Screening for esophageal squamous cell carcinoma: recent advances

The possible molecular mechanism underlying the involvement of the variable shear factor QKI in the epithelial-mesenchymal transformation of oesophageal cancer

OBJECTIVE

Based on the GEO, TCGA and GTEx databases, we reveal the possible molecular mechanism of the variable shear factor QKI in epithelial mesenchymal transformation (EMT) of oesophageal cancer.

METHODS

Based on the TCGA and GTEx databases, the differential expression of the variable shear factor QKI in oesophageal cancer samples was analysed, and functional enrichment analysis of QKI was performed based on the TCGA-ESCA dataset. The percent-spliced in (PSI) data of oesophageal cancer samples were downloaded from the TCGASpliceSeq database, and the genes and variable splicing types that were significantly related to the expression of the variable splicing factor QKI were screened out. We further identified the significantly upregulated circRNAs and their corresponding coding genes in oesophageal cancer, screened the EMT-related genes that were significantly positively correlated with QKI expression, predicted the circRNA-miRNA binding relationship through the circBank database, predicted the miRNA-mRNA binding relationship through the TargetScan database, and finally obtained the circRNA-miRNA-mRNA network through which QKI promoted the EMT process.

RESULTS

Compared with normal control tissue, QKI expression was significantly upregulated in tumour tissue samples of oesophageal cancer patients. High expression of QKI may promote the EMT process in oesophageal cancer. QKI promotes hsa_circ_0006646 and hsa_circ_0061395 generation by regulating the variable shear of BACH1 and PTK2. In oesophageal cancer, QKI may promote the production of the above two circRNAs by regulating variable splicing, and these circRNAs further competitively bind miRNAs to relieve the targeted inhibition of IL-11, MFAP2, MMP10, and MMP1 and finally promote the EMT process.

CONCLUSION

Variable shear factor QKI promotes hsa_circ_0006646 and hsa_circ_0061395 generation, and downstream related miRNAs can relieve the targeted inhibition of EMT-related genes (IL11, MFAP2, MMP10, MMP1) and promote the occurrence and development of oesophageal cancer, providing a new theoretical basis for screening prognostic markers of oesophageal cancer patients.

Endoscopic Resection of Residual or Recurrent Lesions after Circumferential Radiofrequency Ablation for Flat Superficial Esophageal Squamous Cell Neoplasias

The optimal treatment of residual/recurrent superficial esophageal squamous cell neoplasias (SESCNs) after circumferential radiofrequency (RFA) remains unclear. We aimed to report the efficacy and safety of endoscopic resection (ER) of residual/recurrent SESCNs after RFA. Patients who underwent circumferential RFA with residual/recurrent SESCNs and were treated with ER were retrospectively collected. SESCN patients treated with primary endoscopic submucosal dissection (ESD) served as the control group. Eleven patients who underwent RFA had a total of 17 residual (n = 8) or recurrent (n = 9) SESCNs and were treated for ER. EMR failed to remove one residual SESCN. Of the 16 resected specimens, 10 were high-grade intraepithelial neoplasia (HGIN) and six were cancer. Eight cases had neoplasia extending to esophageal ducts/submucosal glands (SMGs). The pathological results may imply three possible routes in which residual/recurrent SESCNs occurred: HGIN without ductal/SMG involvement (37.5%), HGIN with ductal/SMG involvement (25.0%), and SCC with muscularis mucosae or deeper involvement (37.5%). Compared with the control group, the study group had similar procedural speed, en bloc resection rate, R0 resection rate, and complication rate. In conclusion, the safety and efficacy of post-RFA ESD were similar to those of primary ESD. ESD should be the treatment of choice for residual/recurrent SESCNs after initial RFA.

The current state of artificial intelligence in endoscopic diagnosis of early esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is a common malignant tumor of the digestive tract. The most effective method of reducing the disease burden in areas with a high incidence of esophageal cancer is to prevent the disease from developing into invasive cancer through screening. Endoscopic screening is key for the early diagnosis and treatment of ESCC. However, due to the uneven professional level of endoscopists, there are still many missed cases because of failure to recognize lesions. In recent years, along with remarkable progress in medical imaging and video evaluation technology based on deep machine learning, the development of artificial intelligence (AI) is expected to provide new auxiliary methods of endoscopic diagnosis and the treatment of early ESCC. The convolution neural network (CNN) in the deep learning model extracts the key features of the input image data using continuous convolution layers and then classifies images through full-layer connections. The CNN is widely used in medical image classification, and greatly improves the accuracy of endoscopic image classification. This review focuses on the AI-assisted diagnosis of early ESCC and prediction of early ESCC invasion depth under multiple imaging modalities. The excellent image recognition ability of AI is suitable for the detection and diagnosis of ESCC and can reduce missed diagnoses and help endoscopists better complete endoscopic examinations. However, the selective bias used in the training dataset of the AI system affects its general utility.

Comparative analysis of immune checkpoint inhibitors in first-line treatment of esophageal squamous cell carcinoma: a network meta-analysis

Aim: To evaluate the efficacy and safety of first-line immunochemotherapy in the treatment of advanced esophageal squamous cell carcinoma (CRD42021287033). Methods: PubMed, Embase, Cochrane Library and Web of Science were systematically searched to obtain randomized controlled trials, and the outcome indicators of the reports were compared and analyzed. Results: A total of 3163 patients from five reported randomized controlled trials were included in the meta-analysis. The results showed the comprehensive benefits of toripalimab combined with chemotherapy, in terms of overall survival (hazard ratio: 0.59; 95% CI: 0.43-0.81) and progression-free survival (hazard ratio: 0.58; 95% CI: 0.46-0.73). Conclusion: Toripalimab combined with chemotherapy may be a better choice for first-line immunochemotherapy, although this needs to be verified by clinical studies.

Intact regulation of G1/S transition renders esophageal squamous cell carcinoma sensitive to PI3Kα inhibitors

Phosphatidylinositol 3-kinase alpha (PI3Kα) inhibitors are currently evaluated for the therapy of esophageal squamous cell carcinoma (ESCC). It is of great importance to identify potential biomarkers to predict or monitor the efficacy of PI3Kα inhibitors in an aim to improve the clinical responsive rate in ESCC. Here, ESCC PDXs with CCND1 amplification were found to be more sensitive to CYH33, a novel PI3Kα-selective inhibitor currently in clinical trials for the treatment of advanced solid tumors including ESCC. Elevated level of cyclin D1, p21 and Rb was found in CYH33-sensitive ESCC cells compared to those in resistant cells. CYH33 significantly arrested sensitive cells but not resistant cells at G1 phase, which was associated with accumulation of p21 and suppression of Rb phosphorylation by CDK4/6 and CDK2. Hypo-phosphorylation of Rb attenuated the transcriptional activation of SKP2 by E2F1, which in turn hindered SKP2-mediated degradation of p21 and reinforced accumulation of p21. Moreover, CDK4/6 inhibitors sensitized resistant ESCC cells and PDXs to CYH33. These findings provided mechanistic rationale to evaluate PI3Kα inhibitors in ESCC patients harboring amplified CCND1 and the combined regimen with CDK4/6 inhibitors in ESCC with proficient Rb.

Daurisoline suppresses esophageal squamous cell carcinoma growth in vitro and in vivo by targeting MEK1/2 kinase

Esophageal squamous cell carcinoma (ESCC) accounts for 90% of esophageal cancers and has a high mortality rate worldwide. The 5-year survival rate of ESCC patients in developing countries is <20%. Hence, there is an urgent need for developing new and effective treatments that are based on newly-discovered emerging molecules and pathways to prevent ESCC occurrence and recurrence. We investigated the effects of Daurisoline, a bis-benzylisoquinoline alkaloid extracted from the rhizome of menisperum dauricum, on ESCC cell proliferation and elucidated the molecular mechanisms underlying its functions. To explore the effects of Daurisoline on ESCC growth in vitro and in vivo, cell proliferation assays and anchorage-independent growth assays were performed and a patient-derived xenograft (PDX) model was established. Subsequently, phosphoproteomics, molecular docking analysis, pull down assays, mutation experiments and in vitro kinase assay were performed to explore the mechanism of Daurisoline's function on ESCC. Daurisoline inhibited ESCC proliferation in vitro and reduced ESCC PDX exnograft growth in vivo by reducing ERK1/2 phosphorylation. Furthermore, it directly bound to MEK1 (at Asn78 and Lys97) and MEK2 (at Asp194 and Asp212) kinases to inactivate the ERK1/2 signaling pathway. Our results suggest that Daurisoline is a dual inhibitor of MEK1 and MEK2 and suppresses ESCC growth both in vitro and in vivo by inactivating the ERK1/2 signaling pathway. This is first report on the use of MEK inhibitor for ESCC and highlights its potential applications for ESCC treatment and prevention.

Phosphorylation of AKT by lysyl oxidase-like 2 activates the PI3K/AKT signaling pathway to promote proliferation, invasion and metastasis in esophageal squamous carcinoma

OBJECTIVE

Esophageal squamous cell carcinoma (ESCC) is a common and aggressive malignancy of the gastrointestinal tract for which therapeutic options are scarce. This study screens for LOXL2, a key gene in ESCC, and explains the molecular mechanism by which it promotes the progression of ESCC.

METHODS

Immunohistochemical staining was performed to detect the expression level of LOXL2 in ESCC tissues and paraneoplastic tissues. CCK-8 and Transwell assays were performed to assess the effects of LOXL2 knockdown and overexpression on the proliferation, apoptosis, migration and invasion ability of ESCC cells. High-throughput sequencing analysis screens for molecular mechanisms of action by which LOXL2 promotes ESCC progression. Western blotting and qRT-PCR were used to determine the expression levels of relevant markers.

RESULTS

LOXL2 is positively expressed in ESCC and highly correlated with poor prognosis. Silencing LOXL2 significantly inhibited the proliferation, migration and invasive ability of ESCC cells, whereas overexpression showed the opposite phenotype. High-throughput sequencing suggested that LOXL2-associated differentially expressed genes were highly enriched in the PI3K/AKT signaling pathway. In vitro cellular assays confirmed that silencing LOXL2 significantly reduced PI3K, p-AKT^Thr308 and p-AKT^Ser473 gene and protein expression levels, while overexpression increased all three gene and protein levels, while AKT gene and protein expression levels were not significantly different.

CONCLUSION

This study found that LOXL2 may regulate the PI3K/AKT signaling pathway and exert protumor effects on ESCC cells through phosphorylation of AKT. LOXL2 may be a key clinical warning biomarker or therapeutic target for ESCC.

PHLDA3 activated by BARX2 transcription, suppresses the malignant development of esophageal squamous cell carcinoma by downregulating PI3K/AKT levels

BACKGROUND

Low pleckstrin homology-like domain family A, member 3 (PHLDA3) expression has been reported to be associated with cancer specificity and disease-free survival in esophageal squamous cell carcinoma (ESCC), and was an independent predictor of postoperative recurrence. However, the specific mechanisms involved are still unclear. This paper aimed to explore the role and its mechanisms of PHLDA3 in ESCC.

MATERIALS AND METHODS

PHLDA3 and BarH-like homeobox 2 (BARX2) expressions in ESCC were predicted by Gene Expression Profiling Interactive Analysis (GEPIA) analysis and determined by quantitative real-time polymerase chain reaction (qRT-PCR) and western Blot. Western blot detected the expression of proteins associated with migration, angiogenesis and phosphoinositide 3-kinase (PI3K)/protein kinase B (PKB/AKT) signaling pathway. The University of California Santa Cruz Genomics Institute (UCSC) database predicted that the relationship of BARX2 and PHLDA3 promoter and JASPAR identified the possible binding sites. Dual luciferase gene reporter verified PHLDA3 promoter activity, and the relationship of both was determined by chromatin immunoprecipitation (CHIP). Cell counting kit (CCK)-8, 5-ethynyl-2'-deoxyuridine (EDU) and colony formation were used to assess cell proliferation. Wound healing and transwell were used to detect cell migration and invasion ability. Tube formation assay was applied to assess angiogenesis. Mice were injected with transfected KYSE30 cells under the right axilla. Body weight and tumor volume and mass were recorded for each group of mice. Immunohistochemistry was performed to detect KI67 level in tumor tissues.

RESULTS

Both PHLDA3 and BARX2 were downregulated in ESCC. The upregulated PHLDA3 suppressed PI3K/AKT expression. In addition, BARX2 bound to the PHLDA3 promoter and transcriptionally activated PHLDA3. PHLDA3 overexpression inhibited ESCC cell proliferation, migration, invasion and angiogenesis, but this effect was reversed by BARX2 knockdown. In addition, BARX2 overexpression inhibited ESCC cell proliferation, migration, invasion and angiogenesis, but this effect was reversed by PHLDA3 knockdown.

CONCLUSION

PHLDA3 was transcriptionally activated by BARX2 and inhibited malignant progression of ESCC by downregulating PI3K/AKT levels.

Construction of a prognostic model for radical esophagectomy based on immunohistochemical prognostic markers combined with clinicopathological factors

Esophageal squamous cell carcinoma (ESCC) has a poor prognosis and lacks effective biomarkers to evaluate prognosis and treatment. Glycoprotein nonmetastatic melanoma protein B (GPNMB) is a protein highly expressed in ESCC tissues screened by isobaric tags for relative and absolute quantitation proteomics, which has significant prognostic value in a variety of malignant tumors, but its relationship with ESCC remains unclear. By immunohistochemical staining of 266 ESCC samples, we analyzed the relationship between GPNMB and ESCC. To explore how to improve the ability of ESCC prognostic assessment, we established a prognostic model of GPNMB and clinicopathological features. The results suggest that GPNMB expression is generally positive in ESCC tissues and is significantly associated with poorer differentiation, more advanced American Joint Council on Cancer (AJCC) stage, and higher tumor aggressiveness (P < .05). Multivariate Cox analysis indicated that GPNMB expression was an independent risk factor for ESCC patients. A total of 188 (70%) patients were randomly selected from the training cohort and the four variables were automatically screened by stepwise regression based on the AIC principle: GPNMB expression, nation, AJCC stage and nerve invasion. Through the weighted term, we calculate the risk score of each patient, and by drawing the receiver operating characteristic curve, we show that the model has good prognostic evaluation performance. The stability of the model was verified by test cohort. Conclusion: GPNMB is a prognostic marker consistent with the characteristics of tumor therapeutic targets. For the first time, we constructed a prognostic model combining immunohistochemical prognostic markers and clinicopathological features in ESCC, which showed higher prognostic efficacy than AJCC staging system in predicting the prognosis of ESCC patients in this region.

Clinical-Pathological Characteristics of Adenosquamous Esophageal Carcinoma: A Propensity-Score-Matching Study

There are few studies on esophageal adenosquamous carcinoma (ADSC). Our study intended to investigate the clinical and survival features of ADSC. We included esophageal cancer (EC) data from the Surveillance, Epidemiology, and End Results program database to explore clinical and survival traits. Propensity score matching (PSM), the multivariate Cox regression model, and survival curves were used in this study. A total of 137 patients with ADSC were included in our analysis. The proportion of ADSC within the EC cohort declined from 2004 to 2018. Besides, results indicated no significant difference in survival between ADSC and SCC groups (PSM-adjusted HR = 1.249, P = 0.127). However, the survival rate of the ADSC group was significantly worse than that of the ADC group (PSM-adjusted HR = 1.497, P = 0.007). For the ADSC group, combined treatment with surgery had a higher survival rate than other treatment methods (all P < 0.001). Surgical resection, radiotherapy, and chemotherapy were independent protective prognostic factors (all P < 0.05). The proportion of ADSC has been declining from 2004 to 2018. The prognosis of ADSC is not significantly different from that of SCC but is worse than that of ADC. Surgery, radiotherapy, and chemotherapy could improve the prognosis of patients. Comprehensive treatment with surgery as the main treatment is more beneficial for some patients.

Effect of esophageal cancer screening on mortality among patients with oral cancer and second primary esophageal cancer in Taiwan

OBJECTIVE

Oral and esophageal cancer are the fourth and fifth leading causes of cancer deaths among men in Taiwan. Despite a good prognosis for oral cavity cancer patients, survival is worse for those who develop second primary esophageal cancer. There remains no consensus regarding early prevention of potential second primary esophageal cancer in patients with oral cavity cancer. Our study aimed to compare 5-year mortality between endoscopically screened and non-screened patients with oral cavity cancer and second primary esophageal cancer.

MATERIALS AND METHODS

This study identified patients with incident oral cavity cancer and second primary esophageal cancer during 2004 and 2013 using the Taiwan Cancer Registry and National Health Insurance Research Database. We compared 5-year mortality from the second primary esophageal cancer diagnosis date between screened and non-screened groups of patients with oral cavity cancer and second primary esophageal cancer.

RESULTS

A total of 217 screened and 305 non-screened oral cavity cancer patients with second primary esophageal cancer were studied. Endoscopic screening significantly improved early detection of second primary esophageal cancer (adjusted odds ratio: 0.34, 95 % confidence interval [CI]: 0.23-0.49) and reduced all-cause mortality (adjusted hazard ratio: 0.80; 95 % CI: 0.66-0.98).

CONCLUSIONS

Oral cavity cancer patients with second primary esophageal cancer may have worse overall survival than those without. Early detection of second primary esophageal cancer is a crucial mediator between endoscopic screening and mortality. Endoscopic screening after the diagnosis of incident oral cavity cancer significantly increased early detection and reduced all-cause mortality.

Long intergenic non-protein coding RNA 00858 participates in the occurrence and development of esophageal squamous cell carcinoma through the activation of the FTO-m6A-MYC axis by recruiting ZNF184

OBJECTIVES

We aimed at probing impact of LINC00858 on esophageal squamous cell carcinoma (ESCC) progression via ZNF184-FTO-m⁶A-MYC axis.

METHODS

Expression of related genes (LINC00858, ZNF184, FTO, and MYC) was detected in ESCC tissues or cells and their relationships were assessed. After expression alterations in ESCC cells, cell proliferation, invasion, migration, and apoptosis were detected. Tumor formation in nude mice was conducted.

RESULTS

LINC00858, ZNF184, FTO, and MYC were overexpressed in ESCC tissues and cells. LINC00858 enhanced ZNF184 expression to upregulate FTO, which augmented MYC expression. LINC00858 knockdown diminished ESCC cell proliferative, migratory, and invasive properties while elevating apoptosis, which was negated by FTO overexpression. FTO knockdown exerted similar functions of LINC00858 knockdown on ESCC cell movements, which was annulled by MYC upregulation. Silencing LINC00858 repressed tumor growth and related gene expression in nude mice.

CONCLUSIONS

LINC00858 modulated MYC m⁶A modification via FTO by recruiting ZNF184, thus facilitating ESCC progression.

Global trends in the burden of esophageal cancer, 1990-2019: results from the Global Burden of Disease Study 2019

Background

Esophageal cancer is one of the leading causes of cancer death worldwide. A deeper understanding of the trends in annual incidence, mortality, and disability-adjusted life-years (DALYs) of esophageal cancer is critical for management and prevention. In this study, we report on the disease burden of esophageal cancer in 204 countries and territories between 1990 and 2019 by age, sex, and sociodemographic index (SDI).

Methods

Data on incidence, mortality, and DALYs were extracted from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019. The estimated numbers and age-standardized rates for esophageal cancer in 2019 are presented in this paper, as well as trends from 1990 to 2019. All estimates are presented as counts and age-standardized rates per 100,000 population, with 95% uncertainty intervals (UIs) for each estimate.

Results

In 2019, nearly 535,000 (95% UI: 467,000-595,000) new cases of esophageal cancer occurred globally. Esophageal cancer was responsible for more than 498,000 (95% UI: 438,000-551,000) deaths and 11.7 million (95% UI: 10.4-12.9 million) DALYs. Worldwide age-standardized rates of esophageal cancer, including incidence, deaths, and DALYs, have declined since 1990. However, the trends differ across countries and territories. Notably, there was a nonlinear but generally inverse correlation between age-standardized DALY rates and SDI. Higher age-standardized incidence and death rates were observed in males compared to females, and both increased with age. Regarding risk factors, smoking, alcohol use, and high body-mass index were 3 predominant contributors to esophageal cancer DALYs in 2019 for both sexes worldwide.

Conclusions

This study found a global reduction in the esophageal cancer burden, but substantial heterogeneity remains across regions and countries. Hence, the identification of high-risk groups and the exploration of specific local strategies and primary prevention efforts are required.

Wnt signaling pathway-related gene PRICKLE1 is a prognostic biomarker for esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) has become a major health risk to human health. Although significant clinical progress has been made in the treatment of ESCC, the prognosis of patients still needs to be improved. Therefore, it is important to screen effective molecular indicators for the prognosis of ESCC. In this study, the intersection of up-regulated genes, down-regulated genes, and Wnt signaling pathway-related genes in ESCC was taken, and 47 overlapping genes were found. PRICKLE1 was determined to be an independent prognostic factor in ESCC based on univariate and multifactorial COX risk regression models. Kaplan-Meier survival curves showed that patients in the PRICKLE1 high expression group had significantly better overall survival. In addition, we performed various experiments to examine the effects of PRICKLE1 overexpression on proliferation, migration, and apoptosis of ESCC cells. The experimental results showed that the PRICKLE1-OE group had reduced cell viability, significantly lower migration ability and significantly higher apoptosis rate compared to the NC group.Therefore, we hypothesized that high PRICKLE1 expression could be used to predict the survival rate of ESCC patients, which could be used as an independent prognostic indicator for ESCC patients and provide potential applications for ESCC clinical treatment.

Dasabuvir suppresses esophageal squamous cell carcinoma growth in vitro and in vivo through targeting ROCK1

Esophageal squamous cell carcinoma (ESCC) is an upper gastrointestinal cancer with high morbidity and mortality. New strategies are urgently needed to prolong patients' survival. Through screening FDA-approved drugs, we found dasabuvir, a drug approved for hepatitis C virus (HCV) treatment, suppressed ESCC proliferation. Dasabuvir could inhibit the growth of ESCC cells in a time and dose-dependent manner and arrested cell cycle at the G0/G1 phase. The antitumor activity was further validated in vivo using patient-derived xenograft tumor models. In terms of mechanism, we unveil that dasabuvir is a Rho-associated protein kinase 1 (ROCK1) inhibitor. Dasabuvir can bind to ROCK1 and suppress its kinase activity, thus downregulating the phosphorylation of ERK1/2 by ROCK1 and the expression of cyclin-dependent kinase 4 (CDK4) and cyclin D1. These results provide evidence that dasabuvir suppresses ESCC growth in vivo and in vitro through blocking ROCK1/ERK signaling pathway.

Associations of mitochondrial DNA copy number with incident risks of gastrointestinal cancers: A prospective case-cohort study

Epidemiological investigations implied that mitochondrial DNA copy number (mtDNAcn) variations could trigger predisposition to multiple cancers, but evidence regarding gastrointestinal cancers (GICs) was still uncertain. We conducted a case-cohort study within the prospective Dongfeng-Tongji cohort, including incident cases of colorectal cancer (CRC, n = 278), gastric cancer (GC, n = 138), and esophageal cancer (EC, n = 72) as well as a random subcohort (n = 1173), who were followed up from baseline to the end of 2018. We determined baseline blood mtDNAcn and associations of mtDNAcn with the GICs risks were estimated by using weighted Cox proportional hazards models. Significant U-shaped associations were observed between mtDNAcn and GICs risks. Compared to subjects within the second quartile (Q2) mtDNAcn subgroup, those within the 1st (Q1), 3rd (Q3), and 4th (Q4) quartile subgroups showed increased risks of CRC (hazard ratio [HR] [95% confidence interval, CI] = 2.27 [1.47-3.52], 1.65 [1.04-2.62], and 2.81 [1.85-4.28], respectively) and total GICs (HR [95%CI] = 1.84 [1.30-2.60], 1.47 [1.03-2.10], and 2.51 [1.82-3.47], respectively], and those within Q4 subgroup presented elevated GC and EC risks (HR [95% CI] = 2.16 [1.31-3.54] and 2.38 [1.13-5.02], respectively). Similar associations of mtDNAcn with CRC and total GICs risks remained in stratified analyzes by age, gender, smoking, and drinking status. This prospective case-cohort study showed U-shaped associations between mtDNAcn and GICs risks, but further research works are needed to uncover underlying biological mechanisms.

Reciprocal regulation of LINC00941 and SOX2 promotes progression of esophageal squamous cell carcinoma

LINC00941 is a novel long noncoding RNA (lncRNA) and emerging as an important factor in cancer development. However, the exact function and relative regulatory mechanism of LINC00941 in carcinogenesis of esophageal squamous cell carcinoma (ESCC) remain to be further clarified. The present study was to investigate the expression level, functions, and mechanisms of LINC00941 in ESCC tumorigenesis. LINC00941 was significantly upregulated in ESCC, and upregulated LINC00941 was correlated with dismal patient outcomes. LINC00941 functioned as an oncogene by promoting cells proliferation, stemness, migration, and invasion in ESCC. In terms of mechanisms, SOX2 could bind directly to the promoter region of LINC00941 and activate its transcription. In turn, LINC00941 upregulated SOX2 through interacting with interleukin enhancer binding factor 2 (ILF2) and Y-box binding protein 1 (YBX1) at the transcriptional and post-transcriptional levels. LINC00941 recruited ILF2 and YBX1 to the promoter region of SOX2, leading to upregulation of the transcription of SOX2. Moreover, LINC00941 could promote the binding ability of ILF2 and YBX1 on mRNA of SOX2 and further stabilize SOX2 mRNA. Therefore, LINC00941 contributed to the malignant behaviors of ESCC cells via the unrestricted increase in SOX2 expression. In conclusion, our data indicate that LINC00941 exacerbates ESCC progression through forming a LINC00941-ILF2/YBX1-SOX2 positive feedback loop, and LINC00941 may be a promising prognostic and therapeutic target for ESCC.

Research Progress on the Predicting Factors and Coping Strategies for Postoperative Recurrence of Esophageal Cancer

Esophageal cancer is one of the malignant tumors with poor prognosis in China. Currently, the treatment of esophageal cancer is still based on surgery, especially in early and mid-stage patients, to achieve the goal of radical cure. However, esophageal cancer is a kind of tumor with a high risk of recurrence and metastasis, and locoregional recurrence and distant metastasis are the leading causes of death after surgery. Although multimodal comprehensive treatment has advanced in recent years, the prediction, prevention and treatment of postoperative recurrence and metastasis of esophageal cancer are still unsatisfactory. How to reduce recurrence and metastasis in patients after surgery remains an urgent problem to be solved. Given the clinical demand for early detection of postoperative recurrence of esophageal cancer, clinical and basic research aiming to meet this demand has been a hot topic, and progress has been observed in recent years. Therefore, this article reviews the research progress on the factors that influence and predict postoperative recurrence of esophageal cancer, hoping to provide new research directions and treatment strategies for clinical practice.

Esophageal Squamous Cancer from 4NQO-Induced Mice Model: CNV Alterations

Squamous esophageal carcinoma is a common pathological type of esophageal carcinoma around the world. The prognosis of esophageal carcinoma is usually poor and diagnosed at late stages. Recently, research suggested that genomic instability occurred in esophageal cells during the development of esophageal squamous cell carcinoma (ESCC). Identifying prognostic and specific genomic characteristics, especially at the early hyperplasia stage, is critical. Mice were given 4-nitroquinoline 1-oxide (4NQO) with drinking water to induce esophageal cancer. The immortalized human esophageal epithelial cell line (NE2) was also treated with 4NQO. We performed histologic analyses, immunofluorescence, and immunohistochemical staining to detect DNA damage at different time points. Whole-exome sequencing was accomplished on the esophagus tissues at different pathological stages to detect single-nucleotide variants and copy number variation (CNV) in the genome. Our findings indicate that all mice were tumor-forming, and a series of changes from simple hyperplasia (ESSH) to intraepithelial neoplasia (IEN) to esophageal squamous cell carcinoma (ESCC) was seen at different times. The expression of γ-H2AX increased from ESSH to ESCC. In addition, mutations of the Muc4 gene were detected throughout the pathological stages. Furthermore, CNV burden appeared in the esophageal tissues from the beginning of ESSH and accumulated more in cancer with the deepening of the lesions. This study demonstrates that mutations caused by the early appearance of DNA damage may appear in the early stage of malignant tissue before the emergence of atypia. The detection of CNV and mutations of the Muc4 gene may be used as an ultra-early screening indicator for esophageal cancer.

Aberrant NSG1 Expression Promotes Esophageal Squamous Cell Carcinoma Cell EMT by the Activation of ERK Signaling Pathway

BACKGROUND

Neuron-specific gene family member 1 (NSG1) is a 21 kDa endosomal protein that is specifically expressed in neurons.

AIMS

This study was to explore the expression of NSG1 and possible mechanism in Esophageal Squamous Cell Carcinoma (ESCC).

METHODS

The Cancer Genome Atlas (TCGA) database was consulted to analyze the expression of NSG1 in ESCC. Immunohistochemistry (IHC) staining was used to evaluate NSG1 expression in ESCC cancerous tissues and matched paracancerous tissues. The CCK-8 assay, wound-healing assay, and transwell assay were used to detect the cell viability, migration, and invasion of ESCC cells. Western blot was used to assay epithelial-mesenchymal transition (EMT)-related proteins and ERK signaling pathway protein expression.

RESULTS

The results showed that the expression of NSG1 in ESCC cancerous tissues was higher than noncancerous tissues. Compared with negative control (NC) group, cell viability, migration. and invasion significantly increased, the expression of p-ERK in ERK signaling pathway was significantly upregulated, the expressions of mesenchymal marker Vimentin and EMT-related transcription factors including snail and slug were significantly upregulated, and the expression of epithelial marker E-cadherin was significantly downregulated in KYSE-150 cells with NSG1 overexpression. However, these effects were reversed by the ERK signaling pathway inhibitor U0126. On the other hand, TE-1 cells with NSG1 knockdown had the changes contrary to that in KYSE-150 cells with NSG1 overexpression.

CONCLUSION

NSG1 plays a potential carcinogenic role on the occurrence and progression of ESCC, and aberrant NSG1 expression might promote ESCC cell EMT by the activation of ERK signaling pathway.

Identification of Tumor Suppressor Gene LHPP-Based 5-microRNA Signature That Predicts the Early- and Midstage Esophageal Squamous Cell Carcinoma: A Two-Stage Case-Control Study in the Chinese Han Population

Objective

To establish a novel approach for diagnosing early- and midstage esophageal squamous cell carcinoma (ESCC).

Methods

The tumor suppressor gene phospholysine phosphohistidine inorganic pyrophosphate phosphatase (LHPP)–based miRNA signature was identified using next-generation sequencing and 3 biological online prediction systems. This retrospective study established and validated an ESCC prediction model using a test cohort and a validation cohort.

Results

Immunohistochemical staining and real-time quantitative polymerase chain reaction (RT-qPCR) results showed that LHPP protein levels were significantly lower in tissues with early- and midstage ESCC than in adjacent tissues (P &lt; .01). Further, we confirmed that miR-15b-5p, miR-424-5p, miR-497-5p, miR-363-5p, and miR-195-5p inhibited LHPP. These 5 miRNAs were significantly elevated in the plasma of early- and midstage ESCC (P &lt; .05). An ESCC prediction model combining these 5 miRNAs was established. Finally, in the external validation cohort, the model exhibited high discriminative value (sensitivity/specificity: 84.4%/93.3%).

Conclusions

The prediction model has potential implications for diagnosis of early- and midstage ESCC.

Identification of natural product 3, 5-diiodotyrosine as APOBEC3B inhibitor to prevent somatic mutation accumulation and cancer progression

BACKGROUND

The development of cancer is largely dependent on the accumulation of somatic mutations, indicating the potential to develop cancer chemoprevention agents targeting mutation drivers. However, ideal cancer chemoprevention agents that can effectively inhibit the mutation drivers have not been identified yet.

METHODS

The somatic mutation signatures and expression analyses of APOBEC3B were performed in patient with pan-cancer. The computer-aided screening and skeleton-based searching were performed to identify natural products that can inhibit the activity of APOBEC3B. 4-nitroquinoline-1-oxide (4-NQO)-induced spontaneous esophageal squamous cell carcinoma (ESCC) and azoxymethane/dextran sulfate sodium (AOM/DSS)-induced spontaneous colon cancer mouse models were conducted to investigate the influences of APOBEC3B inhibitor on the prevention of somatic mutation accumulation and cancer progression.

RESULTS

Here, we discovered that the cytidine deaminase APOBEC3B correlated somatic mutations were widely observed in a variety of cancers, and its overexpression indicated poor survival. SMC247 (3, 5-diiodotyrosine), as a source of kelp iodine without side effects, could strongly bind APOBEC3B (K_D=65 nM) and effectively inhibit its deaminase activity (IC₅₀=1.69 µM). Interestingly, 3, 5-diiodotyrosine could significantly reduce the clusters of mutations, prevent the precancerous lesion progression, and prolong the survival in 4-NQO-induced spontaneous ESCC and AOM/DSS-induced spontaneous colon cancer mouse models. Furthermore, 3, 5-diiodotyrosine could reduce colitis, increase the proportion and function of T lymphocytes via IL-15 in tumor microenvironment. The synergistic cancer prevention effects were observed when 3, 5-diiodotyrosine combined with PD-1/PD-L1 blockade.

CONCLUSIONS

This is the first prove-of-concept study to elucidate that the natural product 3, 5-diiodotyrosine could prevent somatic mutation accumulation and cancer progression through inhibiting the enzymatic activity of APOBEC3B. In addition, 3, 5-diiodotyrosine could reduce the colitis and increase the infiltration and function of T lymphocytes via IL-15 in tumor microenvironment. 3, 5-diiodotyrosine combined with PD-1/PD-L1 blockade could elicit synergistic cancer prevention effects, indicating a novel strategy for both prevent the somatic mutation accumulation and the immune-suppressive microenvironment exacerbation.

Anti-CXCL8 Autoantibody: A Potential Diagnostic Biomarker for Esophageal Squamous Cell Carcinoma

Background and Objectives: Esophageal squamous cell carcinoma (ESCC) is one of the most common malignancies. Anti-tumor associated antigen autoantibodies (TAAbs) can be used as biomarkers for tumor detection. The aim of this study was to identify a reliable TAAb as the diagnostic marker for ESCC. Materials and Methods: The Cancer Genome Atlas (TCGA) database was used to screen candidate genes. The mRNA expression of the key gene was then verified by micro array dataset GSE44021 from the Gene Expression Omnibus (GEO) database and the diag nostic value of the corresponding autoantibody to the key gene in ESCC was detected by enzyme-linked im muno sorbent assay (ELISA). Results: CXCL8 was identified as the key gene. The dataset GSE44021 showed that CXCL8 mRNA expression was prominently over-expressed in ESCC tissues compared with normal tissues. ELISA results showed that the level of anti-CXCL8 autoantibody in ESCC patients was significantly higher than in normal controls and the receiver operating char ac teristic (ROC) curve indicated that anti-CXCL8 autoantibody could discriminate ESCC patients from normal controls, with the area under the ROC curve (AUC) for the verification cohort, and the validation cohort were 0.713 and 0.751, respectively. Conclusions: Our study illustrated that anti-CXCL8 autoantibody had good diagnostic value, and may become a candidate biomarker for ESCC.

LncRNA SNHG3 promoted cell proliferation, migration, and metastasis of esophageal squamous cell carcinoma via regulating miR-151a-3p/PFN2 axis

Esophageal squamous cell carcinoma (ESCC) is an aggressive malignant tumor with a poor prognosis. The dysregulation of long non-coding RNAs (lncRNAs) is closely related to the tumorigenesis and progression of ESCC. However, the effects of lncRNA small nucleolar RNA host gene 3 (lncRNA SNHG3) in ESCC are still unclear. Therefore, a series of experiments methods, such as quantitative real-time polymerase chain reaction, function gain/loss experiments, western blots, and animal xenograft tumor model, were employed to explore the biological function and molecular mechanism of SNHG3 in ESCC. As results, we first reported that SNHG3 was significantly up-regulated in ESCC tissues and cells. SNHG3 knockdown obviously inhibited cell proliferation, migration, invasion, and promoted apoptosis. Mechanism analysis revealed that SNHG3 sponged miR-151a-3p to regulate PFN2. Inhibition of miR-151a-3p and overexpression of PFN2 attenuated the positive effect of SNHG3 knockdown on suppressing tumor progression. Furthermore, the anti-tumor effects of SNHG3 knockdown were also observed in vivo. In summary, our results indicated that SNHG3 knockdown suppressed tumor development via the miR-151a-3p/PFN2 axis, and targeting SNHG3 may provide a new opportunity for ESCC patients.

Allicin promotes autophagy and ferroptosis in esophageal squamous cell carcinoma by activating AMPK/mTOR signaling

The antitumor effects of allicin have been demonstrated in various cancers. However, whether allicin improves esophageal squamous cell carcinoma (ESCC) has not yet been explored. The present study aimed to explore the function and underlying mechanism of action of allicin in ESCC treatment. Our data showed that allicin significantly suppressed ESCC cell proliferation in a dose- and time-dependent manner. A green fluorescent protein-light chain 3 (LC3) transfection assay showed that autophagosomes were elevated in ESCC cells treated with allicin compared with control ESCC cells and that 3-methyladenine (an autophagy inhibitor) reversed allicin-induced LC3 puncta. Furthermore, allicin significantly elevated the ratio of LC3II/LC3I but decreased p62 expression in ESCC cells. Allicin also increased adenosine monophosphate-activated protein kinase (AMPK) phosphorylation but decreased that of the mechanistic target of rapamycin kinase (mTOR), which then induced the elevation of autophagy-related 5 and autophagy-related 7 proteins in ESCC cells. Furthermore, allicin treatment increased the expression of nuclear receptor coactivator 4 (a selective cargo receptor) but suppressed the expression of ferritin heavy chain 1 (the major intracellular iron-storage protein) in ESCC cells and elevated malondialdehyde and Fe2+ production levels. In vivo assays showed that allicin significantly decreased tumor weight and volume. In summary, allicin may induce cell death in ESCC cells by activating AMPK/mTOR-mediated autophagy and ferroptosis. Therefore, allicin may have excellent potential for use in the treatment of ESCC.

Ferroptosis and its emerging role in esophageal cancer

The occurrence and development of tumors involve a series of life activities of cells, among which cell death has always been a crucial part in the research of tumor mechanisms and treatment methods. Ferroptosis is a non-apoptotic form of cell death, which is characterized by lipid peroxidation accumulation and further cell membrane rupture caused by excessive production of intracellular oxygen free radicals dependent on iron ions. Esophageal cancer is one of the common digestive tract tumors. Patients in the early stage are mainly treated with surgery, and the curative effect is awe-inspiring. However, surgery is far from enough for terminal patients, and it is the best choice to combine radiotherapy and chemotherapy before the operation or during the perioperative period. Although the treatment plan for patients with advanced esophageal cancer is constantly being optimized, we are disappointed at the still meager 5-year survival rate of patients and the poor quality of life. A series of complex problems, such as increased chemotherapy drug resistance and decreased radiotherapy sensitivity of esophageal cancer cells, are waiting for us to tackle. Perhaps ferroptosis can provide practical and feasible solutions and bring new hope to patients with advanced esophageal cancer. The occurrence of ferroptosis is related to the dysregulation of iron metabolism, lipid metabolism, and glutamate metabolism. Therefore, these dysregulated metabolic participant proteins and signaling pathways are essential entry points for using cellular ferroptosis to resist the occurrence and development of cancer cells. This review first introduced the main regulatory mechanisms of ferroptosis. It then summarized the current research status of ferroptosis in esophageal cancer, expecting to provide ideas for the research related to ferroptosis in esophageal cancer.

Circular RNA hsa_circ_0003823 promotes the Tumor Progression, Metastasis and Apatinib Resistance of Esophageal Squamous Cell Carcinoma by miR-607/CRISP3 Axis

Background: Circular RNAs (CircRNAs) have attracted a growing interest of research in cancer. The regulatory roles and mechanisms of circRNAs in progression, metastasis and drug resistance of esophageal squamous cell carcinoma (ESCC) needed to be clarified. Our previous study revealed the crucial role of Apatinib in ESCC therapy. However, the correlation between circRNAs and Apatinib resistance remained unclear. Methods: 3 pairs of tumor and paracancerous tissues of ESCC patients were used for RNA sequencing. Western blot analysis, RNA immunoprecipitation (RIP), dual-luciferase reporter assays, apoptosis and animal assays were conducted to confirm the roles and specific mechanisms of hsa_circ_0003823 as well as the effects of it on Apatinib sensitivity in ESCC. Results: Our results revealed that hsa_circ_0003823 was highly expressed in ESCC and associated with poor prognosis. Further results indicated that hsa_circ_0003823 promoted proliferation and metastasis ability of ESCC. In the section of mechanism experiments, hsa_circ_0003823 regulated CRISP3 by targeting microRNA-607 (miR-607) to promote progression of ESCC. Besides, we found that silencing hsa_circ_0003823 improved Apatinib sensitivity. hsa_circ_0003823 resulted in Apatinib resistance by miR-607/CRISP3 axis. Conclusions: In this study, we elucidated the function of hsa_circ_0003823 and its role in promoting tumor progression, metastasis and Apatinib resistance of ESCC through miR-607/CRISP3 axis.

Untargeted serum metabolomics reveals potential biomarkers and metabolic pathways associated with esophageal cancer

Metabolomics has been reported as an efficient tool to screen biomarkers that are related to esophageal cancer. However, the metabolic biomarkers identifying malignant degrees and therapeutic efficacy are still largely unknown in the disease. Here, GC-MS-based metabolomics was used to understand metabolic alteration in 137 serum specimens from patients with esophageal cancer, which is approximately two- to fivefold as many plasma specimens as the previous reports. The elevated amino acid metabolism is in sharp contrast to the reduced carbohydrate as a characteristic feature of esophageal cancer. Comparative metabolomics showed that most metabolic differences were determined between the early stage (0–II) and the late stage (III and IV) among the 0–IV stages of esophageal cancer and between patients who received treatment and those who did not receive treatment. Glycine, serine, and threonine metabolism and glycine were identified as the potentially overlapped metabolic pathway and metabolite, respectively, in both disease progress and treatment effect. Glycine, fructose, ornithine, and threonine can be a potential array for the evaluation of disease prognosis and therapy in esophageal cancer. These results highlight the means of identifying previously unknown biomarkers related to esophageal cancer by a metabolomics approach.

Upregulation of KIF18B facilitates malignant phenotype of esophageal squamous cell carcinoma by activating CDCA8/mTORC1 pathway

Background

Kinesin family member 18B (KIF18B) has been regarded as an oncogene that is abnormally overexpressed in some cancers, but its mechanism in esophageal squamous cell carcinoma (ESCC) remains unclear, which is thereby investigated in this study.

Methods

Bioinformatics analysis was performed to analyze the expression of KIF18B in esophageal carcinoma (ESCA). Quantitative real‐time polymerase chain reaction (qRT‐PCR) was used to detect KIF18B expression in ESCC cells. After KIF18B overexpression or cell division cycle associated 8 (CDCA8) deficiency, ESCC cells were subjected to determination of qRT‐PCR, Western blot, cell counting kit‐8 assay, flow cytometry, wound healing, and Transwell assay. The mechanism of KIF18B in the mechanistic target of rapamycin complex 1 (mTORC1) pathway was detected by Western blot.

Results

KIF18B was overexpressed in ESCA samples and ESCC cells. Upregulation of KIF18B enhanced the viability, accelerated cell cycle by elevating CDK4 and Cyclin D3 levels as well as promoted the migration and invasion by decreasing E‐cadherin level and increasing Vimentin and N‐cadherin levels in ESCC cells, which was counteracted by CDCA8 silencing. The expression of CDCA8 in ESCC cells was upregulated by KIF18B overexpression. KIF18B overexpression activated the mTORC1 pathway by upregulating phosphorylated (p)‐/p70S6K and p‐/mTOR levels in the ESCC cells, which was reversed by CDCA8 silencing.

Conclusion

KIF18B overexpression promotes the proliferation, migration, and invasion of ESCC cells via CDCA8‐mediated mTORC1 signaling pathway in vitro.

Combined Mean Corpuscular Hemoglobin, Fibrinogen, and Albumin (MF-A) Is a Novel Prognostic Marker in Patients with Resectable Esophageal Squamous Cell Carcinoma

BACKGROUND

The aim was to systematically select blood markers routinely tested in clinical settings, which are independently associated with overall survival (OS) and are able to stratify prognosis of esophageal squamous cell carcinoma (ESCC) patients undergoing esophagectomy.

METHODS

We selected optimal blood markers for prognostic stratification from 60 candidates in a clinical cohort of 1819 consecutive patients with resectable ESCC in China. Selection was carried out using two-step multivariable Cox proportional hazards regression adjusted for multifaceted confounders. A composite index was developed by multiplying risk factors and dividing them by protective factors.

RESULTS

With a median follow-up of 48.07 months, 641 deaths occurred in the 1819 patients and the 5-year OS was 56.30%. Two risk factors (mean corpuscular hemoglobin, fibrinogen) and a protective factor (albumin), all dichotomized and assigned values 1 and 2, were used to construct the composite index marker "MF-A". Three risk groups were created based on the MF-A score including low- (0.5), moderate- (1), and high-risk groups (2 and 4). Compared with patients in the low-risk group (1184/1778, 66.59%), those in the moderate- (488, 27.45%), and high-risk (106, 5.96%) groups were at elevated risk of death (adjusted HR: 1.32, 95% CI: 1.11-1.57; adjusted HR: 2.08, 95% CI: 1.56-2.75; P_trend < 10^-7). Within each TNM stage grouping, OS also trended to be significantly worse as the MF-A score increased.

CONCLUSIONS

"MF-A" is a novel independent predictor which may be used to estimate and stratify prognosis for ESCC patients undergoing esophagectomy.

Machine Learning and Novel Biomarkers Associated with Immune Infiltration for the Diagnosis of Esophageal Squamous Cell Carcinoma

Esophageal squamous cell carcinoma (ESCC) accounts for the main esophageal cancer type, which is related to advanced stage and poor survivals. Therefore, novel diagnostic biomarkers are critically needed. In the current research, we aimed to screen novel diagnostic biomarkers based on machine learning. The expression profiles were obtained from GEO datasets (GSE20347, GSE38129, and GSE75241) and TCGA datasets. Differentially expressed genes (DEGs) were screened between 47 ESCC and 47 nontumor samples. The LASSO regression model and SVM-RFE analysis were carried out for the identification of potential markers. ROC analysis was carried out to assess discriminatory abilities. The expressions and diagnostic values of the candidates in ESCC were demonstrated in the GSE75241 datasets and TCGA datasets. We also explore the correlations between the critical genes and cancer immune infiltrates using CIBERSORT. In this study, we identified 27 DEGs in ESCC: 5 genes were significantly elevated, and 22 genes were significantly decreased. Based on the results of the SVM-RFE and LASSO regression model, we identified five potential diagnostic biomarkers for ESCC, including GPX3, COL11A1, EREG, MMP1, and MMP12. However, the diagnostic values of only GPX3, MMP1, and MMP12 were confirmed in GSE75241 datasets. Moreover, in TCGA datasets, we further confirmed that GPX3 expression was distinctly decreased in ESCC specimens, while the expression of MMP1 and MMP12 was noticeably increased in ESCC specimens. Immune cell infiltration analysis revealed that the expression of GPX3, MMP1, and MMP12 was associated with several immune, such as T cells CD8, macrophages M2, macrophages M0, and dendritic cells activated. Overall, our findings suggested GPX3, MMP1, and MMP12 as novel diagnostic marker and correlated with immune infiltrates in ESCC patients.

Similarities between wound re-epithelialization and Metastasis in ESCC and the crucial involvement of macrophages: A review

In cancer, tumor-associated macrophages (TAMs) possess crucial functions in facilitating epithelial-mesenchymal transition (EMT). EMT is a crucial process in tumor metastasis. Tumor metastasis is one of the hallmarks of cancer and leads to patient mortality. Cancer cells often find ways to evade being detected and attacked by the immune system. This is achieved by cross-talk between cancer cells and the altered microenvironment. The accumulation of tumor-associated macrophages (TAMs) in the tumor microenvironment (TME) creates an immunosuppressive and tumor-supportive environment. Circulating monocytes and macrophages which are recruited into tumors are defined as tumor-associated macrophages once in the TME. Based on the activated stimuli and function, macrophages can be divided into M1 macrophages and M2 macrophages. M1 macrophages, also known as classically activated macrophages, exhibit pro-inflammatory and antitumor activities. M2 macrophages, also known as alternatively activated macrophages, exhibit anti-inflammatory, pro-tumorigenic, and wound healing activities. TAMs are considered to be of the M2 phenotype. The TME polarizes recruited macrophages into M2 macrophages as they provide an immunosuppressive pro-tumoral environment. Accumulating studies show that the presence of TAMs in esophageal squamous cell carcinoma (ESCC) leads to tumor progression. In this review, we discuss how EMT can be used by TAMs to cause tumor migration and metastasis in ESCC. We also discuss the potential therapies targeting TAMs.

Performance of screening tests for esophageal squamous cell carcinoma: a systematic review and meta-analysis

BACKGROUND AND AIMS

This systematic review and meta-analysis aims to compare the pooled diagnostic accuracy of the currently available esophageal squamous cell carcinoma (ESCC) screening tests.

METHODS

A comprehensive literature search of Embase and Medline (up to October 31, 2020) was performed to identify eligible studies. We pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio for ESCC screening tools using a bivariate random-effects model. The summary receiver operating characteristic curves with area under the curve (AUC) were plotted for each screening test.

RESULTS

We included 161 studies conducted in 81 research articles involving 32,209 subjects. The pooled sensitivity, specificity, and AUC of the major screening tools were respectively as follows: endoscopy (peroral endoscopy): .94 (95% confidence interval [CI], .87-.97), .92 (95% CI, .87-.95), and .97 (95% CI, .96-.99); endoscopy (transnasal endoscopy): .85 (95% CI, .70-.93), .96 (95% CI, .91-.98), and .97 (95% CI, .95-.98); microRNA: .77 (95% CI, .75-.80), .78 (95% CI, .75-.80), and .85 (95% CI, .81-.87); autoantibody: .45 (95% CI, .36-.53), .91 (95% CI, .89-.93), and .84 (95% CI, .81-.87); and cytology: .82 (95% CI, .60-.93), .97 (95% CI, .88-.99), and .97 (95% CI, .95-.98). There was high heterogeneity.

CONCLUSIONS

The diagnostic accuracy seemed to be comparable between cytology and endoscopy, whereas autoantibody and microRNAs bear potential as future noninvasive screening tools for ESCC. To reduce ESCC-related death in high-risk populations, it is important to develop a more accurate and less-invasive screening test.

Management of Esophageal Cancer Treatment in Resource-Limited Settings

Due to the luminal nature of the disease, esophageal cancer diagnosis and treatment is challenging. Majority of the patients usually present with dysphagia, at which point the disease is often locally advanced. Diagnosis and treatment need a multidisciplinary approach which often involves endoscopy, imaging services, oncology services, surgical services, and critical care services. Surgery is associated with significant morbidity and mortality and care should be domiciled in high-volume centers. Training and mentorship are key to building capacity for esophageal cancer care.

Exosomal MicroRNA Analyses in Esophageal Squamous Cell Carcinoma Cell Lines

Exosomal miRNAs have been studied in various cancers as minimally invasive biomarkers. This study aimed to investigate the potential of exosomal microRNAs (miRNAs) as biomarkers for esophageal squamous cell carcinoma (ESCC). Exosomes were isolated from cultures of esophageal epithelial cell and ESCC cell lines using ExoDisc, and exosomal miRNAs were detected via miRNA sequencing. Of the differentially expressed 14 miRNAs, the top 2 up-regulated miRNAs (miR-205-5p and miR-429) and top 2 down-regulated miRNAs (miR-375-3p and miR-483-3p) were selected as ESCC target miRNAs. Four selected exosomal miRNAs were validated in the plasma of 20 healthy controls (HCs) and 40 ESCC patients via quantitative reverse transcription-polymerase chain reaction. The expression of plasma exosomal miR-205-5p and miR-429 significantly increased, while that of plasma exosomal miR-375-3p was significantly reduced in ESCC patients compared to that in HCs. At cut-off values of 5.04, 2.564, and 0.136, the sensitivity and specificity for the diagnosis of ESCC were 72.5% and 70.0% for miR-205-5p, 60.0% and 60.0% for miR-429, and 65.0% and 65.0% for miR-375-3p, respectively. Based on the exosomal miRNAs identified in ESCC cell lines, our study demonstrated that plasma exosomal miR-205-5p, miR-429, and miR-375-3p could serve as potential biomarkers for ESCC diagnosis.

Endoscopic Management of Esophageal Cancer

Advances in technology and improved understanding of the pathobiology of esophageal cancer have allowed endoscopy to serve a growing role in the management of this disease. Precursor lesions can be detected using enhanced diagnostic modalities and eradicated with ablation therapy. Furthermore, evolution in endoscopic resection has provided larger specimens for improved diagnostic accuracy and offer potential for cure of early esophageal cancer. In patients with advanced esophageal cancer, endoluminal therapy can improve symptom burden and provide therapeutic options for complications such as leaks, perforations, and fistulas. The purpose of this review article is to highlight the role of endoscopy in the diagnosis, treatment, and palliation of esophageal cancer.

A novel circ_0000654/miR-375/E2F3 ceRNA network in esophageal squamous cell carcinoma

Background

The competing endogenous RNA (ceRNA) activity of circular RNAs (circRNAs) has been implicated in the pathogenesis of cancers, including esophageal squamous cell carcinoma (ESCC). Here, we identified the ceRNA mechanism of circ_0000654 regulation in ESCC.

Methods

The levels of circ_0000654, E2F transcription factor 3 (E2F3), and microRNA (miR)‐375 were gauged by quantitative real‐time PCR (qRT‐PCR) and western blot. Cell proliferation was assessed by 3‐(4,5‐dimethylthiazol‐2‐yl)‐5‐(3‐carboxymethoxyphenyl)‐2‐(4‐sulfophenyl)‐2H‐tetrazolium (MTS) and 5‐ethynyl‐2′‐deoxyuridine (EdU) assays. Cell apoptosis was detected by flow cytometry. Cell colony formation was tested by colony formation assay. Dual‐luciferase reporter, RNA pull‐down and RNA immunoprecipitation (RIP) assays were performed to confirm the direct relationship between miR‐375 and circ_0000654 or E2F3. Xenograft model assays were used to evaluate the effect of circ_0000654 in vivo.

Results

Circ_0000654 and E2F3 were upregulated in ESCC. Circ_0000654 depletion enhanced cell apoptosis and hindered cell proliferation and glycolysis in vitro, as well as weakened tumor growth in vivo. Increased expression of E2F3 counteracted the effects of circ_0000654 depletion. Mechanistically, E2F3 was a target of miR‐375, and circ_0000654 modulated E2F3 expression through sequestering miR‐375. Furthermore, miR‐375 upregulation phenocopied circ_0000654 knockdown in inhibiting ESCC progression.

Conclusion

Our findings identify a new circ_0000654/miR‐375/E2F3 ceRNA crosstalk for the oncogenic role of circ_0000654 in ESCC and establish a notion that targeting circ_0000654 and its pathways may have the potential to improve ESCC outcome.

LINC00667 Promotes Progression of Esophageal Cancer Cells by Regulating miR-200b-3p/SLC2A3 Axis

BACKGROUND

Recently, more and more evidence indicated that the long non-coding RNA was strictly related to the occurrence and progression of human cancers, including esophageal cancer (EC). We observed that LINC00667 was increased in EC, but the function of LINC00667 was unclear. Therefore, the function and potential molecular mechanism of LINC00667 in the progression of EC need to be further studied.

METHODS

Quantitative real-time PCR was used to investigate the levels of LINC00667, miR-200b-3p, and SLC2A3. The levels of protein involved in cell cycle, cell apoptosis, epithelial-mesenchymal transition, as well as SLC2A3 were quantitatived by western blot. The role of LINC00667 in the proliferative, migratory and invasive capabilities of EC cells were measured by cell counting kit-8 assay, EdU assay, flow cytometry assay, wound healing assay and transwell assay, respectively. Interaction between LINC00667 and miR-200b-3p or miR-200b-3p and SLC2A3 were confirmed using a luciferase reporter assay.

RESULTS

In this work, we found that LINC00667 expression was up-regulated in EC cell lines, and LINC00667 knockdown inhibited cell proliferation, migration, and invasion in EC cells. In addition, it showed that LINC00667 functioned as competitive endogenous RNA for miR-200b-3p by the DIANA-LncBase database. Moreover, we used targetscan online software to predict SLC2A3 as a target gene of miR-200b-3p. Subsequently, rescue experiments confirmed that knocking out SLC2A3 could reverse the inhibitory effect of miR-200b-3p on EC cells transfected with sh-LINC00667.

CONCLUSION

Herein, we revealed the novel mechanism of LINC00667 on regulating metastasis-related gene by sponge regulatory axis during EC metastasis. Our results demonstrated that LINC00667 plays a critical role in metastatic EC by mediating sponge regulatory axis miR-200b-3p/SLC2A3. To explore function of LINC00667/miR-200b-3p/SLC2A3 axis may provide an informative biomarker of malignancy and a highly selective anti-EC therapeutic target.

Association of Serum Pepsinogens With Esophageal Squamous Cell Carcinoma Risk: A Systematic Review and Meta-Analysis

Background

Serum pepsinogens are serological biomarkers of gastric atrophy, and the latter is a risk factor for esophageal squamous cell carcinoma (ESCC). However, the association of serum pepsinogens with ESCC risk remains unclear. This systematic review and meta-analysis aimed to assess the relationship between serum pepsinogen I (PGI) and pepsinogen I: pepsinogen II ratio (PGR) and ESCC risk.

Methods

PubMed, Embase, and Web of Science were searched for articles on the effect of serum PGI and PGR on ESCC risk, published up to the end of February 2022. Meta-analysis with a random-effect model was used to calculate pooled odds ratios (ORs) and 95% confidence intervals (CIs).

Results

Five case–control studies and three prospective studies were included. In comparison with the high categories, the low categories of serum PGI (OR: 1.92, 95% CI: 1.45–2.56) and PGR (OR: 1.70, 95% CI: 1.01–2.85) were associated with an increased risk of ESCC, although a substantial heterogeneity was observed in serum PGR (I² = 60.2%, P = 0.028) rather than in serum PGI (I² = 46.4%, P = 0.070). In stratified analysis by study quality, the significant risk effect on ESCC was remained for PGI (OR: 2.05, 95% CI: 1.48–2.84) and PGR (OR: 2.07, 95% CI: 1.17–3.75) when only the studies with high quality were pooled.

Conclusions

Based on the available studies, although limited in number, this systematic review along with meta-analysis suggests that low serum PGI and low PGR may be related to an increased risk of ESCC. This present study provides evidence for using serum pepsinogen biomarkers in predicting ESCC. More delicate well-designed cohort studies with high study quality are needed, and dose–response analysis should be performed.

Comparative effectiveness and stage-shift effect of endoscopic exam among newly diagnosed oral cancer patients with different stages in Taiwan

BACKGROUND

Patients with oral cancer are at higher risk of developing second primary esophageal cancer (SPEC) and the consensus for screening strategies remains unclear. This study aimed to examine comparative effectiveness and the stage-shift effect of endoscopic exam among patients with oral cancer.

METHOD

A population-based longitudinal retrospective observational matched case and control cohort study with at least 5 years follow-up was conducted. We identified 45 457 newly diagnosed patients with oral cancer, 2004-2013, and the eligible patient with oral cancer was 39 401. Propensity score matching was used to match comparable groups, and the two groups (screening vs. nonscreening) was 5941, individually. The study primary endpoints were to compare detection of incident SPEC and the stage-shift effect of endoscopic screening between screened and nonscreened incident oral cancer patients. Cox proportional hazard and competing risk models were analyzed. Statistical analyses were conducted in 2020-2021.

RESULT

Detection of incident SPEC in the screened group was significantly higher than in the nonscreened group (hazard ratio: 2.92, 95% confidence interval [CI]: 2.29-3.72). The stage-shift effect from endoscopic screening was found overall in patients with oral cancer (odds ratio [OR]: 0.39, 95%CI: 0.21-0.70), in particular in advanced-stage patients (OR: 0.25, 95%CI: 0.11-0.61), but not in early-stage patients (OR: 0.60, 95%CI: 0.26-1.40).

CONCLUSION

This study confirmed that endoscopic screening achieved early detection of SPEC among patients with oral cancer. To improve the screening stage-shift effect, patients with oral cancer are encouraged to undergo routine endoscopic screening.

Circular RNA circ_0006948 Promotes Esophageal Squamous Cell Carcinoma Progression by Regulating microRNA-3612/LASP1 Axis

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) is the most prevalent malignancy worldwide. Circular RNAs (circRNAs) circ_0006948 is reported to be upregulated in ESCC cells.

AIMS

This study is designed to explore the role and mechanism of circ_0006948 in ESCC progression.

METHODS

Circ_0006948, linear FNDC3B, microRNA-3612 (miR-3612), and LIM and SH3 protein 1 (LASP1) levels were detected by real-time quantitative polymerase chain reaction (RT-qPCR). Cell viability, colony number, migration, invasion, and apoptosis were examined by Cell Counting Kit-8 (CCK-8), colony formation, transwell, and flow cytometry assays, severally. Glucose consumption, lactate production, and ATP level were measured by the corresponding kits. Protein levels of hexokinase 2 (HK2) and lactate dehydrogenase A (LDHA), and LASP1 were assessed by western blot assay. The cytoplasmic localization of circ_0006948 was identified by the subcellular fractionation assay. The binding relationship between miR-3612 and circ_0006948 or LASP1 was predicted by starBase or TargetScan and then verified by a dual-luciferase reporter assay. The biological role of circ_0006948 on ESCC tumor growth was examined by the xenograft tumor model in vivo.

RESULTS

Circ_0006948 and LASP1 were increased, and miR-3612 was decreased in ESCC tissues and cells. Furthermore, circ_0006948 knockdown could suppress cell viability, colony number, migration, invasion, glycolysis, and boost apoptosis in ESCC cells. Mechanically, circ_0006948 could act as a sponge of miR-3612 to regulate LASP1 expression. In addition, circ_0006948 silencing inhibited ESCC tumor growth in vivo.

CONCLUSION

Circ_0006948 boosted ESCC progression partly by regulating the miR-3612/LASP1 axis, providing an underlying therapeutic target for the ESCC treatment.

E2F1-activated NRSN2 promotes esophageal squamous cell carcinoma progression through AKT/mTOR pathway

BACKGROUND

Neurensin‑2 (NRSN2) has been reported to act as an oncogene in several types of human cancer. However, the molecular mechanism of NRSN2 in esophageal squamous cell carcinoma (ESCC) remains to be elucidated.

METHODS

The mRNA expression levels of NRSN2 in ESCC tissues and cell lines were evaluated by quantitative real-time PCR (qRT-PCR). The protein expression levels of NRSN2 in ESCC tissues were measured by Immunohistochemical (IHC) method. Luciferase reporter and chromatin immunoprecipitation assays were conducted to confirm the upstream transcription factor of NRSN2. Loss- and gain-function assays were conducted to evaluate the effects of NRSN2 on ESCC cells proliferation, migration, and invasion. The function of NRSN2 was validated in vivo using tumor xenografts. The relationship between NRSN2 and AKT/mTOR pathway were confirmed by western blot assay.

RESULTS

The expression level of NRSN2 was increased in ESCC tissues and cell lines. High expression level of NRSN2 was correlated with depth of invasion, lymph node metastasis, TNM stage, and poor prognosis of ESCC patients. NRSN2 was transcribed by E2F1. Knockdown of NRSN2 significantly inhibited ESCC cells proliferation, migration, and invasion, whereas NRSN2 overexpression showed reverse phenotypes. Overexpression of NRSN2 also enhanced ESCC tumorigenicity in vivo. Furthermore, the E2F1/NRSN2 axis promoted proliferation, migration, and invasion of ESCC cells by activating the AKT/mTOR pathway.

CONCLUSION

NRSN2 is a direct transcriptional target of E2F1 to promote tumor progression in ESCC. NRSN2 may be a diagnostic biomarker or treatment target for ESCC.

Designing optimal allocations for cancer screening using queuing network models

Cancer is one of the leading causes of death, but mortality can be reduced by detecting tumors earlier so that treatment is initiated at a less aggressive stage. The tradeoff between costs associated with screening and its benefit makes the decision of whom to screen and when a challenge. To enable comparisons across screening strategies for any cancer type, we demonstrate a mathematical modeling platform based on the theory of queuing networks designed for quantifying the benefits of screening strategies. Our methodology can be used to design optimal screening protocols and to estimate their benefits for specific patient populations. Our method is amenable to exact analysis, thus circumventing the need for simulations, and is capable of exactly quantifying outcomes given variability in the age of diagnosis, rate of progression, and screening sensitivity and intervention outcomes. We demonstrate the power of this methodology by applying it to data from the Surveillance, Epidemiology and End Results (SEER) program. Our approach estimates the benefits that various novel screening programs would confer to different patient populations, thus enabling us to formulate an optimal screening allocation and quantify its potential effects for any cancer type and intervention.

We describe a mathematical modeling methodology that offers quantitative insights into the potential benefits of screening and other interventions on cancer mortality. Our queuing-theoretic approach represents a potentially useful alternative to more traditional modeling approaches, in that it can provide more detailed results and entirely circumvents the need for simulations. Our methodology can be widely applied to estimate costs and benefits of screening strategies. By providing a detailed example of our method applied to epidemiological data, we hope to encourage greater uptake of this methodology in the community.

High-throughput membrane-anchored proteome screening reveals PIEZO1 as a promising antibody-drug target for human esophageal squamous cell carcinoma

Background

Esophageal carcinoma is one of the most fatal cancers worldwide. In China, over 90% of esophageal cancer patients are diagnosed with esophageal squamous cell carcinoma (ESCC). Currently, the survival and prognosis of ESCC patients are not satisfying because of insufficient early screening and lack of efficacious medication. Accumulating studies have suggested that antibody‐drug conjugates (ADC) represent a promising antitumor strategy.

Method

Here, we carried out a specific membrane proteome screening with ESCC patients' samples using a high‐throughput antibody microarray to uncover potential targets for ADC development. Candidates were validated with expression and cytotoxicity evaluation both in vitro and in vivo.

Results

Our data have shown that the Piezo‐Type Mechanosensitive Ion Channel Component 1 (PIEZO1) is particularly overexpressed in human ESCC tumors and can be efficiently internalized when bound with its monoclonal antibody. Furthermore, the PIEZO1 antibody combined with monomethyl auristatin E (MMAE) can specifically kill PIEZO1 high‐expressed ESCC tumor cells by inducing cell cycle arrest and apoptosis. More importantly, the Anti‐PIEZO1‐MMAE can significantly suppress tumor progression in ESCC xenograft tumor models without any obvious side effects.

Conclusion

Taken together, our work demonstrates that PIEZO1 is a promising target to develop ADCs for human ESCC treatment, providing a new strategy for ESCC patients' personalized therapy.

RNA Sequencing of Tumor-Educated Platelets Reveals a Three-Gene Diagnostic Signature in Esophageal Squamous Cell Carcinoma

There is no cost-effective, accurate, and non-invasive method for the detection of esophageal squamous cell carcinoma (ESCC) in clinical practice. We aimed to investigate the diagnostic potential of tumor-educated platelets in ESCC. In this study, seventy-one ESCC patients and eighty healthy individuals were enrolled and divided into a training cohort (23 patients and 27 healthy individuals) and a validation cohort (48 patients and 53 healthy individuals). Next-generation RNA sequencing was performed on platelets isolated from peripheral blood of all participants, and a support vector machine/leave-one-out cross validation (SVM/LOOCV) approach was used for binary classification. A diagnostic signature composed of ARID1A, GTF2H2, and PRKRIR discriminated ESCC patients from healthy individuals with 91.3% sensitivity and 85.2% specificity in the training cohort and 87.5% sensitivity and 81.1% specificity in the validation cohort. The AUC was 0.924 (95% CI, 0.845–0.956) and 0.893 (95% CI, 0.821–0.966), respectively, in the training cohort and validation cohort. This 3-gene platelet RNA signature could effectively discriminate ESCC from healthy control. Our data highlighted the potential of tumor-educated platelets for the noninvasive diagnosis of ESCC. Moreover, we found that keratin and collagen protein families and ECM-related pathways might be involved in tumor progression and metastasis of ESCC, which might provide insights to understand ESCC pathobiology and advance novel therapeutics.

Genome-wide gain-of-function screening identifies EZH2 mediating resistance to PI3Kα inhibitors in oesophageal squamous cell carcinoma

Phosphoinositide-3 kinase alpha (PI3Kα) has been confirmed to be a potential therapeutic target for esophageal squamous cell carcinoma (ESCC), while the potency of PI3Kα inhibitors is often attenuated by concurrent oncogenic signalling pathways. We performed genome-wide gain-of-function screening with a CRISPR-SAM library and identified enhancer of zeste homolog 2 (EZH2) rendering ESCC cells resistant to the PI3Kα inhibitor CYH33. Enhanced expression of EZH2 frequently occurs in ESCC and is related to poor prognosis. Overexpression of full-length EZH2 but not methyltransferase-deficient EZH2 conferred resistance to CYH33, while downregulating EZH2 expression restored sensitivity. EZH2 expression was negatively related to the activity of CYH33 against the proliferation of ESCC cell lines and patient-derived cells. Transcriptomic analysis revealed that EZH2 abrogated CYH33-mediated cell cycle regulation. EZH2 epigenetically suppressed the transcription of CDKN1A, promoting RB phosphorylation and cell cycle progression. Concurrently targeting EZH2 significantly potentiated CYH33 to inhibit the growth of ESCC cells and patient-derived xenografts accompanied by enhanced cell cycle arrest. Taken together, our study demonstrated that an EZH2-p21-RB axis remodeled cell cycle regulation and rendered resistance to PI3Kα inhibitors in ESCC. Simultaneously targeting PI3Kα and EZH2 may provide an effective strategy for ESCC therapy with high expression of EZH2.

Upregulation of Centromere Proteins as Potential Biomarkers for Esophageal Squamous Cell Carcinoma Diagnosis and Prognosis

Esophageal squamous cell carcinoma (ESCC) has a high incidence and low survival rate, necessitating the identification of novel specific biomarkers. Centromere-associated proteins (CENPs) have been reported to be biomarkers for many cancers, but their roles in ESCC have seldom been investigated. Here, the potential clinical roles of CENPs in ESCC patients were demonstrated by a systematic bioinformatics analysis. Most CENP-encoding genes were differentially expressed between tumor and normal tissues. CENPA, CENPE, CENPF, CENPI, CENPM, CENPN, CENPQ, and CENPR were upregulated universally in the three datasets. Survival analysis demonstrated that high expression of CENPE and CENPQ was positively correlated with the outcomes of ESCC patients. The CENPE-based forecast model was more accurate than the tumor-node-metastasis (TNM) staging-based model, which was classified as stage I/II vs. III/IV. More importantly, the forecast model based on the commonly upregulated CENPs exhibited a much higher area under the curve (AUC) value (0.855) than the currently known TTL, ZNF750, AC016205.1, and BOLA3 biomarkers. The nomogram model integrating the CENPs, TNM stage, and sex was highly accurate in the prognosis of ESCC patients ( $\text{AUC}=0.906$ ). Besides, gene set enrichment analysis (GSEA) demonstrated that CENPE expression is significantly correlated with cell cycle, G2/M checkpoint, mitotic spindle, p53, etc. Finally, in validation experiments, we also found that CENPE and CENPQ were significantly overexpressed in esophageal cancer cells. Taken together, these results clearly suggest that CENPs are clinically promising diagnostic and prognostic biomarkers for ESCC patients.

Extracellular vesicle IL-32 promotes the M2 macrophage polarization and metastasis of esophageal squamous cell carcinoma via FAK/STAT3 pathway

Background

Metastasis is the leading cause of mortality in human cancers, including esophageal squamous cell carcinoma (ESCC). As a pro-inflammatory cytokine, IL-32 was reported to be a poor prognostic factor in many cancers. However, the role of IL-32 in ESCC metastasis remains unknown.

Methods

ESCC cells with ectopic expression or knockdown of IL-32 were established and their effects on cell motility were detected. Ultracentrifugation, Transmission electron microscopy and Western blot were used to verify the existence of extracellular vesicle IL-32 (EV-IL-32). Coculture assay, immunofluorescence, flow cytometry, and in vivo lung metastasis model were performed to identify how EV-IL-32 regulated the crosstalk between ESCC cells and macrophages.

Results

Here, we found that IL-32 was overexpressed and positively correlated to lymph node metastasis of ESCC. IL-32 was significantly higher in the tumor nest compared with the non-cancerous tissue. We found that IL-32β was the main isoform and loaded in EV derived from ESCC cells. The shuttling of EV-IL-32 derived from ESCC cells into macrophages could promote the polarization of M2 macrophages via FAK-STAT3 pathway. IL-32 overexpression facilitated lung metastasis and was positively correlated with the proportion of M2 macrophages in tumor microenvironment.

Conclusions

Taken together, our results indicated that EV-IL-32 derived from ESCC cell line could be internalized by macrophages and lead to M2 macrophage polarization via FAK-STAT3 pathway, thus promoting the metastasis of ESCC. These findings indicated that IL-32 could serve as a potential therapeutic target in patients with ESCC.

Supplementary information

The online version contains supplementary material available at 10.1186/s13046-022-02348-8.

Hot Tea Consumption and Esophageal Cancer Risk: A Meta-Analysis of Observational Studies

Objective

Many laboratory studies have shown that tea consumption protected against the development of esophageal cancer (EC). However, in epidemiological studies, inconsistent or even contradictory results were frequently observed, especially when drinking tea at higher temperatures.

Methods

We conducted a meta-analysis based on published observational studies to explore whether hot tea consumption was a risk factor of EC. Relevant studies were searched in PubMed, Embase, and Web of science up to October 13, 2021, and we also manually retrieved the literature in the included studies and recent reviews.

Results

A total of 23 eligible reports were identified, including 5,050 cases and 10,609 controls, and a meta-analysis with Comprehensive Meta-Analysis (CMA) software (version 2.0) was conducted. A statistically significant increased EC risk was observed when drinking tea at higher temperature (odds ratios (ORs) = 1.79, 95% CI: 1.48–2.15, p = 0.00). Except for esophageal adenocarcinoma (EAC), this increased risk was also found in the majority of subgroups, which are the European and Australian populations.

Conclusions

This meta-analysis showed that people who drank hot tea had a significantly increased risk of Esophageal squamous cell carcinoma (ESCC), but no significant association for EAC.