Current studies of immunotherapy in head and neck cancer

Less is more: Exploring neoadjuvant immunotherapy as a de-escalation strategy in head and neck squamous cell carcinoma treatment

Head and neck squamous cell carcinoma (HNSCC) constitutes a significant global cancer burden, given its high prevalence and associated mortality. Despite substantial progress in survival rates due to the enhanced multidisciplinary approach to treatment, these methods often lead to severe tissue damage, compromised function, and potential toxicity. Thus, there is an imperative need for novel, effective, and minimally damaging treatment modalities. Neoadjuvant treatment, an emerging therapeutic strategy, is designed to reduce tumor size and curtail distant metastasis prior to definitive intervention. Currently, neoadjuvant chemotherapy (NACT) has optimized the treatment approach for a subset of HNSCC patients, yet it has not produced a noticeable enhancement in overall survival (OS). In the contemporary cancer therapeutics landscape, immunotherapy is gaining traction at an accelerated pace. Notably, neoadjuvant immunotherapy (NAIT) has shown promising radiological and pathological responses, coupled with encouraging efficacy in several clinical trials. This potentially paves the way for a myriad of possibilities in treatment de-escalation of HNSCC, which warrants further exploration. This paper reviews the existing strategies and efficacies of neoadjuvant immune checkpoint inhibitors (ICIs), along with potential de-escalation strategies. Furthermore, the challenges encountered in the context of the de-escalation strategies of NAIT are explored. The aim is to inform future research directions that strive to improve the quality of life (QoL) for patients battling HNSCC.

Tumoral P2Y2 receptor modulates tumor growth and host anti-tumor immune responses in a syngeneic murine model of oral cancer

Head and neck squamous cell carcinomas (HNSCCs) are a heterogenous group of tumors and among the top 10 most common cancers and they arise from the epithelial tissues of the mucosal surfaces of the oral cavity, oropharynx, and larynx. Aberrant purinergic signaling has been associated with various cancer types. Here, we studied the role of the P2Y2 purinergic receptor (P2Y2R) in the context of oral cancer. We utilized bioinformatics analysis of deposited datasets to examine purinome gene expression in HNSCC tumors and cells lines and functionally characterized nucleotide-induced P2 receptor signaling in human FaDu and Cal27 and murine MOC2 oral cancer cell lines. Utilizing tumorigenesis assays with wild-type or P2ry2 knockout MOC2 cells we evaluated the role of P2Y2Rs in tumor growth and the host anti-tumor immune responses. Our data demonstrate that human and murine oral cancer cell lines express numerous P2 receptors, with the P2Y2R being highly expressed. Using syngeneic tumor grafts in wild-type mice, we observed that MOC2 tumors expressing P2Y2R were larger than P2Y2R-/- tumors. Wild-type MOC2 tumors contained a lower population of tumor-infiltrating CD11b+F4/80+ macrophages and CD3+ cells, which were revealed to be CD3+CD4+IFNγ+ T cells, compared to P2Y2R-/- tumors. These results were mirrored when utilizing P2Y2R-/- mice, indicating that the changes in MOC2 tumor growth and to the host anti-tumor immune response were independent of host derived P2Y2Rs. Results suggest that targeted suppression of the P2Y2R in HNSCC cells in vivo, rather than systemic P2Y2R antagonism, may be a more effective treatment strategy for HNSCCs.

Role of Mesenchymal Stem/Stromal Cells in Head and Neck Cancer-Regulatory Mechanisms of Tumorigenic and Immune Activity, Chemotherapy Resistance, and Therapeutic Benefits of Stromal Cell-Based Pharmacological Strategies

Head and neck cancer (HNC) entails a heterogenous neoplastic disease that arises from the mucosal epithelium of the upper respiratory system and the gastrointestinal tract. It is characterized by high morbidity and mortality, being the eighth most common cancer worldwide. It is believed that the mesenchymal/stem stromal cells (MSCs) present in the tumour milieu play a key role in the modulation of tumour initiation, development and patient outcomes; they also influence the resistance to cisplatin-based chemotherapy, the gold standard for advanced HNC. MSCs are multipotent, heterogeneous and mobile cells. Although no MSC-specific markers exist, they can be recognized based on several others, such as CD73, CD90 and CD105, while lacking the presence of CD45, CD34, CD14 or CD11b, CD79α, or CD19 and HLA-DR antigens; they share phenotypic similarity with stromal cells and their capacity to differentiate into other cell types. In the tumour niche, MSC populations are characterized by cell quiescence, self-renewal capacity, low reactive oxygen species production and the acquisition of epithelial-to-mesenchymal transition properties. They may play a key role in the process of acquiring drug resistance and thus in treatment failure. The present narrative review examines the links between MSCs and HNC, as well as the different mechanisms involved in the development of resistance to current chemo-radiotherapies in HNC. It also examines the possibilities of pharmacological targeting of stemness-related chemoresistance in HNSCC. It describes promising new strategies to optimize chemoradiotherapy, with the potential to personalize patient treatment approaches, and highlights future therapeutic perspectives in HNC.

Therapeutic implications of signaling pathways and tumor microenvironment interactions in esophageal cancer

Esophageal cancer (EC) is significantly influenced by the tumor microenvironment (TME) and altered signaling pathways. Downregulating these pathways in EC is essential for suppressing tumor development, preventing metastasis, and enhancing therapeutic outcomes. This approach can increase tumor sensitivity to treatments, enhance patient outcomes, and inhibit cancer cell proliferation and spread. The TME, comprising cellular and non-cellular elements surrounding the tumor, significantly influences EC's development, course, and treatment responsiveness. Understanding the complex relationships within the TME is crucial for developing successful EC treatments. Immunotherapy is a vital TME treatment for EC. However, the heterogeneity within the TME limits the application of anticancer drugs outside clinical settings. Therefore, identifying reliable microenvironmental biomarkers that can detect therapeutic responses before initiating therapy is crucial. Combining approaches focusing on EC signaling pathways with TME can enhance treatment outcomes. This integrated strategy aims to interfere with essential signaling pathways promoting cancer spread while disrupting factors encouraging tumor development. Unraveling aberrant signaling pathways and TME components can lead to more focused and efficient treatment approaches, identifying specific cellular targets for treatments. Targeting the TME and signaling pathways may reduce metastasis risk by interfering with mechanisms facilitating cancer cell invasion and dissemination. In conclusion, this integrative strategy has significant potential for improving patient outcomes and advancing EC research and therapy. This review discusses the altered signaling pathways and TME in EC, focusing on potential future therapeutics.

Global research trends in immunotherapy for head and neck neoplasms: A scientometric study

In recent decades, the traditional treatment of head and neck neoplasms has reached a bottleneck with limited improvement in overall survival. Nevertheless, the emerging field of immunotherapy has shown promise. Literature on research into immunotherapy for head and neck neoplasms was retrieved from WoSCC. Citespace was used as a scientometric analysis tool for text mining and visualization of the scientific literature. This analysis included 1915 documents. Recently, the annual number of publications and citations has been growing rapidly. 'Oncology' was the most popular research area. The most dominant institution and country were the University of Pittsburgh and the USA. Ferris RL was not only the most prolific but also the most cited author, demonstrating a strong influence and reputation. Of the ten core journals identified in this field, Cancer Research ranked first. 'Regulatory T cell', 'PD-1' and 'biomarker' were regarded as current hotspots, while 'recurrent' and 'nivolumab' were considered as trending keywords. The most cited reference was Ferris RL (2016). Notably, the front trends and future directions in the field may lie in the clinical practice of combination therapy of immunotherapy plus other therapies, the mechanism of impaired immune surveillance, and the improvement in resistance to immunotherapeutic agents. It is firmly believed that the present scientometric analysis has provided both a macroscopic and microscopic overview of research into immunotherapy for head and neck neoplasms, which will assist researchers and oncologists to better understand this discipline and thus promote further development and policies in this field.

The Role of Different Immunocompetent Cell Populations in the Pathogenesis of Head and Neck Cancer-Regulatory Mechanisms of Pro- and Anti-Cancer Activity and Their Impact on Immunotherapy

Head and neck squamous cell carcinoma (HNSCC) is one of the most aggressive and heterogeneous groups of human neoplasms. HNSCC is characterized by high morbidity, accounting for 3% of all cancers, and high mortality with ~1.5% of all cancer deaths. It was the most common cancer worldwide in 2020, according to the latest GLOBOCAN data, representing the seventh most prevalent human malignancy. Despite great advances in surgical techniques and the application of modern combinations and cytotoxic therapies, HNSCC remains a leading cause of death worldwide with a low overall survival rate not exceeding 40-60% of the patient population. The most common causes of death in patients are its frequent nodal metastases and local neoplastic recurrences, as well as the relatively low response to treatment and severe drug resistance. Much evidence suggests that the tumour microenvironment (TME), tumour infiltrating lymphocytes (TILs) and circulating various subpopulations of immunocompetent cells, such regulatory T cells (CD4+CD25+Foxp3+Tregs), cytotoxic CD3+CD8+ T cells (CTLs) and CD3+CD4+ T helper type 1/2/9/17 (Th1/Th2/Th9/Th17) lymphocytes, T follicular helper cells (Tfh) and CD56dim/CD16bright activated natural killer cells (NK), carcinoma-associated fibroblasts (CAFs), myeloid-derived suppressor cells (MDSCs), tumour-associated neutrophils (N1/N2 TANs), as well as tumour-associated macrophages (M1/M2 phenotype TAMs) can affect initiation, progression and spread of HNSCC and determine the response to immunotherapy. Rapid advances in the field of immuno-oncology and the constantly growing knowledge of the immunosuppressive mechanisms and effects of tumour cancer have allowed for the use of effective and personalized immunotherapy as a first-line therapeutic procedure or an essential component of a combination therapy for primary, relapsed and metastatic HNSCC. This review presents the latest reports and molecular studies regarding the anti-tumour role of selected subpopulations of immunocompetent cells in the pathogenesis of HNSCC, including HPV+ve (HPV+) and HPV-ve (HPV-) tumours. The article focuses on the crucial regulatory mechanisms of pro- and anti-tumour activity, key genetic or epigenetic changes that favour tumour immune escape, and the strategies that the tumour employs to avoid recognition by immunocompetent cells, as well as resistance mechanisms to T and NK cell-based immunotherapy in HNSCC. The present review also provides an overview of the pre- and clinical early trials (I/II phase) and phase-III clinical trials published in this arena, which highlight the unprecedented effectiveness and limitations of immunotherapy in HNSCC, and the emerging issues facing the field of HNSCC immuno-oncology.

A Dual-Responsive STAT3 Inhibitor Nanoprodrug Combined with Oncolytic Virus Elicits Synergistic Antitumor Immune Responses by Igniting Pyroptosis

Immune checkpoint blockade (ICB) therapy shows excellent efficacy against malignancies; however, insufficient tumor immunogenicity and the immunosuppressive tumor microenvironment (TME) are considered as the two major stumbling blocks to a broad ICB response. Here, a combinational therapeutic strategy is reported, wherein TME-reactive oxygen species/pH dual-responsive signal transducers and activators of transcription 3 inhibitor nanoprodrugs MPNPs are combined with oncolytic herpes simplex virus 1 virotherapy to synergistically ignite pyroptosis for enhancing immunotherapy. MPNPs exhibit a certain level of tumor accumulation, reduce tumor cell stemness, and enhance antitumor immune responses. Furthermore, the simultaneous application of oncolytic viruses (OVs) confers MPNPs with higher tumor penetration capacity and remarkable gasdermin-E-mediated pyroptosis, thereby reshaping the TME and transforming "cold" tumors into "hot" ones. This "fire of immunity" strategy successfully activates robust T-cell-dependent antitumor responses, potentiating ICB effects against local recurrence and pulmonary metastasis in preclinical "cold" murine triple-negative breast cancer and syngeneic oral cancer models. Collectively, this work may pave a new way and offer an unprecedented opportunity for the combination of OVs with nanomedicine for cancer immunotherapy.

Increased response to TPF chemotherapy promotes immune escape in hypopharyngeal squamous cell carcinoma

Background: There is an urgent need to identify which patients would benefit from TPF chemotherapy in hypopharyngeal squamous cell carcinoma (HPSCC) and to explore new combinations to improve the treatment effect. Materials and methods: Gene-expression profiles in 15 TPF-sensitive patients were compared to 13 resistant patients. Immunohistochemistry (IHC) was performed to detect CD8⁺ T cells in 28 samples. Patient-Derived Tumor Xenograft (PDX) model and IHC were used to verify markers that optimize treatment for HPSCC. Results: Through RNA sequencing 188 genes were up-regulated in TPF chemotherapy-resistant (CR) tissues were involved in T cell activation, while 60 down-regulated genes were involved in glycolysis. Gene set enrichment analysis (GSEA) showed that chemotherapy-sensitive (CS) group upregulation of the pathways of glycolysis, while immune response was downregulated. CIBERSORT, MCP-counter, and IHC proved that most immune cells including CD8⁺ T cells in the CR significantly higher than that in CS group. Among the 16 up-regulated genes in CS had close associations, the most significant negative correlation between the gene level and CD8⁺ T cells existed in SEC61G. SEC61G was related to glycolysis, which was transcriptionally regulated by E2F1, and participated in antigen degradation through ubiquitin-dependent protein catabolic process. Palbociclib, combined with Cetuximab decreased the tumor burden and significantly suppressed the expression of E2F1 and SEC61G while activating MHC-I in PDX model. Conclusion: Enhanced glycolysis promoted immune escape, but increased response to TPF chemotherapy. SEC61G was the center of the molecular network and targeting the E2F1/SEC61G pathway increased the expression level of MHC-I.

Immunotherapy and Modern Radiotherapy Technique for Older Patients with Locally Advanced Head and Neck Cancer: A Proposed Paradigm by the International Geriatric Radiotherapy Group

The standard of care for locally advanced head and neck cancer is concurrent chemoradiation or postoperative irradiation with or without chemotherapy. Surgery may not be an option for older patients (70 years old or above) due to multiple co-morbidities and frailty. Additionally, the standard chemotherapy of cisplatin may not be ideal for those patients due to oto- and nephrotoxicity. Though carboplatin is a reasonable alternative for cisplatin in patients with a pre-existing hearing deficit or renal dysfunction, its efficacy may be inferior to cisplatin for head and neck cancer. In addition, concurrent chemoradiation is frequently associated with grade 3-4 mucositis and hematologic toxicity leading to poor tolerance among older cancer patients. Thus, a new algorithm needs to be developed to provide optimal local control while minimizing toxicity for this vulnerable group of patients. Recently, immunotherapy with check point inhibitors (CPI) has attracted much attention due to the high prevalence of program death-ligand 1 (PD-L1) in head and neck cancer. In patients with recurrent or metastatic head and neck cancer refractory to cisplatin-based chemotherapy, CPI has proven to be superior to conventional chemotherapy for salvage. Those with a high PD-L1 expression defined as 50% or above or a high tumor proportion score (TPS) may have an excellent response to CPI. This selected group of patients may be candidates for CPI combined with modern radiotherapy techniques, such as intensity-modulated image-guided radiotherapy (IM-IGRT), volumetric arc therapy (VMAT) or proton therapy if available, which allow for the sparing of critical structures, such as the salivary glands, oral cavity, cochlea, larynx and pharyngeal muscles, to improve the patients' quality of life. In addition, normal organs that are frequently sensitive to immunotherapy, such as the thyroid and lungs, are spared with modern radiotherapy techniques. In fit or carefully selected frail patients, a hypofractionated schedule may be considered to reduce the need for daily transportation. We propose a protocol combining CPI and modern radiotherapy techniques for older patients with locally advanced head and neck cancer who are not eligible for cisplatin-based chemotherapy and have a high TPS. Prospective studies should be performed to verify this hypothesis.

Oncologic outcomes of salvage surgery and immune checkpoint inhibitor therapy in recurrent head and neck squamous cell carcinoma: A single-institution retrospective study

BACKGROUND

Survival outcomes in recurrent head and neck squamous cell carcinoma (HNSCC) are poor. This study aimed to compare survival outcomes between salvage surgery and immunotherapy in patients with recurrent advanced HNSCC.

METHODS

Patients with advanced stage (stage III or IV) recurrent HNSCC following treatment with platinum-based chemotherapy were included. Survival was estimated using the Kaplan-Meier method, and Cox regression was used for multivariate logistic regression.

RESULTS

Two-year overall survival after salvage surgery was 68.6% and after immunotherapy patients was 24.6%. Multivariate logistic regression showed that salvage surgery was associated with improved survival without statistical significance (hazard ratio [HR] 0.12, p = 0.25). Subgroup analysis of patients with oral cavity/oropharyngeal cancer noted improved survival with salvage surgery over immunotherapy (HR 0.006, p = 0.01) and decreased survival with neutrophil-to-lymphocyte ratio (NLR) > 5 (HR 6.4, p = 0.02).

CONCLUSION

Our retrospective single-institutional data suggest that resectable advanced stage recurrent HNSCC may have improved survival with salvage surgery in appropriately selected patients, but larger prospective studies are required.

Association of immune response with overall and disease-free survival in laryngeal squamous cell carcinomas

OBJECTIVES

This study aimed to examine the relationship between checkpoint receptors (PD-1, PD-L1, PD-L2, CTLA-4) and lymphoid infiltration level (TILs) with prognostic features of patients with laryngeal squamous cell carcinoma (LSCC).

METHODS

A retrospective study was designed at a tertiary referential university hospital between April 2008 and December 2020. The surgical specimen of the patients who met the eligibility criteria were re-examined histopathological, sociodemographic, clinical, pathological, and follow-up findings of patients were determined. The impact of PD-1, PD-L1, PD-L2, CTLA4, and TILs levels for the presence of cancer recurrence, disease-specific mortality, overall survival (OS), disease-free survival (DFS) was investigated.

RESULTS

Forty-five patients with LSCC were included in the study. The mean follow-up period was 48.3 ± 14.3 months (min: 36, max 84). TILs scores were detected significantly lower in patients with distant metastasis and recurrence (p = 0.046 and 0.010). Also, only TILs was a significant risk factor for recurrence and survival among the PD-1, PD-L1, PD-L2, CTLA-4, and TILs (HR = 0.217 CI: 0.070-0.679, p = 0.009 and HR = 0.566, CI: 0,321-980, p = 0.048). Similarly, for the TILs score: > 1 was significant for DFS. (Long-Rank = 0.009). The examined markers and TILs scores were not a significant predictive factor for OS.

CONCLUSION

An increase in TILs density in LSCCs is associated with a better prognosis. However, PD-1, PD-L1, PD-L2, CTLA-4 could not be associated with prognosis. Controlled studies combined with immunotherapy treatment results are needed to reveal their role as a marker and prognostic factor of the anti-tumor immune response.

Delivery of an ectonucleotidase inhibitor with ROS-responsive nanoparticles overcomes adenosine-mediated cancer immunosuppression

Tumor evasion of immune destruction is associated with the production of immunosuppressive adenosine in the tumor microenvironment (TME). Anticancer therapies can trigger adenosine triphosphate (ATP) release from tumor cells, causing rapid formation of adenosine by the ectonucleotidases CD39 and CD73, thereafter exacerbating immunosuppression in the TME. The goal of this study was to develop an approach to facilitate cancer therapy-induced immunogenic cell death including ATP release and to limit ATP degradation into adenosine, in order to achieve durable antitumor immune response. Our approach was to construct reactive oxygen species (ROS)-producing nanoparticles that carry an ectonucleotidase inhibitor ARL67156 by electronic interaction and phenylboronic ester. Upon near-infrared irradiation, nanoparticle-produced ROS induced ATP release from MOC1 cancer cells in vitro and triggered the cleavage of phenylboronic ester, facilitating the release of ARL67156 from the nanoparticles. ARL67156 prevented conversion of ATP to adenosine and enhanced anticancer immunity in an MOC1-based coculture model. We tested this approach in mouse tumor models. Nanoparticle-based ROS-responsive drug delivery reprogramed the immunogenic landscape in tumors, eliciting tumor-specific T cell responses and tumor regression, conferring long-term survival in mouse models. We demonstrated that TME reprograming sets the stage for response to anti-programmed cell death protein 1 (PD1) immunotherapy, and the combination resulted in tumor regression in a 4T1 breast cancer mouse model that was resistant to PD1 blockade. Furthermore, our approach also induced immunological effects in patient-derived organotypic tumor spheroid model, suggesting potential translation of our nanoparticle approach for treating human cancers.

Immune checkpoint inhibitors in head and neck squamous cell carcinoma: A systematic review of phase-3 clinical trials

BACKGROUND

The outcomes of patients diagnosed with head and neck squamous cell carcinoma (HNSCC) who are not candidates for local salvage therapy and of those diagnosed with recurrent or metastatic disease are dismal. A relatively new systemic therapy option that emerged in recent years in the treatment of advanced HNSCC is immunotherapy using immune checkpoint inhibitors (ICIs). The safety profile and anti-tumor activity of these agents demonstrated in early phase clinical trials paved the way to the initiation of several promising phase-3 trials in the field.

AIM

To evaluate the evidence on the effectiveness of ICIs in HNSCC, based on published phase-3 clinical trials.

METHODS

We searched PubMed, Cochrane Library, Embase, and Scopus to identify published literature evaluating immunotherapy using ICIs in recurrent or metastatic HNSCC (R/M HNSCC) and locally advanced head and neck squamous cell carcinoma (LAHNSCC). We used a combination of standardized search terms and keywords including head and neck squamous cell carcinoma, recurrent, metastatic, locally advanced, immunotherapy, immune checkpoint inhibitors, monoclonal antibodies, programmed cell death protein-1 (PD-1), programmed death-ligand 1 (PD-L1), cytotoxic T- lymphocyte associated protein-4 (CTLA-4), and phase-3 clinical trial. A sensitive search filter was used to limit our results to randomized controlled trials.

RESULTS

Five phase-3 clinical trials have reported the data on the effectiveness of immunotherapy in HNSCC so far: Four in R/M HNSCC and one in LAHNSCC. In patients with R/M HNSCC, anti-PD-1 agents nivolumab and pembrolizumab demonstrated improved survival benefits in the second-line treatment setting compared to the standard of care (standard single-agent systemic therapy). While the net gain in overall survival (OS) with nivolumab was 2.4 mo [hazard ratio (HR) = 0.69, P = 0.01], that with pembrolizumab was 1.5 mo (HR = 0.80 nominal P = 0.0161). The anti-PD-L1 agent durvalumab with or without the anti-cytotoxic T- lymphocyte associated protein-4 agent tremelimumab did not result in any beneficial outcomes. In the first-line setting, in R/M HNSCC, pembrolizumab plus platinum-based chemotherapy resulted in significant improvement in survival with a net gain in OS of 2.3 mo (HR = 0.77, P = 0.0034) in the overall population and a net gain in OS of 4.2 mo in the PD-L1 positive (combined positive score > 20) population compared to standard of care (EXTREME regime). In patients with PD-L1 positive R/M HNSCC, monotherapy with pembrolizumab also demonstrated statistically significant improvement in survival compared to EXTREME. In LAHNSCC, immunotherapy using avelumab (an anti-PD-L1 agent) along with standard chemoradiation therapy did not result in improved outcomes compared to placebo plus chemoradiation therapy.

CONCLUSION

Anti-PD-1 agents provide survival benefits in R/M HNSCC in the first and second-line settings, with acceptable toxicity profiles compared to standard therapy. There is no proven efficacy in the curative setting to date.

Programmed death 1 (PD‐1) and ligand (PD‐L1) inhibitors in head and neck squamous cell carcinoma: A meta‐analysis

Background

PD‐1 and PD‐L1 inhibitors have emerged as promising treatments for patients with head and neck squamous cell carcinoma (HNSCC).

Methods

Systematic review and meta‐analysis of PD‐1 and PD‐L1 inhibitors in HNSCC. Outcomes: median overall survival (mOS), median progression‐free survival (mPFS), Response Evaluation Criteria in Solid Tumors (RECIST) and treatment‐related adverse events (TRAEs).

Results

Eleven trials reported data on 1088 patients (mean age: 59.9 years, range: 18–90). The total mOS was 7.97 months (range: 6.0–16.5). Mean mPFS for all studies was 2.84 months (range: 1.9–6.5). PD‐1 inhibitors had a lower rate of RECIST Progressive Disease than PD‐L1 inhibitors (42.61%, 95% confidence interval [CI]: 36.29–49.06 vs. 56.79%, 95% CI: 49.18–64.19, P < 0.001). The rate of TRAEs of any grade (62.7%, 95% CI: 59.8–65.6) did not differ.

Conclusions

Meta‐analysis shows the efficacy of PD‐1 and PD‐L1 inhibitors in HNSCC and suggests a possible difference in certain RECIST criterion between PD‐1 and PD‐L1 inhibitors. Future work to investigate the clinical significance of these findings is warranted.

Significant Findings of this Study: 11 studies were analyzed in this meta‐analysis of PD‐1 and PD‐L1 inhibitor use in head and neck squamous cell carcinoma. Data showed that PD‐1 inhibitors had a significantly lower rate of RECIST progressive disease when compared to PD‐L1 inhibitors.

What this study adds: Our meta‐analysis describes the efficacy of PD‐1 and PD‐L1 inhibitors in HNSCC and suggests a possible difference in certain RECIST criterion between PD‐1 and PD‐L1 inhibitors. This lays foundation for future work to guide clinical treatment of HNSCC.

A Novel Immune-Associated Gene Signature for Overall Survival Prediction in Patients with Oral Squamous Cell Carcinoma

Objective

To explore a novel Immune-associated gene signature for overall survival (OS) in patients with oral squamous cell carcinoma (OSCC).

Methods

Expression profiles of genes and corresponding clinical materials of OSCC patients were obtained through the TCGA database. With a LASSO Cox regression model, a multigene signature was established to predict the OS of OSCC patients. Some molecular experiments including RNA interference, MTT, and Transwell assay were applied to verify the role of the risk gene FGF9 in OSCC.

Results

43 immune-related prognostic DEGs were identified in OSCC. A 17-gene signature was established to assign the patients to either a high-risk group (HG) or a low-risk group (LG). The HG presented a shorter OS than the LG (P < 0.05). According to multivariate Cox regression analyses, the risk score was considered an independent factor for OS prediction (training set: HR = 3.485, 95% CI = 2.037-5.961, P < 0.001; test set: HR = 4.531, 95% CI = 2.120-9.682, P < 0.001). ROC curve-based analysis revealed the signature's ability for prediction. According to functional analysis, the immune cell expression and immune function of the HG were significantly inhibited. After knocking down the high-risk gene FGF9, the migration, proliferation, and invasion capabilities of OSCC cells HSC6 were significantly suppressed (P < 0.05).

Conclusion

A novel immune-associated gene signature was identified for predicting the prognosis of OSCC. These risk genes show great potential as targets for OSCC treatment.

Comprehensive Analysis of Tumor Immune Microenvironment Characteristics for the Prognostic Prediction and Immunotherapy of Oral Squamous Cell Carcinoma

Background: Oral squamous cell carcinoma (OSCC) is the most common cancer of oral and maxillofacial region. A recent clinical research has shown that tumor immune microenvironment (TIME)cells are closely related to immunotherapy sensitivity and OSCC prognosis. Nonetheless, a comprehensive analysis of TIME in OSCC has not been reported.

Methods: Bioinformatics and computational algorithms were employed to determine the significance of TIME cells in 257 OSCC patients. TIME scores were measured by three TIME models, and then used to evaluate the prognosis of OSCC patients.

Results: High TIME score was characterized by better prognosis in OSCC patients less than 60 years old, overexpression of immunotherapy targets (e.g., PD-1 and CLTA-4), and higher T-cell activity to inhibit tumor growth. Besides, poor prognosis was associated with low time score.

Conclusion: TIME score exhibited potential as a prognostic biomarker and an indicator in predict immunotherapeutic outcomes. Through the understanding of TIME model, this study can provide a better scheme for immunotherapy as the effective treatment of OSCC patients in the future.

Roles of mesenchymal stromal cells in the head and neck cancer microenvironment

Head and neck cancer (HNC), a common malignancy worldwide, is associated with high morbidity and mortality rates. Squamous cell carcinoma is the most common HNC type, followed by salivary gland carcinomas, head and neck sarcomas, and lymphomas. The microenvironment of HNCs comprises various cells that regulate tumor development. Recent studies have reported that the tumor microenvironment, which modulates cancer progression, regulates cancer treatment response. However, the presence of different types of stromal cells in cancers is a major challenge to elucidate the role of individual cells in tumor progression. The role of mesenchymal stromal cells (MSCs), which are a component of the tumor microenvironment, in HNC is unclear. The major impediment for characterizing the role of MSCs in cancer progression is the lack of MSC-specific markers and their phenotypic similarity with stromal cells. This review aimed to summarize the latest findings on the role of MSCs in the progression of HNC to improve our understanding of HNC pathophysiology.

Sex differences in the behavioral and immune responses of mice to tumor growth and cancer therapy

There is significant variability in the expression of cancer-related fatigue. Understanding the factors that account for this variation provide insight into the underlying mechanisms. One important, but often overlooked, variable is biological sex. While a few clinical studies have indicated that female patients report higher levels of fatigue, these studies are subject to potential socio-culture reporting biases. Only a limited number of preclinical studies have considered sex differences in animal model of fatigue and few have simultaneously considered both disease- and treatment-related factors. The present series of studies was initiated to address the current knowledge gap on the importance of sex differences in cancer-related fatigue. We selected a murine model of human papilloma virus-positive head and neck cancer based on heterotypic injection of the mEERL95 cell line that grows in both male and female mice and responds to a regimen of cisplatin plus irradiation. We also tested the impact of immunotherapy treatment targeting PD1. Voluntary wheel running was used to evaluate fatigue-like behavior. Male mice grew larger tumors than did female mice and showed more severe fatigue-like behavior. We confirmed that the tumor increased the expression of inflammatory cytokines in the liver, but no sex differences were observed. As a trend toward elevated Cd3 mRNA was observed in female mice, we tested the importance of T cells using female Rag2-/- mice. The Rag2-/- female mice had accelerated tumor growth and more severe fatigue-like behavior. In response to cisplatin alone non-tumor-bearing female mice showed a slower recovery of wheel running activity compared to males. However, in response to chemoradiation and anti-PD1 neutralizing antibody, tumor-bearing female mice showed a better tumor response to therapy than male mice, but no significant sex differences were observed for wheel running. These findings point to different mechanisms underlying tumor- and treatment-induced behavioral fatigue and indicate that the sex factor can intervene to modulate the expression of fatigue-like behavior in particular circumstances.

Defining the Role of Immunotherapy in the Curative Treatment of Locoregionally Advanced Head and Neck Cancer: Promises, Challenges, and Opportunities

Recent advancements in the development of immunotherapies have raised the hope for patients with locally-advanced HNSCC (LA-HNSCC) to achieve improved oncologic outcomes without the heavy burden of treatment-related morbidity. While there are several ongoing late phase clinical trials that seek to determine whether immunotherapy can be effectively employed in the definitive setting, initial results from concurrent immuno-radiotherapy therapy trials have not shown strong evidence of benefit. Encouragingly, evidence from preclinical studies and early-phase neoadjuvant studies have begun to show potential pathways forward, with therapeutic combinations and sequences that intentionally spare tumor draining lymphatics in order to maximize the synergy between definitive local therapy and immunotherapy. The intent of this review is to summarize the scientific rationale and current clinical evidence for employing immunotherapy for LA-HNSCC as well as the ongoing efforts and challenges to determine how to optimally deliver and sequence immunotherapy alongside traditional therapeutics. In both the preclinical and clinical settings, we will discuss the application of immunotherapies to both surgical and radiotherapeutic management of HNSCC.

The Potential Impact and Usability of the Eighth Edition TNM Staging Classification in Oral Cavity Cancer

AIMS

In the current eighth edition head and neck TNM staging, extranodal extension (ENE) is an adverse feature in oral cavity squamous cell cancer (OSCC). The previous seventh edition N1 with ENE is now staged as N2a. Seventh edition N2+ with ENE is staged as N3b in the eighth edition. We evaluated its potential impact on patients treated with surgery and postoperative intensity-modulated radiotherapy (IMRT).

MATERIALS AND METHODS

OSCC patients treated with primary surgery and adjuvant (chemo)radiotherapy between January 2005 and December 2014 were reviewed. Cohorts with pathological node-negative (pN-), pathological node-positive without ENE (pN+_pENE-) and pathological node-positive with ENE (pN+_pENE+) diseases were compared for local control, regional control, distant control and overall survival. The pN+ cohorts were further stratified into seventh edition N-staging subgroups for outcomes comparison.

RESULTS

In total, 478 patients were evaluated: 173 pN-; 159 pN+_pENE-; 146 pN+_pENE+. Outcomes at 5 years were: local control was identical (78%) in all cohorts (P = 0.892), whereas regional control was 91%, 80% and 68%, respectively (P < 0.001). Distant control was 97%, 87%, 68% (P < 0.001) and overall survival was 75%, 53% and 39% (P < 0.001), respectively. Overall survival for N1 and N2a subgroups was not significantly different. In the seventh edition N2b subgroup of pENE- (n = 79) and pENE+ (n = 79) cohorts, overall survival was 67% and 37%, respectively. In the seventh edition N2c subgroups, overall survival for pENE- (n = 17) and pENE+ (n = 38) cohorts was 65% and 35% (P = 0.08), respectively. Overall, an additional 128 patients (42% pN+) were upstaged as N3b.

CONCLUSIONS

When eighth edition staging was applied, stage migration across the N2-3 categories resulted in expected larger separations of overall survival by stage. Patients treated with primary radiation without surgical staging should have outcomes carefully monitored. Strategies to predict ENE preoperatively and trials to improve the outcomes of pENE+ patients should be explored.

Artificial Intelligence and Radiomics in Head and Neck Cancer Care: Opportunities, Mechanics, and Challenges

The advent of large-scale high-performance computing has allowed the development of machine-learning techniques in oncologic applications. Among these, there has been substantial growth in radiomics (machine-learning texture analysis of images) and artificial intelligence (which uses deep-learning techniques for "learning algorithms"); however, clinical implementation has yet to be realized at scale. To improve implementation, opportunities, mechanics, and challenges, models of imaging-enabled artificial intelligence approaches need to be understood by clinicians who make the treatment decisions. This article aims to convey the basic conceptual premises of radiomics and artificial intelligence using head and neck cancer as a use case. This educational overview focuses on approaches for head and neck oncology imaging, detailing current research efforts and challenges to implementation.

The immunotherapeutic role of indoleamine 2,3-dioxygenase in head and neck squamous cell carcinoma: A systematic review

BACKGROUND

Novel cancer immunotherapy seeks to harness the body's own immune system and tip the balance in favour of antitumour activity. The intracellular enzyme indoleamine 2,3-dioxygenase (IDO) is a critical regulator of the tumour microenvironment (TME) via tryptophan metabolism. The potential immunotherapeutic role of IDO in head and neck squamous cell carcinoma (HNSCC) requires further exploration. We aim to assess the evidence on IDO in HNSCC.

METHODS

A systematic review of literature and clinical trials databases.

RESULTS

We included 40 studies: seven involved cell lines: eight assessed tumour immunohistochemistry: ten measured IDO gene transcription: 15 reported on clinical trials. Increased cell line IDO expression was postulated to adversely affect tumour metabolism and apoptosis. Immunohistochemical IDO expression correlated with worse survival. Gene transcription studies associated IDO with positive PD-L1 and human papillomavirus (HPV) status. Phase I/II clinical trials showed (a) overall response (34%-55%) and disease control rates (62%-70%) for IDO1 inhibitor in combination with a PD-1 inhibitor, (b) similar safety profiles when both are used in combination therapy compared to each as monotherapies and (c) IDO gene expression as a predictive biomarker for response to PD-L1 therapy.

CONCLUSIONS

IDO expression is increased in the TME of HNSCC, which correlates with poor prognosis. However, the exact mechanism of IDO-driven immune modulation in the TME is an enigma. Future translational studies should map IDO activity during HNSCC treatment and elucidate its precise role in the TME, such research will underpin the development of clinical trials establishing the efficacy of IDO inhibitors in HNSCC.

Novel Prognostic Model Based on Immune Signature for Head and Neck Squamous Cell Carcinoma

Background

Deciphering the immune characteristics within tumors and identifying the immune signals related to the prognostic factor are helpful for the treatment and management of tumor patients. However, systematic analysis of immune signatures in head and neck squamous cell carcinoma (HNSCC) remains largely unstudied.

Methods

A total of 718 immune-related genes were extracted from RNA sequencing data from 519 HNSCC patients in the TCGA database, and survival analysis with integrated bioinformatics analyses was performed to build the final predictive prognosis model.

Results

The 178 survival-associated genes (P < 0.05) participated in important immune functions, including immune cell activation and migration. Multivariate regression analysis using 93 genes (P < 0.01), together with survival-associated clinicopathological parameters, identified 35 independent prognostic factors. The most significant 8 independent factors were CD3E, CD40LG, TNFRSF4, CD3G, CD5, ITGA2B, ABCB1, and TNFRSF13b. The final prognostic model achieved outstanding predictive efficiency with the highest AUC of 0.963.

Conclusion

Our prognostic model based on the immune signature could effectively predict the prognosis of HNSCC patients, providing novel predictive biomarkers and potential therapeutic targets for HNSCC patients.

Microneedles loaded with anti-PD-1-cisplatin nanoparticles for synergistic cancer immuno-chemotherapy

Programmed cell death protein-1 (PD-1) on T-cells combined with programmed cell death ligand-1 (PD-L1) critically accounts for tumor immune evasion. Anti-PD-1 (aPD-1) blocks the binding of PD-1 to PD-L1, thus allowing T-cell activation for tumor cell eradication. Currently, the major challenges for cancer immunotherapy are how to improve the response rate and overcome drug resistance. Dermal administration turns out to be a promising route for immunotherapy since skin is a highly active immune organ containing a large population of resident antigen-presenting cells. Microneedle arrays can pierce the immune-cell-rich epidermis, leading to a robust T-cell response in the microenvironment of tumor cells. Herein, we successfully developed a microneedle patch loaded with pH-responsive tumor-targeted lipid nanoparticles (NPs), which allows local delivery of aPD-1 and cisplatin (CDDP) precisely to cancer tissues for cancer therapy. For in vivo studies, aPD-1/CDDP@NPs delivered through microneedles effectively boosted the immune response, thereby a remarkable effect on tumor regression was realized. Synergistic anticancer mechanisms were therefore activated through robust microneedle-induced T-cell response, blockage of PD-1 in T-cells by aPD-1, and an increase in direct cytotoxicity of CDDP in tumor cells. Strikingly, transdermal delivery using MNs increased the response rate in the animal model unresponsive to aPD-1 systemic therapy. This exhibited promise in the treatment of immunotherapy-unresponsive cancers. Taken together, microneedle-mediated local delivery of nano-encapsulated chemotherapeutic and immunotherapeutic agents at tumor skin sites provides a novel treatment strategy and insights into cancer therapy.

Inflammatory Myeloradiculitis Secondary to Pembrolizumab: A Case Report and Literature Review

Immune checkpoint inhibitors are the most important new medications in oncology and include inhibitors of programmed cell death protein-1 (PD-1) such as Pembrolizumab, Nivolumab, and Cemiplimab. These anticancer agents prevent tumour immune evasion and have been associated with a range of immune-related adverse events (irAEs) including those involving the nervous system. In this case report and literature review, we present the first case of inflammatory myeloradiculitis secondary to Pembrolizumab. We also summarise the characteristics, treatment, and outcomes of other cases reported in the literature which include a component of myelitis. Finally, we make general recommendations on management.

Prognostic impact of PD-L1 in oropharyngeal cancer after primary curative radiotherapy and relation to HPV and tobacco smoking

Background: Incidence of oropharyngeal squamous cell carcinoma (OPSCC) is rising rapidly in many western countries due to Human papillomavirus (HPV) and tobacco smoking, with a considerable overlap. Immunotherapy directed at the PD1/PD-L1 axis have shown promise in head and neck cancer and other cancer types. PD-L1 expression may indicate a poorer prognosis, and at the same time indicate a possible benefit of anti-PD-L1 immunotherapeutic agents. The primary aim of this study was to establish the prognostic effect of PD-L1 expression after primary curative radiotherapy alone.Material and methods: A cohort of 303 OPSCC patients treated with primary, curative intended radiotherapy was established. PD-L1 expression was evaluated by immunohistochemistry on formalin fixed, paraffin embedded tissue sections. PD-L1 positivity was defined as a Combined Positive Score (CPS) ≥1, indicating staining of either tumor cells, lymphocytes or macrophages.Results: Median follow-up was 5.3 years. With 199 deaths, there was no difference in overall survival between patients with PD-L1+ and PD-L1- tumors (adjusted hazard ratio [aHR] and 95% confidence interval [CI]: 1.0 [0.71-1.4]). Also, locoregional failure was similar between the two groups (aHR 1.1 [CI: 0.68 - 1.7]). Tumors were PD-L1+ in 76% of cases, significantly more among HPV p16+ tumors (82% vs. 70%, p = .01). Interestingly, higher prevalence of PD-L1+ expression was seen in HPV p16+ patients with <10 pack-years of tobacco-smoking (93%) compared to HPV p16+ smokers (76%) or HPV p16-negative patients (70%) (p = .003).Conclusion: PD-L1 expression had no prognostic significance in OPSCC patients treated with primary radiotherapy alone. A substantial proportion of OPSCC tumors show PD-L1 overexpression, especially in HPV p16+ tumors in patients with little or no smoking history.

The Current Landscape of Immune Checkpoint Inhibition for Solid Malignancies

Immunotherapy has led to unprecedented improvement in the treatment and prognosis of high-risk resectable and metastatic disease across cancer types. Nowhere is this better highlighted than in the management of advanced and metastatic melanoma with the introduction of molecularly targeted therapies and immune checkpoint inhibitors. Following their success in melanoma, immunotherapies have also been evaluated and their use approved in the management across a variety of other solid malignancies in the neoadjuvant, adjuvant, and advanced/metastatic setting. This review provides an overview of the current landscape of immune checkpoint inhibition for solid malignancies.

Real-world treatment patterns for patients with metastatic head and neck squamous cell carcinoma treated with immuno-oncology therapy

BACKGROUND

Real-world use of immuno-oncology (IO) therapies (nivolumab and pembrolizumab) in metastatic head and neck squamous cell carcinoma (mHNSCC) has not been well studied.

METHODS

mHNSCC patients treated with an IO therapy were identified from a large US claims database from 2016 to 2017. Treatment patterns before and after initiation of IO therapy (index date) were described.

RESULTS

Among 416 mHNSCC patients, 85% had ≥1 regimen prior to IO therapy. Ninety-seven percent of patients initiated IO as monotherapy and 3% initiated IO combined with another systemic treatment. One hundred seventeen (28%) patients had a subsequent regimen, usually chemotherapy (n = 58, 50%) or IO monotherapy (n = 27, 23%), of which 22 patients restarted the same IO therapy and 5 switched to another IO monotherapy.

CONCLUSION

The majority of mHNSCC patients initiated IO as a monotherapy. Approximately half of patients with a subsequent regimen received chemotherapy and one-fourth received IO monotherapy.

Biological Determinants of Chemo-Radiotherapy Response in HPV-Negative Head and Neck Cancer: A Multicentric External Validation

Purpose: Tumor markers that are related to hypoxia, proliferation, DNA damage repair and stem cell-ness, have a prognostic value in advanced stage HNSCC patients when assessed individually. Here we aimed to evaluate and validate this in a multifactorial context and assess interrelation and the combined role of these biological factors in determining chemo-radiotherapy response in HPV-negative advanced HNSCC. Methods: RNA sequencing data of pre-treatment biopsy material from 197 HPV-negative advanced stage HNSCC patients treated with definitive chemoradiotherapy was analyzed. Biological parameter scores were assigned to patient samples using previously generated and described gene expression signatures. Locoregional control rates were used to assess the role of these biological parameters in radiation response and compared to distant metastasis data. Biological factors were ranked according to their clinical impact using bootstrapping methods and multivariate Cox regression analyses that included clinical variables. Multivariate Cox regression analyses comprising all biological variables were used to define their relative role among all factors when combined. Results: Only few biomarker scores correlate with each other, underscoring their independence. The different biological factors do not correlate or cluster, except for the two stem cell markers CD44 and SLC3A2 (r = 0.4, p < 0.001) and acute hypoxia prediction scores which correlated with T-cell infiltration score, CD8⁺ T cell abundance and proliferation scores (r = 0.52, 0.56, and 0.6, respectively with p < 0.001). Locoregional control association analyses revealed that chronic (Hazard Ratio (HR) = 3.9) and acute hypoxia (HR = 1.9), followed by stem cell-ness (CD44/SLC3A2; HR = 2.2/2.3), were the strongest and most robust determinants of radiation response. Furthermore, multivariable analysis, considering other biological and clinical factors, reveal a significant role for EGFR expression (HR = 2.9, p < 0.05) and T-cell infiltration (CD8⁺T-cells: HR = 2.2, p < 0.05; CD8⁺T-cells/Treg: HR = 2.6, p < 0.01) signatures in locoregional control of chemoradiotherapy-treated HNSCC. Conclusion: Tumor acute and chronic hypoxia, stem cell-ness, and CD8⁺ T-cell parameters are relevant and largely independent biological factors that together contribute to locoregional control. The combined analyses illustrate the additive value of multifactorial analyses and support a role for EGFR expression analysis and immune cell markers in addition to previously validated biomarkers. This external validation underscores the relevance of biological factors in determining chemoradiotherapy outcome in HNSCC.

Immunotherapy in the management of squamous cell carcinoma of the head and neck

Despite many advances in surgery, radiotherapy, and systemic treatments, only modest improvements in survival, function, and quality of life have been achieved after treatment of squamous cell carcinoma (SCC) of the head and neck. With a better understanding of the biology and genetics of tumours, the emergence of a paradigm shift towards the further development of non-surgical treatments may result in less morbidity and better outcomes than are seen currently. SCC of the head and neck is known to be a complex disease that has a sophisticated interaction with the human immune system. At the forefront of emerging treatments is immunotherapy, which has already been established in many other areas of oncology. The rapidly evolving nature of immunotherapeutic agents and, sometimes, their complex mechanisms can make the understanding of these concepts challenging, and could discourage clinicians from engaging in clinical trials. The aim of this paper therefore was to review the current premise for immunotherapeutic approaches, and to provide a contemporary evidence-based rationale for their use.

Immune Checkpoint Inhibitor Toxicity in Head and Neck Cancer: From Identification to Management

Benefiting from the continuously clarifying underlying biology of immune checkpoints and ligand–receptor interactions, the emergence of new anticancer treatment strategy, immunotherapy has shown substantial benefits on several liquid and solid tumors. Immune checkpoint inhibitors (ICIs) can block the negative regulatory components and enhance the T cell function, thus leading to prominent anticancer activity. On account of their promising effect on various malignancies shown in clinical trials, ICIs have been considered to be the most potent anticancer agents in the near future. Head and neck cancer is the seventh most common neoplasm worldwide, and the gross 5-year survival rate was only 60%. Managing locoregionally advanced, recurrent, or metastatic head and neck tumors is still a challenging problem for both oncologists and surgeons. Recent clinical trials employing the immune-modulating antibodies that target cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) and programmed cell death 1 (PD-1) herald a new era of anticancer therapy. However, like all other anticancer drugs, ICIs also have side effects while upregulating the immune system to enhance antitumor response, which were known as immune-related adverse events (irAEs). Generally, most irAEs were transient, but sometimes they can cause serious organ dysfunction, even fatal. In addition, due to the distinct anatomical feature, advanced head and neck tumors often affect the upper aerodigestive tract and cause serious dyspnea or dysphagia. Toxicities of ICIs may be more lethal for such patients. Thus, with the increasing application of anti-checkpoint agents in head and neck cancer, there is urgent need to ascertain the safety of this novel treatment strategy. Here, we compile this review of existing clinical trials on the toxicity of ICIs during cancer treatment. The particular clinical manifestation, characteristics of complication development in fatal cases, and the management strategies were discussed. This may provide vital information for future oncology trials and clinical practice.

Targeting interferon signaling and CTLA-4 enhance the therapeutic efficacy of anti-PD-1 immunotherapy in preclinical model of HPV+ oral cancer

Background

The US is experiencing an epidemic of HPV⁺ oropharyngeal cancers (OPC), the rates and burden of which now exceed that for cervical cancer. Immunotherapy targeting programmed death 1 (PD-1) on tumor-infiltrating lymphocytes and/or its ligand PD-L1 on tumor cells, which was effective in several cancers has however, showed efficacy in only less than 15% of patients.

Methods

We used a preclinical HPV⁺ oral tumor model, mEER, consisting of mouse tonsil derived epithelial cells expressing HPV-16 E6 and E7 genes, along with the H-ras oncogene to test strategies for enhancing the efficacy of anti-PD-1 therapy.

Results

Monotherapy with PD-1 blocking antibody was ineffective against flank-implanted tumors, but induced regression in 54% of mice bearing orthotopic tongue tumors that correlated with higher CD8 T cell responses. Since the CD8⁺ T cells derived from tongue tumors also showed high levels of the immune checkpoint inhibitory receptor CTLA-4, we tested combination immunotherapy targeting both CTLA-4 and PD-1 together and observed 93.3% survival of mice bearing tumors in the tongue for the duration of our 100-day study. Protective immunity correlated with a significant decrease in immunosuppressive lymphoid and myeloid populations within the tumor microenvironment. Consistent with the reported capacity of interferon-driven PD-L1/PD-1 pathway induction to serve as a biomarker of response to PD-1 blockade, we observed elevated interferon signaling and significantly higher levels of PD-1/PD-L1 in tongue-implanted mEER tumors compared to those growing on the flank correlating with their preferential responsiveness to PD-1 blockade. More importantly, in a pseudometastasic mouse model bearing both flank and tongue tumors to represent metastatic disease, delivery of Stimulator of Interferon Induced Genes (STING) agonist into the flank tumors combined with systemic treatment with α-PD-1 and α-CTLA-4 antibodies resulted in sustained tumor regression in 71% of mice. In this case, productive abscopal anti-tumor immunity was associated with robust increases in the ratios of cytotoxic CD8⁺ T cells (CTL) versus regulatory T cells (Treg) and versus functional myeloid-derived suppressor cells (MDSC).

Conclusions

These results support combining α-PD-1 therapy with induction of IFN-α/β signaling via provision of STING agonist and/or through CTLA-4 blockade as potential treatment option for HNSCC patients, especially, those not responding to α-PD-1 monotherapy.

The relevance between the immune response-related gene module and clinical traits in head and neck squamous cell carcinoma

Purpose

Head and neck squamous cell carcinoma (HNSCC) is the sixth most prevalent cancer in the world, accounting for more than 90% of head and neck malignant tumors. However, its molecular mechanism is largely unknown. To help elucidate the potential mechanism of HNSCC tumorigenesis, we investigated the gene interaction patterns associated with tumorigenesis.

Methods

Weighted gene co-expression network analysis (WGCNA) can help us to predict the intrinsic relationship or correlation between gene expression. Additionally, we further explored the combination of clinical information and module construction.

Results

Sixteen modules were constructed, among which the key module most closely associated with clinical information was identified. By analyzing the genes in this module, we found that the latter may be related to the immune response, inflammatory response and formation of the tumor microenvironment. Sixteen hub genes were identified-ARHGAP9, SASH3, CORO1A, ITGAL, PPP1R16B, TBC1D10C, IL10RA, ITK, AKNA, PRKCB, TRAF3IP3, GIMAP4, CCR7, P2RY8, GIMAP7, and SP140. We further validated these genes at the transcriptional and translation levels.

Conclusion

The innovative use of a weighted network to analyze HNSCC samples provides new insights into the molecular mechanism and prognosis of HNSCC. Additionally, the hub genes we identified can be used as biomarkers and therapeutic targets of HNSCC, laying the foundation for the accurate diagnosis and treatment of HNSCC in clinical and research in the future.

Intratumoral delivery of an HPV vaccine elicits a broad anti-tumor immune response that translates into a potent anti-tumor effect in a preclinical murine HPV model

Therapeutic cancer vaccines have met limited clinical success. In the setting of cancer, the immune system is either tolerized and/or has a limited tumor-specific T cell repertoire. In this study, we explore whether intratumoral (IT) vaccination with an HPV vaccine can elicit quantitative and qualitative differences in immune response as compared to intramuscular (IM) vaccination to overcome immune resistance in established tumors. We report that IT administration of an HPV-16 E7 peptide vaccine formulated with polyinosinic-polycytidylic acid [poly(I:C)] generated an enhanced antitumor effect relative to IM delivery. The elicited anti-tumor effect with IT vaccination was consistent among the vaccinated groups and across various C57BL/6 substrains. IT vaccination resulted in an increased frequency of PD-1^hi TILs, which represented both vaccine-targeted and non-vaccine-targeted tumor-specific CD8⁺ T cells. Overall, the CD8⁺/Treg ratio was increased within the tumor microenvironment using IT vaccination. We also assessed transcriptional changes in several immune-related genes in the tumor microenvironment of the various treated groups, and our data suggest that IT vaccination leads to upregulation of a broad complement of immunomodulatory genes, including upregulation of interferon gamma (IFNγ) and antigen presentation and processing machine (APM) components. IT vaccine delivery is superior to traditional IM vaccination routes with the potential to improve tumor immunogenicity, which has potential clinical application in the setting of accessible lesions such as head and neck squamous cell carcinomas (HNSCCs).

Treatment trends in head and neck cancer: Surveillance, Epidemiology, and End Results (SEER) Patterns of Care analysis

PURPOSE

Recent advances in head and neck cancer (HNC) treatment, such as increased use of organ-preserving advanced radiation treatments, the approval of cetuximab for HNC treatment, and the increase in human papillomavirus (HPV)-related HNC, have changed clinical approaches to HNC management. We sought to identify treatment trends in a population-based cohort of HNC patients.

METHODS

The Surveillance, Epidemiology, and End Results Patterns of Care program collected additional treatment and HPV testing information on stratified random samples of HNC patients diagnosed in 1997 (n = 473), 2004 (n = 1,317), and 2009 (n = 1,128). Rao-Scott Chi-square tests were used to examine unadjusted associations between year of diagnosis and patient sociodemographic, tumor, and treatment characteristics. Cochran-Armitage tests for trend were used to examine the hypothesis that certain treatments were used increasingly (or decreasingly) over the time period, while logistic regression was used to examine factors associated with particular treatments.

RESULTS

Use of radiation and chemotherapy without surgery significantly increased for all HNC sites between 1997 and 2009. Cetuximab and taxane use also showed a significantly increasing trend. Lack of insurance was associated with not receiving treatment in multivariate models. The majority (64%) of cases undergoing radiation in 2009 received an advanced treatment, with 55% receiving intensity modulated. The majority of oropharyngeal cases with known HPV status received chemotherapy and radiation only (62%) and nearly all were insured and had one or fewer comorbidities.

CONCLUSIONS

Treatment patterns have changed for HNC, leading to increased incorporation of systemic therapy and newer radiation techniques. HPV testing should be targeted for more widespread use, especially in traditionally underserved groups.

Overcoming Radioresistance: Small Molecule Radiosensitisers and Hypoxia-activated Prodrugs

The role of hypoxia in radiation resistance is well established and many approaches to overcome hypoxia in tumours have been explored, with variable success. Two small molecule strategies for targeting hypoxia have dominated preclinical and clinical efforts. One approach has been the use of electron-affinic nitroheterocycles as oxygen-mimetic sensitisers. These agents are best exemplified by the 5-nitroimidazole nimorazole, which has limited use in conjunction with radiotherapy in head and neck squamous cell carcinoma. The second approach seeks to leverage tumour hypoxia as a tumour-specific address for hypoxia-activated prodrugs. These prodrugs are selectively activated by reductases under hypoxia to release cytotoxins, which in some instances may diffuse to kill surrounding oxic tumour tissue. A number of these hypoxia-activated prodrugs have been examined in clinical trial and the merits and shortcomings of recent examples are discussed. There has been an evolution from delivering DNA-interactive cytotoxins to molecularly targeted agents. Efforts to implement these strategies clinically continue today, but success has been elusive. Several issues have been identified that compromised these clinical campaigns. A failure to consider the extravascular transport and the micropharmacokinetic properties of the prodrugs has reduced efficacy. One key element for these 'targeted' approaches is the need to co-develop biomarkers to identify appropriate patients. Hypoxia-activated prodrugs require biomarkers for hypoxia, but also for appropriate activating reductases in tumours, as well as markers of intrinsic sensitivity to the released drug. The field is still evolving and changes in radiation delivery and the impact of immune-oncology will provide fertile ground for future innovation.

Real-world treatment patterns and outcomes of patients with stage IV squamous cell carcinoma of the head and neck

Aim: To understand the treatment patterns and outcomes for stage IV squamous cell carcinoma of the head and neck, patients receiving second-line or later drug therapy. Materials & methods: Real-world data were collected from 1152 patients in the USA, France, Germany and the UK through a retrospective chart analysis and patient-reported outcomes were collected using validated questionnaires in a subgroup of patients. Results: Forty-four percent of patients had stage IVA/B disease. A total of 77, 19 and 3% of patients had received two, three and four plus lines of active drug treatment. Platinum- and cetuximab-based regimens were common at early treatment lines. Time to progression was short (5.2 months post first line), survival rates low and patient-reported health status poor. Conclusion: Novel therapies that could improve clinical and patient-reported outcomes would address a significant unmet need.

Immune-relevant aspects of murine models of head and neck cancer

Head and neck cancers (HNCs) cause significant mortality and morbidity. There have been few advances in therapeutic management of HNC in the past 4 to 5 decades, which support the need for studies focusing on HNC biology. In recent years, increased recognition of the relevance of the host response in cancer progression has led to novel therapeutic strategies and putative biomarkers of tumor aggressiveness. However, tumor-immune interactions are highly complex and vary with cancer type. Pre-clinical, in vivo models represent an important and necessary step in understanding biological processes involved in development, progression and treatment of HNC. Rodents (mice, rats, hamsters) are the most frequently used animal models in HNC research. The relevance and utility of information generated by studies in murine models is unquestionable, but it is also limited in application to tumor-immune interactions. In this review, we present information regarding the immune-specific characteristics of the murine models most commonly used in HNC research, including immunocompromised and immunocompetent animals. The particular characteristics of xenograft, chemically induced, syngeneic, transgenic, and humanized models are discussed in order to provide context and insight for researchers interested in the in vivo study of tumor-immune interactions in HNC.

Characteristics and impact of programmed death-ligand 1 expression, CD8+ tumor-infiltrating lymphocytes, and p16 status in head and neck squamous cell carcinoma

BACKGROUND

No predictive biomarker of immune checkpoint inhibitors in head and neck squamous cell carcinoma (HNSCC) has been well established. The impact of programmed death-ligand 1 (PD-L1) expression, CD8+ tumor-infiltrating lymphocytes (TILs), and p16 status in HNSCC is unclear and may vary according to ethnicity.

METHODS

HNSCC patients treated between 2007 and 2013 were reviewed. Archival tissues were retrieved for PD-L1, CD8+ TILs, and p16 analyses. PD-L1 expression was evaluated by using the validated SP142 assay on the VENTANA platform. CD8+ TILs were defined by using semiquantitative scoring.

RESULTS

A total of 203 patients were analyzed. PD-L1 expression was observed in 80% of patients and was significantly associated with older age (P < 0.001). A high CD8+ TIL score (≥ 6) was significantly associated with never-smoking (P = 0.020), oral cavity cancer (P < 0.001), and stage M0 at presentation (P = 0.025). The p16 status was positive in 12% of patients. Patients with a high TIL score had a significantly longer OS (P = 0.032). Patients with PD-L1 expression of 1-49% and ≥ 50% were associated with a significantly shorter OS compared with those with PD-L1 < 1% (P = 0.027 and P = 0.011, respectively). Multivariate analysis showed that PD-L1 ≥ 50% was significantly associated with a poor OS. (HR 2.98 [95% CI 1.2-7.39]; P = 0.019.) CONCLUSIONS: A high prevalence of PD-L1 expression was observed in HNSCC using the validated SP142 assay. PD-L1 expression was associated with older age, while highly PD-L1 expression (≥ 50%) was an independent prognostic factor for poor OS in anti-PD1/PD-L1 untreated HNSCC patients.

An update: emerging drugs to treat squamous cell carcinomas of the head and neck

Introduction: Subsequent to the 2006 FDA approval of cetuximab, a variety of molecular targeting agents have been evaluated in head and neck squamous cell carcinoma (HNSCC). The treatment outcomes of recurrent and/or metastatic (R/M) HNSCC, in particular, remain dismal. The 2016 FDA approval of PD-1 immune checkpoint inhibitors has expanded the treatment options for R/M HNSCC and highlights the potential for immune-based therapies. Areas covered: We will review the clinical application of EGFR-targeted agents, alone and in combination with other drugs. Molecular targeting agents directed against the IL6/PI3K/STAT3 signaling pathway will be covered. In addition, evaluation of immune checkpoint inhibitors in HNSCC, along with ongoing combination trials incorporating these agents, will be discussed. The expanded indications of emerging drugs and the potential clinical benefit of new drugs and treatment combinations will be summarized. Expert opinion: In recent years, there has been a major shift toward immunotherapy-based approaches for the treatment of HNSCC, leading to significant improvements in outcomes for a subset of patients. Leveraging the increased understanding of the genetic alterations that characterize individual HNSCC tumors will facilitate precision medicine approaches using targeted agents, immunotherapies, as well as standard chemotherapy and radiation.

[IoNESCO trial: Immune neoajuvant therapy in early stage non-small cell lung cancer]

BACKGROUND

Programmed cell death-ligand 1 (PD-L1) is a checkpoint receptor that facilitates immune evasion by tumor cells, through interaction with programmed cell death-1 (PD-1), a receptor expressed by T-cells. Durvalumab is an anti-PD-L1 monoclonal antibody that blocks PD-L1 interaction with PD-1 on T-cells, countering the tumor's immune-evading tactics. Phase I/II studies demonstrated durable responses and manageable tolerability in heavily pre-treated patients with non-small cell lung cancer (NSCLC).

METHODS

This phase II study is designed to administrate three durvalumab IV infusions (10mg/kg at day 1, 15, 29) before surgery, to patients with pathologically confirmed NSCLC, clinical stage IB (>4cm) or stage II, ≥18 years of age, WHO performans status 0-1, without selection on PD-L1 expression. Preoperative chemotherapy and radiation therapy are not permitted. The primary objective is feasibility of complete surgical resection. Major pathological response on surgical tissue, defined as 10% or less remaining tumor cells, will be a secondary objective. Additional secondary objectives include tolerance, adverse effects, delay between start of treatment and surgery, response rate (RECIST 1.1), metabolic response rate, postoperative adverse events, disease-free survival and overall survival. A rate of complete resection<85% (P0) is considered unacceptable. P1 hypothesis is of 95%, and with a study power of 90% and an alpha risk of 5% (two-steps Fleming's procedure), 81 patients are required.

EXPECTED RESULTS

To establish whether neoadjuvant immunotherapy is feasible and could improve the survival of patients with early-stage NSCLC.

Recent advances in the understanding and management of oropharyngeal cancer

Oropharyngeal squamous cell carcinoma (OPSCC) is an increasing health problem in the developing and developed world. In recent years, there have been major changes in the treatment paradigms for OPSCC. This is because of a number of reasons: the understanding and discovery of a new viral etiology (the human papillomavirus [HPV]), changes in practice patterns owing to advances in radiotherapy, and then an organ preservation strategy with the increased use of chemotherapy. Next came the development of new surgical technologies and the emergence of a new treatment modality, immunotherapy. In this article, we discuss the evolution of OPSCC treatments, starting with the traditional tobacco era. Treatment paradigms then evolved during the organ preservation era, the HPV era, and the minimally invasive surgery era. We are currently in the immunotherapy era, with a number of new drugs becoming available both on trial and by approval for use in the clinical setting for head and neck cancer patients. We discuss a number of trials and the reasons behind attempts at both treatment escalation and treatment de-escalation.

A Non Platinum Regimen for the Treatment of Recurrent or Metastatic Squamous Cell Carcinoma of the Head and Neck Region. Results From an Extended Phase II Study With Paclitaxel and Capecitabine

Background

This study presents the results of an extended phase II study originally published in 2007, regarding the antitumor activity and toxicity of a non-platinum containing regimen with paclitaxel and capecitabine for the treatment of recurrent or disseminated squamous cell carcinoma of the head and neck region. Fifty patients were included in the original study.

Materials and methods

A total of 183 patients with recurrent or disseminated squamous cell carcinoma were eventually included in the extended study. There were 37 women and 146 men. The mean age was 56 years. Performance status (WHO) was as follows: WHO 0:31, WHO 1:107, and WHO 2:45 patients. The treatment consisted of paclitaxel 175 mg/m², once every third week and capecitabine 825 mg/m² p.o. b.i.d for 2 weeks.

Results

The overall response rate (complete response and partial response) according to the WHO criteria was: 33% (CI 26–40). The median progression-free survival was 4.8 (CI 4.2–5.4) months. The median overall survival (OS) was 8.9 (CI 7.6–9.5) months. Compliance was good. Of the 1,131 cycles, only 13% had to be administered with a reduced dose and/or postponed to a later date. Toxicity was mild and grades 3 and 4 toxicities were uncommon. Two toxic deaths were registered though.

Conclusion

The response rate and the OS for this low toxicity regimen makes it a feasible alternative for not cisplatin eligible patients.

[Immunotherapy - The New Era of Oncology]

In the field of immunotherapy, essential progress was achieved over the past years partially demonstrating long lasting therapeutic responses in different tumor entities. A better understanding of the interactions between the tumor and the immune system as well as the integration of immunotherapeutic approaches into clinical routine were the foundations for this development. The different approaches intervene on multiple levels of the immune response and directly or indirectly mount the patient‘s own immune defense against tumor cells. Immunotherapeutic approaches are represented by cytokine therapies, vaccinations, the use of oncolytic viruses and monoclonal antibody therapies as well as adoptive cell transfer strategies.

Mouse Models for Studying Oral Cancer: Impact in the Era of Cancer Immunotherapy

Model systems for oral cancer research have progressed from tumor epithelial cell cultures to in vivo systems that mimic oral cancer genetics, pathological characteristics, and tumor-stroma interactions of oral cancer patients. In the era of cancer immunotherapy, it is imperative to use model systems to test oral cancer prevention and therapeutic interventions in the presence of an immune system and to discover mechanisms of stromal contributions to oral cancer carcinogenesis. Here, we review in vivo mouse model systems commonly used for studying oral cancer and discuss the impact these models are having in advancing basic mechanisms, chemoprevention, and therapeutic intervention of oral cancer while highlighting recent discoveries concerning the role of immune cells in oral cancer. Improvements to in vivo model systems that highly recapitulate human oral cancer hold the key to identifying features of oral cancer initiation, progression, and invasion as well as molecular and cellular targets for prevention, therapeutic response, and immunotherapy development.

Circulating tumour cell PD-L1 test for head and neck cancers

Immune checkpoint inhibitors have gained traction over the last few years in the treatment of metastatic/recurrent head and neck squamous cell carcinoma (HNSCC) patients. Monoclonal antibodies that block the programmed death 1 (PD-1) receptor and its major ligand, PD-L1, have shown durable responses and low toxicity profiles. There are currently no validated predictive biomarkers to select patients likely to respond to anti-PD-1/PD-L1 therapy to avoid unwanted side effects and to reduce healthcare expenditure. A circulating tumour cell (CTC) PD-L1 assay could be developed as a companion diagnostic tool to potentially predict the efficacy of immune checkpoint blockade treatments.