A novel amino acid metabolism-related gene signature to predict the overall survival of esophageal squamous cell carcinoma patients.

Background: Esophageal squamous cell carcinoma (ESCC) has a poor early detection rate, prognosis, and survival rate. Effective prognostic markers are urgently needed to assist in the prediction of ESCC treatment outcomes. There is accumulating evidence of a strong relationship between cancer cell growth and amino acid metabolism. This study aims to determine the relationship between amino acid metabolism and ESCC prognosis. Methods: This study comprehensively evaluates the association between amino acid metabolism-related gene (AAMRG) expression profiles and the prognosis of ESCC patients based on data from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) databases. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to verify the expression of prognosis-related genes. Results: A univariate Cox regression analysis of TCGA data identified 18 prognosis-related AAMRGs. The gene expression profiles of 90 ESCC tumor and normal tissues were obtained from the GSE20347 and GSE67269 datasets. Two differently expressed genes (DEGs) were considered as ESCC prognosis-related genes; and they were branched-chain amino acid transaminase 1 (BCAT1) and methylmalonic aciduria and homocystinuria type C protein (MMACHC). These two AAMRGs were used to develop a novel AAMRG-related gene signature to predict 1- and 2-year prognostic risk in ESCC patients. Both BCAT1 and MMACHC expression were verified by RT-qPCR. A prognostic nomogram that incorporated clinical factors and BCAT1 and MMACHC gene expression was constructed, and the calibration plots showed that it had good prognostic performance. Conclusions: The AAMRG signature established in our study is efficient and could be used in clinical settings to predict the early prognosis of ESCC patients.

Tumor immune microenvironment remodeling and prognosis of patients with esophageal squamous cell carcinoma after neoadjuvant chemotherapy with and without immunotherapy: a retrospective cohort study.

Background: Immunochemotherapy was an emerging neoadjuvant treatment mode that can potentially benefit patients with esophageal carcinoma, but its synergistic mechanism and impact on the tumor immune microenvironment were still unclear. The purpose of this study was to investigate the outcomes of neoadjuvant chemotherapy (nCT) and neoadjuvant immunochemotherapy (nICT) in tumor microenvironment (TME) remodeling among patients with esophageal squamous cell carcinoma (ESCC) and to evaluate the prognostic value of immune-related biomarkers and clinicopathological characteristics. Methods: Patients with locally advanced ESCC who underwent neoadjuvant therapy followed by esophagectomy at the Fourth Hospital of Hebei Medical University between December 2019 and March 2022 were enrolled in this retrospective study. We examined TME features and immune antigen-related biomarkers before and after neoadjuvant therapy. Logistic and Cox regression model were used to evaluate the correlation between these factors and other clinical features and outcomes. Results: A total of 50 eligible participants were analyzed, including 31 males (62%), 25 patients of ≥65 years old, 4/28/18 of upper/middle/lower thoracic cancer, 25/17/8 of poor/moderate/high tumor differentiation, 8/42 of cT1+2/T3+4 stages and 30/20 of cN0/N+ stages. In the entire cohort, the rates of pathological complete response (pCR) and major pathological response (MPR) were 18% and 30%, respectively. pCR rates were 7.1% and 22.2% (χ2=0.699; P=0.40) MPR rates were 7.1% and 38.9% (χ2=4.837; P=0.03) in the nCT and nICT groups, respectively. Compared with the non-pCR patients, the pCR patients had a higher baseline programmed cell death ligand-1 (PD-L1) tumor proportion score (TPS) positive expression rate (16.7% vs. 77.8%, χ2=13.089; P<0.001). Following neoadjuvant therapy, the expression rates of PD-L1, CD3+ T cells, and CD8+ T cells in the tumor tissue was higher in the nICT group compared to the nCT group (P<0.05). Deficient expression of mismatch repair (MMR) genes was only observed in one patient (2%). Among patient-related biomarkers, lymphocyte and neutrophil counts decreased after treatment, with no significant changes in the neutrophil-to-lymphocyte ratio or platelet-to-lymphocyte ratio (PLR). Cox regression analysis showed that pretreatment, well-differentiated tumors and positive PD-L1 status were positive predictors of MPR (P<0.05). MPR was an independent predictor of disease-free survival (DFS) (P=0.03). Conclusions: Compared to nCT, nICT could more significantly upregulates PD-L1 TPS, PD-L1 combined positive score (CPS), CD3+ T cells, and CD8+ T cells. Pretreatment tumor differentiation and PD-L1 TPS level could be predictive of MPR. Our findings suggested that the combination of chemotherapy and immunotherapy may be more beneficial for activating anti-tumor immunity in the TME.

Clinicopathological significance of cancer stem cell marker CD44/SOX2 in esophageal squamous cell carcinoma (ESCC) patients and construction of a nomogram to predict overall survival.

Background: Esophageal squamous cell carcinoma (ESCC), a prevalent malignancy within the upper gastrointestinal system, is characterized by its unfavorable prognosis and the absence of specific indicators for outcome prediction and high-risk case identification. In our research, we examined the expression levels of cancer stem cells (CSCs), markers CD44/SOX2 in ESCC, scrutinized their association with clinicopathological parameters, and developed a predictive nomogram model. This model, which incorporates CD44/SOX2, aims to forecast the overall survival (OS) of patients afflicted with ESCC. Methods: Immunohistochemistry was utilized to detect the expression levels of CD44 and SOX2 in both cancerous and paracancerous tissues of 68 patients with ESCC. The correlation between CD44/SOX2 expression and clinicopathological parameters was subsequently analyzed. Factors impacting the prognosis of ESCC patients were assessed through univariate and multivariate Cox regression analyses. Leveraging the results of these multivariate regression analyses, a nomogram prognostic model was established to provide individualized predictions of ESCC patient survival outcomes. The predictive accuracy of the nomogram prognostic model was evaluated using the consistency index (C-index) and calibration curves. Results: The expression levels of CD44 were markedly elevated in the tumor tissues of ESCC patients. Similarly, SOX2 was significantly overexpressed in the tumor tissues of ESCC patients. The positive expression of SOX2 in ESCC demonstrated a strong correlation with both the pathological T-stage and the presence of carcinoembryonic antigen. CD44 and SOX2 co-positive expression was significantly associated with the pathological T-stage and tumor node metastasis (TNM) stage. Furthermore, ESCC patients exhibiting CD44-positive expression in their tumor tissue generally had a more adverse prognosis. The co-expression of CD44 and SOX2 resulted in a grimmer prognosis compared to patients with other combinations. Multivariate Cox regression analysis identified the co-expression of CD44 and SOX2, the pathological T-stage, and lymph node metastasis as independent prognostic indicators for ESCC patients. The three identified variables were subsequently incorporated into a nomogram for predicting OS. The C-index of the measurement model and the area under the curve of the subjects' work characteristics showed good individual prediction. This prognostic model stratified patients into low- and high-risk categories. Analysis revealed that the 5-year OS rate was significantly higher in the low-risk group compared to the high-risk group. Conclusions: Elevated CD44 levels, indicative of CSC presence, are intimately linked with the oncogenesis of ESCC and are strongly predictive of unfavorable patient outcomes. Concurrently, the SOX2 gene exhibits a heightened expression in ESCC, markedly accelerating tumor progression and fostering more extensive disease infiltration. The co-expression of CD44 and SOX2 correlates significantly with ESCC patient prognosis, serving as a reliable, independent prognostic marker. Our constructed nomogram, incorporating CD44/SOX2 expression, enhances the prediction of OS and facilitates risk stratification in ESCC patients.

Identification of tumor antigens for mRNA vaccines and ferroptosis-related landscape in esophageal squamous cell carcinoma.

Background: Ferroptosis, an iron-dependent form of cell death that is characterized by lipid peroxidation, has been implicated in conferring resistance to cancer therapies and may contribute to the pathogenesis of esophageal squamous cell carcinoma (ESCC). Furthermore, messenger RNA (mRNA) vaccines have emerged as a promising modality in the treatment arsenal against diverse malignancies. The aim of the study was to investigate the role of ferroptosis subtypes in ESCC and the immune microenvironment, as well as to identify key genes that could serve as targets for mRNA vaccine development. Methods: Gene expression profiles and clinical data from 79 and 358 ESCC patients were collected from The Cancer Genome Atlas and Gene Expression Omnibus databases. Subsequently, we identified tumor mutational burden (TMB), immune microenvironment scores, and immune checkpoint and immune cell dysfunction genes for each ferroptosis subtype. Furthermore, we utilized weighted gene co-expression network analysis (WGCNA) to describe the immune landscape of ESCC and identify key genes for mRNA vaccine development. Results: Our analysis revealed that MMD, MTDH, and TRFC were overexpressed ferroptosis genes in ESCC. In addition, ESCC was categorized into two ferroptosis subtypes, namely FS1 and FS2. Notably, FS2 exhibited a poorer prognosis, higher TMB, and increased immune cell infiltration when compared to FS1. The ferroptosis landscape analysis further revealed the presence of three distinct states. WGCNA analysis identified different modules of interest emerging as an independent prognostic factor and enriched with hub genes that could serve as targets for mRNA vaccine development. Conclusions: The ferroptosis subtypes demonstrated significant associations with both prognosis and the immune microenvironment in ESCC. Additionally, the module of interest identified through immune landscape analysis represented an independent prognostic factor, with its contained genome offering promising targets for mRNA vaccine development.

Prognosis for local radical treatment in patients with esophageal squamous cell carcinoma with low-risk oligometastatic recurrence after curative resection: a retrospective cohort study.

Background: Patients with esophageal carcinoma (EC) with recurrent disease have a poor prognosis. A limited numbers of metastases, safely treatable with curative intent, diagnosed after curative esophagectomy may be defined as oligometastatic recurrence (OLR). However, the appropriate number of metastases and metastatic organs involved remains incompletely characterized. And the role of local therapy in OLR after radical esophagectomy remains unknown. Therefore, this study aimed to more accurately define low-risk OLR in patients with esophageal squamous cell carcinoma (ESCC) treated with radical resection and investigate the role of chemotherapy combined with local treatment (CCLT) in these patients. Methods: A total of 83 sequential patients with ESCC who underwent radical esophagectomy, with an Eastern Cooperative Oncology Group (ECOG) performance status ≤2, with ability to tolerate chemotherapy (CT) and local treatment, and with newly diagnosed recurrence between January 2010 and May 2019 in our hospital were recruited. Overall survival (OS) curves after recurrence were analyzed using the Kaplan-Meier method, and a log-rank test was used to assess the OS differences. Cox proportional hazards regression analysis was performed to identify independent factors associated with 2-year OS. Regular follow-up examinations were assessed by thoracic and upper abdominal computed tomography (CT) scanning every 3 months in the first year, every 6 months over the next 2 years, and yearly thereafter. Results: Of the 83 patients with ESCC (71 males and 12 females), the median age was 56 years (range, 37-79 years). Thirty-five patients with ESCC with ≤5 metastases safely treatable with curative intent located in a single organ had a favorable OS compared to 48 patients with metastases located in 2-3 organs with or without regional recurrence and/or regional lymph node (LN) metastases. In our study, low-risk OLR was defined as the presence of ≤5 metastases safely treatable with curative intent in a single organ and was compared to patients with 2-3 organs involved. The 2-year OS of patients with low-risk OLR with liver oligometastases was significantly worse than survival in patients with lung oligometastases (0% vs. 61.1%, P=0.009). Patients with ESCC in the low-risk OLR group treated with CCLT had a better 2-year OS after recurrence than those who received CT alone (66.7% vs. 30.4%, P=0.003). The multivariable Cox regression model identified treatment method [hazard ratio (HR) 3.920, P=0.02] as an independent factor affecting OS after recurrence for low-risk OLR. Conclusions: Low-risk OLR was defined as ≤5 metastases safely treatable with curative intent in a single organ. Patients with ESCC with low-risk OLR after curative resection treated with CCLT have a favorable OS compared to those treated with CT alone. CCLT is a promising treatment option for patients with ESCC and low-risk OLR.

Safety and short-term outcomes of esophagectomy after neoadjuvant immunotherapy combined with chemotherapy or chemoradiotherapy for locally advanced esophageal squamous cell cancer: analysis of two phase-II clinical trials.

Background: Preoperative chemotherapy (CT) or chemoradiotherapy (CRT) show survival benefits in patients with locally advanced esophageal squamous cell carcinoma (ESCC); however, ESCC patients still have a dismal prognosis. We conducted two phase-II, single-armed clinical trials to assess the potential benefits, efficacy, feasibility, and safety of esophagectomy after combining preoperative CT or CRT and neoadjuvant programmed cell death protein 1 (PD-1) inhibitors in the treatment of ESCC. Methods: Patients were included with histologically confirmed ESCC (clinical stage II-IVA according to the American Joint Committee on Cancer 8th staging system) from two phase-II, single-arm trials (NCT04506138 and NCT03940001). Patients underwent two doses of intravenous PD-1 inhibitor (either camrelizumab or sintilimab) every 3 weeks, combined with two cycles of either CT or CRT. The primary endpoint of the study was the safety and short-term outcomes of esophagectomy as measured by the risk of developing complications within 30 days, after the combination of preoperative PD-1 inhibitor and CT or CRT Secondary endpoint was to evaluate the pCR rates (pT0N0), primary tumor pCR rates (pT0), operation time, postoperative stay, and 30-day mortality rate between both groups. Results between both groups were compared using a multivariable log-binomial regression model to obtain the adjusted relative risk ratios (RRs). Results: Between May 2019 and June 2022, 55 patients were included. All patients completed neoadjuvant therapy. Age, sex, performance status, clinical stage, histologic subtype, procedure type, operative time, and blood loss volume were similar between the two groups. The primary tumor pCR rates were 52.9% in the nICRT group and 21.6% in the nICT group (P=0.03), while the postoperative pCR rates were 41.2% in the nICRT group and 21.6% in the nICT group (P=0.19). The minimally invasive surgery rates were 89.2% (33/37) in the nICT group and 94.1% (16/17) in the nICRT group. The risk of developing pulmonary, anastomotic, or other complications were similar between the two groups. Conclusions: Esophagectomy was safe after the addition of the PD-1 inhibitor to preoperative CT or CRT in ESCC neoadjuvant therapies. Follow-up and the exploratory endpoints, including biomarkers analyses, are ongoing.

Application of predictive model based on CT radiomics and machine learning in diagnosis for occult locally advanced esophageal squamous cell carcinoma before treatment: A two-center study.

PURPOSE: Development and validation of a radiomics model for predicting occult locally advanced esophageal squamous cell carcinoma (LA-ESCC) on computed tomography (CT) radiomic features before implementation of treatment. METHODS: The study retrospectively collected 574 patients with esophageal squamous cell carcinoma (ESCC) from two medical centers, which were divided into three cohorts for training, internal and external validation. After delineating volume of interest (VOI), radiomics features were extracted and subjected to feature selection using three robust methods. Subsequently, 10 machine learning models were constructed, among which the optimal model was utilized to establish a radiomics signature. Furthermore, a predictive nomogram incorporating both clinical and radiomics signatures was developed. The performance of these models was evaluated through receiver operating characteristic curves, calibration curves, decision curve analysis as well as measures including accuracy, sensitivity, and specificity. RESULTS: A total of 19 radiomics features were selected. The multilayer perceptron (MLP), which was found to be optimal, achieved an AUC of 0.919, 0.864 and 0.882 in the training, internal and external validation cohorts, respectively. Similarly, MLP showed good accuracy in distinguish occult LA-ESCC in subgroup of cT1-2N0M0 diagnosed by clinicians with 0.803 and 0.789 in two validation cohorts respectively. By incorporating the radiomics signature with clinical signature, a predictive nomogram demonstrated superior prediction performance with an AUC of 0.877 and accuracy of 0.85 in external validation cohort. CONCLUSION: The radiomics and machine learning model can offers improved accuracy in prediction of occult LA-ESCC, providing valuable assistance to clinicians when choosing treatment plans.

Molecular Mechanism of WWOX Inhibiting the Development of Esophageal Cancer by Inhibiting Hippo Signaling Pathway.

With the emergence of combined surgical treatments, complemented by radiotherapy and chemotherapy, survival rates for esophageal cancer patients have improved, but the overall 5-year survival rate remains low. Therefore, there is an urgent need for further research into the pathogenesis of esophageal cancer and the development of effective prevention, diagnosis, and treatment methods. We initially utilized the GeneCards and DisGeNET databases to identify the esophageal cancer-associated gene WWOX (WW domain containing oxidoreductase). Subsequently, we employed RT-qPCR (Reverse transcription-quantitative PCR) and WB (western blot) to investigate the differential expression of WWOX in HEEC (human esophageal endotheliocytes) and various ESCC (esophageal squamous cell carcinoma) cell lines. We further evaluated alterations in cell proliferation, migration and apoptosis via CCK8 (cell counting kit-8) and clonal formation, Transwell assays and flow cytometry. Additionally, we investigated changes in protein expressions related to the Hippo signaling pathway (YAP/TEAD) through RT-qPCR and WB. Lastly, to further elucidate the regulatory mechanism of WWOX in ESCC, we performed exogenous YAP rescue experiments in ESCC cells with WWOX overexpression to investigate the alterations in apoptosis and proliferation. Results indicated that the expression of WWOX in ESCC was significantly downregulated. Subsequently, upon overexpression of WWOX, ESCC cell proliferation and migration decreased, while apoptosis increased. Additionally, the expression of YAP and TEAD were reduced. However, the sustained overexpression of YAP attenuated the inhibitory effects of WWOX on ESCC cell malignancy. In conclusion, WWOX exerts inhibitory effects on the proliferation and migration of ESCC and promotes apoptosis by suppressing the Hippo signaling pathway. These findings highlight the potential of WWOX as a novel target for the diagnosis and treatment of esophageal cancer.

Neoadjuvant Chemoradiotherapy Upregulates the Immunogenicity of Cold to Hot Tumors in Esophageal Cancer Patients.

Objective: To test the hypothesis that neoadjuvant chemoradiotherapy (NACRT) is more effective against hot esophageal squamous cell carcinoma (ESCC) and that it may upregulate tumor immunogenicity. Background: There have been several recent reports showing the efficacy of immune check-point inhibitors (ICIs) against esophageal cancer, especially immunologically hot tumors. In addition, several studies have suggested that chemotherapy and radiotherapy may convert cold tumors to hot tumors. Methods: Of 105 ESCC patients who underwent surgery after NACRT between 2010 and 2018 at our hospital, 99 whose biopsy tissue samples were obtained were enrolled. Based on immunohistochemical analysis, tumors that were FOXA1 (+) and/or EYA2 (+) were defined as hot tumors, others were cold tumors. We then investigated the association between tumor immunogenicity and clinicopathological features. Results: The 29 patients with hot tumors before NACRT had a significantly better 5-year disease-specific survival (DSS) rate than the remaining 70 patients with cold tumors (85% vs 64%; P = 0.036). In a multivariate analysis, tumor immunogenicity was a significant independent predictor of DSS. Of 68 patients without a pathological complete response (non-pCR) in their primary tumor, 51 (75%) had hot tumors after NACRT. Moreover, 75% (36/48) of tumors that were cold before NACRT were converted to hot tumors after NACRT. Conclusions: Patients with hot ESCC tumors treated with NACRT plus esophagectomy had a better prognosis than those with cold tumors. NACRT upregulated cold tumor immunogenicity to hot tumors, suggesting NACRT may increase the sensitivity of ESCC to adjuvant ICIs.

CircRNA_101491 regulated the radiation sensitivity of esophageal squamous cell carcinomas via sponging miR-125a-5p.

BACKGROUND: At present, it has been found that many patients have acquired resistance to radiotherapy, which greatly reduces the effect of radiotherapy and further affects the prognosis. CircRNAs is involved in the regulation of radiosensitivity of many kinds of tumor cells. Therefore, the main purpose of this study is to explore the regulatory effect of CircRNA_101491 on radiosensitivity of ESCC and its related mechanism. METHODS: We established ESCC radiation-resistant cell line (KYSE150R cell) by gradient dose method, and tested the difference of KYSE150 between KYSE150R cell and parent cell in vitro. Then, after knocking down the expression of CircRNA_101491, a series of in vitro experiments were conducted to verify the effects of CircRNA_101491 on the phenotype and radiosensitivity of KYSE150R cells, and further analyzed the related regulatory mechanism. In addition, we also used the model of transplanted tumor in nude mice to investigate the effect of CircRNA_101491 on the radiosensitivity of ESCC in vivo. RESULTS: According to a series of in vitro experiments, we confirmed that KYSE150R cells lost the epithelial phenotype and obtained interstitial cell-like phenotype, and found that CircRNA_101491 was highly expressed in KYSE150R cells. In addition, we found that knocking down the expression of CircRNA_101491 will lift the inhibition of miR-125a-5p, and then reverse the process of EMT, accelerate the process of apoptosis, thus play a role in radiosensitization. The in vivo experiment of transplanted tumor in nude mice also showed that knocking down the expression of CircRNA_101491 could enhance the radiosensitivity of ESCC. CONCLUSION: In conclusion, we confirmed that interfering with the expression of CircRNA_101491 can relieve the inhibition of miR-125a-5p, thus reverse the process of interstitial phenotype, accelerate the process of apoptosis, and enhance the radiosensitivity of ESCC.

Advancements in immunotherapy for advanced esophageal squamous cell carcinoma: a comprehensive review of current strategies and future directions.

INTRODUCTION: Esophageal cancer (EC), particularly esophageal squamous cell carcinoma (ESCC), is characterized by high incidence and poor prognosis worldwide, necessitating novel therapeutic approaches like immunotherapy. This review explores the impact of immune checkpoint inhibitors (ICIs) on ESCC, especially focusing on PD-1/PD-L1 and CTLA-4 inhibitors. Our literature search, conducted across databases including PubMed, Web of Science, and EMBASE, from January 2010 to December 2023, aimed at identifying advancements, challenges, and future directions in the use of immunotherapy for ESCC. AREAS COVERED: We provide a detailed analysis of clinical trials evaluating the efficacy of ICIs as monotherapy and in combination with chemotherapy, radiotherapy, and targeted therapy for locally advanced ESCC. Our findings highlight the significant survival benefits offered by ICIs, albeit with varying efficacy across patient populations, emphasizing the need for precise biomarkers to tailor treatment strategies. EXPERT OPINION: The integration of immunotherapy into the ESCC treatment paradigm represents a significant shift, improving survival outcomes. Future research should focus on optimizing combination therapies and novel immunotherapeutic agents, incorporating genetic and tumor microenvironment analyses to enhance patient selection and treatment efficacy.

Vimentin, inversely correlating with infiltration of CD8 + T lymphocytes, promotes nuclear translocation of PD-L1 in esophageal squamous cell carcinoma.

Vimentin has been considered a canonical marker of epithelial-mesenchymal transition (EMT) and is associated with tumor escape characterized by aberrant PD-L1 expression. However, whether there is a relationship between vimentin and PD-L1 in esophageal squamous cell carcinoma (ESCC) remains poorly understood. The immunological involvement of vimentin in ESCC was first analyzed by multiplex immunofluorescence staining in ESCC tissue microarray followed by a xenografted mouse model. In vivo, C57BL/6 mice were subcutaneously transplanted with AKR cells after stable silencing of vimentin. In vivo results showed that in addition to PD-L1 and PD-L2 expression, vimentin expression was inversely correlated with CD8+ T-cell infiltration. Mechanistically, vimentin can directly interact with PD-L1 and promote nuclear translocation of PD-L1 in AKR cells. In addition, SEMA6C, STC-2 and TRAILR2 were identified as cytokines modulated by vimentin. Blockade of STC-2 and TRAILR2 in co-culture with their own primary antibodies was shown to recruit more CD8+ T cells than controls. Together, these data strongly suggest targeting Vimenin to overcome the immune cycle in ESCC.

IKBIP promotes tumor development via the akt signaling pathway in esophageal squamous cell carcinoma.

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is one of the most common cancers worldwide. Inhibitor of kappa B kinase interacting protein (IKBIP) has been reported to promote glioma progression, but its role in other cancers remains unclear. This study aimed to investigate the role of IKBIP and its underlying molecular mechanisms in ESCC. METHODS: The mRNA expression of IKBIP was analyzed using multiple cancer databases. Immunohistochemistry was performed to detect IKBIP protein expression in ESCC tissues and adjacent normal tissues, and Kaplan‒Meier survival and Cox regression analyses were carried out. The effects of IKBIP knockdown (or overexpression) on ESCC cells were detected by cell viability, cell migration, flow cytometry and Western blot assays. LY-294002 was used to validate the activation of the AKT signaling pathway by IKBIP. Finally, the role of IKBIP in ESCC was verified in a xenograft model. RESULTS: Both bioinformatics analysis and immunohistochemistry indicated that IKBIP expression in ESCC tissues was significantly increased and was associated with the prognosis of ESCC patients. In vitro experiments revealed that IKBIP knockdown significantly inhibited the proliferation and migration of ESCC cells, and induced cell apoptosis and G1/S phase arrest. Molecular mechanism results showed that the AKT signaling pathway was further activated after IKBIP overexpression, thereby increasing the proliferation and migration abilities of ESCC cells. In vivo study confirmed that IKBIP promoted the initiation and development of ESCC tumors in mice. CONCLUSIONS: IKBIP plays a tumor-promoting role in ESCC and may serve as a predictive biomarker and a potential therapeutic target for ESCC.

Discovery and validation of combined biomarkers for the diagnosis of esophageal intraepithelial neoplasia and esophageal squamous cell carcinoma.

Early diagnosis and intervention of esophageal squamous cell carcinoma (ESCC) can improve the prognosis. The purpose of this study was to identify biomarkers for ESCC and esophageal precancerous lesions (intraepithelial neoplasia, IEN). Based on the proteomic and genomic data of esophageal tissue including previously reported data, up-regulated proteins with copy number amplification in esophageal cancer were screened as candidate biomarkers. Five proteins, including KDM2A, RAD9A, ECT2, CYHR1 and TONSL, were confirmed by immunohistochemistry on ESCC and normal esophagus (NE). Then, we investigated the expression of 5 proteins in 236 participants (60 NEs, 93 IENs and 83 ESCCs) which were randomly divided into training set and test set. When distinguishing ESCC from NE, the area under curve (AUC) of the multiprotein model was 0.940 in the training set, while the lowest AUC of a protein was 0.735. In the test set, the results were similar. When distinguishing ESCC from IEN or distinguishing IEN from NE, the diagnostic efficiency of the multi-protein models were also improved compared with that of single protein. Our findings suggest that combined detection of KDM2A, RAD9A, ECT2, CYHR1 and TONSL can be used as potential biomarkers for the early diagnosis of ESCC and precancerous lesion development prediction. SIGNIFICANCE: Candidate biomarkers including KDM2A, RAD9A, ECT2, CYHR1 and TONSL screened by integrating genomic and proteomic data from the esophagus can be used as potential biomarkers for the early diagnosis of esophageal squamous cell carcinoma and precancerous lesion development prediction.

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.

Hypoxia­regulated exosomal miR­185 inhibits esophageal squamous cell carcinoma progression and predicts prognosis.

Despite advances in treatment and diagnosis, the prognosis of patients with esophageal squamous cell carcinoma (ESCC) remains poor. MicroRNAs (miRNAs/miRs) are associated with prognosis in esophageal cancer, indicating that they may help guide treatment decisions. The aim of the present study was to explore exosomal miR-185 as a candidate prognostic biomarker and therapeutic target in ESCC, to investigate its biological function and clinical significance, and to ascertain the applicability of circulating exosomal miR-185 for the development of targeted drugs for ESCC treatment. A GeneChip miRNA array was used to compare exosomal miRNA expression in ESCC cell lines under hypoxia with those under normoxia. Exosomal miR-185 expression was then confirmed by reverse transcription-quantitative PCR. Patient background and prognosis were compared between high and low miR-185 expression groups. Functional analyses were performed to evaluate the antitumor effects of miR-185 in ESCC cells. Global Gene Set Enrichment Analysis of The Cancer Genome Atlas data was also performed, and differentially expressed exosomal miRNAs under hypoxia were identified compared to those under normoxia. Hypoxia markedly decreased the expression of exosomal miR-185 in KYSE-960 and T.Tn cell culture media. Overexpression of miR-185 suppressed the migration, invasion and colony-forming abilities of ESCC lines, and also suppressed cell cycle progression and promoted apoptosis after cisplatin treatment. Notably, high miR-185 expression was associated with signaling pathways related to cell death, DNA damage and p53. Furthermore, circulating exosomal miR-185 levels were associated with cN and cStage, and could predict progression-free survival and disease-specific survival of patients with ESCC after initial treatment. In conclusion, miR-185 holds potential as a prognostic biomarker and therapeutic target in ESCC.

Lysophosphatidic acid promotes ESCC progression by increasing the level of CCL2 secreted by esophageal epithelial cells.

BACKGROUND: Lysophosphatidic acid (LPA) is a small bioactive lipid which acts as a potent regulator in various tumor progressions through six G-protein-coupled receptors (LPA1-LPA6). Our previous study demonstrated that the LPA-producing enzyme, autotaxin (ATX), was upregulated in esophageal squamous cell carcinoma (ESCC) and ATX high expression levels indicated a poor prognosis. Esophageal squamous cell carcinoma is a type of malignant tumor which originates from epithelial cells. Its progression can be affected by the interaction between cancer cells and normal cells. However, the impact of LPA on the interaction between esophageal epithelial cells and cancer cells in the development of ESCC remains uncertain. METHODS: MTS and Edu assays were performed to determine ESCC cell proliferation in culture medium (CM) derived from LPA-stimulated esophageal epithelial cells (Het-1a). A wound healing assay, transwell migration and an invasion assay were performed to assess the metastatic ability of ESCC cells. Cytokine array analysis was conducted to detect the differentially secreted cytokines in CM. The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases were utilized to uncover the pathways and cytokines that are influenced by LPA in ESCC. Immunohistochemical staining was employed to measure the expression of ATX and CCL2 in early-stage ESCC. Quantitative real-time PCR, western blot, enzyme-linked immunosorbent assay and an antibody neutralization assay were employed to measure the mechanism of LPA-mediated communication between epithelial cells and cancer cells. RESULTS: Functional experiments showed that exposing ESCC cancer cells to CM from LPA-treated Het-1a results in promoting proliferation, migration, invasion and epithelial-mesenchymal transition processes. Using cytokine array analysis, we discovered that LPA triggers the release of multiple cytokines from epithelial cells. After screening of the TCGA and GEO databases, CCL2 was identified and found to be correlated with ATX expression in ESCC. Furthermore, CCL2 levels in both mRNA expression and secretion were observed to be upregulated in epithelial cells upon stimulation with LPA. Blocking CCL2 effectively reduced the pro-migration influence of CM derived from LPA-treated Het-1a. Mechanism studies have demonstrated that LPA activated the NF-κB signaling pathway through LPA1/3, ultimately causing an increase in CCL2 expression and secretion in Het-1a. CONCLUSIONS: Our findings, taken together, demonstrate that CM from LPA-treated esophageal epithelial cells plays a significant role in promoting the progression of ESCC, with CCL2 acting as the primary regulator.

Overactivation of XBP1 in plasma cells implies worse survival through innate immunity in esophageal squamous cell carcinoma.

To maintain protein homeostasis, X-box binding protein 1 (XBP1) undergoes splicing following the activation of the unfolded protein response (UPR) in response to endoplasmic reticulum (ER) stress. Although targeting ER stress represents a promising therapeutic strategy, a comprehensive understanding of XBP1 at the cellular level and the link between XBP1 and the innate nervous system is lacking. Here, TCGA pancancer datasets from 33 cancer types, scRNA pancancer datasets from 454 patients and bulk RNA-seq datasets from 155 paired esophageal squamous cell carcinoma (ESCC) patients were analyzed. To cope with ER stress, plasma cells tend to activate XBP1 after undergoing bacterial infection and inflammatory signaling from the innate immune system. Patients with high XBP1 expression in their plasma cells have a higher tumor grade and worse survival. However, activation of the innate immune system with increased XBP1 expression in plasma cells correlates with an increased lymphocyte ratio, indicative of a more robust immune response. Moreover, XBP1 activation appears to initiate leukocyte migration at the transcriptional level. Our study revealed that the XBP1-induced UPR could mediate the crosstalk between optimal acquired humoral immune responses and innate immunity in ESCC.

CircMALAT1 promotes cancer stem-like properties and chemoresistance via regulating Musashi-2/c-Myc axis in esophageal squamous cell carcinoma.

The primary challenge in treating esophageal squamous cell carcinoma (ESCC) is resistance to chemotherapy. Cancer stem cell (CSC) is the root cause of tumor drug resistance. Therefore, targeting CSCs has been considered promising therapeutic strategy for tumor treatment. Here, we report that circMALAT1 was significantly upregulated in ESCC CSC-like cells and primary tumors from ESCC patients. Clinically, there was a positive correlation between circMALAT1 expression and ESCC stage and lymph node metastasis, as well as poor prognosis for ESCC patients. In vitro and in vivo functional studies revealed that circMALAT1 promoted CSC-like cells expansion, tumor growth, lung metastasis and drug resistance of ESCC. Mechanistically, circMALAT1 directly interacted with CSC-functional protein Musashi RNA Binding Protein 2 (MSI2). CircMALAT1 inhibited MSI2 ubiquitination by preventing it from interacting with ß-transducin repeat containing protein (BTRC) E3 ubiquitin ligase. Also, circMALAT1 knockdown inhibited the expression of MSI2-regulating CSC-markers c-Myc in ESCC. Collectively, circMALAT1 modulated the ubiquitination and degradation of the MSI2 protein signaling with ESCC CSCs and accelerated malignant progression of ESCC. CircMALAT1 has the potential to serve as a biomarker for drug resistance and as a target for therapy in CSCs within ESCC.

Bacteroidetes promotes esophageal squamous carcinoma invasion and metastasis through LPS-mediated TLR4/Myd88/NF-κB pathway and inflammatory changes.

Gut microbiota plays a crucial role in gastrointestinal tumors. Additionally, gut microbes influence the progression of esophageal cancer. However, the major bacterial genera that affect the invasion and metastasis of esophageal cancer remain unknown, and the underlying mechanisms remain unclear. Here, we investigated the gut flora and metabolites of patients with esophageal squamous cell carcinoma and found abundant Bacteroides and increased secretion and entry of the surface antigen lipopolysaccharide (LPS) into the blood, causing inflammatory changes in the body. We confirmed these results in a mouse model of 4NQO-induced esophageal carcinoma in situ and further identified epithelial-mesenchymal transition (EMT) occurrence and TLR4/Myd88/NF-κB pathway activation in mouse esophageal tumors. Additionally, in vitro experiments revealed that LPS from Bacteroides fragile promoted esophageal cancer cell proliferation, migration, and invasion, and induced EMT by activating the TLR4/Myd88/NF-κB pathway. These results reveal that Bacteroides are closely associated with esophageal cancer progression through a higher inflammatory response level and signaling pathway activation that are both common to inflammation and tumors induced by LPS, providing a new biological target for esophageal cancer prevention or treatment.