like CD137, OX40 or GITR. The combination of cetuximab with CD27 agonistic antibodies enhancing ADCC or the targeting of TIM3/LAG3 may be another promising strategy.

Adenosine receptor 2B activity promotes autonomous growth, migration as well as vascularization of head and neck squamous cell carcinoma cells.

Adenosine is a signaling molecule that exerts dual effects on tumor growth: while it inhibits immune cell function and thereby prevents surveillance by the immune system, it influences tumorigenesis directly via activation of adenosine receptors on tumor cells at the same time. However, the adenosine-mediated mechanisms affecting oncogenic processes particularly in head and neck squamous cell carcinomas (HNSCC) are not fully understood. Here, we investigated the role of adenosine receptor activity on HNSCC-derived cell lines. Targeting the adenosine receptor A2B (ADORA2B) on these cells with the inverse agonist/antagonist PSB-603 leads to inhibition of cell proliferation, transmigration as well as VEGFA secretion in vitro. At the molecular level, these effects were associated with cell cycle arrest as well as the induction of the apoptotic pathway. In addition, shRNA-mediated downmodulation of ADORA2B expression caused decreased proliferation. Moreover, in in vivo xenograft experiments, chemical and genetic abrogation of ADORA2B activity impaired tumor growth associated with decreased tumor vascularization. Together, our findings characterize ADORA2B as a crucial player in the maintenance of HNSCC and, therefore, as a potential therapeutic target for HNSCC treatment.

Adenosine-producing regulatory B cells in head and neck cancer.

BACKGROUND: Multiple mechanisms of immunosuppression have been identified in the tumor microenvironment including regulatory B cells (Breg). Recently, we have shown that Breg suppress T cell function by production of adenosine (ADO). However, the autocrine effect of ADO on B cells and the role of Breg in head and neck cancer remains unclear. METHODS: Blood (n = 42) and tumor tissue (n = 39) of head and neck cancer patients and healthy donors (n = 60) were analyzed by FACS. The effect of ADO on phenotype, intracellular signaling pathways, Ca2+ influx and ADO production was analyzed in Breg and effector B cells (Beff) by FACS, luminescence and mass spectrometry. The blockage of the ADO receptor A2A was analyzed in a murine head and neck cancer model. RESULTS: ADO-producing Breg were found in tumor tissue and peripheral blood. ADO inhibited the intracellular Bruton's tyrosine kinase (BTK) and Ca2+ influx only in Beff. The inhibition of BTK by ibrutinib mimicked the effect of ADO, and ibrutinib reduced the production of ADO by downregulation of CD39 in vitro. The inhibition of ADO receptor A2A significantly reduced tumor mass and increased B cell infiltration, in vivo. CONCLUSION: Our data demonstrate the presence of a novel ADO-producing Breg population within the tumor microenvironment in mice and humans. A new model is proposed on how ADO-producing Breg can influence the function of Beff cells in healthy donors and cancer patients. Thus, the modulation of the ADO pathway in B cells may serve as a therapeutic approach for cancer patients.

Comparative effectiveness trial of transoral head and neck surgery followed by adjuvant radio(chemo)therapy versus primary radiochemotherapy for oropharyngeal cancer (TopROC).

BACKGROUND: For loco-regionally advanced, but transorally resectable oropharyngeal cancer (OPSCC), the current standard of care includes surgical resection and risk-adapted adjuvant (chemo) radiotherapy, or definite chemoradiation with or without salvage surgery. While transoral surgery for OPSCC has increased over the last decade for example in the United States due to transoral robotic surgery, this treatment approach has a long history in Germany. In contrast to Anglo-Saxon countries, transoral surgical approaches have been used frequently in Germany to treat patients with oro-, hypopharyngeal and laryngeal cancer. Transoral laser microsurgery (TLM) has had a long tradition since its introduction in the early 70s. To date, the different therapeutic approaches to transorally resectable OPSCC have not been directly compared to each other in a randomized trial concerning disease control and survival. The goal of this study is to compare initial transoral surgery to definitive chemoradiation for resectable OPSCC, especially with regards to local and regional control. METHODS: TopROC is a prospective, two-arm, open label, multicenter, randomized, and controlled comparative effectiveness study. Eligible patients are ≥18 years old with treatment-naïve, histologically proven OPSCC (T1, N2a-c, M0; T2, N1-2c, M0; T3, N0-2c, M0 UICC vers. 7) which are amenable to transoral resection. Two hundred eighty patients will be randomly assigned (1:1) to surgical treatment (arm A) or chemoradiation (arm B). Standard of care treatment will be performed according to daily routine practice. Arm A consists of transoral surgical resection with neck dissection followed by risk-adapted adjuvant therapy. Patients treated in arm B receive standard chemoradiation, residual tumor may be subject to salvage surgery. Follow-up visits for 3 years are planned. Primary endpoint is time to local or locoregional failure (LRF). Secondary endpoints include overall and disease free survival, toxicity, and patient reported outcomes. Approximately 20 centers will be involved in Germany. This trial is supported by the German Cancer Aid and accompanied by a scientific support program. DISCUSSION: This study will shed light on an urgently-needed randomized comparison of the strategy of primary chemoradiation vs. primary surgical approach. As a comparative effectiveness trial, it is designed to provide data based on two established regimens in daily clinical routine. TRIAL REGISTRATION: NCT03691441 Registered 1 October 2018 - Retrospectively registered.

Characterization and Differentiation of the Tumor Microenvironment (TME) of Orthotopic and Subcutaneously Grown Head and Neck Squamous Cell Carcinoma (HNSCC) in Immunocompetent Mice.

For the development and evaluation of new head and neck squamous cell carcinoma (HNSCC) therapeutics, suitable, well-characterized animal models are needed. Thus, by analyzing orthotopic versus subcutaneous models of HNSCC in immunocompetent mice, we evaluated the existence of adenosine-related immunosuppressive B- and T lymphocyte populations within the tumor microenvironment (TME). Applying the SCC VII model for the induction of HNSCC in immunocompetent C3H/HeN mice, the cellular TME was characterized after tumor initiation over time by flow cytometry. The TME in orthotopic grown tumors revealed a larger population of tumor-infiltrating lymphocytes (TIL) with more B cells and CD4+ T cells than the subcutaneously grown tumors. Immune cell populations in the blood and bone marrow showed a rather distinct reaction toward tumor induction and tumor location compared to the spleen, lymph nodes, or thymus. In addition, large numbers of immunosuppressive B- and T cells were identified within the TME but also in secondary lymphoid organs, independently of the tumor initiation site. The altered immunogenic TME may influence the response to any treatment attempt. Moreover, when analyzing the TME and other lymphoid organs of tumor-bearing mice, we observed conditions reflecting largely those of patients suffering from HNSCC suggesting the C3H/HeN mouse model as a suitable tool for studies aiming to target immunosuppression to improve anti-cancer therapies.

NF-κB and Its Role in Checkpoint Control.

Nuclear factor-κB (NF-κB) has been described as one of the most important molecules linking inflammation to cancer. More recently, it has become clear that NF-κB is also involved in the regulation of immune checkpoint expression. Therapeutic approaches targeting immune checkpoint molecules, enabling the immune system to initiate immune responses against tumor cells, constitute a key breakthrough in cancer treatment. This review discusses recent evidence for an association of NF-κB and immune checkpoint expression and examines the therapeutic potential of inhibitors targeting either NF-κB directly or molecules involved in NF-κB regulation in combination with immune checkpoint blockade.

Immune Checkpoint Expression on Immune Cells of HNSCC Patients and Modulation by Chemo- and Immunotherapy.

Endogenous control mechanisms, including immune checkpoints and immunosuppressive cells, are exploited in the process of tumorigenesis to weaken the anti-tumor immune response. Cancer treatment by chemotherapy or immune checkpoint inhibition can lead to changes of checkpoint expression, which influences therapy success. Peripheral blood lymphocytes (PBL) and tumor-infiltrating lymphocytes (TIL) were isolated from head and neck squamous cell carcinoma (HNSCC) patients (n = 23) and compared to healthy donors (n = 23). Immune checkpoint expression (programmed cell death ligand 1 (PD-1), tumor necrosis factor receptor (TNFR)-related (GITR), CD137, tumor necrosis factor receptor superfamily member 4 (TNFRSF4) (OX40), t-cell immunoglobulin and mucin-domain containing-3 (TIM3), B- and T-lymphocyte attenuator (BTLA), lymphocyte-activation gene 3 (LAG3)) was determined on immune cells by flow cytometry. PD-L1 expression was detected on tumor tissue by immunohistochemistry. Immune cells were treated with immuno- and chemotherapeutics to investigate treatment-specific change in immune checkpoint expression, in vitro. Specific changes of immune checkpoint expression were identified on PBL and TIL of HNSCC patients compared to healthy donors. Various chemotherapeutics acted differently on the expression of immune checkpoints. Changes of checkpoint expression were significantly less pronounced on regulatory T cells compared to other lymphocyte populations. Nivolumab treatment significantly reduced the receptor PD-1 on all analyzed T cell populations, in vitro. The specific immune checkpoint expression patterns in HNSCC patients and the investigated effects of immunomodulatory agents may improve the development and efficacy of targeted immunotherapy.

Peripheral Cytokine Levels Differ by HPV Status and Change Treatment-Dependently in Patients with Head and Neck Squamous Cell Carcinoma.

Cytokines and immune mediators play an important role in the communication between immune cells guiding their response to infectious diseases or cancer. In this study, a comprehensive longitudinal analysis of serum cytokines and immune mediators in head and neck squamous cell carcinoma (HNSCC) patients was performed. In a prospective, non-interventional, longitudinal study, blood samples from 22 HNSCC patients were taken at defined time points (TP) before, during, and every 3 months after completion of (chemo)radio)therapy (CRT/RT) until 12 months after treatment. Serum concentrations of 17 cytokines/immune mediators and High-Mobility-Group-Protein B1 (HMGB1) were measured by fluorescent bead array and ELISA. Concentrations of sFas were significantly elevated during and after CRT/RT, whereas perforin levels were significantly decreased after CRT/RT. Levels of MIP-1ß and Granzyme B differed significantly during CRT/RT by HPV status. Increased HMGB1 levels were observed at recurrence, accompanied by high levels of IL-4 and IL-10. The sFas increase and simultaneous perforin decrease may indicate an impaired immune cell function during adjuvant radiotherapy. Increased levels of pro-inflammatory cytokines in HPV+ compared to HPV- patients seem to reflect the elevated immunogenicity of HPV-positive tumors. High levels of HMGB1 and anti-inflammatory cytokines at recurrence may be interpreted as a sign of immune evasion.

Patterns of antibody responses to nonviral cancer antigens in head and neck squamous cell carcinoma patients differ by human papillomavirus status.

There have been hints that nonviral cancer antigens are differentially expressed in human papillomavirus (HPV)-positive and HPV-negative head and neck squamous cell carcinoma (HNSCC). Antibody responses (AR) to cancer antigens may be used to indirectly determine cancer antigen expression in the tumor using a noninvasive and tissue-saving liquid biopsy. Here, we set out to characterize AR to a panel of nonviral cancer antigens in HPV-positive and HPV-negative HNSCC patients. A fluorescent microbead multiplex serology to 29 cancer antigens (16 cancer-testis antigens, 5 cancer-retina antigens and 8 oncogenes) and 29 HPV-antigens was performed in 382 HNSCC patients from five independent cohorts (153 HPV-positive and 209 HPV-negative). AR to any of the cancer antigens were found in 272/382 patients (72%). The ten most frequent AR were CT47, cTAGE5a, c-myc, LAGE-1, MAGE-A1, -A3, -A4, NY-ESO-1, SpanX-a1 and p53. AR to MAGE-A3, MAGE-A9 and p53 were found at significantly different prevalences by HPV status. An analysis of AR mean fluorescent intensity values uncovered remarkably different AR clusters by HPV status. To identify optimal antigen selections covering a maximum of patients with ≤10 AR, multiobjective optimization revealed distinct antigen selections by HPV status. We identified that AR to nonviral antigens differ by HPV status indicating differential antigen expression. Multiplex serology may be used to characterize antigen expression using serum or plasma as a tissue-sparing liquid biopsy. Cancer antigen panels should address the distinct antigen repertoire of HPV-positive and HPV-negative HNSCC.