LAG-3 confers poor prognosis and its blockade reshapes antitumor response in head and neck squamous cell carcinoma

Immunotherapy for head and neck cancer: Fundamentals and therapeutic development

Squamous cell carcinoma of the head and neck (SCCHN) has been treated by multidisciplinary therapy consisting of surgery, radiotherapy, and cancer chemotherapy, but the recent advent of immunotherapy has produced significant changes in treatment systems and the results of these therapies. Immunotherapy has greatly improved the outcome of recurrent metastatic SCCHN, and the development of new treatment methods based on immunotherapy is now being applied not only to recurrent metastatic cases but also to locally advanced cases. To understand and practice cancer immunotherapy, it is important to understand the immune environment surrounding cancer, and the changes to which it is subject. Currently, the anti-PD-1 antibody drugs nivolumab and pembrolizumab are the only immunotherapies with proven efficacy in head and neck cancer. However, anti-PD-L1 and anti-CTLA-4 antibody drugs have also been shown to be useful in other types of cancer and are being incorporated into clinical practice. In head and neck cancer, numerous clinical trials have aimed to improve efficacy and safety by combining immunotherapy with other drug therapies and treatment modalities. Combinations of immunotherapy with cancer drugs with different mechanisms of action (cytotoxic agents, molecular-targeted agents, immune checkpoint inhibitors), as well as with radiation therapy and surgery are being investigated, and have the potential to significantly change medical care for these patients. The application of cancer immunotherapy not only to daily clinical practice but also to further therapeutic development requires a clear and complete understanding of the fundamentals of cancer immunotherapy, and knowledge of the numerous clinical studies conducted, both past and present. The results of these trials are numerous, both positive and negative, and a comprehensive understanding of this wide range of completed and ongoing clinical trials is critical to a systematic and comprehensive understanding of their scope and lessons learnt. In this article, after outlining the concepts of ``cancer immune cycle,'' ``cancer immune editing,'' and ``tumor microenvironment'' to provide an understanding of the basics of cancer immunity, we summarize the basics and clinical trial data on representative immune checkpoint inhibitors used in various cancer types, as well as recent therapeutic developments in cancer immunotherapy and the current status of these new treatments.

Molecular characterization of the evolution of premalignant lesions in the upper aerodigestive tract

Introduction

Early relapse and development of metastatic disease are some of the primary reasons for the poor prognosis of patients with head and neck squamous cell carcinoma (HNSCC). HNSCC is a heterogeneous disease which may develop in large premalignant fields of genetically altered cells. Yet knowing which individuals will progress and develop clinically significant cancers during their lifetimes remains one of the most important challenges of reducing HNSCC morbidity and mortality. To further elucidate the molecular mechanisms, we performed a focused analysis of the genome and immune microenvironment from multiple, matched normal squamous tissue, premalignant lesions, as well as primary and recurrent tumors from seven patients with p16-negative HNSCC.

Methods

We performed targeted panel Next Generation Sequencing (161 genes) to analyze somatic variants from sequentially collected, matched formalin-fixed paraffin-embedded tissue (normal, premalignant, HNSCC) from two patients. These samples plus samples from five additional patients were analyzed with the Nanostring PanCancer Immune Panel. In addition, we performed shallow whole genome sequencing (0.5x coverage on average) on samples from three of these patients. Patients were, apart from one case, primarily treated with curative-intent surgery, and received subsequent adjuvant treatment, if indicated.

Results

The most frequently mutated genes were TP53 and NOTCH1. Other mutated genes included NOTCH3 and CDKN2A, among others. A significant number of mutations were private to dysplasia and invasive carcinoma, respectively, however, almost 20% were shared between them. Increasing genomic instability was observed when comparing histologically normal squamous mucosa with higher levels of dysplasia. High-grade dysplasia showed similarly rearranged genomes as invasive carcinoma. Pathways related to interferon alpha and gamma response were upregulated even in moderate dysplastic lesions with increasing expression in higher grades of dysplasia and carcinoma. SPINK5, a known tumor suppressor gene in HNSCC, was already downregulated in low-grade dysplastic lesions, indicating an early deactivation in the evolution of the disease.

Conclusion

Genomic alterations as well as aberrant immune gene expression can be observed early in the evolution of tumors of the upper aerodigestive tract, highlighting the potential for targeting early mechanisms of disease progression.

Immuno-Oncology: New Insights into Targets and Therapies

The role of immunotherapy in the care of surgical oncology patients promises to expand as investigators and clinicians evaluate new targets and approaches. Currently active clinical trials evaluate new immune checkpoints, including lymphocyte activation gene 3, T cell immunoreceptor with Ig and ITIM domains, and killer Ig-like receptor 2DL1/2L3. Vaccines delivered through mRNA have demonstrated exciting results in early clinical trials and hold promise for expanded application. Investigational approaches include dendritic cell vaccines, peptide vaccines, cytokines therapies, and cellular therapies. These studies have the potential to revolutionize the management of surgical oncology patients and promote durable cures following surgical resection.

The Use of Immune Regulation in Treating Head and Neck Squamous Cell Carcinoma (HNSCC)

Immunotherapy has emerged as a promising new treatment modality for head and neck cancer, offering the potential for targeted and effective cancer management. Squamous cell carcinomas pose significant challenges due to their aggressive nature and limited treatment options. Conventional therapies such as surgery, radiation, and chemotherapy often have limited success rates and can have significant side effects. Immunotherapy harnesses the power of the immune system to recognize and eliminate cancer cells, and thus represents a novel approach with the potential to improve patient outcomes. In the management of head and neck squamous cell carcinoma (HNSCC), important contributions are made by immunotherapies, including adaptive cell therapy (ACT) and immune checkpoint inhibitor therapy. In this review, we are focusing on the latter. Immune checkpoint inhibitors target proteins such as programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) to enhance the immune response against cancer cells. The CTLA-4 inhibitors, such as ipilimumab and tremelimumab, have been approved for early-stage clinical trials and have shown promising outcomes in terms of tumor regression and durable responses in patients with advanced HNSCC. Thus, immune checkpoint inhibitor therapy holds promise in overcoming the limitations of conventional therapies. However, further research is needed to optimize treatment regimens, identify predictive biomarkers, and overcome potential resistance mechanisms. With ongoing advancements in immunotherapy, the future holds great potential for transforming the landscape of oral tumor treatment and providing new hope for patients.

The dynamic role of immune checkpoint molecules in diagnosis, prognosis, and treatment of head and neck cancers

Head and neck cancer (HNC) is the sixth most common cancer type, accounting for approximately 277,597 deaths worldwide. Recently, the Food and Drug Administration (FDA) has approved immune checkpoint blockade (ICB) agents targeting programmed death-1 (PD-1) and programmed death-ligand 1 (PD-L1) as a treatment regimen for head and neck squamous cell carcinomas (HNSCC). Studies have reported the role of immune checkpoint inhibitors as targeted therapeutic regimens that unleash the immune response against HNSCC tumors. However, the overall response rates to immunotherapy vary between 14-32% in recurrent or metastatic HNSCC, with clinical response and treatment success being unpredictable. Keeping this perspective in mind, it is imperative to understand the role of T cells, natural killer cells, and antigen-presenting cells in modulating the immune response to immunotherapy. In lieu of this, these immune molecules could serve as prognostic and predictive biomarkers to facilitate longitudinal monitoring and understanding of treatment dynamics. These immune biomarkers could pave the path for personalized monitoring and management of HNSCC. In this review, we aim to provide updated immunological insight on the mechanism of action, expression, and the clinical application of immune cells' stimulatory and inhibitory molecules as prognostic and predictive biomarkers in HNC. The review is focused mainly on CD27 and CD137 (members of the TNF-receptor superfamily), natural killer group 2 member D (NKG2D), tumor necrosis factor receptor superfamily member 4 (TNFRSF4 or OX40), S100 proteins, PD-1, PD-L1, PD-L2, T cell immunoglobulin and mucin domain 3 (TIM-3), cytotoxic T lymphocyte-associated antigen 4 (CTLA-4), lymphocyte-activation gene 3 (LAG-3), indoleamine-pyrrole 2,3-dioxygenase (IDO), B and T lymphocyte attenuator (BTLA). It also highlights the importance of T, natural killer, and antigen-presenting cells as robust biomarker tools for understanding immune checkpoint inhibitor-based treatment dynamics. Though a comprehensive review, all aspects of the immune molecules could not be covered as they were beyond the scope of the review; Further review articles can cover other aspects to bridge the knowledge gap.

Lymphocyte-activation gene 3 (LAG-3) as a promising immune checkpoint in cancer immunotherapy: From biology to the clinic

In recent years, there have been notable advancements in the field of cancer immunotherapy, namely in the area of immune checkpoint inhibition. The Lymphocyte-activation gene 3 (LAG-3) has garnered attention as a potentially valuable focus of study in this particular field. The present study examines the biological aspects of LAG-3, its clinical consequences, and the potential therapeutic opportunities associated with its modulation. LAG-3, similar to CD4, has a regulatory role in modulating the immune system. The upregulation of this protein inside the neoplastic milieu hampers the immune system's ability to mount an effective response, hence enabling the evasion of cancer cells from immune surveillance. The LAG-3 protein interacts with ligands, inhibiting cytotoxic immune cells such as CD8+ T cells and NK cells. The potential of LAG-3 inhibitors presents intriguing prospects. Integrating these medicines with established treatments like PD-1/PD-L1 or CTLA-4 inhibitors can broaden the range of available therapy choices and address resistance issues. The advent of personalized therapy is imminent, as evidenced by the utilization of predictive biomarkers such as LAG-3 expression to inform individualized therapeutic approaches. Additionally, inhibitors of LAG-3 exhibit promise in addressing immunological depletion and resistance by revitalizing T cells and producing durable immune responses. The realization of LAG-3's promise necessitates global collaboration and equal access. Multinational trials are expected to ascertain the efficacy of the intervention in various patient groups.

Uncovering immune checkpoint heterogeneity in oral squamous cell carcinoma using single cell RNA-sequencing data highlights three subgroups of patients with distinct immune phenotypes

OBJECTIVES

In head and neck squamous cell carcinoma (HNSCC), PD-1/PD-L1 inhibitors remain inefficient in most patients, which points to the need for better characterization of immune checkpoint (ICP) molecule expression.

MATERIAL AND METHODS

We evaluated the expression of 22 ICP ligands (ICPL) in 2,176 malignant cells from 10 patients in a public single-cell RNA-sequencing dataset and in two cohorts of HNSCC patients for which gene expression data are available.

RESULTS

Based on ICPL expression, malignant cells formed three distinct clusters characterized either by a strong expression of ICPL together with an immune phenotype linked to IFN-γ response (cluster 1) or by a weak ICPL expression and little response to IFN-γ (clusters 2 and 3). Malignant cells from cluster 3 showed a high PD-L1 expression associated with NRF2 signature. The relevance of 3 groups of patients, i.e "high ICPL/high IFN-γ", "low ICPL/low IFN-γ" or "low ICPL/low IFN-γ/high PD-L1" was confirmed in a cohort of 259 OSCC whole tumor samples from TCGA and in the CLB-IHN cohort including patients treated with PD1/PD-L1 inhibitors. The heterogeneous expression of ICPL among patients' malignant cells was associated with immunologically distinct microenvironments, evaluated with the "hot/cold" and the Tumor microenvironment (TME) classification. Finally, the "low ICPL/low IFN-γ/high PD-L1" group 3 displayed a poor prognosis in the TCGA cohort.

CONCLUSION

Hence, the global picture of ICPL gene expression in malignant cells from HNSCC patients may contribute to the broader issue of improving immunotherapy strategies though a better stratification of patients and the design of new treatment combinations.

Prognostic significance of Lymphocyte-activation gene 3 (LAG3) in patients with solid tumors: a systematic review, meta-analysis and pan-cancer analysis

BACKGROUND

Lymphocyte-activation gene 3 (LAG3) is a recently discovered immune checkpoint molecule that has been linked to immunosuppression and the advancement of cancer in different types of solid tumors. This study aimed to evaluate the prognostic importance of LAG3 and its role in the immune system within solid tumors.

METHODS

Extensive literature searches were conducted using the Pubmed, EMBASE, and Cochrane Library databases to identify relevant studies exploring the effect of LAG3 on survival outcomes. Pooled hazard ratios (HRs) with its 95% confidence intervals (CIs) were calculated to evaluate the prognostic values of LAG3. Afterwards, subgroup analysis and sensitivity analysis were conducted. Pan-cancer analysis investigated the possible relationships between LAG3 expression and genetic alterations, RNA methylation modification-related genes, genomic instability, immune checkpoint genes, and infiltration of immune cells.

RESULTS

A total of 43 studies with 7,118 patients were included in this analysis. Higher expression of LAG3 was associated with worse overall survival (HR = 1.10, 95% CI 1.01-1.19, P = 0.023), but not disease-free survival (HR = 1.41, 95% CI 0.96-2.07, P = 0.078), progression-free survival (HR = 1.12, 95% CI 0.90-1.39, P = 0.317) or recurrence-free survival (HR = 0.98, 95% CI 0.81-1.19, P = 0.871). Subgroup analysis showed that LAG3 might play different prognostic roles in different solid tumors. LAG3 expression was positively associated with immune cell infiltration and immune checkpoint genes in all of the cancers included. LAG3 expression was also found to be associated with microsatellite instability (MSI), copy number variation (CNV), simple nucleoside variation (SNV), tumor mutation burden (TMB), and neoantigen in various types of cancers.

CONCLUSIONS

Elevated expression of LAG3 is linked to poorer prognosis among patients diagnosed with solid cancers. LAG3 might play varying prognostic roles in different types of solid tumors. Given its substantial involvement in cancer immunity and tumorigenesis, LAG3 has garnered attention as a promising prognostic biomarker and a potential target for immunotherapy.

The Novel Checkpoint Target Lymphocyte-Activation Gene 3 Is Highly Expressed in Cutaneous Squamous Cell Carcinoma

BACKGROUND

Lymphocyte activation-gene 3 (LAG-3) is an emerging next-generation immune checkpoint molecule. We aim to define the expression pattern of LAG-3 in cutaneous squamous cell carcinoma (cSCC) as a first step to understand the role of LAG-3 in cSCC prognosis and therapy.

OBJECTIVE

To define the expression pattern of LAG-3 in cSCC as a first step to understand the role of LAG-3 in cSCC prognosis and therapy.

METHODS

To test whether LAG-3 is expressed on cSCC infiltrating lymphocytes, we isolated CD8 + T lymphocytes from three SCC tumors using flow cytometry and performed single-cell RNA sequencing for LAG-3 and programmed cell death protein -1 (PD-1). In addition, we evaluated LAG-3 mRNA expression in formalin-fixed, paraffin-embedded tissue using NanoString technology.

RESULTS

Single-cell RNA sequencing showed that LAG-3 is expressed more than PD-1 in CD8 + tumor infiltrating lymphocytes (50.8% vs 35.2%, respectively). Quantifying LAG-3 mRNA expression showed that compared with normal skin, LAG-3 mRNA is approximately 8 fold higher in immunocompetent associated SCC tumors and approximately 2 fold higher in transplant associated SCC tumors ( p -values <.05). In addition, LAG-3 mRNA was expressed 7.2 fold higher in T2a SCC tumors compared with normal skin ( p -value <.05).

CONCLUSION

Lymphocyte activation-gene 3 is expressed on SCC infiltrating T lymphocytes at a higher percentage than PD-1. In addition, LAG-3 mRNA expression is significantly higher in SCC tumors. Ongoing studies will be performed to define its role as an immune-related biomarker and as a therapeutic target.

Killer instincts: natural killer cells as multifactorial cancer immunotherapy

Natural killer (NK) cells integrate heterogeneous signals for activation and inhibition using germline-encoded receptors. These receptors are stochastically co-expressed, and their concurrent engagement and signaling can adjust the sensitivity of individual cells to putative targets. Against cancers, which mutate and evolve under therapeutic and immunologic pressure, the diversity for recognition provided by NK cells may be key to comprehensive cancer control. NK cells are already being trialled as adoptive cell therapy and targets for immunotherapeutic agents. However, strategies to leverage their naturally occurring diversity and agility have not yet been developed. In this review, we discuss the receptors and signaling pathways through which signals for activation or inhibition are generated in NK cells, focusing on their roles in cancer and potential as targets for immunotherapies. Finally, we consider the impacts of receptor co-expression and the potential to engage multiple pathways of NK cell reactivity to maximize the scope and strength of antitumor activities.

Current Approaches of Immune Checkpoint Therapy in Chronic Lymphocytic Leukemia

OPINION STATEMENT

Increasing understanding of the complex interaction between leukemic and immune cells, which is responsible for tumor progression and immune evasion, has paved the way for the development of novel immunotherapy approaches in chronic lymphocytic leukemia (CLL). One of the well-known immune escape mechanisms of tumor cells is the up-regulation of immune checkpoint molecules. In recent years, targeting immune checkpoint receptors is the most clinically effective immunotherapeutic strategy for cancer treatment. In this regard, various immune checkpoint blockade (ICB) drugs are currently been investigating for their potential effects on improving anti-tumor immune response and clinical efficacy in the hematological malignancies; however, their effectiveness in patients with CLL has shown less remarkable success, and ongoing research is focused on identifying strategies to enhance the efficacy of ICB in CLL.

Targeting LAG-3, TIM-3, and TIGIT for cancer immunotherapy

In one decade, immunotherapy based on immune checkpoint blockades (ICBs) has become a new pillar of cancer treatment following surgery, radiation, chemotherapy, and targeted therapies. However, not all cancer patients benefit from single or combination therapy with anti-CTLA-4 and anti-PD-1/PD-L1 monoclonal antibodies. Thus, an increasing number of immune checkpoint proteins (ICPs) have been screened and their effectiveness evaluated in preclinical and clinical trials. Lymphocyte activation gene-3 (LAG-3), T cell immunoglobulin and mucin-domain-containing-3 (TIM-3), and T cell immunoreceptor with immunoglobulin and tyrosine-based inhibitory motif (ITIM) domain (TIGIT) constitute the second wave of immunotherapy targets that show great promise for use in the treatment of solid tumors and leukemia. To promote the research and clinical application of ICBs directed at these targets, we summarize their discovery, immunotherapy mechanism, preclinical efficiency, and clinical trial results in this review.

LAG-3 as the third checkpoint inhibitor

Lymphocyte activation gene 3 (LAG-3) is an inhibitory receptor that is highly expressed by exhausted T cells. LAG-3 is a promising immunotherapeutic target, with more than 20 LAG-3-targeting therapeutics in clinical trials and a fixed-dose combination of anti-LAG-3 and anti-PD-1 now approved to treat unresectable or metastatic melanoma. Although LAG-3 is widely recognized as a potent inhibitory receptor, important questions regarding its biology and mechanism of action remain. In this Perspective, we focus on gaps in the understanding of LAG-3 biology and discuss the five biggest topics of current debate and focus regarding LAG-3, including its ligands, signaling and mechanism of action, its cell-specific functions, its importance in different disease settings, and the development of novel therapeutics.

LAG-3 Inhibitors: Novel Immune Checkpoint Inhibitors Changing the Landscape of Immunotherapy

One of the most important steps forward in the management of cancer was the discovery of immunotherapy. It has become an essential pillar in the treatment paradigm of cancer patients. Unfortunately, despite the various options presented with immune checkpoint inhibitors (ICIs), the benefit is still limited to select patients and the vast majority of these patients gain either minimal benefit or eventually progress, leaving an unmet need for the development of novel therapeutic agents and strategies. Lymphocyte activation gene-3 (LAG-3), an immune checkpoint receptor protein, is a molecule found on the surface of activated T-cells. It plays a major role in negatively regulating T-cell function thereby providing tumors with an immune escape in the tumor microenvironment (TME). Given its importance in regulating the immune system, LAG-3 has been considered as a promising target in oncology and precision medicine. To date, two LAG-3-directed agents (eftilagimod alpha and relatlimab) have been approved in combination with programmed death-1 (PD-1) inhibitors in the setting of advanced solid tumors. In this review, we discuss the structure of LAG-3, its mechanism of action, and its interaction with its ligands. We also shed light on the emerging treatments targeting LAG-3 for the treatment of solid tumors.

Immunohistochemical scoring of LAG-3 in conjunction with CD8 in the tumor microenvironment predicts response to immunotherapy in hepatocellular carcinoma

Introduction

Immune checkpoint blockade (ICB) is a systemic therapeutic option for advanced hepatocellular carcinoma (HCC). However, low patient response rates necessitate the development of robust predictive biomarkers that identify individuals who will benefit from ICB. A 4-gene inflammatory signature, comprising CD8, PD-L1, LAG-3, and STAT1, was recently shown to be associated with a better overall response to ICB in various cancer types. Here, we examined whether tissue protein expression of CD8, PD-L1, LAG-3, and STAT1 predicts response to ICB in HCC.

Methods

HCC samples from 191 Asian patients, comprising resection specimens from 124 patients (ICB-naïve) and pre-treatment specimens from 67 advanced HCC patients treated with ICB (ICB-treated), were analyzed for CD8, PD-L1, LAG-3, and STAT1 tissue expression using multiplex immunohistochemistry followed by statistical and survival analyses.

Results

Immunohistochemical and survival analyses of ICB-naïve samples showed that high LAG-3 expression was associated with shorter median progression-free survival (mPFS) and overall survival (mOS). Analysis of ICB-treated samples revealed that high proportions of LAG-3⁺ and LAG-3⁺CD8⁺ cells pre-treatment were most closely associated with longer mPFS and mOS. Using a log-likelihood model, adding the total LAG-3⁺ cell proportion to the total CD8⁺ cell proportion significantly increased the predictive values for mPFS and mOS, compared with the total CD8⁺ cell proportion alone. Moreover, levels of CD8 and STAT1, but not PD-L1, were significantly correlated with better responses to ICB. After analyzing viral-related and non-viral HCC samples separately, only the LAG3⁺CD8⁺ cell proportion was significantly associated with responses to ICB regardless of viral status.

Conclusion

Immunohistochemical scoring of pre-treatment levels of LAG-3 and CD8 in the tumor microenvironment may help predict ICB benefits in HCC patients. Furthermore, immunohistochemistry-based techniques offer the advantage of being readily translatable in the clinical setting.

89Zr-immuno-PET using the anti-LAG-3 tracer [89Zr]Zr-BI 754111: demonstrating target specific binding in NSCLC and HNSCC

PURPOSE

Although lymphocyte activation gene-3 (LAG-3) directed therapies demonstrate promising clinical anti-cancer activity, only a subset of patients seems to benefit and predictive biomarkers are lacking. Here, we explored the potential use of the anti-LAG-3 antibody tracer [89Zr]Zr-BI 754111 as a predictive imaging biomarker and investigated its target specific uptake as well as the correlation of its tumor uptake and the tumor immune infiltration.

METHODS

Patients with head and neck (N = 2) or lung cancer (N = 4) were included in an imaging substudy of a phase 1 trial with BI 754091 (anti-PD-1) and BI 754111 (anti-LAG-3). After baseline tumor biopsy and [18F]FDG-PET, patients were given 240 mg of BI 754091, followed 8 days later by administration of [89Zr]Zr-BI 754111 (37 MBq, 4 mg). PET scans were performed 2 h, 96 h, and 144 h post-injection. To investigate target specificity, a second tracer administration was given two weeks later, this time with pre-administration of 40 (N = 3) or 600 mg (N = 3) unlabeled BI 754111, followed by PET scans at 96 h and 144 h post-injection. Tumor immune cell infiltration was assessed by immunohistochemistry and RNA sequencing.

RESULTS

Tracer uptake in tumors was clearly visible at the 4-mg mass dose (tumor-to-plasma ratio 1.63 [IQR 0.37-2.89]) and could be saturated by increasing mass doses (44 mg: 0.67 [IQR 0.50-0.85]; 604 mg: 0.56 [IQR 0.42-0.75]), demonstrating target specificity. Tumor uptake correlated to immune cell-derived RNA signatures.

CONCLUSIONS

[89Zr]Zr-BI-754111 PET imaging shows favorable technical and biological characteristics for developing a potential predictive imaging biomarker for LAG-3-directed therapies.

TRIAL REGISTRATION

ClinicalTrials.gov , NCT03780725. Registered 19 December 2018.

Exploring animal models in oral cancer research and clinical intervention: A critical review

Cancer is a leading cause of death worldwide, but advances in treatment, early detection, and prevention have helped to reduce its impact. To translate cancer research findings into clinical interventions for patients, appropriate animal experimental models, particularly in oral cancer therapy, can be helpful. In vitro experiments using animal or human cells can provide insight into cancer's biochemical pathways. This review discusses the various animal models used in recent years for research and clinical intervention in oral cancer, along with their advantages and disadvantages. We highlight the advantages and limitations of the used animal models in oral cancer research and therapy by searching the terms of animal models, oral cancer, oral cancer therapy, oral cancer research, and animals to find all relevant publications during 2010-2023. Mouse models, widely used in cancer research, can help us understand protein and gene functions in vivo and molecular pathways more deeply. To induce cancer in rodents, xenografts are often used, but companion animals with spontaneous tumours are underutilized for rapid advancement in human and veterinary cancer treatments. Like humans with cancer, companion animals exhibit biological behaviour, treatment responses, and cytotoxic agent responses similar to humans. In companion animal models, disease progression is more rapid, and the animals have a shorter lifespan. Animal models allow researchers to study how immune cells interact with cancer cells and how they can be targeted specifically. Additionally, animal models have been extensively used in research on oral cancers, so researchers can use existing knowledge and tools to better understand oral cancers using animal models.

Lymphocyte-activation gene 3 protein expression in tumor-infiltrating lymphocytes is associated with a poor prognosis of ovarian clear cell carcinoma

BACKGROUND

Histological analysis has revealed the need for new treatment techniques for epithelial ovarian cancer. Immune checkpoint inhibitors may be a new therapeutic strategy for ovarian clear cell carcinoma (OCCC). Lymphocyte-activation gene 3 (LAG-3), an immune checkpoint, is a poor prognostic factor and a new therapeutic target for several malignancies. In this study, we demonstrated the correlation between LAG-3 expression and the clinicopathological features of OCCC. We evaluated LAG-3 expression in tumor-infiltrating lymphocytes (TILs) via immunohistochemical analysis using tissue microarrays containing surgically resected specimens from 171 patients with OCCC.

RESULTS

The number of LAG-3-positive cases was 48 (28.1%), whereas the number of LAG-3-negative cases was 123 (71.9%). LAG-3 expression significantly increased in patients with advanced stages (P = 0.036) and recurrence (P = 0.012); however, its expression did not correlate with age (P = 0.613), residual tumor (P = 0.156), or death (P = 0.086). Using the Kaplan - Meier method, LAG-3 expression was found to be correlated with poor overall survival (P = 0.020) and progression-free survival (P = 0.019). Multivariate analysis revealed LAG-3 expression (hazard ratio [HR] = 1.86; 95% confidence interval [CI], 1.00 - 3.44, P = 0.049) and residual tumor (HR = 9.71; 95% CI, 5.13 - 18.52, P < 0.001) as independent prognostic factors.

CONCLUSION

Our study demonstrated that LAG-3 expression in patients with OCCC may be a useful biomarker for the prognosis of OCCC and could serve as a new therapeutic target.

ICI-based therapies: A new strategy for oral potentially malignant disorders

Oral potentially malignant disorders (OPMDs) are linked with an escalated risk of developing cancers, particularly oral squamous cell carcinoma (OSCC). Since prevailing therapies cannot effectively forestall the exacerbation and recurrence of OPMDs, halting their malignant progression is paramount. The immune checkpoint serves as a cardinal regulator of the immune response and the primary cause of adaptive immunological resistance. Although the exact mechanism remains elusive, elevated expression of multiple immune checkpoints in OPMDs and OSCC relative to healthy oral mucosa has been ascertained. This review delves into the immunosuppressive microenvironment of OPMDs, the expression of diverse immune checkpoints such as programmed death receptor-1 (PD-1) and programmed death receptor-1 ligand (PD-L1) in OPMDs, and the potential application of corresponding inhibitors. In addition, synergistic strategies incorporating combined immune checkpoint inhibitors, such as cGAS-STING, costimulatory molecules, cancer vaccines, and hydrogels, are discussed to gain a more comprehensive understanding of the role and application of immune checkpoint inhibitors (ICIs) in oral carcinogenesis.

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.

Current Strategy to Treat Immunogenic Gastrointestinal Cancers: Perspectives for a New Era

Since pembrolizumab, an anti-programmed death-1 (PD-1) antibody, showed a dramatic response to immunogenic cancers with microsatellite instability-high (MSI-H) and/or deficient mismatch repair (dMMR) in the pilot clinical trial KEYNOTE-016, subsequent studies have confirmed durable responses of anti-PD-1 inhibitors for MSI-H/dMMR solid tumors. As immunotherapy is described as a "game changer," the therapeutic landscape for MSI-H/dMMR solid tumors including gastrointestinal cancers has changed considerably in the last decade. An MSI/MMR status has been established as the predictive biomarker for immune checkpoint blockades, playing an indispensable role in the clinical practice of patients with MSI-H/dMMR tumors. Immunotherapy is also now investigated for locally advanced MSI-H/dMMR gastrointestinal cancers. Despite this great success, a few populations with MSI-H/dMMR gastrointestinal cancers do not respond to immunotherapy, possibly due to the existence of intrinsic or acquired resistance mechanisms. Clarifying the underlying mechanisms of resistance remains a future task, whereas attempts to overcome resistance and improve the efficacy of immunotherapy are currently ongoing. Herein, we review recent clinical trials with special attention to MSI-H/dMMR gastrointestinal cancers together with basic/translational findings, which provide their rationale, and discuss perspectives for the further therapeutic development of treatment in this field.

Classic and new strategies for the treatment of advanced melanoma and non-melanoma skin cancer

Advanced melanoma and non-melanoma skin cancers (NMSCs) are burdened with a dismal prognosis. To improve the survival of these patients, studies on immunotherapy and target therapies in melanoma and NMSCs are rapidly increasing. BRAF and MEK inhibitors improve clinical outcomes, and anti-PD1 therapy demonstrates better results than chemotherapy or anti-CTLA4 therapy in terms of the survival of patients with advanced melanoma. In recent years, the combination therapy of nivolumab plus ipilimumab has gained ground in studies for its survival and response rate benefits in patients with advanced melanoma. In addition, neoadjuvant treatment for stages III and IV melanoma, either as monotherapy or combination therapy, has recently been discussed. Another promising strategy evaluated in recent studies is the triple combination of anti-PD-1/PD-L1 immunotherapy and anti-BRAF plus anti-MEK targeted therapy. On the contrary, in advanced and metastatic BCC, successful therapeutic strategies, such as vismodegib and sonidegib, are based on the inhibition of aberrant activation of the Hedgehog signaling pathway. In these patients, anti-PD-1 therapy with cemiplimab should be reserved as the second-line therapy in case of disease progression or poor response. In patients with locally advanced or metastatic SCC, who are not candidates for surgery or radiotherapy, anti-PD1 agents such as cemiplimab, pembrolizumab, and cosibelimab (CK-301) have shown significant results in terms of response rate. PD-1/PD-L1 inhibitors, such as avelumab, have also been used in Merkel carcinoma, achieving responses in half of the patients with advanced disease. The latest prospect emerging for MCC is the locoregional approach involving the injection of drugs that can stimulate the immune system. Two of the most promising molecules used in combination with immunotherapy are cavrotolimod (a Toll-like receptor 9 agonist) and a Toll-like receptor 7/8 agonist. Another area of study is cellular immunotherapy with natural killer cells stimulated with an IL-15 analog or CD4/CD8 cells stimulated with tumor neoantigens. Neoadjuvant treatment with cemiplimab in CSCCs and nivolumab in MCCs has shown promising results. Despite the successes of these new drugs, the new challenges ahead will be to select patients who will benefit from these treatments based on biomarkers and parameters of the tumor microenvironment.

LAG-3+ tumor-infiltrating lymphocytes ameliorates overall survival in triple-negative breast cancer patients

Purpose

Immune checkpoint molecule lymphocyte-activating gene-3 (LAG-3), which is expressed on active lymphocytes, has proven to be associated with immunosuppression and cancer progression in a variety of solid tumors. However, the role of LAG-3⁺ lymphocytes in human breast cancer (BC) is still not conclusive. We therefore performed a meta-analysis to clarify the role of these cells in prognosis prediction for BC.

Methods

We searched PubMed, Embase, and EBSCO to identify the studies evaluating the association of LAG-3⁺ lymphocyte infiltration and overall survival (OS) and/or disease-free survival (DFS) in BC patients, then combined extracted data with STATA 12.0.

Results

Eight published studies involving 5,859 BC patients were incorporated into this meta-analysis. We noted that a high number of LAG-3⁺ tumor-infiltrating lymphocytes were not appreciably associated with OS and DFS in BC patients. Strikingly, in stratified analyses based on the molecular type of BC, LAG-3⁺ lymphocyte infiltration was remarkably associated with better OS rather than DFS in triple-negative breast cancer (TNBC), whereas it significantly influenced neither OS nor DFS in Her2-positive BC. However, an increased density of these lymphocytes indicated a trend for better OS in Her2-positive BC. In addition, we found that LAG-3⁺ lymphocyte infiltration was also remarkably associated with prolonged OS in Her2-positive BC patients when they were measured by immunohistochemistry (IHC). In addition, an elevated number of these lymphocytes did not correlate with pathological complete response rate or clinicopathological features including lymph node metastasis.

Conclusion

The infiltration of LAG-3⁺ lymphocytes ameliorates OS in TNBC and Her2-positive BC, implicating that it is a valuable prognostic biomarker, and applications of anti-LAG-3 antagonists may possibly be not a promising therapeutic strategy for human BC especially for TNBC.

Overexpression of LAG3, TIM3, and A2aR in adenoid cystic carcinoma and mucoepidermoid carcinoma

OBJECTIVE

Adenoid cystic carcinoma (AdCC) and mucoepidermoid carcinoma (MEC) are the two most frequent malignancies of salivary glands. This study aims to explore the expression and migration of LAG3, TIM3, and A2aR in AdCC and MEC, and the potential relationship with oncogenic signaling molecules and immunosuppressive cytokines.

MATERIALS AND METHODS

Custom made human salivary gland tissue microarrays included 81 AdCCs, 52 MECs, 76 normal salivary glands (NSG), and 14 pleomorphic adenoma (PMA) samples. Immunohistochemical analysis of lymphocyte activation gene 3 (LAG3), T-cell immunoglobulin and mucin domain-containing protein 3 (TIM3), adenosine 2a receptor (A2aR), oncogenic phosphorylated S6 kinase (p-S6) and ERK_1/2 (p-ERK_1/2 ), and TGF-β1 was performed with salivary gland tissue microarrays of human samples. The correlation of the immunostaining was analyzed based on a digital pathological system, and data were evaluated by hierarchical cluster. Further in vitro studies of knockdown immune checkpoints LAG3, TIM3, and A2aR were carried out by siRNA transfection.

RESULTS

The expression levels of LAG3, TIM3, and A2aR were remarkably increased in AdCC and MEC, compared with NSG and PMA samples, but were independent of pathology grade. They were closely correlated with TGF-β1, slightly related to p-ERK_1/2 and p-S6. After the knockdown of immune checkpoints LAG3, TIM3, and A2aR, the migration of SACC-LM cell line was significantly reduced.

CONCLUSIONS

These results suggested that LAG3, TIM3, and A2aR are overexpressed in AdCC and MEC, may promote migration of SACC-LM cell and correlated with TGF-β1 and oncogenic signaling pathways.

Acidosis significantly alters immune checkpoint expression profiles of T cells from oesophageal adenocarcinoma patients

Tumour acidosis contributes to cancer progression by inhibiting anti-tumour immunity. However, the effect of acidosis on anti-tumour T cell phenotypes in oesophageal adenocarcinoma (OAC) is unknown. Therefore, this study investigated the effect of acidosis on anti-tumour T cell profiles and if immune checkpoint blockade (ICB) could enhance anti-tumour T cell immunity under acidosis. Acidic conditions substantially altered immune checkpoint expression profiles of OAC patient-derived T cells, upregulating TIM-3, LAG-3 and CTLA-4. Severe acidosis (pH 5.5) significantly decreased the percentage of central memory CD4⁺ T cells, an effect that was attenuated by ICB treatment. ICB increased T cell production of IFN-γ under moderate acidosis (pH 6.6) but not severe acidosis (pH 5.5) and decreased IL-10 production by T cells under severe acidic conditions only. A link between lactate and metastasis was also depicted; patients with nodal metastasis had higher serum lactate levels (p = 0.07) which also positively correlated with circulating levels of pro-angiogenic factor Tie-2. Our findings establish that acidosis-induced upregulation of immune checkpoints on T cells may potentially contribute to immune evasion and disease progression in OAC. However, acidic conditions curtailed ICB efficacy, supporting a rationale for utilizing systemic oral buffers to neutralize tumour acidity to improve ICB efficacy. Study schematic-PBMCs were isolated from OAC patients (A) and expanded ex vivo for 7 days using anti-CD3/28 +IL-2 T cell activation protocol (B) and further cultured for 48 h under increasing acidic conditions in the absence or presence of immune checkpoint blockade (nivolumab, ipilimumab or dual nivolumab + ipilimumab) (C). Immunophenotyping was then carried out to assess immune checkpoint expression profiles and anti-tumour T cell phenotypes (D). Serum lactate was assessed in OAC patients (E-F) and levels were correlated with patient demographics (G) and the levels of circulating immune/pro-angiogenic cytokines that were determined by multiplex ELISA (H). Key Findings-severe acidic conditions upregulated multiple immune checkpoints on T cells (I). Efficacy of ICB was curtailed under severe acidic conditions (J). Circulating lactate levels positively correlated with circulating levels of pro-angiogenic factor tie-2 and higher serum lactate levels were found in patients who had nodal metastasis (K).

Advancements in Cancer Immunotherapies

Recent work has suggested involvement of the immune system in biological therapies specifically targeting tumor microenvironment. Substantial advancement in the treatment of malignant tumors utilizing immune cells, most importantly T cells that play a key role in cell-mediated immunity, have led to success in clinical trials. Therefore, this article focuses on the therapeutic approaches and developmental strategies to treat cancer. This review emphasizes the immunomodulatory response, the involvement of key tumor-infiltrating cells, the mechanistic aspects, and prognostic biomarkers. We also cover recent advancements in therapeutic strategies.

Establishment and validation of a redox-related long non-coding RNAs prognostic signature in head and neck squamous cell carcinoma

Reduction and oxidation (redox) reactions occur in living organisms as part of normal cellular metabolism. Here, we established a novel redox-related long non-coding RNAs (rrlncRNAs) signature to predict the prognosis and therapeutic response in Head and neck squamous cell carcinoma (HNSCC). The expression profile and clinical information were obtained from the TCGA project. In total, 10 differently expressed rrlncRNAs associated with prognosis were identified and involved in a prognostic risk score signature by the least absolute shrinkage and selection operator penalized Cox analysis. The area under the receiver operating characteristic curves of the survival rates predicted by the rrlncRNAs signature over one, two, and three years were found to be 0.651, 0.670, and 0.679. Following the completion of the Kaplan-Meier survival study, we discovered that the lower-risk cohort exhibited a much longer overall survival period in contrast with the higher-risk cohort. Univariate and multivariable Cox regression analyses demonstrated that the risk score independently served as a significant predictive factor. GO annotation and KEGG pathway analyses illustrated that the rrlncRNAs signature was strongly associated with immune-related functions as well as signaling pathways. The tumor-infiltrating immune cells, tumor microenvironment, immune-related functions, HLA gene family expression, immune checkpoint genes expression, and somatic variants differed substantially between the low- and high-risk cohorts. Moreover, patients in low-risk group were predicted to present a favorable immunotherapy responsiveness, while in contrast, the high-risk group patients might have a stronger sensitivity to "docetaxel". According to our findings, the rrlncRNAs signature showed an excellent prognosis predictive value and might indicate therapeutic response to immunotherapy in HNSCC.

Prognostic value of tumor-infiltrating immune cells and immune checkpoints in elderly head-and-neck squamous cell carcinoma patients undergoing definitive (chemo)radiotherapy

Background and purpose

Tumor-infiltrating lymphocytes (TILs) are associated with locoregional control (LRC) in head-and-neck squamous cell carcinoma (HNSCC) patients undergoing (chemo)radiotherapy. As immunosenescence results in reduced immune activity, the role of TILs in elderly HNSCC patients may differ compared to younger patients, providing a rationale to study the prognostic role of TILs and immune checkpoints (ICs) in this population.

Material and methods

Sixty-three HNSCC patients aged ≥ 65 years undergoing definitive (chemo)radiotherapy between 2010 and 2019 with sufficient material from pre-treatment biopsies were included in the analysis. Immunohistochemical stainings of CD3, CD4, CD8, PD-L1, TIM3, LAG3, TIGIT and CD96, and of osteopontin as an immunosenescence-associated protein were performed. Overall survival (OS) and progression-free survival (PFS) were determined using the Kaplan–Meier method, and Fine-Gray's models were used for locoregional failure (LRF) analyses.

Results

While there was no correlation between patient age and IC expression, osteopontin levels correlated with increasing age (r = 0.322, p < 0.05). Two-year OS, PFS, and LRC were 44%, 34%, and 71%, respectively. Increased LAG3 expression, both intraepithelial (SHR = 0.33, p < 0.05) and stromal (SHR = 0.38, p < 0.05), and elevated stromal TIM3 expression (SHR = 0.32, p < 0.05) corresponded with reduced LRFs. Absent tumoral PD-L1 expression (TPS = 0%) was associated with more LRFs (SHR = 0.28, p < 0.05). There was a trend towards improved LRF rates in elderly patients with increased intraepithelial CD3 + (SHR = 0.52, p = 0.07) and CD8 + (SHR = 0.52, p = 0.09) TIL levels.

Conclusion

LAG3, TIM3 and TPS are promising biomarkers in elderly HNSCC patients receiving (chemo)radiotherapy. Considering the frequency of non-cancer related deaths in this population, the prognostic value of these biomarkers primarily relates to LRC.

Single-cell transcriptomic profiling for inferring tumor origin and mechanisms of therapeutic resistance

Head and Neck Squamous Cell Carcinoma (HNSCC) is an aggressive epithelial cancer with poor overall response rates to checkpoint inhibitor therapy (CPI) despite CPI being the recommended treatment for recurrent or metastatic HNSCC. Mechanisms of resistance to CPI in HNSCC are poorly understood. To identify drivers of response and resistance to CPI in a unique patient who was believed to have developed three separate HNSCCs, we performed single-cell RNA-seq (scRNA-seq) profiling of two responding lesions and one progressive lesion that developed during CPI. Our results not only suggest interferon-induced APOBEC3-mediated acquired resistance as a mechanism of CPI resistance in the progressing lesion but further, that the lesion in question was actually a metastasis as opposed to a new primary tumor, highlighting the immense power of scRNA-seq as a clinical tool for inferring tumor origin and mechanisms of therapeutic resistance.

Emerging Trends in Immunotherapy for Cancer

Recent advances in cancer immunology have enabled the discovery of promising immunotherapies for various malignancies that have shifted the cancer treatment paradigm. The innovative research and clinical advancements of immunotherapy approaches have prolonged the survival of patients with relapsed or refractory metastatic cancers. Since the U.S. FDA approved the first immune checkpoint inhibitor in 2011, the field of cancer immunotherapy has grown exponentially. Multiple therapeutic approaches or agents to manipulate different aspects of the immune system are currently in development. These include cancer vaccines, adoptive cell therapies (such as CAR-T or NK cell therapy), monoclonal antibodies, cytokine therapies, oncolytic viruses, and inhibitors targeting immune checkpoints that have demonstrated promising clinical efficacy. Multiple immunotherapeutic approaches have been approved for specific cancer treatments, while others are currently in preclinical and clinical trial stages. Given the success of immunotherapy, there has been a tremendous thrust to improve the clinical efficacy of various agents and strategies implemented so far. Here, we present a comprehensive overview of the development and clinical implementation of various immunotherapy approaches currently being used to treat cancer. We also highlight the latest developments, emerging trends, limitations, and future promises of cancer immunotherapy.

LAG-3 as a Potent Target for Novel Anticancer Therapies of a Wide Range of Tumors

LAG-3 (Lymphocyte activation gene 3) protein is a checkpoint receptor that interacts with LSEC-tin, Galectin-3 and FGL1. This interaction leads to reduced production of IL-2 and IFN-γ. LAG-3 is widely expressed in different tumor types and modulates the tumor microenvironment through immunosuppressive effects. Differential expression in various tumor types influences patient prognosis, which is often associated with coexpression with immune checkpoint inhibitors, such as TIM-3, PD-1 and CTLA-4. Here, we discuss expression profiles in different tumor types. To date, many clinical trials have been conducted using LAG-3 inhibitors, which can be divided into anti-LAG-3 monoclonal antibodies, anti-LAG-3 bispecifics and soluble LAG-3-Ig fusion proteins. LAG-3 inhibitors supress T-cell proliferation and activation by disallowing for the interaction between LAG-3 to MHC-II. The process enhances anti-tumor immune response. In this paper, we will review the current state of knowledge on the structure, function and expression of LAG-3 in various types of cancer, as well as its correlation with overall prognosis, involvement in cell-based therapies and experimental medicine. We will consider the role of compounds targeting LAG-3 in clinical trials both as monotherapy and in combination, which will provide data relating to the efficacy and safety of proposed drug candidates.

Current status and perspective of tumor immunotherapy for head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) have a high incidence and mortality rate, and investigating the pathogenesis and potential therapeutic strategies of HNSCC is required for further progress. Immunotherapy is a considerable therapeutic strategy for HNSCC due to its potential to produce a broad and long-lasting antitumor response. However, immune escape, which involves mechanisms including dyregulation of cytokines, perturbation of immune checkpoints, and recruitment of inhibitory cell populations, limit the efficacy of immunotherapy. Currently, multiple immunotherapy strategies for HNSCC have been exploited, including immune checkpoint inhibitors, costimulatory agonists, antigenic vaccines, oncolytic virus therapy, adoptive T cell transfer (ACT), and epidermal growth factor receptor (EGFR)-targeted therapy. Each of these strategies has unique advantages, and the appropriate application of these immunotherapies in HNSCC treatment has significant value for patients. Therefore, this review comprehensively summarizes the mechanisms of immune escape and the characteristics of different immunotherapy strategies in HNSCC to provide a foundation and consideration for the clinical treatment of HNSCC.

Implications of regulatory T cells in anti-cancer immunity: from pathogenesis to therapeutics

Regulatory T cells (Tregs) play an essential role in maintaining immune tolerance and suppressing inflammation. However, Tregs present major hurdle in eliciting potent anti-cancer immune responses. Therefore, curbing the activity of Tregs represents a novel and efficient way towards successful immunotherapy of cancer. Moreover, there is an emerging interest in harnessing Treg-based strategies for augmenting anti-cancer immunity in different types of the disease. This review summarises the crucial mechanisms of Tregs’ mediated suppression of anti-cancer immunity and strategies to suppress or to alter such Tregs to improve the immune response against tumors. Highlighting important clinical studies, the review also describes current Treg-based therapeutic interventions in cancer, and discusses Treg-suppression by molecular targeting, which may emerge as an effective cancer immunotherapy and as an alternative to detrimental chemotherapeutic agents.

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Tregs are crucial in maintaining immune tolerance and suppressing inflammation.

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Tregs present a major obstacle to eliciting potent anti-tumor immune responses.

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The review summarizes current Treg-based therapeutic interventions in cancer.

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Treg can be an effective cancer immunotherapy target.

Cutting-Edge: Preclinical and Clinical Development of the First Approved Lag-3 Inhibitor

Immune checkpoint inhibitors (ICIs) have revolutionized medical practice in oncology since the FDA approval of the first ICI 11 years ago. In light of this, Lymphocyte-Activation Gene 3 (LAG-3) is one of the most important next-generation immune checkpoint molecules, playing a similar role as Programmed cell Death protein 1 (PD-1) and Cytotoxic T-Lymphocyte Antigen 4 (CTLA-4). 19 LAG-3 targeting molecules are being evaluated at 108 clinical trials which are demonstrating positive results, including promising bispecific molecules targeting LAG-3 simultaneously with other ICIs. Recently, a new dual anti-PD-1 (Nivolumab) and anti-LAG-3 (Relatimab) treatment developed by Bristol Myers Squibb (Opdualag), was approved by the Food and Drug Administration (FDA) as the first LAG-3 blocking antibody combination for unresectable or metastatic melanoma. This novel immunotherapy combination more than doubled median progression-free survival (PFS) when compared to nivolumab monotherapy (10.1 months versus 4.6 months). Here, we analyze the large clinical trial responsible for this historical approval (RELATIVITY-047), and discuss the preclinical and clinical developments that led to its jump into clinical practice. We will also summarize results achieved by other LAG-3 targeting molecules with promising anti-tumor activities currently under clinical development in phases I, I/II, II, and III. Opdualag will boost the entry of more LAG-3 targeting molecules into clinical practice, supporting the accumulating evidence highlighting the pivotal role of LAG-3 in cancer.

Immunotherapy: Reshape the Tumor Immune Microenvironment

Tumor immune microenvironment (TIME) include tumor cells, immune cells, cytokines, etc. The interactions between these components, which are divided into anti-tumor and pro-tumor, determine the trend of anti-tumor immunity. Although the immune system can eliminate tumor through the cancer-immune cycle, tumors appear to eventually evade from immune surveillance by shaping an immunosuppressive microenvironment. Immunotherapy reshapes the TIME and restores the tumor killing ability of anti-tumor immune cells. Herein, we review the function of immune cells within the TIME and discuss the contribution of current mainstream immunotherapeutic approaches to remolding the TIME. Changes in the immune microenvironment in different forms under the intervention of immunotherapy can shed light on better combination treatment strategies.

Analysis of the immune checkpoint lymphocyte activation gene-3 (LAG-3) in endometrial cancer: An emerging target for immunotherapy

BACKGROUND

Lymphocyte activation gene-3 (LAG-3) is a novel molecule that participates in the immune escape of tumor cells and is a target for immunotherapy. However, the expression of LAG-3 in patients with endometrial cancer (EC) has not been comprehensively characterized.

OBJECTIVES

We elucidated the expression of LAG-3 and investigated its correlation with clinicopathological parameters, ProMisE subtypes, CD8⁺ T-cell infiltration and relapse-free survival (RFS) in a retrospective cohort of 421 patients with endometrial cancer.

METHODS

Next-generation sequencing of the polymerase epsilon (POLE) and immunohistochemistry of mismatch repair (MMR)-related protein (MLH1, PMS2, MSH2, and MSH6), p53, CD8 and LAG-3 protein in whole sections were performed.

RESULTS

Positive LAG-3 was detected in tumor cells (TCs) and immune cells (ICs) in 31.6% (133/421) and 24.0% (101/421) of the patients, respectively. LAG-3 positivity in ICs was more common in high-grade, high-intermediate risk, high-risk, and advanced/metastatic subgroups and was relevant to lymphovascular space invasion, while that in TCs was more common in older individuals (≥54 years). LAG-3 expression was more prevalent in POLE ultramutated (POLEmut) and MMR-deficient (MMRd) EC than in p53-abnormal (p53abn) and p53-wild (p53wt) EC in TCs (34.4 % and 66.3% in POLEmut and MMRd versus 28.6% and 19.5% in p53abn and p53wt, P < 0.001) and ICs (78.1 % and 65.1% in POLEmut and MMRd versus 2.9% and 5.2% in p53abn and p53wt, P < 0.001). Positive expression of LAG-3 in TCs and ICs was associated with high levels of tumor-associated CD8⁺ T-cell immune infiltration. Additionally, LAG-3 positivity in TCs was related to improved RFS.

CONCLUSIONS

This study suggests that immunotherapy targeting LAG-3 may play a role in EC patients with POLEmut or MMRd molecular markers. Positive LAG-3 expression in TCs may be a predictor of improved RFS.

Characterization of the Immune Response to PD-1 Blockade during Chemoradiotherapy for Head and Neck Squamous Cell Carcinoma

BACKGROUND

Chemoradiotherapy is a standard treatment for HNSCC. Blockade of the PD-1/L1-2 interaction may represent a target to overcome immune escape during this treatment.

METHODS

Utilizing a HNSCC mEERL C57BL/6 mouse model, we evaluated a PD-1 blockade alone or in combination with cisplatin-based chemoradiotherapy. Next, we evaluated peripheral blood mononuclear cells (PBMCs) with relative PD-1, TIM-3, and LAG-3 expression, and myeloid-derived suppressor-like (MDSC-like) populations from a clinical trial evaluating PD-1 blockade with chemoradiotherapy in HNSCC. Finally, we analyzed the effect of therapy on human T-cell clonality through T-cell Receptor (TCR) sequencing.

RESULTS

Anti-PD-1 monotherapy induced no response in the mEERL model; however, combination with chemoradiotherapy improved tumor clearance and survival. PBMCs from patients treated with this combination therapy demonstrate a decline in circulating T-cell populations with knockdown of PD-1 expressing CD3+CD4+ and CD3+CD8+ T cells during treatment. However, TIM-3, LAG-3 expressing T-cell and MDSC-like populations concordantly rose. During treatment, the TCR repertoire demonstrates overall clonal expansion, with both unique and previously reported T-cell clones.

CONCLUSIONS

Our murine HNSCC model demonstrates efficacy of PD-1 blockade during chemoradiotherapy. However, while PD-1-expressing T cells decreased with this therapy, human PBMC findings also identified an increase in populations contributing to immune exhaustion. These findings further characterize PD-1 blockade during chemoradiotherapy for HNSCC and highlight potential competing mechanisms of immune evasion.

Lag3: From Bench to Bedside

The introduction of immune checkpoint inhibitors represented a breakthrough treatment for metastatic melanoma, but the effect of these agents is not limited to a single cancer type. Promising results have been reported in various solid tumors, for example, lung cancer. The success of these drugs depends on the activation of tumor-infiltrating lymphocytes and primary and acquired resistance have been reported alongside a high rate of immune-related adverse events when agents targeting different immune checkpoints are given in combination. Numerous other targets have been investigated to overcome the resistance, improve the activity, and reduce the toxicity of checkpoint inhibitor therapy. Among these, the most promising is Lymphocyte-activation gene 3 (LAG-3), a transmembrane protein involved in cytokine release and inhibitory signaling in T cells. Preclinical data showed that LAG-3 is a negative regulator of both CD4⁺ T cell and CD8⁺ T cell and the activity on CD8⁺ T cell is independent of CD4⁺ activation. On the CD8⁺ T cell, LAG-3 activation abrogates the antigen presentation whereas on the CD4⁺ T cell, arrests the S phase of the cell cycle. The blockade of LAG-3 has been tested in several combination therapies, and recent clinical data showed a good safety profile and a synergistic effect with anti-PD-1, suggesting that this combination could become a standard treatment for metastatic melanoma. In this review, we report the available preclinical data and the new clinical data on LAG-3 blockade in different solid tumors, and we discuss LAG-3 as potential prognostic and predictive factor, together with possible future applications.

The Immune Checkpoint Inhibitor LAG-3 and Its Ligand GAL-3 in Vulvar Squamous Neoplasia

Vulvar squamous cell carcinoma (vSCC), although rare, carries significant morbidity and a high rate of recurrence. Treatment options beyond surgical excision remain limited. Lymphocyte activation gene-3 (LAG-3) and its binding partner galectin-3 (GAL-3) are an immuno-inhibitory checkpoint pair that represent potential immunotherapy targets for the treatment of vSCC. This study examined the expression of LAG-3 and GAL-3 alongside programmed cell death ligand-1 expression in invasive SCC and vulvar intraepithelial neoplasia (VIN) by immunohistochemical analysis of formalin-fixed paraffin-embedded tissue. A total of 35 cases were selected for evaluation: 13 VIN3 [human papillomavirus (HPV)-associated VIN/usual-type VIN], 2 differentiated VIN (dVIN), 16 HPV-associated vSCC, and 4 dVIN-associated vSCC. LAG-3+ tumor-infiltrating lymphocytes were identified in 91% (32/35) of cases of vulvar squamous neoplasia. Tumor cells were positive for GAL-3 in 71% of the vulvar neoplasia cases. HPV-associated vSCC was more likely to demonstrate GAL-3 tumoral positivity when compared with dVIN-associated vSCC (24/29 vs. 1/6, P=0.004). We observed co-expression of all 3 immunomarkers in 40% (14/35) of cases evaluated. In light of these findings, use of immunomodulatory drugs that target the LAG-3/GAL-3 pathway may be potentially beneficial in vSCC and efficacy may be increased when combined with anti-programmed cell death ligand-1 therapy.

Update on lymphocyte-activation gene 3 (LAG-3) in cancers: from biological properties to clinical applications

Immunotherapy that targets checkpoints, especially programmed cell death protein 1 and programmed cell death ligand 1, has revolutionized cancer therapy regimens. The overall response rate to mono-immunotherapy, however, is limited, emphasizing the need to potentiate the efficacy of these regimens. The functions of immune cells are modulated by multiple stimulatory and inhibitory molecules, including lymphocyte activation gene 3 (LAG-3). LAG-3 is co-expressed together with other inhibitory checkpoints and plays key roles in immune suppression. Increasing evidence, particularly in the last 5 years, has shown the potential of LAG-3 blockade in anti-tumor immunity. This review provides an update on the biological properties and clinical applications of LAG-3 in cancers.

Combination of genetically engineered T cells and immune checkpoint blockade for the treatment of cancer

Immune checkpoint (IC) blockade using monoclonal antibodies is currently one of the most successful immunotherapeutic interventions to treat cancer. By reinvigorating antitumor exhausted T cells, this approach can lead to durable clinical responses. However, the majority of patients either does not respond or present a short-lived response to IC blockade, in part due to a scarcity of tumor-specific T cells within the tumor microenvironment. Adoptive transfer of T cells genetically engineered to express chimeric antigen receptors (CARs) or engineered T cell receptors (TCRs) provide the necessary tumor-specific immune cell population to target cancer cells. However, this therapy has been considerably ineffective against solid tumors in part due to IC-mediated immunosuppressive effects within tumor microenvironment. These limitations could be overcome by associating adoptive cell transfer of genetically engineered T cells and IC blockade. In this comprehensive review, we highlight the strategies and outcomes of preclinical and clinical attempts to disrupt IC signaling in adoptive T cell transfer against cancer. These strategies include combined administration of genetically engineered T cells and IC inhibitors, engineered T cells with intrinsic modifications to disrupt IC signaling and the design of CARs against IC molecules. The current landscape indicates that the synergy of the fast-paced refinements of gene-editing technologies and synthetic biology and the increased comprehension of IC signaling will certainly translate into novel and more effective immunotherapeutic approaches to treat patients with cancer.

Mutational and immunologic Landscape in malignant Salivary Gland Tumors harbor the potential for novel therapeutic strategies

Salivary gland carcinomas (SGC) are rare (3-6 % of all head and neck cancers) and show biological heterogeneity depending on the respective histological subtype. While complete surgical resection is the standard treatment for localized disease, chemotherapy or radiation therapy are frequently insufficient for the treatment of unresectable or metastasized SGC. Therefore, new therapeutic approaches such as molecularly targeted therapy or the application of immune checkpoint inhibition enhance the treatment repertoire. Accordingly, comprehensive analyses of the genomic landscape and the tumor-microenvironment (TME) are of crucial importance in order to optimize and individualize SGC treatment. This manuscript combines the current scientific knowledge of the composition of the mutational landscape and the TME in SGCs harboring the potential for novel (immune-) targeted therapeutic strategies.

Biomaterial-mediated modulation of oral microbiota synergizes with PD-1 blockade in mice with oral squamous cell carcinoma

Because a host's immune system is affected by host-microbiota interactions, means of modulating the microbiota could be leveraged to augment the effectiveness of cancer therapies. Here we report that patients with oral squamous cell carcinoma (OSCC) whose tumours contained higher levels of bacteria of the genus Peptostreptococcus had higher probability of long-term survival. We then show that in mice with murine OSCC tumours injected with oral microbiota from patients with OSCCs, antitumour responses were enhanced by the subcutaneous delivery of an adhesive hydrogel incorporating silver nanoparticles (which inhibited the growth of bacteria competing with Peptostreptococcus) alongside the intratumoural delivery of the bacterium P. anaerobius (which upregulated the levels of Peptostreptococcus). We also show that in mice with subcutaneous or orthotopic murine OSCC tumours, combination therapy with the two components (nanoparticle-incorporating hydrogel and exogenous P. anaerobius) synergized with checkpoint inhibition with programmed death-1. Our findings suggest that biomaterials can be designed to modulate human microbiota to augment antitumour immune responses.

A Novel Six Autophagy-Related Genes Signature Associated With Outcomes and Immune Microenvironment in Lower-Grade Glioma

Since autophagy and the immune microenvironment are deeply involved in the tumor development and progression of Lower-grade gliomas (LGG), our study aimed to construct an autophagy-related risk model for prognosis prediction and investigate the relationship between the immune microenvironment and risk signature in LGG. Therefore, we identified six autophagy-related genes (BAG1, PTK6, EEF2, PEA15, ITGA6, and MAP1LC3C) to build in the training cohort (n = 305 patients) and verify the prognostic model in the validation cohort (n = 128) and the whole cohort (n = 433), based on the data from The Cancer Genome Atlas (TCGA). The six-gene risk signature could divide LGG patients into high- and low-risk groups with distinct overall survival in multiple cohorts (all p < 0.001). The prognostic effect was assessed by area under the time-dependent ROC (t-ROC) analysis in the training, validation, and whole cohorts, in which the AUC value at the survival time of 5 years was 0.837, 0.755, and 0.803, respectively. Cox regression analysis demonstrated that the risk model was an independent risk predictor of OS (HR > 1, p < 0.05). A nomogram including the traditional clinical parameters and risk signature was constructed, and t-ROC, C-index, and calibration curves confirmed its robust predictive capacity. KM analysis revealed a significant difference in the subgroup analyses' survival. Functional enrichment analysis revealed that these autophagy-related signatures were mainly involved in the phagosome and immune-related pathways. Besides, we also found significant differences in immune cell infiltration and immunotherapy targets between risk groups. In conclusion, we built a powerful predictive signature and explored immune components (including immune cells and emerging immunotherapy targets) in LGG.

Serum LAG-3 Predicts Outcome and Treatment Response in Hepatocellular Carcinoma Patients With Transarterial Chemoembolization

Background

Transarterial chemoembolization (TACE) stands for the most commonly utilized therapy for hepatocellular carcinoma (HCC) worldwide. This study was to explore the potential predictive and prognostic roles of LAG-3 and PD-L1 as serum biomarkers in HCC patients underwent TACE treatment.

Methods

A total of 100 HCC patients receiving TACE as well as 30 healthy controls were enrolled in the study. Serum LAG-3 and PD-L1 levels were determined at baseline and 3 day after TACE using enzyme-linked immunosorbent assay (ELISA).

Results

We found serum levels of LAG-3 and PD-L1 were significantly elevated in HCC patients compared with healthy controls. Interestingly, patients with low pre-TACE and post-TACE levels of LAG-3 but not PD-L1 had a high probability of achieving an objective response (OR) after TACE treatment. Additionally, high pre-TACE LAG-3 level was correlated with poor disease outcome, and the patients with both high serum LAG-3 and PD-L1 level had the shorter overall survival (OS) than patients who are either PD-L1 or LAG-3 high or both PD-L1 and LAG-3 low. High pre-TACE serum LAG-3 level was positively associated with more cirrhosis pattern, advanced BCLC stage, pre-TACE alanine aminotransferase (ALT) level, and pre-TACE aspartate aminotransferase (AST) level. Furthermore, in 50 patients who underwent TACE, the serum LAG-3 level was significantly decreased at 3 day after TACE.

Conclusion

Both pre-TACE and post-TACE serum LAG-3 levels could serve as powerful predictors for tumor response of TACE, and high pre-TACE serum LAG-3 level was an indicator for poor prognosis in HCC.

Tumor microenvironment and immune evasion in head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC), an aggressive malignancy, is characterized by high morbidity and low survival rates with limited therapeutic options outside of regional surgery, conventional cytotoxic chemotherapy, and irradiation. Increasing studies have supported the synergistic role of the tumor microenvironment (TME) in cancer advancement. The immune system, in particular, plays a key role in surveillance against the initiation, development, and progression of HNSCC. The understanding of how neoplastic cells evolve and evade the immune system whether through self-immunogenicity manipulation, or expression of immunosuppressive mediators, provides the foundation for the development of advanced therapies. Furthermore, the crosstalk between cancer cells and the host immune system have a detrimental effect on the TME promoting angiogenesis, proliferation, and metastasis. This review provides a recent insight into the role of the key inflammatory cells infiltrating the TME, with a focus on reviewing immunological principles related to HNSCC, as cancer immunosurveillance and immune escape, including a brief overview of current immunotherapeutic strategies and ongoing clinical trials.

The Role of Soluble LAG3 and Soluble Immune Checkpoints Profile in Advanced Head and Neck Cancer: A Pilot Study

Unresectable recurrent and/or metastatic head and neck squamous cell carcinoma (R/M HNSCC) has a very poor prognosis. Soluble immune checkpoints (sICs) are circulating proteins that result from the alternative splicing of membrane proteins and can modulate the immune response to cancer cells. The aim of our pilot study was to determine the possible role of a comprehensive evaluation of sICs in the classification of prognosis and response to treatment in patients with advanced disease. We evaluated several sICs (CD137, CTLA-4, PD-1, PD-L1, PD-L2, TIM3, LAG3, GITR, HVEM, BTLA, IDO, CD80, CD27, and CD28) from peripheral blood at baseline and investigated the association with clinical characteristics and outcomes. A high baseline soluble LAG3 (sLAG3 > 377 pg/mL) resulted in an association with poor PFS and OS (p = 0.047 and p = 0.003, respectively). Moreover, sLAG3 emerged as an independent prognostic factor using an MVA (p = 0.005). The evaluation of sICs, in particular sLAG3, may be relevant for identifying patients with worse prognoses, or resistance to treatments, and may lead to the development of novel targeted strategies.

Preoperative Immunotherapy in the Multidisciplinary Management of Oral Cavity Cancer

Despite advances in multimodal treatment for oral cavity squamous cell carcinoma, recurrence rates remain high, providing an opportunity for new therapeutic modalities that may improve oncologic outcomes. Much recent attention has been paid to the molecular interactions between the tumor cells with the adjacent peritumoral microenvironment, in which immunosuppressive molecular changes create a landscape that promotes tumor progression. The rationale for the introduction of immunotherapy is to reverse the balance of these immune interactions in a way that utilizes the host immune system to attack tumor cells. In the preoperative setting, immunotherapy has the advantage of priming the unresected tumor and the associated native immune infiltration, supercharging the adaptive anti-tumor immune response. It also provides the basis for scientific discovery where the molecular profile of responders can be interrogated to elucidate prognostic markers to aid in future patient selection. Preoperative immunotherapy is not without limitations. The risk of surgical delay due to immune adverse events must be carefully discussed by members of a multidisciplinary treatment team and patient selection will be critical. One day, the discovery of predictive biomarkers may allow for algorithms where pre-surgical immunotherapy decreases the size of surgical defect and impacts the intensity of adjuvant therapy leading to improved patient survival and decreased morbidity. With further study, immunotherapy could become a key component of future treatment algorithm.

Gene of the month: lymphocyte-activation gene 3 (LAG-3)

Lymphocyte-activation gene 3 (LAG-3) is a coreceptor found on activated T-lymphocytes activated B-lymphocytes and natural killer (NK) cells. It is closely related to CD4 where it shares multiple common and divergent features. It contains specific binding sites with high affinity to major histocompatibility complex (MHC) Class II and functions as an inhibitor of T-cell signalling. Tumour-infiltrating lymphocytes with high LAG-3 expression have been found in many solid tumours including ovarian cancer, melanoma, colorectal cancer and haematological malignancies including Hodgkin and diffuse large B-cell lymphoma. LAG-3 antagonism has been demonstrated to restore the anti-tumourigenic function of T-cells in vivo, however, mechanistic knowledge remains relatively poorly defined. As other immune checkpoint inhibitors have transformed the management of difficult to treat cancers, such as melanoma, it is hoped that LAG-3 might have the same potential. This review will explore LAG-3 modulation as an anticancer therapy, highlighting recent clinical developments.