Hypoxia inhibits the iMo/cDC2/CD8+ TRMs immune axis in the tumor microenvironment of human esophageal cancer.

BACKGROUND: Esophageal cancer (ESCA) is a form of malignant tumor associated with chronic inflammation and immune dysregulation. However, the specific immune status and key mechanisms of immune regulation in this disease require further exploration. METHODS: To investigate the features of the human ESCA tumor immune microenvironment and its possible regulation, we performed mass cytometry by time of flight, single-cell RNA sequencing, multicolor fluorescence staining of tissue, and flow cytometry analyses on tumor and paracancerous tissue from treatment-naïve patients. RESULTS: We depicted the immune landscape of the ESCA and revealed that CD8+ (tissue-resident memory CD8+ T cells (CD8+ TRMs) were closely related to disease progression. We also revealed the heterogeneity of CD8+ TRMs in the ESCA tumor microenvironment (TME), which was associated with their differentiation and function. Moreover, the subset of CD8+ TRMs in tumor (called tTRMs) that expressed high levels of granzyme B and immune checkpoints was markedly decreased in the TME of advanced ESCA. We showed that tTRMs are tumor effector cells preactivated in the TME. We then demonstrated that conventional dendritic cells (cDC2s) derived from intermediate monocytes (iMos) are essential for maintaining the proliferation of CD8+ TRMs in the TME. Our preliminary study showed that hypoxia can promote the apoptosis of iMos and impede the maturation of cDC2s, which in turn reduces the proliferative capacity of CD8+ TRMs, thereby contributing to the progression of cancer. CONCLUSIONS: Our study revealed the essential antitumor roles of CD8+ TRMs and preliminarily explored the regulation of the iMo/cDC2/CD8+ TRM immune axis in the human ESCA TME.

Progress in second-line antibody therapies for advanced esophageal squamous cell carcinoma.

INTRODUCTION: The prognosis of advanced esophageal squamous cell carcinoma (ESCC) is poor. Although cytotoxic drugs have been widely used in advanced ESCC, several antibody agents have recently been reported to be effective. AREAS COVERED: Nivolumab and pembrolizumab are anti-PD-1 antibodies that improve immunosuppression by binding to programmed death-1 (PD-1), leading to an antitumor effect. Randomized phase III trials have found these immune checkpoint inhibitors (ICIs) to be effective as second-line treatment. ATTRACTION-3, which compared nivolumab monotherapy with taxane monotherapy in patients with previously treated advanced ESCC, reported prolonged overall survival in the nivolumab group. KEYNOTE-181 found that overall survival was longer in patients with PD-L1-positive ESCC who received second-line treatment with pembrolizumab than in those who received chemotherapy. Sym004 and amivantamab are antibodies that target the epidermal growth factor receptor and have demonstrated efficacy in the treatment of other tumors in recent phase I studies. Furthermore, clinical trials on antibody-drug conjugates such as enfortumab vedotin and DS-7300 for solid tumors are currently ongoing. EXPERT OPINION: The standard first-line treatments for patients with advanced ESCC contain ICIs. Therefore, drugs with different mechanisms of action that can overcome resistance to ICIs are needed as second-line or later-line treatments to improve clinical outcomes in these patients.

Prognostic value of genomic mutation signature associated with immune microenvironment in southern Chinese patients with esophageal squamous cell carcinoma.

The genomic landscape of esophageal squamous cell cancer (ESCC), as well as its impact on the regulation of immune microenvironment, is not well understood. Thus, tumor samples from 92 patients were collected from two centers and subjected to targeted-gene sequencing. We identified frequently mutated genes, including TP53, KMT2C, KMT2D, LRP1B, and FAT1. The most frequent mutation sites were ALOX12B (c.1565C > T), SLX4 (c.2786C > T), LRIG1 (c.746A > G), and SPEN (c.6915_6917del) (6.5%). Pathway analysis revealed dysregulation of cell cycle regulation, epigenetic regulation, PI3K/AKT signaling, and NOTCH signaling. A 17-mutated gene-related risk model was constructed using random survival forest analysis and showed significant prognostic value in both our cohort and the validation cohort. Based on the Estimation of Stromal and Immune cells in Malignant Tumor tissues using Expression (ESTIMATE) algorithm, the Tumor Immune Dysfunction and Exclusion (TIDE) algorithm, and the MCPcounter algorithm, we found that the risk score calculated by the risk model was significantly correlated with stimulatory immune checkpoints (TNFSF4, ITGB2, CXCL10, CXCL9, and BTN3A1; p < 0.05). Additionally, it was significantly associated with markers that are important in predicting response to immunotherapy (CD274, IFNG, and TAMM2; p < 0.05). Furthermore, the results of immunofluorescence double staining showed that patients with high risk scores had a significantly higher level of M2 macrophage than those with low risk scores (p < 0.05). In conclusion, our study provides insights into the genomic landscape of ESCC and highlights the prognostic value of a genomic mutation signature associated with the immune microenvironment in southern Chinese patients with ESCC.

ΔNp63-restricted viral mimicry response impedes cancer cell viability and remodels tumor microenvironment in esophageal squamous cell carcinoma.

Tumor protein p63 isoform ΔNp63 plays roles in the squamous epithelium and squamous cell carcinomas (SCCs), including esophageal SCC (ESCC). By integrating data from cell lines and our latest patient-derived organoid cultures, derived xenograft models, and clinical sample transcriptomic analyses, we identified a novel and robust oncogenic role of ΔNp63 in ESCC. We showed that ΔNp63 maintains the repression of cancer cell endogenous retrotransposon expression and cellular double-stranded RNA sensing. These subsequently lead to a restricted cancer cell viral mimicry response and suppressed induction of tumor-suppressive type I interferon (IFN-I) signaling through the regulations of Signal transducer and activator of transcription 1, Interferon regulatory factor 1, and cGAS-STING pathway. The cancer cell ΔNp63/IFN-I signaling axis affects both the cancer cell and tumor-infiltrating immune cell (TIIC) compartments. In cancer cells, depletion of ΔNp63 resulted in reduced cell viability. ΔNp63 expression is negatively associated with the anticancer responses to viral mimicry booster treatments targeting cancer cells. In the tumor microenvironment, cancer cell TP63 expression negatively correlates with multiple TIIC signatures in ESCC clinical samples. ΔNp63 depletion leads to increased cancer cell antigen presentation molecule expression and enhanced recruitment and reprogramming of tumor-infiltrating myeloid cells. Similar IFN-I signaling and TIIC signature association with ΔNp63 were also observed in lung SCC. These results support the potential application of ΔNp63 as a therapeutic target and a biomarker to guide candidate anticancer treatments exploring viral mimicry responses.

Thermosensitive gel-nano system against esophageal cancer via restoring p53 activity and boosting T-cell immunity.

In esophageal cancer (EC), clinical specimen testing has uncovered a significant increase in BTB and CNC homolog 1 (BACH1) expression and a shift towards an immunosuppressive environment, alongside a notable decrease in p53 protein expression. Therefore, therapeutic strategies focusing on BACH1 inhibition and p53 upregulation appear promising. Traditional oral treatments for EC lack precision and efficacy. Here, we propose a novel approach employing tumor-targeted nanoparticles (NPs) for drug delivery. However, the formation of a drug reservoir at the esophageal site, crucial for the sustained release of therapeutics, presents significant challenges in nano-delivery systems for EC treatment. To address this, we developed a thermosensitive hydrogel composed of F127 and tannic acid, serving as a vehicle for NP loading. These NPs, synthesized through the emulsion/volatization methods of mPEG-PLGA-PLL-cRGD, facilitate in situ drug delivery. Upon contacting esophageal tissue, the hydrogel transitions to a gel, adhering to the lining and enabling sustained release of encapsulated therapeutics. The formulation encompasses NPs laden with small interfering RNA targeting BACH1 (siBACH1) and the p53 activator PRIMA-1, creating a cohesive gel-nano system. Preliminary biological assessments demonstrate that this injectable, thermosensitive gel-nano system adheres effectively to esophageal tissue and targets EC cells. For better modeling clinical outcomes, a patient-derived organoid xenograft (PDOX) model was innovated, involving transplantation of EC-derived organoids into humanized mice, reconstructed with peripheral blood mononuclear cells (PBMCs). Post-treatment analysis showed substantial EC growth inhibition (89.51% tumor inhibition rate), significant BACH1 level reduction, restored anti-tumor immune responses, and pronounced tumor apoptosis. In summary, our study introduces a thermosensitive gel-nano system for EC treatment via restoring p53 activity and boosting T-cell immunity, with potential for clinical application.

ISG15/GRAIL1/CD3 axis influences survival of patients with esophageal adenocarcinoma.

Immunosuppression is a common feature of esophageal adenocarcinoma (EAC) and has been linked to poor overall survival (OS). We hypothesized that upstream factors might negatively influence CD3 levels and T cell activity, thus promoting immunosuppression and worse survival. We used clinical data and patient samples of those who progressed from Barrett's to dysplasia to EAC, investigated gene (RNA-Seq) and protein (tissue microarray) expression, and performed cell biology studies to delineate a pathway impacting CD3 protein stability that might influence EAC outcome. We showed that the loss of both CD3-ε expression and CD3+ T cell number correlated with worse OS in EAC. The gene related to anergy in lymphocytes isoform 1 (GRAIL1), which is the prominent isoform in EACs, degraded (ε, γ, δ) CD3s and inactivated T cells. In contrast, isoform 2 (GRAIL2), which is reduced in EACs, stabilized CD3s. Further, GRAIL1-mediated CD3 degradation was facilitated by interferon-stimulated gene 15 (ISG15), a ubiquitin-like protein. Consequently, the overexpression of a ligase-dead GRAIL1, ISG15 knockdown, or the overexpression of a conjugation-defective ISG15-leucine-arginine-glycine-glycine mutant could increase CD3 levels. Together, we identified an ISG15/GRAIL1/mutant p53 amplification loop negatively influencing CD3 levels and T cell activity, thus promoting immunosuppression in EAC.

An investigation of the clinical impact and therapeutic relevance of a DNA damage immune response (DDIR) signature in patients with advanced gastroesophageal adenocarcinoma.

BACKGROUND: An improved understanding of which gastroesophageal adenocarcinoma (GOA) patients respond to both chemotherapy and immune checkpoint inhibitors (ICI) is needed. We investigated the predictive role and underlying biology of a 44-gene DNA damage immune response (DDIR) signature in patients with advanced GOA. MATERIALS AND METHODS: Transcriptional profiling was carried out on pretreatment tissue from 252 GOA patients treated with platinum-based chemotherapy (three dose levels) within the randomized phase III GO2 trial. Cross-validation was carried out in two independent GOA cohorts with transcriptional profiling, immune cell immunohistochemistry and epidermal growth factor receptor (EGFR) fluorescent in situ hybridization (FISH) (n = 430). RESULTS: In the GO2 trial, DDIR-positive tumours had a greater radiological response (51.7% versus 28.5%, P = 0.022) and improved overall survival in a dose-dependent manner (P = 0.028). DDIR positivity was associated with a pretreatment inflamed tumour microenvironment (TME) and increased expression of biomarkers associated with ICI response such as CD274 (programmed death-ligand 1, PD-L1) and a microsatellite instability RNA signature. Consensus pathway analysis identified EGFR as a potential key determinant of the DDIR signature. EGFR amplification was associated with DDIR negativity and an immune cold TME. CONCLUSIONS: Our results indicate the importance of the GOA TME in chemotherapy response, its relationship to DNA damage repair and EGFR as a targetable driver of an immune cold TME. Chemotherapy-sensitive inflamed GOAs could benefit from ICI delivered in combination with standard chemotherapy. Combining EGFR inhibitors and ICIs warrants further investigation in patients with EGFR-amplified tumours.

The single cell immunogenomic landscape after neoadjuvant immunotherapy combined chemotherapy in esophageal squamous cell carcinoma.

Neoadjuvant immunotherapy represents promising strategy in the treatment of esophageal squamous cell carcinoma (ESCC). However, the mechanisms underlying its impact on treatment sensitivity or resistance remain a subject of controversy. In this study, we conducted single-cell RNA and T/B cell receptor (scTCR/scBCR) sequencing of CD45+ immune cells on samples from 10 patients who received neoadjuvant immunotherapy and chemotherapy. We also validated our findings using multiplexed immunofluorescence and analyzed bulk RNA-seq from other cohorts in public database. By integrating analysis of 87357 CD45+ cells, we found GZMK + effector memory T cells (Tem) were relatively enriched and CXCL13+ exhausted T cells (Tex) and regulator T cells (Treg) decreased among responders, indicating a persistent anti-tumor memory process. Additionally, the enhanced presence of BCR expansion and somatic hypermutation process within TNFRSF13B + memory B cells (Bmem) suggested their roles in antigen presentation. This was further corroborated by the evidence of the T-B co-stimulation pattern and CXCL13-CXCR5 axis. The complexity of myeloid cell heterogeneity was also particularly pronounced. The elevated expression of S100A7 in ESCC, as detected by bulk RNA-seq, was associated with an exhausted and immunosuppressive tumor microenvironment. In summary, this study has unveiled a potential regulatory network among immune cells and the clonal dynamics of their functions, and the mechanisms of exhaustion and memory conversion between GZMK + Tem and TNFRSF13B + Bmem from antigen presentation and co-stimulation perspectives during neoadjuvant PD-1 blockade treatment in ESCC.

Construction of a Novel Mitochondria-Associated Gene Model for Assessing ESCC Immune Microenvironment and Predicting Survival.

Esophageal squamous cell carcinoma (ESCC) is among the most common malignant tumors of the digestive tract, with the sixth highest fatality rate worldwide. The ESCC-related dataset, GSE20347, was downloaded from the Gene Expression Omnibus (GEO) database, and weighted gene co-expression network analysis was performed to identify genes that are highly correlated with ESCC. A total of 91 transcriptome expression profiles and their corresponding clinical information were obtained from The Cancer Genome Atlas database. A mitochondria-associated risk (MAR) model was constructed using the least absolute shrinkage and selection operator Cox regression analysis and validated using GSE161533. The tumor microenvironment and drug sensitivity were explored using the MAR model. Finally, in vitro experiments were performed to analyze the effects of hub genes on the proliferation and invasion abilities of ESCC cells. To confirm the predictive ability of the MAR model, we constructed a prognostic model and assessed its predictive accuracy. The MAR model revealed substantial differences in immune infiltration and tumor microenvironment characteristics between high- and low-risk populations and a substantial correlation between the risk scores and some common immunological checkpoints. AZD1332 and AZD7762 were more effective for patients in the low-risk group, whereas Entinostat, Nilotinib, Ruxolutinib, and Wnt.c59 were more effective for patients in the high-risk group. Knockdown of TYMS significantly inhibited the proliferation and invasive ability of ESCC cells in vitro. Overall, our MAR model provides stable and reliable results and may be used as a prognostic biomarker for personalized treatment of patients with ESCC.

Molecular Landscape and Clinical Implication of CCNE1-amplified Esophagogastric Cancer.

Cyclin E overexpression as a result of CCNE1 amplification is a critical driver of genomic instability in gastric cancer, but its clinical implication is largely unknown. Thus, we integrated genomic, transcriptomic, and immune profiling analysis of 7,083 esophagogastric tumors and investigated the impact of CCNE1 amplification on molecular features and treatment outcomes. We identified CCNE1 amplification in 6.2% of esophageal adenocarcinoma samples, 7.0% of esophagogastric junction carcinoma, 4.2% of gastric adenocarcinoma samples, and 0.8% of esophageal squamous cell carcinoma. Metastatic sites such as lymph node and liver showed an increased frequency of CCNE1 amplification relative to primary tumors. Consistent with a chromosomal instability phenotype, CCNE1 amplification was associated with decreased CDH1 mutation and increased TP53 mutation and ERBB2 amplification. We observed no differences in immune biomarkers such as PD-L1 expression and tumor mutational burden comparing CCNE1-amplified and nonamplified tumors, although CCNE1 amplification was associated with changes in immune populations such as decreased B cells and increased M1 macrophages from transcriptional analysis. Real-world survival analysis demonstrated that patients with CCNE1-amplified gastric cancer had worse survival after trastuzumab for HER2-positive tumors, but better survival after immunotherapy. These data suggest that CCNE1-amplified gastric cancer has a distinct molecular and immune profile with important therapeutic implications, and therefore further investigation of CCNE1 amplification as a predictive biomarker is warranted. SIGNIFICANCE: Advanced gastric cancer has a relatively dismal outcome with a 5-year overall survival of less than 10%. Furthermore, while comprehensive molecular analyses have established molecular subtypes within gastric cancers, biomarkers of clinical relevance in this cancer type are lacking. Overall, this study demonstrates that CCNE1 amplification is associated with a distinct molecular profile in gastric cancer and may impact response to therapy, including targeted therapy and/or immunotherapy.

To develop a prognostic model for neoadjuvant immunochemotherapy efficacy in esophageal squamous cell carcinoma by analyzing the immune microenvironment.

Objective: The choice of neoadjuvant therapy for esophageal squamous cell carcinoma (ESCC) is controversial. This study aims to provide a basis for clinical treatment selection by establishing a predictive model for the efficacy of neoadjuvant immunochemotherapy (NICT). Methods: A retrospective analysis of 30 patients was conducted, divided into Response and Non-response groups based on whether they achieved major pathological remission (MPR). Differences in genes and immune microenvironment between the two groups were analyzed through next-generation sequencing (NGS) and multiplex immunofluorescence (mIF). Variables most closely related to therapeutic efficacy were selected through LASSO regression and ROC curves to establish a predictive model. An additional 48 patients were prospectively collected as a validation set to verify the model's effectiveness. Results: NGS suggested seven differential genes (ATM, ATR, BIVM-ERCC5, MAP3K1, PRG, RBM10, and TSHR) between the two groups (P < 0.05). mIF indicated significant differences in the quantity and location of CD3+, PD-L1+, CD3+PD-L1+, CD4+PD-1+, CD4+LAG-3+, CD8+LAG-3+, LAG-3+ between the two groups before treatment (P < 0.05). Dynamic mIF analysis also indicated that CD3+, CD8+, and CD20+ all increased after treatment in both groups, with a more significant increase in CD8+ and CD20+ in the Response group (P < 0.05), and a more significant decrease in PD-L1+ (P < 0.05). The three variables most closely related to therapeutic efficacy were selected through LASSO regression and ROC curves: Tumor area PD-L1+ (AUC= 0.881), CD3+PD-L1+ (AUC= 0.833), and CD3+ (AUC= 0.826), and a predictive model was established. The model showed high performance in both the training set (AUC= 0.938) and the validation set (AUC= 0.832). Compared to the traditional CPS scoring criteria, the model showed significant improvements in accuracy (83.3% vs 70.8%), sensitivity (0.625 vs 0.312), and specificity (0.937 vs 0.906). Conclusion: NICT treatment may exert anti-tumor effects by enriching immune cells and activating exhausted T cells. Tumor area CD3+, PD-L1+, and CD3+PD-L1+ are closely related to therapeutic efficacy. The model containing these three variables can accurately predict treatment outcomes, providing a reliable basis for the selection of neoadjuvant treatment plans.

Immune cell patterns before and after neoadjuvant immune checkpoint blockade combined with chemoradiotherapy in locally advanced esophageal squamous cell carcinoma.

BACKGROUND: Neoadjuvant immune checkpoint blockade (ICB) combined with chemoradiotherapy offers high pathologic complete response (pCR) rate for patients with locally advanced esophageal squamous cell carcinomas (ESCC). But the dynamic tumor immune microenvironment modulated by such neoadjuvant therapy remains unclear. PATIENTS AND METHODS: A total of 41 patients with locally advanced ESCC were recruited. All patients received neoadjuvant toripalimab combined with concurrent chemoradiotherapy. Matched pre- and post-treatment tissues were obtained for fluorescent multiplex immunohistochemistry (mIHC) and IHC analyses. The densities and spatial distributions of immune cells were determined by HALO modules. The differences of immune cell patterns before and after neoadjuvant treatment were investigated. RESULTS: In the pre-treatment tissues, more stromal CD3 + FoxP3 + Tregs and CD86+/CD163 + macrophages were observed in patients with residual tumor existed in the resected lymph nodes (pN1), compared with patients with pCR. The majority of macrophages were distributed in close proximity to tumor nest in pN1 patients. In the post-treatment tissues, pCR patients had less CD86 + cell infiltration, whereas higher CD86 + cell density was significantly associated with higher tumor regression grades (TRG) in non-pCR patients. When comparing the paired pre- and post-treatment samples, heterogeneous therapy-associated immune cell patterns were found. Upon to the treatment, CD3 + T lymphocytes were slightly increased in pCR patients, but markedly decreased in non-pCR patients. In contrast, a noticeable increase and a less obvious decrease of CD86 + cell infiltration were respectively depicted in non-pCR and pCR patients. Furthermore, opposite trends of the treatment-induced alterations of CD8 + and CD15 + cell infiltrations were observed between pN0 and pN1 patients. CONCLUSIONS: Collectively, our data demonstrate a comprehensive picture of tumor immune landscape before and after neoadjuvant ICB combined with chemoradiotherapy in ESCC. The infiltration of CD86 + macrophage may serve as an unfavorable indicator for neoadjuvant toripalimab combined with chemoradiotherapy.

Construction of an immune-related prognostic model and potential drugs screening for esophageal cancer based on bioinformatics analyses and network pharmacology.

BACKGROUND: Esophageal cancer (ESCA) is a highly invasive malignant tumor with poor prognosis. This study aimed to discover a generalized and high-sensitivity immune prognostic signature that could stratify ESCA patients and predict their overall survival, and to discover potential therapeutic drugs by the connectivity map. METHODS: The key gene modules significantly related to clinical traits (survival time and state) of ESCA patients were selected by weighted gene coexpression network analysis (WCGNA), then the univariate and least absolute shrinkage and selection operator (LASSO) Cox regression analyses were used to construct a 15-immune-related gene prognostic signature. RESULTS: The immune-related risk model was related to clinical and pathologic factors and remained an effective independent prognostic factor. Enrichment analyses revealed that the differentially expressed genes (DEGs) of the high- and low-risk groups were associated with tumor cell proliferation and immune mechanisms. Based on the gathered data, a small molecule drug named perphenazine (PPZ) was elected. The pharmacological analysis indicates that PPZ could help in adjuvant therapy of ESCA through regulation of metabolic process and cellular proliferation, enhancement of immunologic functions, and inhibition of inflammatory reactions. Furthermore, molecular docking was performed to explore and verify the PPZ-core target interactions. CONCLUSION: We succeed in structuring the immune-related prognostic model, which could be used to distinguish and predict patients' survival outcome, and screening a small molecule drug named PPZ. Prospective studies also are needed to further validate its analytical accuracy for estimating prognoses and confirm the potential use of PPZ for treating ESCA.

Comparative Epigenetic Profiling Reveals Distinct Features of Mucosal Melanomas Associated with Immune Cell Infiltration and Their Clinical Implications.

Mucosal melanoma exhibits limited responsiveness to anti-PD-1 therapy. However, a subgroup of mucosal melanomas, particularly those situated at specific anatomic sites like primary malignant melanoma of the esophagus (PMME), display remarkable sensitivity to anti-PD-1 treatment. The underlying mechanisms driving this superior response and the DNA methylation patterns in mucosal melanoma have not been thoroughly investigated. We collected tumor samples from 50 patients with mucosal melanoma, including 31 PMME and 19 non-esophageal mucosal melanoma (NEMM). Targeted bisulfite sequencing was conducted to characterize the DNA methylation landscape of mucosal melanoma and explore the epigenetic profiling differences between PMME and NEMM. Bulk RNA sequencing and multiplex immunofluorescence staining were performed to confirm the impact of methylation on gene expression and immune microenvironment. Our analysis revealed distinct epigenetic signatures that distinguish mucosal melanomas of different origins. Notably, PMME exhibited distinct epigenetic profiling characterized by a global hypermethylation alteration compared with NEMM. The prognostic model based on the methylation scores of a 7-DMR panel could effectively predict the overall survival of patients with PMME and potentially serve as a prognostic factor. PMME displayed a substantial enrichment of immune-activating cells in contrast to NEMM. Furthermore, we observed hypermethylation of the TERT promoter in PMME, which correlated with heightened CD8+ T-cell infiltration, and patients with hypermethylated TERT were likely to have improved responses to immunotherapy. Our results indicated that PMME shows a distinct methylation landscape compared with NEMM, and the epigenetic status of TERT might be used to estimate prognosis and direct anti-PD-1 treatment for mucosal melanoma. SIGNIFICANCE: This study investigated the intricate epigenetic factor of mucosal melanomas contributed to the differential immune checkpoint inhibitor response, and found that PMME exhibited a global hypermethylation pattern and lower gene expression in comparison to NEMM. TERT hypermethylation may contribute to the favorable responses observed in patients with mucosal melanoma undergoing immunotherapy.

Molecular and immunological characteristics of postoperative relapse in lymph node-positive esophageal squamous cell cancer.

BACKGROUND: The molecular and immunological characteristics of primary tumors and positive lymph nodes in esophageal squamous cell carcinoma (ESCC) are unknown and the relationship with recurrence is unclear, which this study attempted to explore. METHODS: A total of 30 ESCC patients with lymph node positive (IIB-IVA) were enrolled. Among them, primary tumor and lymph node specimens were collected from each patient, and subjected to 551-tumor-targeted DNA sequencing and 289-immuno-oncology RNA panel sequencing to identify the different molecular basis and immunological features, respectively. RESULTS: The primary tumors exhibited a higher mutation burden than lymph nodes (p < 0.001). One-year recurrent ESCC exhibited a higher Mucin16 (MUC16) mutation rate (p = 0.038), as well as univariate and multivariate analysis revealed that MUC16 mutation is independent genetic factor associated with reduced relapse-free survival (univariate, HR: 5.39, 95% CI: 1.67-17.4, p = 0.005; multivariate, HR: 7.36, 95% CI: 1.79-30.23, p = 0.006). Transcriptomic results showed non-relapse group had higher cytolytic activity (CYT) score (p = 0.025), and was enriched in the IFN-α pathway (p = 0.036), while those in the relapsed group were enriched in the TNF-α/NF-κB (p = 0.001) and PI3K/Akt pathway (p = 0.014). CONCLUSION: The difference in molecular characteristics between primary lesions and lymph nodes may be the cause of the inconsistent clinical outcomes. Mutations of MUC16 and poor immune infiltration are associated with rapid relapse of nodes-positive ESCC.

The immunoglobulin superfamily ligand B7H6 subjects T cell responses to NK cell surveillance.

Understanding the mechanisms that regulate T cell immunity is critical for the development of effective therapies for diseases associated with T cell dysfunction, including autoimmune diseases, chronic infections, and cancer. Co-inhibitory "checkpoint molecules," such as programmed cell death protein-1, balance excessive or prolonged immune activation by T cell-intrinsic signaling. Here, by screening for mediators of natural killer (NK) cell recognition on T cells, we identified the immunoglobulin superfamily ligand B7H6 to be highly expressed by activated T cells, including patient-infused CD19-targeting chimeric antigen receptor (CAR) T cells. Unlike other checkpoint molecules, B7H6 mediated NKp30-dependent recognition and subsequent cytolysis of activated T cells by NK cells. B7H6+ T cells were prevalent in the tissue and blood of several diseases, and their abundance in tumor tissue positively correlated with clinical response in a cohort of patients with immune checkpoint inhibitor-treated esophageal cancer. In humanized mouse models, NK cell surveillance via B7H6 limited the persistence and antitumor activity of CAR T cells, and its genetic deletion enhanced T cell proliferation and persistence. Together, we provide evidence of B7H6 protein expression by activated T cells and suggest the B7H6-NKp30 axis as a therapeutically actionable NK cell-dependent immune checkpoint that regulates human T cell function.

Immunotherapy for esophageal cancer: Where are we now and where can we go.

Immune checkpoint inhibitor therapy has dramatically improved patient prognosis, and thereby transformed the treatment in various cancer types including esophageal squamous cell carcinoma (ESCC) in the past decade. Monoclonal antibodies that selectively inhibit programmed cell death-1 (PD-1) activity has now become standard of care in the treatment of ESCC in metastatic settings, and has a high expectation to provide clinical benefit during perioperative period. Further, anti-cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) monoclonal antibody has also been approved in the treatment of recurrent/metastatic ESCC in combination with anti-PD-1 antibody. Well understanding of the existing evidence of immune-based treatments for ESCC, as well as recent clinical trials on various combinations with chemotherapy for different clinical settings including neoadjuvant, adjuvant, and metastatic diseases, may provide future prospects of ESCC treatment for better patient outcomes.

Mechanisms of tumor immunosuppressive microenvironment formation in esophageal cancer.

As a highly invasive malignancy, esophageal cancer (EC) is a global health issue, and was the eighth most prevalent cancer and the sixth leading cause of cancer-related death worldwide in 2020. Due to its highly immunogenic nature, emer-ging immunotherapy approaches, such as immune checkpoint blockade, have demonstrated promising efficacy in treating EC; however, certain limitations and challenges still exist. In addition, tumors may exhibit primary or acquired resistance to immunotherapy in the tumor immune microenvironment (TIME); thus, understanding the TIME is urgent and crucial, especially given the im-portance of an immunosuppressive microenvironment in tumor progression. The aim of this review was to better elucidate the mechanisms of the suppressive TIME, including cell infiltration, immune cell subsets, cytokines and signaling pathways in the tumor microenvironment of EC patients, as well as the downregulated expression of major histocompatibility complex molecules in tumor cells, to obtain a better understanding of the differences in EC patient responses to immunotherapeutic strategies and accurately predict the efficacy of immunotherapies. Therefore, personalized treatments could be developed to maximize the advantages of immunotherapy.

CD276 regulates the immune escape of esophageal squamous cell carcinoma through CXCL1-CXCR2 induced NETs.

BACKGROUND: CD276 (B7-H3), a pivotal immune checkpoint, facilitates tumorigenicity, invasiveness, and metastasis by escaping immune surveillance in a variety of tumors; however, the underlying mechanisms facilitating immune escape in esophageal squamous cell carcinoma (ESCC) remain enigmatic. METHODS: We investigated the expression of CD276 in ESCC tissues from patients by using immunohistochemistry (IHC) assays. In vivo, we established a 4-nitroquinoline 1-oxide (4NQO)-induced CD276 knockout (CD276wKO) and K14cre; CD276 conditional knockout (CD276cKO) mouse model of ESCC to study the functional role of CD276 in ESCC. Furthermore, we used the 4NQO-induced mouse model to evaluate the effects of anti-CXCL1 antibodies, anti-Ly6G antibodies, anti-NK1.1 antibodies, and GSK484 inhibitors on tumor growth. Moreover, IHC, flow cytometry, and immunofluorescence techniques were employed to measure immune cell proportions in ESCC. In addition, we conducted single-cell RNA sequencing analysis to examine the alterations in tumor microenvironment following CD276 depletion. RESULTS: In this study, we elucidate that CD276 is markedly upregulated in ESCC, correlating with poor prognosis. In vivo, our results indicate that depletion of CD276 inhibits tumorigenesis and progression of ESCC. Furthermore, conditional knockout of CD276 in epithelial cells engenders a significant downregulation of CXCL1, consequently reducing the formation of neutrophil extracellular trap networks (NETs) via the CXCL1-CXCR2 signaling axis, while simultaneously augmenting natural killer (NK) cells. In addition, overexpression of CD276 promotes tumorigenesis via increasing NETs' formation and reducing NK cells in vivo. CONCLUSIONS: This study successfully elucidates the functional role of CD276 in ESCC. Our comprehensive analysis uncovers the significant role of CD276 in modulating immune surveillance mechanisms in ESCC, thereby suggesting that targeting CD276 might serve as a potential therapeutic approach for ESCC treatment.

Association of immune cells and the risk of esophageal cancer: A Mendelian randomization study in a East Asian population.

Immunotherapy has been used in esophageal cancer (EC), but the causal relationship between EC and immune cells is not clear. Although the cellular phenotype has been reported as a biomarker for immunotherapy, the biomarker studies for immunotherapy in EC still face great challenges. Comprehensive 2-sample Mendelian randomization (MR) analysis was performed to determine the causal association between immune cell signatures and EC in this study. Based on publicly available genetic data, we explored causal associations between 731 immune cell signatures and EC risk. EC had no statistically significant effect on immunophenotypes. Nine immunophenotype types were positively associated with the risk of EC: CD20-%B cell, CD20% lymphocytes, CD25 on IgD- CD27-, CD25 on IgD+ CD24+, CD27 on IgD+ CD24+, CD28+ CD45RA- CD8br AC, CD3 on TD CD8br, IgD-CD38dim%B cells, and Mo MDSC AC. In addition, a total of 15 immunophenotypes were identified as causally associated with EC. IgD+ CD38- %B cell, IgD- CD24- %lymphocyte, CD19 on IgD- CD38dim, CD20 on IgD+ CD24+, CD62L-myeloid DC AC, CD4+ AC, Lymphocyte %leukocyte, CD3 on HLA-DR+ T cell, CD3 on CD45RA- CD4+, HVEM on naive CD4+ AC, HVEM on CD45RA- CD4+, CD4 on TD CD4+, CD4 on CD4 Treg, and CD4 on CD39+ resting Treg, and CD4 on activated & secreting Treg. Our study has demonstrated the close connection between immune cells and EC by genetic means, thus providing guidance for future clinical research.