Response and recurrence correlates in individuals treated with neoadjuvant anti-PD-1 therapy for resectable oral cavity squamous cell carcinoma

Immunohistochemistry for Skin Cancers: A Comprehensive Approach to the Diagnosis of Squamous Cell Carcinoma

BACKGROUND

Squamous cell carcinoma (SCC) is a heterogeneous group of epithelial malignancies with varied morphologies and clinical behaviors. While histopathology is the diagnostic gold standard, it can be limited in distinguishing SCC from morphologic mimics. Immunohistochemistry (IHC) has therefore become a critical adjunct, enhancing diagnostic accuracy and providing prognostic insights.

OBJECTIVE

This narrative review aims to evaluate the diagnostic, differential, and prognostic roles of commonly used IHC markers in SCC, with particular emphasis on their utility in distinguishing SCC from histologic mimickers across different anatomical sites.

METHODS

One hundred and five peer-reviewed articles were analyzed for their relevance to the immunohistochemical characterization of SCC. Markers were categorized based on their diagnostic function, role in differential diagnosis, and prognostic value.

RESULTS

Key markers such as p40, p63, CK5/6, and DSG3 consistently demonstrated high sensitivity and specificity for SCC, reinforcing their value in confirming squamous differentiation. Conversely, exclusion markers like Ber-EP4, CK7, TTF-1, S100, and SOX10 were essential in ruling out basal cell carcinoma, adenocarcinoma, and melanoma. Additionally, markers such as Ki-67, p16, and CD44 offered prognostic information regarding tumor aggressiveness, HPV status, and therapy response. These findings confirm the critical role of IHC not only in diagnosing SCC but also in resolving complex differential diagnoses.

CONCLUSIONS

IHC markers serve as indispensable tools in the diagnostic workup of SCC, particularly in distinguishing it from other neoplasms with overlapping histologic features. The clear correlation between marker expression and diagnostic categories supports the systematic use of IHC to improve diagnostic precision and inform prognosis. Future integration with molecular diagnostics may further refine personalized treatment approaches in SCC.

Induced B cell receptor diversity predicts PD-1 blockade immunotherapy response

Immune checkpoint inhibitors such as anti-Programmed Death-1 antibodies (aPD-1) can be effective in treating advanced cancers. However, many patients do not respond, and the mechanisms underlying these differences remain incompletely understood. In this study, we profile a cohort of patients with locally advanced or metastatic basal cell carcinoma undergoing aPD-1 therapy using single-cell RNA sequencing, high-definition spatial transcriptomics in tumors and draining lymph nodes, and spatial immunoreceptor profiling, with long-term clinical follow-up. We find that successful responses to PD-1 inhibition are characterized by an induction of B cell receptor (BCR) clonal diversity after treatment initiation. These induced BCR clones spatially colocalize with T cell clones, facilitate their activation, and traffic alongside them between tumor and draining lymph nodes to enhance tumor clearance. Furthermore, we validated aPD-1-induced BCR diversity as a predictor of clinical response in a larger cohort of glioblastoma, melanoma, and head and neck squamous cell carcinoma patients, suggesting that this is a generalizable predictor of treatment response across many types of cancers. We find that pretreatment tumors harbor a characteristic gene expression signature that portends a higher probability of inducing BCR clonal diversity after aPD-1 therapy, and we develop a machine learning model that predicts PD-1-induced BCR clonal diversity from baseline tumor RNA sequencing. These findings underscore a dynamic role of B cell diversity during immunotherapy, highlighting its importance as a prognostic marker and a potential target for intervention in non-responders.

Nivolumab resistance in head and neck squamous cell carcinoma patients and future perspectives

Head and neck cancer (HNC) cases are increasing globally, with resistance to immunotherapies such as nivolumab posing a significant challenge. This systematic review examines the mechanisms of nivolumab resistance in HNC, with a focus on intrinsic tumor factors, the immunosuppressive tumor microenvironment (TME), and immune checkpoint dysregulation. Intrinsic mechanisms, such as mutations that impair antigen presentation and MYC amplification, reshape the TME to promote immune evasion. The tumor microenvironment, enriched with immunosuppressive cells such as tumor-associated macrophages and myeloid-derived suppressor cells, further compromises nivolumab's effectiveness. Moreover, cancer cells exploit immune checkpoints, including programmed death-ligand 1 (PD-L1), T-cell immunoglobulin and mucin domain-3, and LAG-3, to evade immune surveillance. Identifying predictive biomarkers, such as MYC amplification and PD-L1 expression, is essential for developing personalized treatments. This review underscores the complex nature of nivolumab resistance and the urgent need for comprehensive therapeutic strategies to improve outcomes in HNC patients.

CDKN2A Low cancer cells outcompete macrophages for microenvironmental zinc to drive immunotherapy resistance

Approximately 50% of cancers exhibit decreased CDKN2A expression ( CDKN2A Low ), which is linked to immune checkpoint blockade (ICB) resistance. While CDKN2A is traditionally recognized as a tumor suppressor and cell cycle regulator, we have previously put forth a new paradigm demonstrating its role in intracellular metabolic reprogramming. Whether the metabolic derangement due to CDKN2A loss alters metabolites within the tumor microenvironment (TME) and how that affects the immune compartment and ICB response has never been investigated. Here we found that CDKN2A Low cancer cells reorganize zinc compartmentalization by upregulating the zinc importer SLC39A9 in the plasma membrane, leading to intracellular zinc accumulation in cancer cells and concurrent zinc depletion in the TME. This competition for zinc results in zinc-starved tumor-associated macrophages (TAMs), leading to reduced phagocytic activity. Increasing zinc in TAMs through multiple approaches, including a dietary intervention that increases availability of TME zinc, re-educates these TAMs to a pro-phagocytic phenotype. Remarkably, both knockdown of Slc39a9 in cancer cells or providing a high zinc diet sensitizes Cdkn2a Low tumors to ICB. TAMs, not T cells, are indispensable for ICB response. Clinically, TAMs from CDKN2A Low cancer patients have decreased zinc signatures, corresponding to reduced phagocytosis signatures. Moreover, patients with low circulating zinc levels have reduced time-to-event outcomes compared to those with higher zinc levels. Our work reveals a previously unrecognized mechanism through which CDKN2A Low cancer cells outcompete TAMs for zinc, directly disrupting their function and ICB efficacy.

Neoadjuvant and Adjuvant Immunotherapy in the Treatment of Oral Squamous Cell Carcinoma

Oral squamous cell carcinoma (OSCC) is experiencing a progressive increase in global incidence. Regrettably, this entity is typically discovered at an advanced stage in the majority of patients, which indicates increased therapeutic challenges and a poorer prognosis. Programmed cell death protein 1 (PD-1) appears to have a significant role in immunotherapy and monoclonal antibodies targeting this molecule have been utilized as a therapeutic intervention. A decade of research indicates that neoadjuvant immunotherapy has garnered greater interest than adjuvant immunotherapy in OSCC. This may be due to neoadjuvant immunotherapy serving as a preventive and adjunctive treatment. Enhanced outcomes may be achieved by optimizing the cancer microenvironment before surgery. Of note, neoadjuvant immunotherapy has been introduced preoperatively for untreated OSCC.

Metal-dependent cell death resistance contribute to lymph node metastasis of oral squamous cell carcinoma

Objectives

Ferroptosis and cuproptosis can be summarized as metal-dependent cell death. This study aimed to explore the expression of metal-dependent cell death resistance (MCDR) characteristics in tumor cells of oral squamous cell carcinoma (OSCC) and to explore its relationship with lymph node metastasis (LNM).

Methods

By integrating single-cell data of OSCC from public databases, an expression matrix comprising 127,149 cells was constructed. Gene set scores were calculated using the irGSEA package, and GO and KEGG analyses were performed to identify enriched pathways. The R package monocle3 was employed to calculate the cell trajectory and infer evolutionary patterns. The MuSiC2 package was employed to enable the evaluation of cell proportions. Cell-cell interaction information was analyzed using the CellChat package. The expression of cathepsin V (CTSV), glutathione peroxidase 4 (GPX4), and cyclin-dependent kinase inhibitor 2A (CDKN2A) was validated via immunohistochemistry and multiplex immunohistochemistry in oral mucosa (OM), non-metastatic primary tumors (nPT), and metastatic primary tumors (mPT). Additionally, R package oncoPredict was utilized to identify potential drug sensitivities.

Results

The malignant cells in OSCC were divided into five subtypes, among which Epi_2 existed more in mPT and had higher MCDR characteristics. In addition, Epi_2 enriched multiple malignant-related pathways such as HEDGEHOG, NOTCH, and MYC. The spatial transcriptome and bulk RNA data verified that the proportion of Epi_2 in mPT was higher than that in nPT. Cell communication analysis showed that the effect of Epi_2 on endothelial cells was enhanced, which was mainly reflected in VEGFR and CXCL signaling pathways. Immunohistochemical results showed that the expression of Epi_2 characteristic markers CTSV and GPX4 in mPT was significantly higher than that in nPT. Multiplex immunohistochemical results showed that the co-expression cells of CTSV, GPX4 and CDKN2A in mPT were more than those in nPT. OSCC patients with high Epi_2 characteristics may have immunotherapy resistance and anti-EGFR treatment resistance. Doramapimod was identified as a sensitive drug.

Conclusion

There is a type of malignant cells with characteristics of MDCR in OSCC, which is related to LNM and treatment resistance. It provides a predictive marker for early diagnosis of LNM.

Loss of JAK1 Function Causes G2/M Cell Cycle Defects Vulnerable to Kif18a Inhibition

To gain insight into biological mechanisms that cause resistance to DNA damage, we performed parallel pooled genetic CRISPR-Cas9 screening for survival in high risk HNSCC subtypes. Surprisingly, and in addition to ATM, DNAPK, and NFKB signaling, JAK1 was identified as a driver of tumor cell radiosensitivity. Knockout of JAK1 in HNSCC increases cell survival by enhancing the DNA damage-induced G2 arrest, and both knockout and JAK1 inhibition with abrocitinib prevent subsequent formation of radiation-induced micronuclei. Loss of JAK1 function does not affect canonical CDK1 signaling but does reduce activation of PLK1 and AURKA, kinases that regulate both G2 and M phase progression. Correspondingly, JAK1 KO was found to cause mitotic defects using both EdU labeling and live cell imaging techniques. Given this insight, we evaluated Kif18a inhibition as an approach to exacerbate mitotic stress and enhance the efficacy of radiation. These studies establish Kif18a inhibition as a novel strategy to counteract therapeutic resistance to DNA damage mediated by G2 cell cycle arrest.

Efficacy, safety, and multi-omics analysis of pembrolizumab combined with nab-paclitaxel and platinum as first-line treatment in patients with recurrent or metastatic head and neck squamous cell carcinoma: A single-arm phase 2 study

Objective

Based on the findings of the KEYNOTE-048 study, pembrolizumab in combination with platinum and fluorouracil is the standard first-line treatment for recurrent or metastatic head and neck squamous cell carcinoma (R/M HNSCC). The efficacy and safety of pembrolizumab combined with nab-paclitaxel and platinum in such patients remain unexplored.

Methods

This single-arm phase 2 study enrolled patients with R/M HNSCC who received pembrolizumab (200 mg), nab-paclitaxel (260 mg/m²), and either cisplatin (75 mg/m²) or carboplatin [area under the curve (AUC) 5] every 21 d for up to six cycles, followed by pembrolizumab maintenance therapy. The primary endpoint was the objective response rate (ORR). Secondary endpoints included disease control rate (DCR), progression-free survival (PFS), duration of response (DoR), overall survival (OS), and safety. Exploratory multi-omics analyses were conducted.

Results

Between April 23, 2021, and August 20, 2023, a total of 67 patients with R/M HNSCC were enrolled and received the study treatment. By the data cut-off date of March 2, 2024, 62 (92.5%) patients had received cisplatin, while five (7.5%) patients had received carboplatin. The median follow-up duration was 12.7 (range: 2.3-34.8) months. The ORR was 62.7%, and the DCR was 88.1%. The median PFS, DoR, and OS were 9.7, 13.0, and 18.7 months, respectively. The most common grade 3 adverse events (AEs) were leukopenia (22.4%) and neutropenia (28.4%). Genomic alterations correlated with efficacy outcomes, and dynamic changes in 17 plasma proteins were associated with treatment response. Upregulation of serum interferon (IFN)-γ and interleukin (IL) 8 levels was linked to treatment-related AEs.

Conclusions

Pembrolizumab in combination with nab-paclitaxel and platinum demonstrated promising efficacy and a manageable safety profile in patients with R/M HNSCC. Future studies are warranted to confirm these findings.

Role of PD-1/PD-L1 signaling axis in oncogenesis and its targeting by bioactive natural compounds for cancer immunotherapy

Cancer is a global health problem and one of the leading causes of mortality. Immune checkpoint inhibitors have revolutionized the field of oncology, emerging as a powerful treatment strategy. A key pathway that has garnered considerable attention is programmed cell death-1 (PD-1)/programmed cell death ligand-1 (PD-L1). The interaction between PD-L1 expressed on tumor cells and PD-1 reduces the innate immune response and thus compromises the capability of the body's immune system. Furthermore, it controls the phenotype and functionality of innate and adaptive immune components. A range of monoclonal antibodies, including avelumab, atezolizumab, camrelizumab, dostarlimab, durvalumab, sinitilimab, toripalimab, and zimberelimab, have been developed for targeting the interaction between PD-1 and PD-L1. These agents can induce a broad spectrum of autoimmune-like complications that may affect any organ system. Recent studies have focused on the effect of various natural compounds that inhibit immune checkpoints. This could contribute to the existing arsenal of anticancer drugs. Several bioactive natural agents have been shown to affect the PD-1/PD-L1 signaling axis, promoting tumor cell apoptosis, influencing cell proliferation, and eventually leading to tumor cell death and inhibiting cancer progression. However, there is a substantial knowledge gap regarding the role of different natural compounds targeting PD-1 in the context of cancer. Hence, this review aims to provide a common connection between PD-1/PD-L1 blockade and the anticancer effects of distinct natural molecules. Moreover, the primary focus will be on the underlying mechanism of action as well as the clinical efficacy of bioactive molecules. Current challenges along with the scope of future research directions targeting PD-1/PD-L1 interactions through natural substances are also discussed.

Induced B-Cell Receptor Diversity Predicts PD-1 Blockade Immunotherapy Response

Immune checkpoint inhibitors such as anti-PD-1 antibodies (aPD1) can be effective in treating advanced cancers. However, many patients do not respond and the mechanisms underlying these differences remain incompletely understood. In this study, we profile a cohort of patients with locally-advanced or metastatic basal cell carcinoma undergoing aPD-1 therapy using single-cell RNA sequencing, high-definition spatial transcriptomics in tumors and draining lymph nodes, and spatial immunoreceptor profiling, with long-term clinical follow-up. We find that successful responses to PD-1 inhibition are characterized by an induction of B-cell receptor (BCR) clonal diversity after treatment initiation. These induced BCR clones spatially co-localize with T-cell clones, facilitate their activation, and traffic alongside them between tumor and draining lymph nodes to enhance tumor clearance. Furthermore, we validated aPD1-induced BCR diversity as a predictor of clinical response in a larger cohort of glioblastoma, melanoma, and head and neck squamous cell carcinoma patients, suggesting that this is a generalizable predictor of treatment response across many types of cancers. We discover that pre-treatment tumors harbor a characteristic gene expression signature that portends a higher probability of inducing BCR clonal diversity after aPD-1 therapy, and we develop a machine learning model that predicts PD-1-induced BCR clonal diversity from baseline tumor RNA sequencing. These findings underscore a dynamic role of B cell diversity during immunotherapy, highlighting its importance as a prognostic marker and a potential target for intervention in non-responders.

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

OBJECTIVE

This meta-analysis aims to evaluate the efficacy and safety of antiprogressive disease (PD)-(L)1-based neoadjuvant therapy in head and neck squamous cell carcinoma (HNSCC) patients and identify potential prognostic biomarkers.

DATA SOURCES

Databases were systematically searched for prospective clinical trials evaluating the efficacy and safety of anti-PD-(L)1-based neoadjuvant therapy for HNSCC before January 12, 2024.

REVIEW METHODS

We estimated the efficacy and safety of neoadjuvant immune checkpoint inhibitors. Subgroup and sensitivity analyses were further performed.

RESULTS

A total of 570 patients from 20 studies were included. The pooled major pathological response (MPR), pathological complete response (pCR), and partial pathological response (PPR) rates were 30.7%, 15.3%, and 68.2%, respectively. Surgical complications, surgical delayed rate, all grade treatment-related adverse effects (TRAEs) and ≥Grade 3 TRAEs were 0.6%, 0.3%, 82.6%, and 9.7%, respectively. Best MPR or pCR rate was detected in patients receiving neoadjuvant anti-PD-(L)1 therapy + radiotherapy (with MPR rate of 75.5% and pCR rate of 51.1%) and neoadjuvant anti-PD-(L)1 therapy + chemotherapy groups (with MPR rate of 57.5% and pCR rate of 26.7%). No differences were detected in subgroups stratified by neoadjuvant treatment cycles, human papillomavirus (HPV) status, and tumor location. Patients with baseline Combined Positive Score (CPS) ≥ 20 have higher MPR and pCR rates compared to patients with CPS < 20. High Tumor Cell Proportion Score was also associated with MPR and pCR. Objective response rate is a strong predictor of MPR (odds ratio [OR] = 7.78, 95% confidence interval [CI] = 3.20%-18.91%) and pCR (OR = 3.24, 95% CI = 1.40%-7.48%).

CONCLUSION

Anti-PD-(L)1-based neoadjuvant therapy was effective and safe for HNSCC patients.

TCRosetta: An Integrated Analysis and Annotation Platform for T-cell Receptor Sequences

T cells and T-cell receptors (TCRs) are essential components of the adaptive immune system. Characterization of the TCR repertoire offers a promising and highly informative source for understanding the functions of T cells in the immune response and immunotherapy. Although TCR repertoire studies have attracted much attention, there are few online servers available for TCR repertoire analysis, especially for TCR sequence annotation or advanced analyses. Therefore, we developed TCRosetta, a comprehensive online server that integrates analytical methods for TCR repertoire analysis and visualization. TCRosetta combines general feature analysis, large-scale sequence clustering, network construction, peptide-TCR binding prediction, generation probability calculation, and k-mer motif analysis for TCR sequences, making TCR data analysis as simple as possible. The TCRosetta server accepts multiple input data formats and can analyze ∼ 20,000 TCR sequences in less than 3 min. TCRosetta is the most comprehensive web server available for TCR repertoire analysis and is freely available at https://guolab.wchscu.cn/TCRosetta/.

Novel Predictive Biomarkers in the Head and Neck Squamous Cell Carcinoma (HNSCC)

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide, characterized by high aggressiveness and frequent metastasis to regional lymph nodes. Despite advances in therapy, including checkpoint inhibitor immunotherapy, surgery, radiotherapy, and chemotherapy, survival rates for patients with advanced HNSCC remain unsatisfactory. This article presents the latest research on predictive biomarkers such as PD-L1, PD-1, CTLA-4, p53, and HPV, which may enhance treatment efficacy and improve clinical outcomes for patients. The clinical value of these biomarkers, their limitations, and their potential application in HNSCC therapy are emphasized. Special attention is given to immunotherapy, which shows promising results in treating this type of cancer through the modulation of the immune response. The review's findings highlight the need for further research on new biomarkers to develop more personalized and effective therapeutic strategies for HNSCC patients.

Precision Medicine and Clinical Trials in Advanced and Metastatic Oral Cancer

Purpose

Oral cancer is a significant global health concern, with high morbidity and mortality rates, particularly in regions with prevalent tobacco usage such as Asia. Majority of oral cancers are detected at an advanced stage resulting in poor survival outcomes. Moreover, the treatment modalities of oral cancers have remained constant with surgery and concurrent chemoradiotherapy being mainstays of the treatment. This review provides a significant progress made in understanding the molecular landscape of oral cancers and the evolution of therapeutic strategies toward precision medicine.

Methods

A comprehensive literature review was conducted to gather recent studies on the molecular landscape of oral cancers, genomic insights, and clinical trials.

Results

Firstly, genomic insights into oral cancers, including key driver mutations and copy number alterations, are discussed in the context of personalized medicine approaches. Subsequently, advancements in therapeutic strategies, particularly focusing on clinical trials investigating immunotherapy and targeted agents, are highlighted.

Conclusion

Despite promising results, challenges persist in identifying reliable biomarkers for treatment response and resistance. Continued research efforts are warranted to validate biomarkers and optimize therapeutic interventions, with the goal of enhancing patient outcomes and reducing the global burden of oral cancer.

Immunotherapy: The Fourth Domain in Oral Cancer Therapeutics

Owing to high global prevalence, incidence and associated mortality, cancer of head and neck particularly oral cancer remains a cardinal domain for research and trials. Immune-modulatory therapies that employ patients own immune system for therapeutic benefits in oral cancer seems promising. The aim of this review is to gauge the potential of immunotherapy as fourth domain of Oral cancer therapeutics. Articles were searched using suitable search terms in MEDLINE and Google Scholar database to include clinical trials, meta-analyses, and research in humans/animals/cell lines published in peer reviewed journals. A total of 97 articles were included in this review. Literature has several studies and trials where different types of immunotherapies has been attempted but it is crucial to identify precise biomarkers of genome based targeted agents and to find parameters to select patients who might benefit from immunotherapy. Also further research is required to estimate predictive value of tumor mutational burden and mutational signatures so as to aid in personalized prediction of oral cancer therapeutic response.

Regulatory T-cells activated in metastatic draining lymph nodes possibly suppress cancer immunity in cancer tissues of head and neck squamous cell cancer

Regulatory T cells (Tregs) play an important role in creating an immunosuppressive microenvironment in cancer tissues. However, the mechanisms by which Tregs are activated and suppress cancer immunity remain unclear. To elucidate these mechanisms, we performed a T cell receptor (TCR) repertoire analysis of Tregs and conventional T cells in peripheral blood, draining lymph nodes (DLNs), and cancer tissues of patients with head and neck squamous cell cancer (HNSCC). We found that the TCR repertoire was skewed in cancer tissue and metastatic DLNs (M-DLNs) compared with non-metastatic DLNs, and TCR repertoire similarities in Tregs and CD8+ T cells between M-DLNs and cancer tissue were high compared with those at other sites. These results suggest that Tregs and CD8+ T cells are activated in M-DLNs and cancer tissues by cancer antigens, such as neoantigens, and shared antigens and Tregs suppress CD8+ T cell function in a cancer antigen-specific manner in M-DLNs and cancer tissue. Moreover, M-DLNs might be a source of Tregs and CD8+ T cells recruited into the cancer tissue. Therefore, targeting Tregs in M-DLNs in an antigen-specific manner is expected to be a novel immunotherapeutic strategy for HNSCCs.

PD-1 inhibitor combined with paclitaxel and cisplatin in the treatment of recurrent and metastatic hypopharyngeal/laryngeal squamous cell carcinoma: efficacy and survival outcomes

Objective

This retrospective study analyzed the efficacy of PD-1 inhibitors combined with albumin-bound paclitaxel and cisplatin (TP regimen) in the treatment of recurrent and metastatic hypopharyngeal/laryngeal squamous cell carcinoma (RMHSCC/RMLSCC).

Methods

Patients diagnosed and treated at the Sun Yat-sen University Cancer Center from August 1, 2020, to August 15, 2023, with histologically confirmed RMHSCC/RMLSCC were included. All patients received PD-1 inhibitors combined with albumin-bound paclitaxel (260mg/m2) and cisplatin (60mg/m2) for 3-4 cycles. The primary endpoints were overall survival (OS) and progression-free survival (PFS).

Results

A total of 50 patients with RMHSCC/RMLSCC who received TP+PD-1 inhibitor therapy were included, with an objective response rate (ORR) of 56.0% (28/50). The 1-year and 2-year OS rates were 80.2% (95% CI: 69.3%-92.9%) and 68.6% (95% CI: 52.6%-89.5%), respectively, while the 1-year and 2-year PFS rates were 44.7% (95% CI: 31.9%-62.5%) and 26.0% (95% CI: 12.6%-53.4%), respectively. Treatment-related adverse events mainly included rash, myelosuppression, gastrointestinal reactions, and hypothyroidism.

Conclusion

In the treatment of RMHSCC/RMLSCC with TP + PD-1 inhibitors, survival rates of patients can be improved while ensuring the safety of the treatment regimen.

Panoramic analysis of cell death patterns reveals prognostic and immune profiles of head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) has been characterized by a low therapeutic response and poor prognosis. Currently, there are no reliable predictive models for HNSCC progression and therapeutic efficacy. This study explores the role of diverse patterns of cell death in tumor development, positing them as predictive factors of HNSCC prognosis. We utilized bulk transcriptome and single-cell transcriptome, align with clinical information from TCGA and GEO database, to analyze genes associated with 15 types of cell death and construct a cell death index (CDI) signature. The associations of CDI with tumor-infiltrating immune cells and immunotherapy-related biomarkers were also evaluated using various algorithms. The CDI signature emerged as a robust prognosis biomarker that could identify patients who can benefit potentially from immunotherapy, thus improving diagnostic accuracy and optimizing clinical decisions in HNSCC management. Notably, we discovered that CAAP1 deficiency not only induced apoptosis but also enhanced anti-tumor immunity, suggesting its potential as a target for clinical drug development.

Tumor immune dysfunction and exclusion subtypes in bladder cancer and pan-cancer: a novel molecular subtyping strategy and immunotherapeutic prediction model

BACKGROUND

Molecular subtyping is expected to enable precise treatment. However, reliable subtyping strategies for clinical application remains defective and controversial. Given the significance of tumor immune dysfunction and exclusion (TIDE), we aimed to develop a novel TIDE-based subtyping strategy to guide personalized immunotherapy in the bladder cancer (BC).

METHODS

Transcriptome data of BC was used to evaluate the heterogeneity and the status of TIDE patterns. Subsequently, consensus clustering was applied to classify BC patients based on TIDE marker-genes. Patients' clinicopathological, molecular features and signaling pathways of the different TIDE subtypes were well characterized. We also utilize the deconvolution algorithms to analyze the tumor microenvironment, and further explore the sensitivity and mechanisms of each subtype to immunotherapy. Furthermore, BC patient clinical information, real-world BC samples and urine samples were collected for the validation of our findings, which were used for RNA-seq analysis, H&E staining, immunohistochemistry and immunofluorescence staining, and enzyme-linked immunosorbent assay. Finally, we also explored the conservation of our novel TIDE subtypes in pan-cancers.

RESULTS

We identified 69 TIDE biomarker genes and classified BC samples into three subtypes using consensus clustering. Subtype I showed the lowest TIDE status and malignancy with the best prognosis and highest sensitivity to immune checkpoint blockade (ICB) treatment, which was enriched of metabolic related signaling pathways. Subtype III represented the highest TIDE status and malignancy with the poorest prognosis and resistance to ICB treatment, resulting from its inhibitory immune microenvironment and T cell terminal exhaustion. Subtype II was in a transitional state with intermediate TIDE level, malignancy, and prognosis. We further confirmed the existence and characteristics of our novel TIDE subtypes using real-world BC samples and collected patient clinical data. This subtyping method was proved to be more efficient than previous known methods in identifying non-responders to immunotherapy. We also propose that combining our TIDE subtypes with known biomarkers can potentially improve the sensitivity and specificity of these biomarkers. Moreover, besides guiding ICB treatment, this classification approach can assist in selecting the frontline or recommended drugs. Finally, we confirmed that the TIDE subtypes are conserved across the pan-tumors.

CONCLUSIONS

Our novel TIDE-based subtyping method can serve as a powerful clinical tool for BC and pan-cancer patients, and potentially guiding personalized therapy decisions for selecting potential beneficiaries and excluding resistant patients of ICB therapy.

Mass cytometry and transcriptomic profiling reveal PD1 blockade induced alterations in oral carcinogenesis

Oral squamous cell carcinoma is the predominant subtype of head and neck squamous cell carcinoma, characterized by a challenging prognosis. In this study, we established a murine model of oral carcinogenesis using 4-nitroquinoline-1-oxide (4-NQO) induction to investigate the impact of immunotherapy on microenvironmental alterations. Mice in the precancerous condition were randomly divided into two groups: one receiving programmed death-1 (PD1) monoclonal antibody treatment and the other, control immunoglobulin G. Our observations showed that while PD1 blockade effectively delayed the progression of carcinogenesis, it did not completely impede or reverse it. To unravel the underlying reasons for the limited effectiveness of PD1 blockade, we collected tongue lesions and applied mass cytometry (CyTOF) and RNA sequencing (RNA-seq) to characterize the microenvironment. CyTOF analysis revealed an increased macrophage subset (expressing high levels of IFNγ and iNOS) alongside a diminished Th1-like subset (exhibiting low expression of TCF7) and three myeloid-derived suppressor cell subsets (displaying low expression of MHC Class II or IFNγ) following anti-PD1 treatment. Notably, we observed an increased presence of cancer-associated fibroblasts (CAFs) expressing collagen-related genes after PD1 blockade. Furthermore, we found a negative correlation between the infiltration levels of CAFs and CD8+ T cells. These findings were validated in murine tongue tissue slides, and publicly available multi-omics datasets. Our results suggest that CAFs may impair the therapeutic efficacy of PD1 blockade in oral carcinogenesis by the remodeling of the extracellular matrix.

Immune checkpoint CD161/LLT1-associated immunological landscape and diagnostic value in oral squamous cell carcinoma

An active host adaptive response is characterized by the existence of programmed cell death protein 1 (PD-1)+ /IFN-γ+ cytotoxic T cells and IFN-γ-induced PD-L1+ tumor cells (TCs), which predicts high response rate to anti-PD-1/L1 therapy. Recently, CD161 and its ligand LLT1 (CLEC2D) have been identified as an emerging checkpoint for immunotherapy. Clarifying its heterogeneous clinical expression pattern and its immune landscape is a prerequisite for maximizing the response rate of CD161 blockade therapy in a specific population of oral squamous cell carcinoma (OSCC) patients. Here, we investigated the expression pattern of CD161/LLT1 and its association with major immunocytes (T cells, B cells, NK cells, and macrophages) by multiplex immunofluorescence, immunohistochemistry, and flow cytometry in 109 OSCC tissues and 102 peripheral blood samples. TCs showed higher LLT1 levels than tumor infiltrating lymphocytes (TILs), whereas CD161 was highly expressed in CD8+ T cells at the tumor front, which was decreased in paracancerous tissue. High expression of TC-derived LLT1 (LLT1TC ) conferred poor clinical outcomes, whereas higher CD161+ and LLT1+ TILs were associated with better prognosis. Meanwhile, patients with high LLT1TC showed a decreased ratio of CD8+ /Foxp3+ T cells in situ, but CD161+ TILs correlated with more peripheral CD3+ T cells. Interestingly, treatment of OSCC patients with nivolumab (anti-PD-1) could restore tumoral CD161/LLT1 signal. Furthermore, an OSCC subgroup characterized by high LLT1+ TCs and low CD161+ CD8+ T cells showed fewer peripheral T cells and a higher risk of lymph node metastasis, leading to a shorter 5-year survival time (29%). More LLT1TC at the invasive front was another risk characteristic of exhausted T cells. In conclusion, in view of this heterogeneity, the LLT1/CD161 distribution pattern should be determined before CD161-based immunotherapy.

Expression of PD-L1 and p-RPS6 in epithelial dysplasia and squamous cell carcinoma of the oral cavity

Introduction

Oral squamous cell carcinoma (OSCC) is often preceded by oral epithelial dysplasia (OED). The role of ribosomal protein S6 (RPS6) and programmed cell death ligand-1 (PD-L1) in the progression of OED to OSCC remains unclear. This study aimed to investigate the expression of phosphorylated RPS6 (p-RPS6) and PD-L1 in OSCC and OED and to examine its relationship with clinicopathological features.

Methods

Fifty-two OSCC and 48 OED cases were recruited for immunohistochemical analysis of p-RPS6 and PD-L1 expression. The expression of markers was correlated with clinicopathological features of OSCC and OED.

Results

We found p-RPS6 expression in all cases of OSCC and OED, whereas PD-L1 was expressed in 42/48 (87%) OED and in 28/52 (53%) OSCC. The patients with mild OED presented higher expression level of PD-L1 and p-RPS6 significantly, when compared to moderate-differentiated OSCC patients (p < 0.05). Moreover, we found a significant positive correlation between PD-L1 and p-RPS6 expression in OED and OSCC patients (p < 0.01). The PD-L1 expression was significantly related to more than 2 cm tumor size in OSCC patients (p = 0.007).

Discussion

Our findings suggest the upregulation of PD-L1 may be related with activation of the mTOR pathway in the early events of tumor progression and the pathogenesis of OSCC.

TCCIA: a comprehensive resource for exploring CircRNA in cancer immunotherapy

BACKGROUND

Immunotherapies targeting immune checkpoints have gained increasing attention in cancer treatment, emphasizing the need for predictive biomarkers. Circular RNAs (circRNAs) have emerged as critical regulators of tumor immunity, particularly in the PD-1/PD-L1 pathway, and have shown potential in predicting immunotherapy efficacy. Yet, the detailed roles of circRNAs in cancer immunotherapy are not fully understood. While existing databases focus on either circRNA profiles or immunotherapy cohorts, there is currently no platform that enables the exploration of the intricate interplay between circRNAs and anti-tumor immunotherapy. A comprehensive resource combining circRNA profiles, immunotherapy responses, and clinical outcomes is essential to advance our understanding of circRNA-mediated tumor-immune interactions and to develop effective biomarkers.

METHODS

To address these gaps, we constructed The Cancer CircRNA Immunome Atlas (TCCIA), the first database that combines circRNA profiles, immunotherapy response data, and clinical outcomes across multicancer types. The construction of TCCIA involved applying standardized preprocessing to the raw sequencing FASTQ files, characterizing circRNA profiles using an ensemble approach based on four established circRNA detection tools, analyzing tumor immunophenotypes, and compiling immunotherapy response data from diverse cohorts treated with immune checkpoint blockades (ICBs).

RESULTS

TCCIA encompasses over 4,000 clinical samples obtained from 25 cohorts treated with ICBs along with other treatment modalities. The database provides researchers and clinicians with a cloud-based platform that enables interactive exploration of circRNA data in the context of ICB. The platform offers a range of analytical tools, including browse of identified circRNAs, visualization of circRNA abundance and correlation, association analysis between circRNAs and clinical variables, assessment of the tumor immune microenvironment, exploration of tumor molecular signatures, evaluation of treatment response or prognosis, and identification of altered circRNAs in immunotherapy-sensitive and resistant tumors. To illustrate the utility of TCCIA, we showcase two examples, including circTMTC3 and circMGA, by employing analysis of large-scale melanoma and bladder cancer cohorts, which unveil distinct impacts and clinical implications of different circRNA expression in cancer immunotherapy.

CONCLUSIONS

TCCIA represents a significant advancement over existing resources, providing a comprehensive platform to investigate the role of circRNAs in immuno-oncology.

Personalised Medicine and the Potential Role of Electrospinning for Targeted Immunotherapeutics in Head and Neck Cancer

Advanced head and neck cancer (HNC) is functionally and aesthetically destructive, and despite significant advances in therapy, overall survival is poor, financial toxicity is high, and treatment commonly exacerbates tissue damage. Although response and durability concerns remain, antibody-based immunotherapies have heralded a paradigm shift in systemic treatment. To overcome limitations associated with antibody-based immunotherapies, exploration into de novo and repurposed small molecule immunotherapies is expanding at a rapid rate. Small molecule immunotherapies also have the capacity for chelation to biodegradable, bioadherent, electrospun scaffolds. This article focuses on the novel concept of targeted, sustained release immunotherapies and their potential to improve outcomes in poorly accessible and risk for positive margin HNC cases.

Integrative multi-omics analysis unveils stemness-associated molecular subtypes in prostate cancer and pan-cancer: prognostic and therapeutic significance

BACKGROUND

Prostate cancer (PCA) is the fifth leading cause of cancer-related deaths worldwide, with limited treatment options in the advanced stages. The immunosuppressive tumor microenvironment (TME) of PCA results in lower sensitivity to immunotherapy. Although molecular subtyping is expected to offer important clues for precision treatment of PCA, there is currently a shortage of dependable and effective molecular typing methods available for clinical practice. Therefore, we aim to propose a novel stemness-based classification approach to guide personalized clinical treatments, including immunotherapy.

METHODS

An integrative multi-omics analysis of PCA was performed to evaluate stemness-level heterogeneities. Unsupervised hierarchical clustering was used to classify PCAs based on stemness signature genes. To make stemness-based patient classification more clinically applicable, a stemness subtype predictor was jointly developed by using four PCA datasets and 76 machine learning algorithms.

RESULTS

We identified stemness signatures of PCA comprising 18 signaling pathways, by which we classified PCA samples into three stemness subtypes via unsupervised hierarchical clustering: low stemness (LS), medium stemness (MS), and high stemness (HS) subtypes. HS patients are sensitive to androgen deprivation therapy, taxanes, and immunotherapy and have the highest stemness, malignancy, tumor mutation load (TMB) levels, worst prognosis, and immunosuppression. LS patients are sensitive to platinum-based chemotherapy but resistant to immunotherapy and have the lowest stemness, malignancy, and TMB levels, best prognosis, and the highest immune infiltration. MS patients represent an intermediate status of stemness, malignancy, and TMB levels with a moderate prognosis. We further demonstrated that these three stemness subtypes are conserved across pan-tumor. Additionally, the 9-gene stemness subtype predictor we developed has a comparable capability to 18 signaling pathways to make tumor diagnosis and to predict tumor recurrence, metastasis, progression, prognosis, and efficacy of different treatments.

CONCLUSIONS

The three stemness subtypes we identified have the potential to be a powerful tool for clinical tumor molecular classification in PCA and pan-cancer, and to guide the selection of immunotherapy or other sensitive treatments for tumor patients.

Next-generation sequencing identifies CDKN2A alterations as prognostic biomarkers in recurrent or metastatic head and neck squamous cell carcinoma predominantly receiving immune checkpoint inhibitors

Background

This study aimed to identify potential biomarkers in patients with recurrent or metastatic head and neck squamous cell carcinoma (HNSCC) and further probe the prognostic implications of CDKN2A mutations, particularly within a subset receiving immunotherapy.

Methods

In this retrospective single-center study, we evaluated the next-generation sequencing (NGS) data from Foundation Medicine (FM) for patients with recurrent or metastatic HNSCC between January 1, 2019, and December 31, 2021. Patients were stratified based on CDKN2A loss-of-function (LOF) versus wild-type (WT) categorizations, with a focused subgroup analysis on those administered immunotherapy.

Results

The study encompassed 77 patients, of which 62 had undergone immunotherapy. The median duration of follow-up was 22.6 months. For the CDKN2A LOF group, the median overall survival (OS) was 16.5 months, contrasted with 30.0 months in the CDKN2A WT group (P=0.014). Notably, female gender (hazard ratio [HR]=4.526, 95% confidence interval [CI]: 1.934-10.180, P=0.0003) and CDKN2A LOF (HR=2.311, 95% CI: 1.156-4.748, P=0.019) emerged as independent risk factors for mortality in patients with recurrent or metastatic HNSCC. Within the immunotherapy subset, the median OS was 11.7 months for the CDKN2A LOF group, and 22.5 months for the CDKN2A WT group (P=0.017). Further, the female gender (HR=4.022, 95% CI: 1.417-10.710, P=0.006), CDKN2A LOF (HR=4.389, 95% CI: 1.782-11.460, P=0.002), and a combined positive score below 1 (HR=17.20, 95% CI: 4.134-79.550, P<0.0001) were identified as significant predictors of mortality among patients with recurrent or metastatic HNSCC receiving immunotherapy.

Conclusion

Alterations manifesting as LOF in the CDKN2A gene stand as robust indicators of unfavorable survival outcomes in HNSCC patients, including the subset that underwent immunotherapy.

Nivolumab for Recurrent or Metastatic Head and Neck Squamous Cell Carcinoma: A Retrospective Tertiary Centre's Real-World Experience

Nivolumab, a PD-1 checkpoint inhibitor, was approved in Canada in 2017 for the treatment of recurrent or metastatic head and neck squamous cell carcinoma (R/M HNSCC) based on the phase 3 trial CHECKMATE-141. We aimed to examine the demographics and efficacy of nivolumab in a Canadian, real-world setting. A retrospective chart review was performed on patients who received nivolumab for R/M HNSCC from 2017 to 2020 at a high-volume cancer centre. Data were abstracted from 34 patients, based on physician notes and imaging reports. The median patient age at nivolumab initiation was 61, 24% were female, and 62% were current or former smokers. Prior to nivolumab, 44% of patients underwent surgery, 97% radiation, and 100% chemotherapy. Most (97%) therapies were for primary disease. Overall survival at 6 and 12 months following drug initiation was 38% and 23%, respectively. Progression-free survival at 6 and 12 months was 33% and 22%, respectively. Eighteen percent of patients experienced an immune-related adverse event, the most common of which was pneumonitis (3/8) and endocrine events (3/8). Seven out of eight of the immune adverse events were grade 1-2; 1/8 was grade 3. Nivolumab appears to have decreased survival rates in our single-centre Canadian population compared to CHECKMATE-141 and presented a manageable adverse event profile for R/M HNSCC.

Identification of TCR repertoire patterns linked with anti-cancer immunotherapy

The highly diverse T cell receptor (TCR) repertoire is a crucial component of the adaptive immune system that aids in the protection against a wide variety of pathogens. This TCR repertoire, comprising the collection of all TCRs in an individual, is a valuable source of information on both recent and ongoing T cell activation. Cancer cells, like pathogens, have the ability to trigger an adaptive immune response. However, because cancer cells use a variety of strategies to escape immune responses, this is often insufficient to completely eradicate them. As a result, immunotherapy is a promising treatment option for cancer patients. This treatment is expected to increase T cell activation and subsequently alter the TCR repertoire composition in these patients. Monitoring TCR repertoires before and after immunotherapy can therefore provide additional insight into T cell responses and might identify cancer-associated TCR sequences. Here we present a computational strategy to identify those changes in the TCR repertoire that occur after treatment with immunotherapy. Since this method allows the identification of TCR patterns that might be treatment-associated, it can help future research by revealing those patterns that are related with response. This TCR analysis workflow is illustrated using public data from three different cancer patients who received anti-PD-1 treatment.

Preexisting tumor-resident T cells with cytotoxic potential associate with response to neoadjuvant anti-PD-1 in head and neck cancer

About 50% of patients with locally advanced head and neck squamous cell carcinoma (HNSCC) experience recurrences after definitive therapy. The presurgical administration of anti-programmed cell death protein 1 (PD-1) immunotherapy results in substantial pathologic tumor responses (pTR) within the tumor microenvironment (TME). However, the mechanisms underlying the dynamics of antitumor T cells upon neoadjuvant PD-1 blockade remain unresolved, and approaches to increase pathologic responses are lacking. In a phase 2 trial (NCT02296684), we observed that 45% of patients treated with two doses of neoadjuvant pembrolizumab experienced marked pTRs (≥50%). Single-cell analysis of 17,158 CD8+ T cells from 14 tumor biopsies, including 6 matched pre-post neoadjuvant treatment, revealed that responding tumors had clonally expanded putative tumor-specific exhausted CD8+ tumor-infiltrating lymphocytes (TILs) with a tissue-resident memory program, characterized by high cytotoxic potential (CTX+) and ZNF683 expression, within the baseline TME. Pathologic responses after 5 weeks of PD-1 blockade were consistent with activation of preexisting CTX+ZNF683+CD8+ TILs, paralleling loss of viable tumor and associated tumor antigens. Response was associated with high numbers of CD103+PD-1+CD8+ T cells infiltrating pretreatment lesions, whereas revival of nonexhausted persisting clones and clonal replacement were modest. By contrast, nonresponder baseline TME exhibited a relative absence of ZNF683+CTX+ TILs and subsequent accumulation of highly exhausted clones. In HNSCC, revival of preexisting ZNF683+CTX+ TILs is a major mechanism of response in the immediate postneoadjuvant setting.

Targeting oral tumor microenvironment for effective therapy

Oral cancers are among the common head and neck malignancies. Different anticancer therapy modalities such as chemotherapy, immunotherapy, radiation therapy, and also targeted molecular therapy may be prescribed for targeting oral malignancies. Traditionally, it has been assumed that targeting malignant cells alone by anticancer modalities such as chemotherapy and radiotherapy suppresses tumor growth. In the last decade, a large number of experiments have confirmed the pivotal role of other cells and secreted molecules in the tumor microenvironment (TME) on tumor progression. Extracellular matrix and immunosuppressive cells such as tumor-associated macrophages, myeloid-derived suppressor cells (MDSCs), cancer-associated fibroblasts (CAFs), and regulatory T cells (Tregs) play key roles in the progression of tumors like oral cancers and resistance to therapy. On the other hand, infiltrated CD4 + and CD8 + T lymphocytes, and natural killer (NK) cells are key anti-tumor cells that suppress the proliferation of malignant cells. Modulation of extracellular matrix and immunosuppressive cells, and also stimulation of anticancer immunity have been suggested to treat oral malignancies more effectively. Furthermore, the administration of some adjuvants or combination therapy modalities may suppress oral malignancies more effectively. In this review, we discuss various interactions between oral cancer cells and TME. Furthermore, we also review the basic mechanisms within oral TME that may cause resistance to therapy. Potential targets and approaches for overcoming the resistance of oral cancers to various anticancer modalities will also be reviewed. The findings for targeting cells and potential therapeutic targets in clinical studies will also be reviewed.

Multi-organ landscape of therapy-resistant melanoma

Metastasis and failure of present-day therapies represent the most common causes of mortality in patients with cutaneous melanoma. To identify the underlying genetic and transcriptomic landscapes, in this study we analyzed multi-organ metastases and tumor-adjacent tissues from 11 rapid autopsies after treatment with MAPK inhibitor (MAPKi) and/or immune checkpoint blockade (ICB) and death due to acquired resistance. Either treatment elicits shared genetic alterations that suggest immune-evasive, cross-therapy resistance mechanisms. Large, non-clustered deletions, inversions and inter-chromosomal translocations dominate rearrangements. Analyzing data from separate melanoma cohorts including 345 therapy-naive patients and 35 patients with patient-matched pre-treatment and post-acquired resistance tumor samples, we performed cross-cohort analyses to identify MAPKi and ICB as respective contributors to gene amplifications and deletions enriched in autopsy versus therapy-naive tumors. In the autopsy cohort, private/late mutations and structural variants display shifted mutational and rearrangement signatures, with MAPKi specifically selecting for signatures of defective homologous-recombination, mismatch and base-excision repair. Transcriptomic signatures and crosstalks with tumor-adjacent macroenvironments nominated organ-specific adaptive pathways. An immune-desert, CD8+-macrophage-biased archetype, T-cell exhaustion and type-2 immunity characterized the immune contexture. This multi-organ analysis of therapy-resistant melanoma presents preliminary insights with potential to improve therapeutic strategies.

IL-33/ST2 signaling promotes constitutive and inductive PD-L1 expression and immune escape in oral squamous cell carcinoma

BACKGROUND

Loss-of-function of PD-L1 induces therapy resistance of anti-PD-1/L1 therapy, and the complex regulatory mechanisms are not completely understood. We previously reported that stroma-derived interleukin-33 (IL-33) promoted the progression of oral squamous cell carcinoma (OSCC). We here focused on the immune-regulation role of IL-33 and its receptor ST2 signaling in PD-L1-positive OSCC patients.

METHODS

Activated T cells in in situ and peripheral blood were analyzed by IL-33/ST3 expression. Knockdown or overexpression of ST2 combined with IL-33/IFN-γ stimulation were performed to determine PD-L1 expression and PD-L1-dependent immune escape in OSCC/human T cells co-culture system, and OSCC orthotopic model based on humanized mouse with immune reconstitution and C57BL/6 mice models.

RESULTS

High IL-33/ST2 correlated with less activated T cells infiltration in situ and peripheral blood. Knockdown of ST2 down-regulated constitutive PD-L1 expression, whereas ST2 also promoted IL-33-induced PD-L1 Mechanistically, IL-33/ST2 activated JAK2/STAT3 pathway to directly promoted PD-L1 expression, and also activated MyD88/NF-κB signaling to up-regulate IFN-γ receptor (IFN-γR), which indirectly strengthen IFN-γ-induced PD-L1. Furthermore, ST2 is required for PD-L1-mediated immune tolerance in vitro and in vivo. ST2high OSCC patients have more PD-L1 and IFN-γR level in situ.

CONCLUSIONS

IL-33/ST2 signaling enhanced PD-L1-mediated immune escape, ST2high OSCC patients might benefit from anti-PD-1/L1 therapy.

Perspectives in Immunotherapy: meeting report from the Immunotherapy Bridge, December 1st-2nd, 2021

Over the past decade, immunotherapy has become an increasingly fundamental modality in the treatment of cancer. The positive impact of immune checkpoint inhibition, especially anti-programmed death (PD)-1/PD-ligand (L)1 blockade, in patients with different cancers has focused attention on the potential for other immunotherapeutic approaches. These include inhibitors of additional immune checkpoints, adoptive cell transfer (ACT), and therapeutic vaccines. Patients with advanced cancers who previously had limited treatment options available may now benefit from immunotherapies that can offer durable responses and improved survival outcomes. However, despite this, a significant proportion of patients fail to respond to immunotherapy, especially those with less immunoresponsive cancer types, and there remains a need for new treatment strategies.The virtual Immunotherapy Bridge (December 1st-2nd, 2021), organized by the Fondazione Melanoma Onlus, Naples, Italy in collaboration with the Society for Immunotherapy of Cancer addressed several areas of current research in immunotherapy, including lessons learned from cell therapies, drivers of immune response, and trends in immunotherapy across different cancers, and these are summarised here.

Preoperative immunotherapy for head and neck cancers: state of art

PURPOSE OF REVIEW

Programmed cell death 1 (PD-l)-targeting agents have been FDA-approved for treatment of recurrent/ metastatic head and neck squamous cell carcinoma (HNSCC). Clinical studies employing these agents preoperatively for HNSCC in the definitive setting are emerging and have important implications.

RECENT FINDINGS

Preclinical studies demonstrate enhanced effectiveness of preoperative PD-1 targeting compared with postoperative treatment. Nine HNSCC clinical studies evaluating preoperative treatment with PD-1-targeted pembrolizumab/nivolumab alone or in combination therapy were recently reported. These studies differed by preoperative treatment type and duration and reported no surgical delays, no unexpected surgical complications and grade 3-4 immune-related adverse events consistent with the employed immunotherapeutic agent(s). Rates of major pathologic response (MPR), reduced residual viable tumour to 10% or less, ranged from 2.9-31% across eight trials without neoadjuvant radiation therapy. Higher PD-1 ligand (PD-L1) expression, increased inflammatory gene expression and enhanced immune cell tumour infiltration in baseline biopsies were associated with pathologic tumour response (pTR) in some studies. Any degree of pTR was associated with improved survival/relapse outcomes in two studies.

SUMMARY

Emerging preoperative anti-PD-1 HNSCC clinical studies indicate that preoperative treatment does not impact surgical management. Defining predictive biomarkersand tumour pathologic response implications for patient survival are areas for further investigation.