Tumor microenvironmental modification by the current target therapy for head and neck squamous cell carcinoma

Immunotherapeutic strategies in head and neck cancer: challenges and opportunities

HNSCC remains a substantial health issue, with treatment options including surgery, radiation, and platinum-based chemotherapy. Unfortunately, despite progress in research, only modest gains have been made in disease control, with existing treatments resulting in significant functional and quality-of-life issues. The introduction of immunotherapy in the treatment of HNSCC has resulted in some improvements in outlook for patients and is now standard of care for populations with both recurrent and metastatic disease. However, despite the early successes, responses to immune checkpoint inhibition (ICI) remain modest to low, approaching 14%-22% objective response rates. Challenges to the effectiveness of ICI and other immunotherapies are complex, including the diverse and dynamic molecular plasticity and heterogeneity of HNSCCs; lack of immunogenic antigens; accumulated suppressive immune populations such as myeloid cells and dysfunctional T cells; nutrient depletion; and metabolic dysregulation in the HNSCC tumor microenvironment. In this Review, we explore the mechanisms responsible for immunotherapy resistance, dissect these challenges, and discuss potential opportunities for overcoming hurdles to the development of successful immunotherapy for HNSCC.

ADORA2B promotes proliferation and migration in head and neck squamous cell carcinoma and is associated with immune infiltration

BACKGROUND

Adenosine A2B receptor (ADORA2B), a G protein-coupled receptor, is implicated in tumor progression and immune regulation in various cancers. However, its specific role in head and neck squamous cell carcinoma (HNSC) remains largely unexplored. This study aims to elucidate the expression profile, prognostic value, immune modulatory role, and therapeutic potential of ADORA2B in HNSC.

METHODS

Comprehensive bioinformatics analyses were performed using TCGA and GEO datasets to evaluate ADORA2B expression, clinical correlations, and prognostic significance in HNSC. Weighted gene co-expression network analysis (WGCNA) and functional enrichment analyses were conducted to explore ADORA2B-associated pathways. Immune infiltration was assessed via ESTIMATE and single-sample gene set enrichment analysis (ssGSEA). Immune checkpoint blockade (ICB) therapy sensitivity and drug sensitivity were analyzed using the IMvigor210 and NCI-60 databases, respectively. In vitro experiments, including siRNA-mediated ADORA2B knockdown, CCK-8 assays, colony formation, and wound healing assays, were performed to validate the oncogenic role of ADORA2B.

RESULTS

ADORA2B was significantly overexpressed in HNSC tumor tissues compared to adjacent normal tissues, and its expression correlated with advanced clinical stage as well as poor overall survival (OS) and progression-free survival (PFS). Functional enrichment analyses revealed significant downregulation of immune-related pathways in high ADORA2B expression groups. High ADORA2B expression was associated with a more immunosuppressive tumor microenvironment (TME), characterized by lower immune and stromal scores and reduced immune cell infiltration. Immunotherapy response analysis demonstrated that patients with high ADORA2B expression exhibited poorer outcomes following ICB therapy. Drug sensitivity analysis identified several agents, including Ixazomib citrate, Masitinib, and others, as potential therapeutic candidates for high ADORA2B expression patients. In vitro experiments confirmed that ADORA2B knockdown significantly inhibited HNSC cell proliferation, colony formation, and migration, underscoring its critical role in tumor progression.

CONCLUSION

ADORA2B is a key oncogenic driver in HNSC, contributing to tumor proliferation, migration, and an immunosuppressive TME. Its high expression is associated with poor prognosis and reduced immunotherapy efficacy. Targeting ADORA2B may enhance therapeutic outcomes and overcome treatment resistance, highlighting its potential as a diagnostic, prognostic, and therapeutic biomarker.

STAT3 Signaling Pathway in Health and Disease

Signal transducer and activator of transcription 3 (STAT3) is a critical transcription factor involved in multiple physiological and pathological processes. While STAT3 plays an essential role in homeostasis, its persistent activation has been implicated in the pathogenesis of various diseases, particularly cancer, bone-related diseases, autoimmune disorders, inflammatory diseases, cardiovascular diseases, and neurodegenerative conditions. The interleukin-6/Janus kinase (JAK)/STAT3 signaling axis is central to STAT3 activation, influencing tumor microenvironment remodeling, angiogenesis, immune evasion, and therapy resistance. Despite extensive research, the precise mechanisms underlying dysregulated STAT3 signaling in disease progression remain incompletely understood, and no United States Food and Drug Administration (USFDA)-approved direct STAT3 inhibitors currently exist. This review provides a comprehensive evaluation of STAT3's role in health and disease, emphasizing its involvement in cancer stem cell maintenance, metastasis, inflammation, and drug resistance. We systematically discuss therapeutic strategies, including JAK inhibitors (tofacitinib, ruxolitinib), Src Homology 2 domain inhibitors (S3I-201, STATTIC), antisense oligonucleotides (AZD9150), and nanomedicine-based drug delivery systems, which enhance specificity and bioavailability while reducing toxicity. By integrating molecular mechanisms, disease pathology, and emerging therapeutic interventions, this review fills a critical knowledge gap in STAT3-targeted therapy. Our insights into STAT3 signaling crosstalk, epigenetic regulation, and resistance mechanisms offer a foundation for developing next-generation STAT3 inhibitors with greater clinical efficacy and translational potential.

Modeling and Interpretability Study of the Structure-Activity Relationship for Multigeneration EGFR Inhibitors

The fourth-generation EGFR inhibitors targeting L858R/T790M/C797S mutations are in clinical trials mostly, and it is necessary to develop new inhibitors. In this study, an internal data set containing 2302 multitarget EGFR inhibitors targeting the wild type (83%) and the L858R (92%), L858R/T790M (96%), and L858R/T790M/C797S (60%) mutations was collected. We established a structure-activity relationship model for predicting the bioactivities of multigeneration EGFR inhibitors by a multitask deep neural network (MT-DNN). We also constructed four single-task models on 1384 L858R/T790M/C797S (60%) mutation inhibitors by support vector machine (SVM), random forest (RF), XGBoost (XGB), and single-target neural network (ST-DNN), respectively. The MT-DNN model significantly outperformed single-task models on the external data set of 304 fourth-generation EGFR inhibitors. Furthermore, the combined application of MT-DNN and SHAP/delta-SHAP value interpretability analysis offers rigorous structural information from a global perspective. With SHAP/delta-SHAP methods, the MT-DNN model can mine the core scaffold and important fragments of multigeneration EGFR inhibitors and provide valuable information from a structure-activity relationship perspective to address the resistant mutation problem.

Causal role of immune cells in head and neck squamous cell carcinoma

Chronic inflammation, immune cell infiltration, and metabolic reprogramming play a crucial role in the development of head and neck squamous cell carcinoma (HNSCC). Based on the summary-level data from a genome-wide association study (GWAS), this study used Mendelian randomization (MR) analysis to investigate the causal relationship between immune cell phenotype and HNSCC. Two-step MR was employed to quantify the proportion of the effect of metabolite-mediated immunophenotypes on HNSCC. 16 immune phenotypes exhibited a causal relationship with HNSCC. HLA DR + CD4 + AC (OR: 1.31, 95% CI 1.07-1.59, P < 0.01) and EM CD8br AC cells (OR: 1.36, 95% CI 1.14-1.62, P < 0.01) showed the most significant P values. 13 metabolites have a causal relationship with HNSCC (P < 0.05). The proportion of the effect of Bilirubin degradation product, C16H18N2O5 (3) levels-mediated HLA DR + CD4 + AC on HNSCC was 7.17% (95% CI 1.04%-13.3%), while the proportion of the effect of Glutamine to alanine ratio-mediated EM CD8br AC on HNSCC was 8.88% (95% CI 2.2%-15.6%). Moreover, single-cell RNA-sequencing analysis confirmed that HLA DR + CD4 + AC and EM CD8br AC cells were commonly present in the HNSCC tumor microenvironment (TME). High expression of two immune phenotypes indicated a poorer prognosis. The results of differentially expressed genes (DEGs) analysis and functional enrichment indicated that Interferon-induced protein with tetratricopeptide repeats 1 (IFIT1)/Follicular dendritic cell secreted protein (FDCSP) and Keratin 19 type I (KRT19)/Kallikrein-related peptidase 5 (KLK5) may be responsible genes for two immune phenotypes, respectively. The results of quantitative real-time polymerase chain reaction (qRT-PCR) and survival analysis showed that FDCSP was significantly downregulated in HNSCC and could exert a protective effect. Collectively, our study clarified the causal relationship between immune cells, metabolites, and HNSCC, providing new insight for clinical diagnosis and treatment of HNSCC.

Comment on "The characterization of tumor immune microenvironment after neoadjuvant immunotherapy in head and neck squamous cell cancer using multiplex immunohistochemistry"

This study in Oral Oncology highlights how neoadjuvant immunotherapy reshapes the tumor immune microenvironment (TIME) in HNSCC, increasing CD8+ T cells and reducing immunosuppressive cells. Using multiplex immunohistochemistry, it offers crucial spatial insights into TIME dynamics, paving the way for biomarker development and personalized therapies. Future research should explore combining this approach with single-cell technologies to elucidate functional immune states, enhancing our understanding of therapeutic responses and informing novel combinatorial treatment strategies.

Targeting novel regulated cell death: disulfidptosis in cancer immunotherapy with immune checkpoint inhibitors

The battle against cancer has evolved over centuries, from the early stages of surgical resection to contemporary treatments including chemotherapy, radiation, targeted therapies, and immunotherapies. Despite significant advances in cancer treatment over recent decades, these therapies remain limited by various challenges. Immune checkpoint inhibitors (ICIs), a cornerstone of tumor immunotherapy, have emerged as one of the most promising advancements in cancer treatment. Although ICIs, such as CTLA-4 and PD-1/PD-L1 inhibitors, have demonstrated clinical efficacy, their therapeutic impact remains suboptimal due to patient-specific variability and tumor immune resistance. Cell death is a fundamental process for maintaining tissue homeostasis and function. Recent research highlights that the combination of induced regulatory cell death (RCD) and ICIs can substantially enhance anti-tumor responses across multiple cancer types. In cells exhibiting high levels of recombinant solute carrier family 7 member 11 (SLC7A11) protein, glucose deprivation triggers a programmed cell death (PCD) pathway characterized by disulfide bond formation and REDOX (reduction-oxidation) reactions, termed "disulfidptosis." Studies suggest that disulfidptosis plays a critical role in the therapeutic efficacy of SLC7A11high cancers. Therefore, to investigate the potential synergy between disulfidptosis and ICIs, this study will explore the mechanisms of both processes in tumor progression, with the goal of enhancing the anti-tumor immune response of ICIs by targeting the intracellular disulfidptosis pathway.

New advances in the therapeutic strategy of head and neck squamous cell carcinoma: A review of latest therapies and cutting-edge research

Head and neck squamous cell carcinoma (HNSCC) is a common and aggressive malignancy with a poor prognosis, particularly when diagnosed at advanced stages. Despite progress in surgical, chemotherapeutic, and radiotherapeutic interventions, the five-year survival rate remains low due to high rates of recurrence and therapeutic resistance. This review explores recent advances in therapeutic strategies for HNSCC, focusing on targeted therapies, immunotherapy, and innovative drug delivery systems. Targeted therapies, such as EGFR inhibitors and PI3K/AKT/mTOR pathway inhibitors, offer promising options for overcoming HNSCC, though resistance challenges persist. Emerging treatments, including dual-target inhibitors and personalized therapeutic approaches, show potential in addressing these limitations. Immunotherapy, particularly PD-1/PD-L1 blockade, has achieved positive outcomes in a subset of patients, though overall response rates remain modest. Strategies aimed at enhancing immune responses, such as combination therapies and nanotechnology-based drug delivery systems, are actively being investigated to improve efficacy. This review also underscores the critical role of the tumor microenvironment and epithelial-mesenchymal transition (EMT) in HNSCC progression and therapeutic resistance. Novel approaches, including smart drug delivery systems utilizing nanotechnology and immune modulation, are opening new avenues for more personalized and effective treatments. Ongoing interdisciplinary research into molecular targets and advanced drug delivery techniques holds great promise for significantly improving patient outcomes in HNSCC.

Neoadjuvant immunotherapy and oncolytic virotherapy in HPV positive and HPV negative skin cancer: A comprehensive review

Skin cancer is the most common new cancer among Caucasians. This cancer has different types, of which non-melanoma skin cancer is the most common type. Various factors affect this disease, one of which is viral infections, including HPV. This virus plays an important role in skin cancer, especially cSCCs. There are various options for the treatment of skin cancer, and today special attention has been paid to treatments based on therapeutic goals, immunotherapy and combination therapy. In this study, we have investigated treatments based on immunotherapy and virotherapy and the effect of HPV virus on the effectiveness of these treatments in skin cancer. Treatments based on virotherapy are performed for a long time in combination with other common treatments such as radiotherapy and chemotherapy in order to have a greater effect and lower its side effects, which include: shortness of breath, tachycardia, lowering blood pressure in the patient. Also, the most important axis of immunotherapy is to focus on PD1-PDL1, despite abundant evidence on the importance of immunotherapy, many studies investigate the use of immunotherapy inhibitors in the adjuvant and neoadjuvant setting in various cancers. Also, previous findings show conflicting evidence of the effect of HPV status on the response to immunotherapy.

MiR-15a-5p Knockdown up-Regulated ABCB1 Expression and Abated HNSCC Progression via the NF-κB Signaling Pathway

BACKGROUND

The high invasion and heterogeneity of head and neck squamous cell carcinoma (HNSCC) commonly leads to poor clinical outcomes. Identification of reliable biomarkers for HNSCC is imperative.

METHODS

The targeted gene with the highest mutation was screened out in cBioPortal database, and the interactive microRNAs (miRNAs) were identified by miRNA-mRNA co-expression analysis. CCK-8 and transwell assays were used to explore the proliferative, migrative, and invasive behaviors of HNSCC cells. The dual-luciferase reporter assay and cell transfection experiment were conducted. The role of miR-15a-5p was investigated in the in vivo xenograft mouse model.

RESULTS

ATP binding cassette transporter 1 (ABCB1) had the highest mutation frequency and multiple mutation types in HNSCC, and the decreased ABCB1 was significantly related to better prognosis of HNSCC patients. MiR-15a-5p was a regulator for ABCB1, which was up-regulated after miR-15a-5p inhibition in vitro. Furthermore, the miR-15a-5p knockdown significantly suppressed HNSCC cell proliferation, migration, and invasion in vitro, and reduced the HNSCC tumor growth and migration capabilities in vivo, possibly through NF-κB signaling pathway.

CONCLUSION

Collectively, miR-15a-5p knockdown increased the ABCB1 level and abated the HNSCC progression via the NF-κB signaling pathway. ABCB1 and miR-15a-5p were underlying predictors for HNSCC therapeutic biomarkers.

Regulatory T cells in immune checkpoint blockade antitumor therapy

Regulatory T cells (Tregs), an essential component of the human immune system, are a heterogeneous group of T lymphocytes with the ability to suppress immune responses and maintain immune homeostasis. Recent evidence indicates that Tregs may impair antitumor immunity and facilitate cancer progression by weakening functions of effector T cells (Teffs). Consequently, targeting Tregs to eliminate them from tumor microenvironments to improve Teffs' activity could emerge as an effective strategy for cancer immunotherapy. This review outlines the biology of Tregs, detailing their origins, classification, and crucial markers. Our focus lies on the complex role of Tregs in cancer's development, progression and treatment, particularly on their suppressive role upon antitumor responses via multiple mechanisms. We delve into Tregs' involvement in immune checkpoint blockade (ICB) therapy, their dual effect on cancer immunotherapy and their potential biomarkers for ICB therapy effectiveness. We also summarize advances in the therapies that adjust Tregs to optimize ICB therapy, which may be crucial for devising innovative cancer treatment strategies.

EGFR-targeting oxygen-saturated nanophotosensitizers for orchestrating multifaceted antitumor responses by counteracting immunosuppressive milieu

High Epidermal growth factor receptor (EGFR) in Cutaneous Squamous Cell Carcinoma (cSCC) is associated with poor prognosis and advanced metastatic stages, severely impeding the efficacy of EGFR-targeting immunotherapy. This is commonly attributed to the combinatory outcomes of hypoxic tumor microenvironment (TME) and immunosuppressive effector cells together. Herein, a novel paradigm of EGFR-targeting oxygen-saturated nanophotosensitizers, designated as CHPFN-O2, has been specifically tailored to mitigate tumor hypoxia in EGFR-positive cSCC and achieve Cetuximab (CTX)-mediated immunotherapy (CIT). The conjugated CTX in CHPFN-O2 serves to initiate immune responses by recruiting Fc receptor (FcR)-expressing immune effector cells towards tumor cells, thereby eliciting antibody-dependent cellular phagocytosis (ADCP), antibody-dependent cellular trogocytosis (ADCT) and antibody-dependent cellular cytotoxicity (ADCC). Besides, CHPFN-O2 can engender a shift from a tumor-friendly to a tumor-hostile one through improved tumor oxygenation, contributing to oxygen-elevated photodynamic therapy (oxPDT). Notably, the combination of oxPDT and CIT eventually promotes T-cell-mediated antitumor activity and successfully inhibits the growth of EGFR-expressing cSCC with good safety profiles. This comprehensive oxPDT/CIT integration aims not only to enhance therapeutic efficacy against EGFRhigh cSCC but also to extend its applicability to other EGFRhigh malignancies, thus delineating a new avenue for the highly efficient synergistic treatment of EGFR-expressing malignancies.

Tertiary lymphoid structure-related score as a predictor for survival prognosis and immunotherapy response in head and neck squamous cell carcinoma

Background

Substantial studies reveal that tertiary lymphoid structure (TLS) correlate with prognosis and immunotherapy response in various types of cancers. However, the predictive value of TLS, the specific immune cell subtype within TLS and their anti-tumor mechanisms remain unclear.

Methods

Based on 23 TLS-related genes (TLSRGs), we utilized bioinformatics methods to construct a scoring system, named TLSscore. By integrating RNA and single-cell sequencing data, we assessed the utility of TLSscore in head and neck squamous cell carcinoma (HNSCC). Flow cytometric sorting was used to isolate specific T cells subtypes, in vivo and in vitro experiments were conducted to demonstrate its anti-tumor effects.

Results

The TLSscore model was constructed and specific TLSscore-genes were found to consistently align with the spatial location of TLS. TLSscore has proven to be a robust predictive model for predicting survival prognosis, immune cell infiltration, somatic mutation and immunotherapy response. Notably, a specific PD1+CXCL13+CD8+T cell subtype was identified within TLS. Both in vivo and in vitro experiments demonstrated that PD1+CXCL13+CD8+T cell might represent a functional cell subtype exerting anti-tumor effects during the process of immune surveillance.

Conclusions

Our study presents a predictive model for TLS, which can evaluate its presence and predicts survival prognosis and immunotherapy response in HNSSC patients. Additionally, we identify a specific subtype of T cells that might elucidate the mechanism of TLS function in anti-tumor activities. This T cell subtype holds the potential to be a prognostic marker and a target for adoptive cell therapy (ACT) in the future.

Metabolic and Aging Influence on Anticancer Immunity in Oral Cancer

The average age and obesity prevalence are increasing globally. Both aging and metabolic disease burden increase the risk of oral squamous cell carcinoma (OSCC) through profound effects on the immunological and metabolic characteristics within the OSCC tumor microenvironment. While the mechanisms that link aging and obesity to OSCC remain unclear, there is evidence that the antitumor responses are diminished in both conditions. Remarkably, however, immune checkpoint blockade, a form of cancer immunotherapy, remains intact despite the enhanced immunosuppressive tumor microenvironment in the context of either aging or obesity. Herein, we review the current knowledge of how aging and systemic metabolic changes affect antitumor immunity with an emphasis on the role of tumor-associated macrophages that greatly contribute to tumor immunosuppression. Key aspects discussed include the mechanisms of angiogenesis, cytokine release, phagocytosis attenuation, and immune cell recruitment during obesity and aging that create an immune-suppressive tumor microenvironment by recruitment and repolarization of tumor-associated macrophages. Through a deeper appreciation of these mechanisms, the development of novel therapeutic approaches to control OSCC will provide more refined management of the tumor microenvironment in the context of aging and obesity.

Head and neck cancer: pathogenesis and targeted therapy

Head and neck cancer (HNC) is a highly aggressive type of tumor characterized by delayed diagnosis, recurrence, metastasis, relapse, and drug resistance. The occurrence of HNC were associated with smoking, alcohol abuse (or both), human papillomavirus infection, and complex genetic and epigenetic predisposition. Currently, surgery and radiotherapy are the standard treatments for most patients with early-stage HNC. For recurrent or metastatic (R/M) HNC, the first-line treatment is platinum-based chemotherapy combined with the antiepidermal growth factor receptor drug cetuximab, when resurgery and radiation therapy are not an option. However, curing HNC remains challenging, especially in cases with metastasis. In this review, we summarize the pathogenesis of HNC, including genetic and epigenetic changes, abnormal signaling pathways, and immune regulation mechanisms, along with all potential therapeutic strategies such as molecular targeted therapy, immunotherapy, gene therapy, epigenetic modifications, and combination therapies. Recent preclinical and clinical studies that may offer therapeutic strategies for future research on HNC are also discussed. Additionally, new targets and treatment methods, including antibody-drug conjugates, photodynamic therapy, radionuclide therapy, and mRNA vaccines, have shown promising results in clinical trials, offering new prospects for the treatment of HNC.

NK cell based immunotherapy against oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC), a major subtype of head and neck cancers, presents significant challenges due to its aggressive feature and limited therapeutic efficacy of conventional treatments. In response to these challenges, Natural Killer (NK) cells, a vital component of the innate immune system, are being explored for their therapeutic potential in OSCC due to their inherent ability to target and eliminate cancer cells without prior sensitization. This review uniquely focuses on the evolving role of NK cells specifically in OSCC, incorporating recent advancements in CAR-NK cell engineering and personalized therapy approaches that have not been comprehensively covered in previous reviews. The mechanisms through which NK cells exert cytotoxic effects on tumor cells include direct killing through the engagement of natural cytotoxic receptors and antibody-dependent cellular cytotoxicity (ADCC), making them promising agents in cancer immunotherapy. Additionally, the article explores recent advancements in engineering NK cells to enhance their antitumor activity, such as the modification with chimeric antigen receptors (CARs) to target specific tumor antigens. Clinical implications of NK cell-based therapies, including the challenges of integrating these treatments with existing protocols and the potential for personalized therapy, are examined. The review highlights the promise of NK cell therapies in improving outcomes for OSCC patients and outlines future directions for research in this dynamic field of oncological immunotherapy.

A case of response to combination treatment with TSA-DC-CTL immunotherapy and osimertinib in EGFR mutated advanced lung adenocarcinoma

BACKGROUND

This study details a case of a patient with advanced lung adenocarcinoma harboring an exon 19 deletion in the EGFR gene.

METHOD

A 46-year-old female patient was diagnosed with stage IVb left lung adenocarcinoma, with multiple bone and lymph node metastases. Following the identification of tumor-specific antigen peptides, the patient received a combination treatment of immunotherapy (TSA-DC-CTL) and oral osimertinib. Peripheral blood circulating immune cells and circulating tumor cells (CTCs) were monitored before and after treatment. PET-CT and CT scans were used to assess the tumor response to treatment.

RESULTS

A significant increase in total lymphocyte percentage and decrease in the number of CTCs in the patient was observed. Imaging studies showed a notable reduction in tumor metastases.

CONCLUSION

This report demonstrates the safety and efficacy of TSA-DC-CTL cell immunotherapy combined with osimertinib in the treatment of a patient with advanced lung adenocarcinoma with an EGFR exon 19 deletions. This study describes a promising new treatment option for patients with advanced lung cancer with EGFR mutations.

The Role of Estrogen and Estrogen Receptors in Head and Neck Tumors

Head and neck squamous cell carcinoma (HNSCC) is the most common histological form of head and neck tumors (HNTs), which originate from the epithelium of the lips and oral cavity, pharynx, larynx, salivary glands, nasal cavity, and sinuses. The main risk factors include consumption of tobacco in all forms and alcohol, as well as infections with high-risk human papillomaviruses or the Epstein-Barr virus. Regardless of the etiological agent, the risk of developing different types of HNTs is from two to more than six times higher in males than in females. The reason for such disparities probably lies in a combination of both biological and psychosocial factors. Therefore, it is hypothesized that exposure to female sex hormones, primarily estrogen, provides women with protection against the formation and metastasis of HNTs. In this review, we synthesized available knowledge on the role of estrogen and estrogen receptors (ERs) in the development and progression of HNTs, with special emphasis on membrane ERs, which are much less studied. We can summarize that in addition to epidemiologic studies unequivocally pointing to the protective effect of estrogen in women, an increased expression of both nuclear ERs, ERα, and ERβ, and membrane ERs, ERα36, GPER1, and NaV1.2, was present in different types of HNSCC, for which anti-estrogens could be used as an effective therapeutic approach.

Enhanced Photodynamic Therapy Synergizing with Inhibition of Tumor Neutrophil Ferroptosis Boosts Anti-PD-1 Therapy of Gastric Cancer

For tumor treatment, the ultimate goal in tumor therapy is to eliminate the primary tumor, manage potential metastases, and trigger an antitumor immune response, resulting in the complete clearance of all malignant cells. Tumor microenvironment (TME) refers to the local biological environment of solid tumors and has increasingly become an attractive target for cancer therapy. Neutrophils within TME of gastric cancer (GC) spontaneously undergo ferroptosis, and this process releases oxidized lipids that limit T cell activity. Enhanced photodynamic therapy (PDT) mediated by di-iodinated IR780 (Icy7) significantly increases the production of reactive oxygen species (ROS). Meanwhile, neutrophil ferroptosis can be triggered by increased ROS generation in the TME. In this study, a liposome encapsulating both ferroptosis inhibitor Liproxstatin-1 and modified photosensitizer Icy7, denoted LLI, significantly inhibits tumor growth of GC. LLI internalizes into MFC cells to generate ROS causing immunogenic cell death (ICD). Simultaneously, liposome-deliver Liproxstatin-1 effectively inhibits the ferroptosis of tumor neutrophils. LLI-based immunogenic PDT and neutrophil-targeting immunotherapy synergistically boost the anti-PD-1 treatment to elicit potent TME and systemic antitumor immune response with abscopal effects. In conclusion, LLI holds great potential for GC immunotherapy.

A novel enemy of cancer: recent investigations into protozoan anti-tumor properties

Cancer remains a significant global health issue, despite advances in screening and treatment. While existing tumor treatment protocols such as surgery, chemotherapy, radiotherapy, targeted therapy, and immunotherapy have proven effective in enhancing the prognosis for some patients, these treatments do not benefit all patients. Consequently, certain types of cancer continue to exhibit a relatively low 5-year survival rate. Therefore, the pursuit of novel tumor intervention strategies may help improve the current effectiveness of tumor treatment. Over the past few decades, numerous species of protozoa and their components have exhibited anti-tumor potential via immune and non-immune mechanisms. This discovery introduces a new research direction for the development of new and effective cancer treatments. Through in vitro experiments and studies involving tumor-bearing mice, the anti-tumor ability of Toxoplasma gondii, Plasmodium, Trypanosoma cruzi, and other protozoa have unveiled diverse mechanisms by which protozoa combat cancer, demonstrating encouraging prospects for their application. In this review, we summarize the anti-tumor ability and anti-tumor mechanisms of various protozoa and explore the potential for their clinical development and application.

Multi-kinase compensation rescues EGFR knockout in a cell line model of head and neck squamous cell carcinoma

BACKGROUND

Head and neck squamous cell carcinoma (HNSCC) is a debilitating disease with poor survival rates. While the epidermal growth factor receptor (EGFR)-targeting antibody Cetuximab is approved for treatment, responses are limited and the molecular mechanisms driving resistance remain incompletely understood.

METHODS

To better understand how cells survive without EGFR activity, we developed an EGFR knockout derivative of the UM-SCC-92 cell line using CRISPR/Cas9 technology. We then characterized changes to the transcriptome with RNAseq and changes in response to kinase inhibitors with resazurin cell viability assays. Finally, we tested if inhibitors with activity in the EGFR knockout model also had synergistic activity in combination with EGFR inhibitors in either wild type UM-SCC-92 cells or a known Cetuximab-resistant model.

RESULTS

Functional and molecular analysis showed that knockout cells had decreased cell proliferation, upregulation of FGFR1 expression, and an enhanced mesenchymal phenotype. In fact, expression of common EMT genes including VIM, SNAIL1, ZEB1 and TWIST1 were all upregulated in the EGFR knockout. Surprisingly, EGFR knockout cells were resistant to FGFR inhibitor monotherapies, but sensitive to combinations of FGFR and either XIAP or IGF-1R inhibitors. Accordingly, both wild type UM-SCC-92 and Cetuximab-resistant UM-SCC-104 cells with were sensitive to combined inhibition of EGFR, FGFR and either XIAP or IGF-1R.

CONCLUSIONS

These data offer insights into EGFR inhibitor resistance and show that resistance to EGFR knockout likely occurs through a complex network of kinases. Future studies of cetuximab-resistant HNSCC tumors are warranted to determine if this EMT phenotype and/or multi-kinase resistance is observed in patients.

Reprogramming the lipid metabolism of dendritic cells in tumor immunomodulation and immunotherapy

Dendritic cells (DCs) are the most potent antigen-presenting cells in the human body. They detect and process environmental signals and communicate with T cells to bridge innate and adaptive immunity. Cell activation, function, and survival are closely associated with cellular metabolism. An increasing number of studies have revealed that lipid metabolism affects DC activation as well as innate and acquired immune responses. Combining lipid metabolic regulation with immunotherapy can strengthen the ability of antigen-presentation and T-cell activation of DCs, improve the existing anti-tumor therapy, and overcome the defects of DC-related therapies in the current stage, which has great potential in cancer therapy. This review summarizes the lipid metabolism of DCs under physiological conditions, analyzes the role of reprogramming the lipid metabolism of DCs in tumor immune regulation, and discusses potential immunotherapeutic strategies.