SPINK5 inhibits esophageal squamous cell carcinoma metastasis via immune activity.

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is a predominant subtype of esophageal cancer with relatively high mortality worldwide. Serine peptidase inhibitor Kazal-type 5 (SPINK5) is reported to be downregulated in ESCC. However, its explicit role in ESCC remains further investigation. METHODS: The tumor tissues and adjacent non-cancerous tissues were obtained from 196 patients with ESCC for the determination of SPINK5 mRNA levels. Additionally, the relationship between SPINK5 mRNA levels and clinicopathological features of ESCC patients was explored. The effects of SPINK5 on the invasion and migration of ESCC cells were assessed using Transwell assays. Furthermore, SPINK5 mRNA and LEKTI protein were measured in ESCC cell lines after treatment with poly (I:C), lipopolysaccharide (LPS) or unmethylated CpG DNA. Moreover, the correlation between expression of SPINK5 and nuclear factor-kappa B (NF-κB) signaling pathway-related genes was analyzed in the TCGA-ESCC cohort, and the effects of SPINK5 on NF-κB transcription was analyzed using a luciferase reporter gene assay. Finally, the correlations between SPINK5 and infiltration of immune cells, immune scores, stromal scores and ESTIMATE (i.e., Estimation of STromal and Immune cells in MAlignant Tumor tissues using Expression data) scores were explored. RESULTS: SPINK5 mRNA levels were downregulated in tumor tissues, which was significantly correlated with higher lymph node metastases. Overexpressed SPINK5 inhibited cell invasion and migration in ESCC cell lines. Mechanistically, LPS-induced activation of Toll-like receptor 4 (TLR4) decreased SPINK5 mRNA and LEKTI in KYSE150 and KYSE70 cells. Spearman correlation analysis revealed that SPINK5 mRNA was significantly negatively correlated with a total of seven NF-κB signaling pathway-related genes in TCGA-ESCC patients. Moreover, downregulation of SPINK5 increased and upregulation of SPINK5 decreased the activity of the NF-κB promoter in HEK293T cells. Finally, immune cells infiltration analysis revealed that SPINK5 was significantly correlated with the infiltration of various immune cells, stromal scores, immune scores and ESTIMATE scores. CONCLUSIONS: SPINK5 plays critical roles in the TLR4/NF-κB pathway and immune cells infiltration, which might contribute to the ESCC metastasis. The findings of the present study may provide a promising biomarker for the diagnosis and treatment of esophageal squamous cell carcinoma.

Immunotherapy Mechanism of Esophageal Squamous Cell Carcinoma with the Effect of STK11/AMPK Signaling Pathway.

This study was aimed at exploring the mechanism of serine threonine protein kinase 11 (STK11)/Adenosine 5'-monophosphate-activated protein kinase (AMPK) signaling pathway after immunotherapy for esophageal squamous cell carcinoma (ESCC), providing basic information for the clinical treatment of ESCC. In this study, tissue specimens from 100 patients with ESCC who underwent surgical treatment in Taizhou People's Hospital (group A) and 20 patients with recurrent or metastatic ESCC who received second-line immunotherapy (group B) were collected. The real-time fluorescent quantitative polymerase chain reaction (PCR) (RT-qPCR) technology was used to detect the expression levels of STK11, interferon-γ (IFN-γ), interleukin 6 (IL-6), and vascular endothelial growth factor (VEGF) in the tissues. The immunohistochemical staining was used to detect the positive expression levels (PELs) of STK11 and AMPKα in the tissues, and immunofluorescence staining was used to detect the PELs Teff cells (CD3 and CD8), Treg cells (CD4 and FOXP3), and neutrophils (CD68 and CD163). RT-qPCR results showed that the expression levels of STK11 and IFN-γ in group A were obviously lower, and those of IL-6 and VEGF were much higher in contrast to group B (P < 0.05). The results of immunohistochemical staining showed that the number of STK11- and AMPKα-positive staining cells in group A was dramatically less than that in group B (P <0.05). The results of immunofluorescence staining revealed that the number of positive staining cells for Teff cells, Treg cells, and neutrophils in group A was also less dramatically than that in group B (P <0.05). In summary, immunotherapy can play a therapeutic effect on ESCC by regulating STK11/AMPK pathway and immune cell infiltration.

Efficient targeting of NY-ESO-1 tumor antigen to human cDC1s by lymphotactin results in cross-presentation and antigen-specific T cell expansion.

BACKGROUND: Type 1 conventional dendritic cells (cDC1s) are characterized by their ability to induce potent CD8+ T cell responses. In efforts to generate novel vaccination strategies, notably against cancer, human cDC1s emerge as an ideal target to deliver antigens. cDC1s uniquely express XCR1, a seven transmembrane G protein-coupled receptor. Due to its restricted expression and endocytic nature, XCR1 represents an attractive receptor to mediate antigen-delivery to human cDC1s. METHODS: To explore tumor antigen delivery to human cDC1s, we used an engineered version of XCR1-binding lymphotactin (XCL1), XCL1(CC3). Site-specific sortase-mediated transpeptidation was performed to conjugate XCL1(CC3) to an analog of the HLA-A*02:01 epitope of the cancer testis antigen New York Esophageal Squamous Cell Carcinoma-1 (NY-ESO-1). While poor epitope solubility prevented isolation of stable XCL1-antigen conjugates, incorporation of a single polyethylene glycol (PEG) chain upstream of the epitope-containing peptide enabled generation of soluble XCL1(CC3)-antigen fusion constructs. Binding and chemotactic characteristics of the XCL1-antigen conjugate, as well as its ability to induce antigen-specific CD8+ T cell activation by cDC1s, was assessed. RESULTS: PEGylated XCL1(CC3)-antigen conjugates retained binding to XCR1, and induced cDC1 chemoattraction in vitro. The model epitope was efficiently cross-presented by human cDC1s to activate NY-ESO-1-specific CD8+ T cells. Importantly, vaccine activity was increased by targeting XCR1 at the surface of cDC1s. CONCLUSION: Our results present a novel strategy for the generation of targeted vaccines fused to insoluble antigens. Moreover, our data emphasize the potential of targeting XCR1 at the surface of primary human cDC1s to induce potent CD8+ T cell responses.

Neutrophil-to-Lymphocyte Ratio as a Predictor of Postoperative Recurrence and Prognosis in Oesophageal Squamous Cell Carcinoma.

BACKGROUND: Trimodal therapy is frequently used for patients with locally advanced, resectable oesophageal cancer. However, it does not provide a satisfactory prognosis. The neutrophil-to-lymphocyte ratio (NLR) is an important indicator of patients' inflammatory and immune statuses. We investigated the prognostic role of NLR values obtained at different treatment stages in patients with oesophageal squamous cell carcinoma. PATIENTS AND METHODS: We evaluated the correlation between NLR values or their change and prognosis at each treatment point (before chemoradiotherapy; before surgery; and at 14 days, and 1 and 2 months postoperatively) in 163 patients with oesophageal squamous cell carcinoma who underwent oesophagectomy after neoadjuvant chemoradiotherapy from April 2003 to August 2018. The outcomes studied were overall (OS) and relapse-free (RFS) survival. RESULTS: The NLR at 1 month postoperatively showed the strongest correlation with prognosis, with an optimal cut-off value of 4.5 (area under the curve=0.7878; 95% confidence interval=0.70-0.85; p<0.0001). Univariate and multivariate analyses showed that NLR ≥4.5 was a significant factor for both RFS (hazard ratio=4.44, 95% confidence interval=2.69-7.34) and OS (hazard ratio=3.88, 95% confidence interval=2.38-6.32). Furthermore, NLR significantly stratified patients for the RFS and OS regardless of the pathological response (complete/non-complete response) and postoperative complications (Clavien-Dindo grade

Immuno-oncological role of 20S proteasome alpha-subunit 3 in aggravating the progression of esophageal squamous cell carcinoma.

PSMA3, a member of the proteasome subunit, has been shown to play a major player in protein degradation. Reportedly, PSMA3 functions as a negative regulator in various cancers including colon, pancreatic and gastric cancers. However, the contributions of PSMA3 to the progression of esophageal squamous cell carcinoma (ESCC) and the underlying mechanism remain unclear. Therefore, in this study, we investigated whether PSMA3 is involved in ESCC progression and the potential underlying mechanism. The results revealed that PSMA3 was highly expressed in the ESCC tumor tissues and functioned as a negative indicator according to the data from The Cancer Genome Atlas (TCGA)/Gene Expression Omnibus (GEO) datasets and clinical patients' samples. Pathway enrichment analysis showed that PSMA3 was closely correlated with ESCC cancer stemness and the inflammatory response; however, this correlation was absent after knockdown of PSMA3 in vitro. We further demonstrated that PSMA3 suppressed CD8+ T-cells infiltration depending on the C-C motif chemokine ligand 3 (CCL3)/C-C motif chemokine receptor 5 (CCR5) axis. Collectively, these results demonstrate the role of PSMA3 in ESCC cancer stemness and the negative regulation of CD8 T-cells infiltration mediated by PSMA3. The results of this study may provide a potential target for the immuno-oncology effect of PSMA3 in ESCC therapy.

Integrated single-cell transcriptome analysis reveals heterogeneity of esophageal squamous cell carcinoma microenvironment.

The tumor microenvironment is a highly complex ecosystem of diverse cell types, which shape cancer biology and impact the responsiveness to therapy. Here, we analyze the microenvironment of esophageal squamous cell carcinoma (ESCC) using single-cell transcriptome sequencing in 62,161 cells from blood, adjacent nonmalignant and matched tumor samples from 11 ESCC patients. We uncover heterogeneity in most cell types of the ESCC stroma, particularly in the fibroblast and immune cell compartments. We identify a tumor-specific subset of CST1+ myofibroblasts with prognostic values and potential biological significance. CST1+ myofibroblasts are also highly tumor-specific in other cancer types. Additionally, a subset of antigen-presenting fibroblasts is revealed and validated. Analyses of myeloid and T lymphoid lineages highlight the immunosuppressive nature of the ESCC microenvironment, and identify cancer-specific expression of immune checkpoint inhibitors. This work establishes a rich resource of stromal cell types of the ESCC microenvironment for further understanding of ESCC biology.

Construction and Validation of an Immune-Related Gene Prognostic Index for Esophageal Squamous Cell Carcinoma.

Immune checkpoint inhibitor (ICI) therapy may benefit patients with advanced esophageal squamous cell carcinoma (ESCC); however, novel biomarkers are needed to help predict the response of patients to treatment. Differentially expressed immune-related genes within The Cancer Genome Atlas ESCC dataset were selected using the weighted gene coexpression network and lasso Cox regression analyses. Based on these data, an immune-related gene prognostic index (IRGPI) was constructed. The molecular characteristics of the different IRGPI subgroups were assessed using mutation information and gene set enrichment analysis. Differences in immune cell infiltration and the response to ICI therapy and other drugs were also analyzed. Additionally, tumor and adjacent control tissues were collected from six patients with ESCC and the expression of these genes was verified using real-time quantitative polymerase chain reaction. IRGPI was designed based on CLDN1, HCAR3, FNBP1L, and BRCA2, the expression of which was confirmed in ESCC samples. The prognosis of patients in the high-IRGPI group was poor, as verified using publicly available expression data. KMT2D mutations were more common in the high-IRGPI group. Enrichment analysis revealed an active immune response, and immune infiltration assessment showed that the high-IRGPI group had an increased infiltration degree of CD8 T cells, which contributed to the improved response to ICI treatment. Collectively, these data demonstrate that IRGPI is a robust biomarker for predicting the prognosis and response to therapy of patients with ESCC.

Epigenetically associated CCL20 upregulation correlates with esophageal cancer progression and immune disorder.

Chemokines have distinct effects on tumor progression by affecting cancer immunity and tumorigenesis. However, the characteristic chemokine profiles and their roles in immune cell recruitment and cancer cell biology are not entirely understood in esophageal cancer. Here, we scrutinized chemokine's expression profiles in independent esophageal cancer cohorts and identified the elevated CCL20 as a risk factor to predict patients' prognosis regardless of histology subtypes. Enhanced CCL20 expression was also associated with the acquisition of metastatic potential. Mechanistically, the upregulation of CCL20 in tumor cells was associated with promoter hypomethylation. Furthermore, by analyzing single-cell RNA sequencing data of a mouse model mimicking human ESCC development, we observed an imbalance among CD4+ T subtypes in the tumor microenvironment, namely Ccr6+ Th17 and Treg cells infiltration alongside the elevated Ccl20 expression in abnormal epithelial cells during the tumorigenic process. Together, these results reveal that hypomethylation-induced CCL20 promotes esophageal cancer progression and immune disorder. Targeting CCL20 might be a promising therapeutic approach in esophageal cancer.

Ursolic Acid Accelerates Paclitaxel-Induced Cell Death in Esophageal Cancer Cells by Suppressing Akt/FOXM1 Signaling Cascade.

Ursolic acid (UA), a pentacyclic triterpenoid extracted from various plants, inhibits cell growth, metastasis, and tumorigenesis in various cancers. Chemotherapy resistance and the side effects of paclitaxel (PTX), a traditional chemotherapy reagent, have limited the curative effect of PTX in esophageal cancer. In this study, we investigate whether UA promotes the anti-tumor effect of PTX and explore the underlying mechanism of their combined effect in esophageal squamous cell carcinoma (ESCC). Combination treatment with UA and PTX inhibited cell proliferation and cell growth more effectively than either treatment alone by inducing more significant apoptosis, as indicated by increased sub-G1 phase distribution and protein levels of cleaved-PARP and cleaved caspase-9. Similar to the cell growth suppressive effect, the combination of UA and PTX significantly inhibited cell migration by targeting uPA, MMP-9, and E-cadherin in ESCC cells. In addition, combination treatment with UA and PTX significantly activated p-GSK-3ß and suppressed the activation of Akt and FOXM1 in ESCC cells. Those effects were enhanced by the Akt inhibitor LY2940002 and inverted by the Akt agonist SC79. In an in vivo evaluation of a murine xenograft model of esophageal cancer, combination treatment with UA and PTX suppressed tumor growth significantly better than UA or PTX treatment alone. Thus, UA effectively potentiates the anti-tumor efficacy of PTX by targeting the Akt/FOXM1 cascade since combination treatment shows significantly more anti-tumor potential than PTX alone both in vitro and in vivo. Combination treatment with UA and PTX could be a new strategy for curing esophageal cancer patients.

The Functionalities and Clinical Significance of Tumor-Infiltrating Immune Cells in Esophageal Squamous Cell Carcinoma.

Tumor-infiltrating immune cells have been implicated in the tumorigenesis and progression of esophageal squamous cell carcinoma (ESCC). However, the functionalities and clinical significance of immune cells remain largely unveiled. In this study, the gene expression data from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) were extracted. The relative infiltrating levels were estimated by single-sample gene set enrichment analysis. Some cytotoxic immune cells were attenuated, and resting cytotoxic immune cells were accumulated in ESCC. Remarkably, we also observed that infiltrating levels of macrophage M2 and resting natural killer (NK) cells were increased in nonresponders of CRT, and T cells that had anticancer activities such as activated memory CD4 and T helper 2 (Th2) cells were significantly reduced in ESCC tissues of the nonresponders. Moreover, the high infiltrations of the resting natural killer (NK) and dendritic cell (DC) were observed to result in a shorter overall survival in ESCC. Consistently, high expression of immune checkpoint genes, CTLA4 and HAVCR2, was associated with poor prognosis. Furthermore, STAT5B, a key transcription factor, as well as its target genes, involved in the regulation of T cells, was significantly downregulated in ESCC, especially subgroup I, indicating that downregulation of STAT5B might be associated with reduced T cell-mediated anticancer activity. In conclusion, the present study significantly improved our understanding of the regulatory roles of immune cells in ESCC.

Dissecting esophageal squamous-cell carcinoma ecosystem by single-cell transcriptomic analysis.

Esophageal squamous-cell carcinoma (ESCC), one of the most prevalent and lethal malignant disease, has a complex but unknown tumor ecosystem. Here, we investigate the composition of ESCC tumors based on 208,659 single-cell transcriptomes derived from 60 individuals. We identify 8 common expression programs from malignant epithelial cells and discover 42 cell types, including 26 immune cell and 16 nonimmune stromal cell subtypes in the tumor microenvironment (TME), and analyse the interactions between cancer cells and other cells and the interactions among different cell types in the TME. Moreover, we link the cancer cell transcriptomes to the somatic mutations and identify several markers significantly associated with patients' survival, which may be relevant to precision care of ESCC patients. These results reveal the immunosuppressive status in the ESCC TME and further our understanding of ESCC.

Immunotherapy in Patients With Locally Advanced Esophageal Carcinoma: ASCO Treatment of Locally Advanced Esophageal Carcinoma Guideline Rapid Recommendation Update.

ASCO Rapid Recommendations Updates highlight revisions to select ASCO guideline recommendations as a response to the emergence of new and practice-changing data. The rapid updates are supported by an evidence review and follow the guideline development processes outlined in the ASCO Guideline Methodology Manual. The goal of these articles is to disseminate updated recommendations, in a timely manner, to better inform health practitioners and the public on the best available cancer care options.

Integrated bioinformatics analysis of differentially expressed genes and immune cell infiltration characteristics in Esophageal Squamous cell carcinoma.

Esophageal squamous cell carcinoma (ESCC) is a life-threatening thoracic tumor with a poor prognosis. The role of molecular alterations and the immune microenvironment in ESCC development has not been fully elucidated. The present study aimed to elucidate key candidate genes and immune cell infiltration characteristics in ESCC by integrated bioinformatics analysis. Nine gene expression datasets from the Gene Expression Omnibus (GEO) database were analysed to identify robust differentially expressed genes (DEGs) using the robust rank aggregation (RRA) algorithm. Functional enrichment analyses showed that the 152 robust DEGs are involved in multiple processes in the tumor microenvironment (TME). Immune cell infiltration analysis based on the 9 normalized GEO microarray datasets was conducted with the CIBERSORT algorithm. The changes in macrophages between ESCC and normal tissues were particularly obvious. In ESCC tissues, M0 and M1 macrophages were increased dramatically, while M2 macrophages were decreased. A robust DEG-based protein-protein interaction (PPI) network was used for hub gene selection with the CytoHubba plugin in Cytoscape. Nine hub genes (CDA, CXCL1, IGFBP3, MMP3, MMP11, PLAU, SERPINE1, SPP1 and VCAN) had high diagnostic efficiency for ESCC according to receiver operating characteristic (ROC) curve analysis. The expression of all hub genes except MMP3 and PLAU was significantly related to macrophage infiltration. Univariate and multivariate regression analyses showed that a 7-gene signature constructed from the robust DEGs was useful for predicting ESCC prognosis. Our results might facilitate the exploration of potential targeted TME therapies and prognostic evaluation in ESCC.

Clinical Significance of Fusobacterium nucleatum Infection and Regulatory T Cell Enrichment in Esophageal Squamous Cell Carcinoma.

A variety of pathogenic microorganisms promote tumor occurrence and development through long-term colonization in the body. Fusobacterium nucleatum (F. nucleatum) is abundant in precancerous esophageal lesions and is closely related to the malignant progression of esophageal squamous cell carcinoma (ESCC). The invasion of exogenous microorganisms can reshape the immune microenvironment, make the immune system incapacitated, and assist tumor cells in immune escape. A variety of pathogenic microorganisms induce the recruitment of regulatory T cell (Tregs) to allow tumor cells to escape immune surveillance and provide favorable conditions for their own long-term colonization. Tregs are one of the major obstacles to tumor immunotherapy and have a significant positive correlation with the occurrence and development of many kinds of tumors. Because F. nucleatum can instantly enter cells and colonize for a long time, we speculated that F. nucleatum infection could facilitate the immune escape of tumor cells through enrichment of Tregs and promote the malignant progression of ESCC. In this study, we found a significant concordance between F. nucleatum infection and Tregs infiltration. Therefore, we propose the view that chronic infection of F. nucleatum may provide favorable conditions for long-term colonization of itself by recruiting Tregs and suppressing the immune response. At the same time, the massive enrichment of Treg may also weaken the immune response and assist in the long-term colonization of F. nucleatum. We analyzed the correlation between F. nucleatum infection with the clinicopathological characteristics and survival prognosis of the patients. F. nucleatum infection was found to be closely related to sex, smoking, drinking, degree of differentiation, depth of invasion, lymph node metastasis, and clinical stage. The degree of differentiation, depth of infiltration, lymph node metastasis, clinical stage, and F. nucleatum infection are independent risk factors affecting ESCC prognosis. Additionally, the survival rate and median survival time were significantly shortened in the F. nucleatum infection positive group. Therefore, we propose that long-term smoking and alcohol consumption cause poor oral and esophageal environments, thereby significantly increasing the risk of F. nucleatum infection. In turn, F. nucleatum infection and colonization may weaken the antitumor immune response through Treg enrichment and further assist in self-colonization, promoting the malignant progression of ESCC.

Emerging data on nivolumab for esophageal squamous cell carcinoma.

INTRODUCTION: Esophageal cancer (EC) is the seventh most common malignancy in the world. The standard treatment for advanced EC patients is systemic chemotherapy, but few effective cytotoxic agents are available. Recently, nivolumab, a human monoclonal immunoglobulin G4 antibody that inhibits programmed cell death protein 1, has been tested for the treatment of advanced squamous cell carcinoma (ESCC) patients. The ATTRACTION-1 trial showed a promising efficacy of nivolumab monotherapy for advanced ESCC patients after prior chemotherapy. The ATTRACTION-3 phase III trial showed the superiority of nivolumab monotherapy over taxane monotherapy for advanced ESCC patients as a second-line treatment. The CheckMate-577 trial also showed survival benefits of postoperative nivolumab monotherapy in patients with resectable EC. AREAS COVERED: This review mainly outlines emerging data on nivolumab for patients with advanced ESCC after prior chemotherapy. Additionally, this review includes data from the CheckMate-577 trial for patients with resectable EC. EXPERT OPINION: Nivolumab has been approved by the US Food and Drug Administration for treatment after prior chemotherapy in patients with advanced ESCC. Several trials evaluating nivolumab-containing treatments are ongoing in patients with not only advanced EC, but also locally advanced EC, and these investigational treatments might improve the clinical outcomes of EC patients.

A glypican-1-targeted antibody-drug conjugate exhibits potent tumor growth inhibition in glypican-1-positive pancreatic cancer and esophageal squamous cell carcinoma.

An antibody-drug conjugate (ADC) is a promising therapeutic modality because selective and effective delivery of an anti-cancer drug is achieved by drug-conjugated antibody-targeting cancer antigen. Glypican 1 (GPC1) is highly expressed in malignant tumors, including pancreatic ductal adenocarcinoma (PDAC) and esophageal squamous cell carcinoma (ESCC). Herein, we describe the usefulness of GPC1-targeting ADC. Humanized anti-GPC1 antibody (clone T2) was developed and conjugated with monomethyl auristatin E (MMAE) via maleimidocaproyl-valine-citrulline-p-aminobenzyloxycarbonyl (mc-vc-PABC) linkers (humanized GPC1-ADC[MMAE]). Humanized GPC1-ADC(MMAE) inhibited the growth of GPC1-positive PDAC and ESCC cell lines via inducing cycle arrest in the G2/M phase and apoptosis in vitro. The binding activity of humanized GPC1-ADC(MMAE) with GPC1 was comparable with that of the unconjugated anti-GPC1 antibody. The humanized GPC1-ADC(MMAE) was effective in GPC1-positive BxPC-3 subcutaneously xenografted mice but not in GPC1-negative BxPC-3-GPC1-KO xenografted mice. To assess the bystander killing activity of the humanized GPC1-ADC(MMAE), a mixture of GPC1-positive BxPC-3 and GPC1-negative BxPC-3-GPC1-KO-Luc cells were subcutaneously inoculated, and a heterogenous GPC1-expressing tumor model was developed. The humanized GPC1-ADC(MMAE) inhibited the tumor growth and decreased the luciferase signal, measured with an in vivo imaging system (IVIS), which suggests that the suppression of the BxPC-3-GPC1-KO-Luc population. The humanized GPC1-ADC(MMAE) also inhibited the established liver metastases of BxPC-3 cells and significantly improved the overall survival of the mice. It exhibited a potent antitumor effect on the GPC1-positive PDAC and ESCC patient-derived xenograft (PDX) models. Our preclinical data demonstrate that GPC1 is a promising therapeutic target for ADC.

Identification and characterization of prognosis-related genes in the tumor microenvironment of esophageal squamous cell carcinoma.

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is the main pathological subtype of esophageal cancer with high incidence and mortality. Immune and stromal cells in the tumor microenvironment (TME) profoundly affect the development of ESCC. METHODS: In this study, we used the ESTIMATE algorithm to calculate the immune and stromal scores of ESCC samples in The Cancer Genome Atlas (TCGA) database. Next, we used the R package limma to identify differentially expressed genes (DEGs) from high- versus low-immune/stromal score groups and these DEGs were further utilized to analyze the functional annotations, protein-protein interaction (PPI) networks and overall survival of patients with ESCC. Finally, we identified the biological roles of core gene C3AR1 in the TME of ESCC using the TCGA database and in vitro experiments. RESULTS: We obtained the immune and stromal scores of ESCC samples and further evaluated the impact of these scores on the prognosis and clinical parameters of patients with ESCC. Next, we identified 410 DEGs from high- versus low-immune/stromal score groups and to gain better understanding of the biological functions and characteristics of DEGs. Among these DEGs, 69 were correlated with the overall survival of patients with ESCC and C3AR1 was identified as a core gene for the regulation of most genes in the network. We found that C3AR1 was positively correlated with M2 macrophages and immune inhibitory molecules (T-cell immunoglobulin and mucin domain 3 (TIM-3), programmed cell death-1 (PD-1)), but not with M1 macrophages. We also observed a higher expression of CD163 and CD206, which were the markers for M2 macrophages in the TLQP-21 TFA (the agonist of C3AR1)groups than in the control groups. CONCLUSION: Based on the ESTIMATE algorithm, we obtained and characterized prognosis-related genes in the TME of ESCC samples from the TCGA database. We have further revealed that C3AR1 may cause an immunosuppressive microenvironment by affecting the polarization of macrophages to M2 phenotype and lead to the progression of ESCC, which indicates that C3AR1 may be a potential target for immunotherapy.

Clinical utility of the systemic immune-inflammation index for predicting survival in esophageal squamous cell carcinoma after radical radiotherapy.

Aim: To explore the clinical utility of the systemic immune-inflammation index (SII) for predicting the prognosis of esophageal squamous cell carcinoma (ESCC). Patients & methods: After calculating the SII in 180 patients with ESCC, the relationship between SII values and the pre-/post-radiotherapy SII ratio and overall survival was determined. Results: The median overall survival was 649 days for the entire group and 909 and 466 days for the high and low pre-/post-radiotherapy SII ratio groups, respectively. Multivariate analysis identified Karnofsky performance status (p = 0.045), lymphatic metastasis (p = 0.032), mid-radiotherapy SII (p < 0.001) and pre-/post-radiotherapy SII ratio (p = 0.003) as independent prognostic factors. Conclusion: The pre-/post-radiotherapy SII ratio and mid-radiotherapy SII are potentially effective markers for predicting ESCC prognosis.

Lay abstract The systemic immune-inflammation index (SII) is calculated from the counts of peripheral blood platelets (P), neutrophils (N) and lymphocytes (L) per liter according to the formula SII = P × N/L. The SII is associated with poor survival in certain cancer types. However, some reports have examined the prognostic value of the SII in patients with esophageal squamous cell carcinoma (ESCC) who were undergoing radiotherapy or radical chemoradiotherapy. As such, the current study sought to investigate the clinical prognostic value of the SII during radiotherapy and the ratio of the SII before and after radiotherapy in patients with ESCC who were undergoing chemoradiotherapy or radiotherapy. The study found that the pre-/post-radiotherapy SII ratio and mid-radiotherapy SII are potentially effective markers for predicting ESCC prognosis.

Comprehensive Analysis of PD-L1 Expression, Immune Infiltrates, and m6A RNA Methylation Regulators in Esophageal Squamous Cell Carcinoma.

Background: Esophageal squamous cell carcinoma (ESCC) is one of the most common cancer types and represents a threat to global public health. N6-Methyladenosine (m6A) methylation plays a key role in the occurrence and development of many tumors, but there are still few studies investigating ESCC. This study attempts to construct a prognostic signature of ESCC based on m6A RNA methylation regulators and to explore the potential association of these regulators with the tumor immune microenvironment (TIME). Methods: The transcriptome sequencing data and clinical information of 20 m6A RNA methylation regulators in 453 patients with ESCC (The Cancer Genome Atlas [TCGA] cohort, n = 95; Gene Expression Omnibus [GEO] cohort, n = 358) were obtained. The differing expression levels of m6A regulators between ESCC and normal tissue were evaluated. Based on the expression of these regulators, consensus clustering was performed to investigate different ESCC clusters. PD-L1 expression, immune score, immune cell infiltration and potential mechanisms among different clusters were examined. LASSO Cox regression analysis was utilized to obtain a prognostic signature based on m6A RNA methylation modulators. The relationship between the risk score based on the prognostic signature and the TIME of ESCC patients was studied in detail. Results: Six m6A regulators (METTL3, WTAP, IGF2BP3, YTHDF1, HNRNPA2B1 and HNRNPC) were observed to be significantly highly expressed in ESCC tissues. Two molecular subtypes (clusters 1/2) were determined by consensus clustering of 20 m6A modulators. The expression level of PD-L1 in ESCC tissues increased significantly and was significantly negatively correlated with the expression levels of YTHDF2, METL14 and KIAA1429. The immune score, CD8 T cells, resting mast cells, and regulatory T cells (Tregs) in cluster 2 were significantly increased. Gene set enrichment analysis (GSEA) shows that this cluster involves multiple hallmark pathways. We constructed a five-gene prognostic signature based on m6A RNA methylation, and the risk score based on the prognostic signature was determined to be an independent prognostic indicator of ESCC. More importantly, the prognostic value of the prognostic signature was verified using another independent cohort. m6A regulators are related to TIME, and their copy-number alterations will dynamically affect the number of tumor-infiltrating immune cells. Conclusion: Our study established a strong prognostic signature based on m6A RNA methylation regulators; this signature was able to accurately predict the prognosis of ESCC patients. The m6A methylation regulator may be a key mediator of PD-L1 expression and immune cell infiltration and may strongly affect the TIME of ESCC.

Tumor infiltrating lymphocyte signature is associated with single nucleotide polymorphisms and predicts survival in esophageal squamous cell carcinoma patients.

PURPOSE: Esophageal cancer is the sixth leading cause of cancer-related death worldwide, and is associated with a poor prognosis. Stromal tumor infiltrating lymphocytes (sTIL) and certain single nucleotide polymorphisms (SNPs) have been found to be predictive of patient survival. In this study, we explored the association between SNPs and sTIL regarding the predictability of disease-free survival in patients with esophageal squamous cell carcinoma (ESCC). MATERIALS AND METHODS: We collected 969 pathologically confirmed ESCC patients from 2010 to 2013 and genotyped 101 SNPs from 59 genes. The number of sTIL for each patient was determined using an automatic algorithm. A Kruskal-Wallis test was used to determine the association between genotype and sTIL. The genotypes and clinical factors related to survival were analyzed using a Kaplan-Meier curve, Cox proportional hazards model, and log-rank test. RESULTS: The median age of the patients was 67 (42-85 years), there was a median follow-up of 851.5 days and 586 patients died. The univariable analysis showed that 10 of the 101 SNPs were associated with sTIL. Six SNPs were also associated with disease-free survival. A multivariable analysis revealed that sTIL, rs1801131, rs25487, and rs8030672 were independent prognostic markers for ESCC patients. The model combining SNPs, clinical characteristics and sTIL outperformed the model with clinical characteristics alone for predicting outcomes in ESCC patients. CONCLUSION: We discovered 10 SNPs associated with sTIL in ESCC and we built a model of sTIL, SNPs and clinical characteristics with improved prediction of survival in ESCC patients.