Non-acid reflux: the missing link between gastric atrophy and esophageal squamous cell carcinoma?

Hybrid Minimally Invasive Esophagectomy for Carcinoma Oesophagus: Experience at Tertiary Care Centre in North Karnataka

Surgery remains the mainstay for curative treatment of carcinoma of midthoracic and lower thoracic oesophagus. In the twentieth century, open esophagectomy was the standard of care. In the twenty-first century, treatment for carcinoma oesophagus has revolutionized with incorporation of neoadjuvant treatment and application of various minimally invasive techniques for esophagectomy. At present, there is no consensus about the optimum position to perform minimally invasive esophagectomy (MIE). We share our experience of MIE with modification in the port position in this article.

Screening of tumor grade-related mRNAs and lncRNAs for Esophagus Squamous Cell Carcinoma

Background

The goal of our study was to screen tumor grade‐related lncRNAs and mRNAs to reveal the underlying molecular mechanism of esophagus squamous cell carcinoma (ESCC).

Methods

The lncRNA and mRNA sequencing data were obtained from The Cancer Genome Atlas (TCGA). Tumor grade correlation analysis of lncRNAs and mRNAs was executed, followed by the functional enrichment analysis of all tumor grade‐related mRNAs. The differentially expression mRNAs (DEmRNAs) and differentially expressed lncRNAs (DElncRNAs) were obtained. PPI network and DEmRNA‐DElncRNA interaction analysis were constructed. The functional annotation of the DEmRNAs co‐expressed with DElncRNAs was performed. The expression levels of the candidate genes were validated using qRT‐PCR.

Results

A total of 1864 tumor grade‐related mRNAs (846 positively related and 1018 negatively related) and 552 tumor grade‐related lncRNAs (331 positively related and 221 negatively related) were obtained. The top 10 significantly grade‐related mRNAs and lncRNAs included CA12, FABP4, DECR1, BAIAP2, IL1RAPL2, PPARD, LAD1, TSPAN10, LDOC1, ZNF853, RP11‐25G10.2, RP11‐557H15.3, RP11‐521D12.5, CHKB‐AS1, RP11‐219B4.3, CH17‐335B8.4, RP11‐99 J16‐A.2, CTB‐111H14.1, ADNP‐AS1, and JHDM1D‐AS1. SFN, IL1RAPL2, and RP11‐25G10.2 were overlapped from grade 1, grade 2, and grade 3. PPI network showed that top 10 proteins with higher degrees, including GNAI1, RAP2B, GNAZ, SHH, ADCY1, PRKAR2B, SH3GL1, GNA15, and ARRB1. A DElncRNAs‐nearby DEmRNAs network was constructed to obtain hub lncRNAs including ADAMTS9‐AS2, RP11‐210 M15.2, RP11‐13 K12.1, ZBED3‐AS1, and RP11‐25G10.2. Except for RP11‐25G10.2, ADAMTS9‐AS1, ZBED3‐AS1, SFN, ATP1A2, and GNA15 were consistent with our TCGA analysis.

Conclusions

Alterations of DEmRNAs and DElncRNAs may provide key insights into the molecular mechanisms of ESCC.

A Prognostic Signature Based on Immunogenomic Profiling Offers Guidance for Esophageal Squamous Cell Cancer Treatment

Our study aimed to develop an immune prognostic signature that could provide accurate guidance for the treatment of esophageal squamous cell cancer (ESCC). By implementing Single-Sample Gene Set Enrichment Analysis (ssGSEA), we established two ESCC subtypes (Immunity High and Immunity Low) in GSE53625 based on immune-genomic profiling of twenty-nine immune signature. We verified the reliability and reproducibility of this classification in the TCGA database. Immunity High could respond optimally to immunotherapy due to higher expression of immune checkpoints, including PD1, PDL1, CTLA4, and CD80. We used WGCNA analysis to explore the underlying regulatory mechanism of the Immunity High group. We further identified differentially expressed immune-related genes (CCR5, TSPAN2) in GSE53625 and constructed an independent two-gene prognostic signature we internally validated through calibration plots. We established that high-risk ESCC patients had worse overall survival (P=0.002, HR=2.03). Besides, high-risk ESCC patients had elevated levels of infiltrating follicle-helper T cells, naïve B cells, and macrophages as well as had overexpressed levels of some immune checkpoints, including B3H7, CTLA4, CD83, OX40L, and GEM. Moreover, through analyzing the Genomics of Drug Sensitivity in Cancer (GDSC) database, the high-risk group demonstrated drug resistance to some chemotherapy and targeted drugs such as paclitaxel, gefitinib, erlotinib, and lapatinib. Furthermore, we established a robust nomogram model to predict the clinical outcome in ESCC patients. Altogether, our proposed immune prognostic signature constitutes a clinically potential biomarker that will aid in evaluating ESCC outcomes and promote personalized treatment.

The Impact of Whole Grain Intake on Gastrointestinal Tumors: A Focus on Colorectal, Gastric, and Esophageal Cancers

Cereals are one of staple foods in human diet, mainly consumed as refined grains. Nonetheless, epidemiological data indicate that whole grain (WG) intake is inversely related to risk of type 2 diabetes, cardiovascular disease, and several cancer types, as well as to all-cause mortality. Particularly responsive to WG positive action is the gastrointestinal tract, daily exposed to bioactive food components. Herein, we shall provide an up-to-date overview on relationship between WG intake and prevention of gastrointestinal tumors, with a particular focus on colorectal, stomach, and esophagus cancers. Unlike refined counterparts, WG consumption is inversely associated with risk of these gastrointestinal cancers, most consistently with the risk of colorectal tumor. Some WG effects may be mediated by beneficial constituents (such as fiber and polyphenols) that are reduced/lost during milling process. Beside health-promoting action, WGs are still under-consumed in most countries; therefore, World Health Organization and other public/private stakeholders should cooperate to implement WG consumption in the whole population, in order to reach nutritionally effective intakes.

Associations Between Gastric Atrophy and Its Interaction With Poor Oral Health and the Risk for Esophageal Squamous Cell Carcinoma in a High-Risk Region of China: A Population-Based Case-Control Study

Previous findings concerning gastric atrophy as a potential risk factor for esophageal squamous cell carcinoma (ESCC) have been inconsistent. We aimed to test whether gastric atrophy and, further, its interaction with poor oral health elevated the risk of ESCC in a high-risk region of China. Our population-based case-control study in Taixing, China (2010–2014), recruited cases from local hospitals and the local cancer registry. Controls were selected randomly from the local population registry. Ultimately, 1,210 cases and 1,978 controls answered questionnaires and provided blood samples for assay of pepsinogens. Unconditional logistic regression models were used to estimate odds ratios and 95% confidence intervals. Gastric atrophy (defined as a serum level of pepsinogen I of <55 μg/L) was associated with an increased risk for ESCC (odds ratio = 1.61; 95% confidence interval: 1.33, 1.96), even after full adjustment for potential confounding factors. In addition, suggestion of an additive interaction between gastric atrophy and poor oral health was observed (relative excess risk due to interaction = 1.28, 95% confidence interval: 0.39, 2.18). We conclude that gastric atrophy appears to be a risk factor for ESCC in a high-risk region of China, and there is a suggested additive interaction with poor oral health that increases this risk even further.

Non-acid Reflux: When It Matters and Approach to Management

PURPOSE OF REVIEW

This narrative review focuses on the presentation, contributing factors, diagnosis, and treatment of non-acid reflux. We also propose algorithms for diagnosis and treatment.

RECENT FINDINGS

There is a paucity of recent data regarding non-acid reflux. The recent Porto and Lyon consensus statements do not fully address non-acid reflux or give guidance on classification. However, recent developments in the lung transplantation field, as well as older data in the general population, argue for the importance of non-acid reflux. Extrapolating from the Porto and Lyon consensus, we generally classify pathologic non-acid reflux as impedance events > 80, acid exposure time < 4%, and positive symptom correlation on a standard 24-h pH/impedance test. Other groups not meeting this criteria also deserve consideration depending on the clinical situation. Potential treatments include lifestyle modification, increased acid suppression, alginates, treatment of esophageal hypersensitivity, baclofen, buspirone, prokinetics, and anti-reflux surgery in highly selected individuals. More research is needed to clarify appropriate classification, with subsequent focus on targeted treatments.

The Evolving Landscape of Esophageal Cancer: A Four-Decade Analysis

The incidence of esophageal cancer in the United States seems to have significantly increased since the 1970s. In undertaking this study, we sought to describe changes in the incidence, histologic type, and presenting stage of esophageal cancer over the past four decades. With Institutional Review Board approval, the Surveillance, Epidemiology, and End Results database of the National Cancer Institute was queried. Regression analysis was used to analyze data, and significance was accepted with 95 per cent probability. Forty-two thousand seven hundred thirty-nine patients had squamous cell carcinoma or adenocarcinoma located in their upper, middle, and/ or lower esophagus from 1973 through 2010, reflecting a 7.5-fold annual increase from 1973 through 2010. Squamous cell carcinoma increased annually 2.5-fold ( P < 0.001) and esophageal adenocarcinoma increased annually 57-fold from 1973 through 2010 ( P < 0.001), whereas the overall population in the United States increased only 43 per cent (215,092,900 to 308,745,538) in the same period. From 1973 through 2010, there was a significant increase in the incidence of esophageal cancer in the United States. This increase was much greater than the increase in the population in the United States. The incidence of adenocarcinoma increased much more than that of squamous cell carcinoma of the esophagus from 1973 through 2010.

ALDH1A1 maintains the cancer stem-like cells properties of esophageal squamous cell carcinoma by activating the AKT signal pathway and interacting with β-catenin

Aldehyde dehydrogenase 1A1 (ALDH1A1) is a marker of cancer stem-like cells (CSCs), but knowledge about the molecular mechanism of ALDH1A1 in maintaining the properties of CSCs remains limited. ALDH1A1 immunohistochemistry was performed in esophageal squamous cell carcinoma (ESCC) tissues, Western blotting was used to detect relationship between ALDH1A1 and AKT or β-catenin. Subcutaneous transplantation of tumors and drug resistance, spherogenesis experiments were used to test the ESCC cell stemness. Co-IP and confocal were used to detected the co-localization of LADH1A1 and β-catenin. ALDH1A1 expression maintained the CSC properties of ESCC cells. It enhanced the chemo-resistance ability, clonogenicity, and spherogenesis in vitro and tumorigenicity in vivo. High ALDH1A1 expression is an adverse prognostic factor of ESCC patients. Small-molecule inhibitor NCT-501 down-regulates ALDH1A1 expression and inhibits the AKT-β-catenin signaling pathway. ALDH1A1 overexpression activates the AKT signaling pathway. ALDH1A1 interacts with β-catenin, co-localization in KYS-510 cells.

Role of photodynamic therapy in the treatment of esophageal cancer

Photodynamic therapy (PDT), a treatment of choice for cancer, induces a photochemical reaction, thereby eradicating tumor cells. This is achieved through the administration of a photosensitizer drug, which is activated with a laser after localization to the tumor mass, and is an approved curative endoscopic ablative treatment for superficial esophageal squamous cell carcinoma (ESCC) in Japan. PDT has been approved for dysplastic Barrett's esophagus and as a palliative treatment for patients with symptomatic obstructive esophageal cancer in US. However, its adverse events and complicated procedure and the development of alternative endoscopic procedures such as endoscopic submucosal dissection, radiofrequency ablation and cryotherapy, have largely limited the practice of PDT in esophageal cancer worldwide. Recently, owing to the invention of second-generation PDT using talaporfin sodium and diode laser, PDT can be performed with less phototoxicity and therefore has regained popularity in the treatment of ESCC. As a salvage treatment for patients with local failure after chemoradiotherapy (CRT), PDT has shown promising complete response with less phototoxicity and shorter sun shade period. In addition, the efficacy and safety of PDT in patients with local failure of ESCC after CRT were shown in several clinical trials. The direction of the study interest of the next-generation PDT is the safety and potential expansion of the indications for its application in the future. This review covers the PDT for the treatment of ESCC and dysplastic Barrett's esophagus, with special focus on the role of PDT in practice for esophageal cancer.

Gene Expression Profiling Reveals Distinct Molecular Subtypes of Esophageal Squamous Cell Carcinoma in Asian Populations

Esophageal squamous cell carcinoma (ESCC) is one of the most common cancers worldwide, particularly in Asian populations, and responds poorly to conventional therapy. Subclassification of ESCCs by molecular analysis is a powerful strategy in extending conventional clinicopathologic classification, improving prognosis and therapy. Here we identified two ESCC molecular subtypes in Chinese population using gene expression profiling data and further validated the molecular subtypes in two other independent Asian populations (Japanese and Vietnamese). Subtype I ESCCs were enriched in pathways including immune response, while genes overexpressed in subtype II ESCCs were mainly involved in ectoderm development, glycolysis process, and cell proliferation. Specifically, we identified potential ESCC subtype-specific diagnostic markers (FOXA1 and EYA2 for subtype I, LAMC2 and KRT14 for subtype II) and further validated them in a fourth Asian cohort. In addition, we propose a few subtype-specific therapeutic targets for ESCC, which may guide future ESCC clinical treatment when further validated.

CD44v9 is associated with epithelial-mesenchymal transition and poor outcomes in esophageal squamous cell carcinoma

CD44 serves as a marker of cancer stem cells. Alternative splicing generates the CD44v9 isoform. Cancer stem cells are associated with the epithelial-mesenchymal transition in cancers, although little is known about their role in esophageal squamous cell carcinoma. Here, we aimed to clarify the relationship between CD44v9 expression, the epithelial-mesenchymal transition, and clinicopathological features of patients with esophageal squamous cell carcinoma. CD44v9 levels were higher at the tumor invasive front compared with the center of the tumor and higher in metastatic lymph nodes compared with primary tumors. High levels of CD44v9 at the tumor invasive front were significantly associated with deeper tumor invasion and shorter overall survival and recurrence-free survival. The expression of CD44v9 was increased by treatment with transforming growth factor-β, which induced esophageal squamous cell carcinoma cells to undergo the epithelial-mesenchymal transition. Moreover, inhibition of CD44v9 expression decreased the migration and invasiveness of esophageal squamous cell carcinoma cells. These results indicate that the expression of CD44v9 at the tumor invasive front induced by stemness was strongly associated with the epithelial-mesenchymal transition and poor prognosis of patients with esophageal squamous cell carcinoma. CD44v9 may therefore serve as a novel prognostic biomarker and a potential therapeutic target for esophageal squamous cell carcinoma.

miR-18a promotes cell proliferation of esophageal squamous cell carcinoma cells by increasing cylin D1 via regulating PTEN-PI3K-AKT-mTOR signaling axis

Esophageal squamous cell carcinoma (ESCC) is one of the lethal cancers with a high incidence rate in Asia. Cyclin D1 is overexpressed and plays an important role in the carcinogenesis of ESCC; however the mechanism of the deregulation of Cyclin D1 in ESCC remains to be determined. In the study, we found that miR-18a promotes the expression Cyclin D1 by targeting PTEN in eophageal squamous cell carcinoma TE13 and Eca109 cells. Transfection of miR-18a mimetics increased cyclin D1, while transfection of miR-18a antagomir decreased D1. Moreover, miR-18a-mediated upregulation of cyclin D1 was accompanied with downregulation of PTEN, which is a direct target of miR-18a, and increase of the phosphorylation of AKT and S6K1. In addition, pharmacologic inhibition of AKT or mTOR kinases abolished the increase of cyclinD1 by miR-18a, which was accompanied with decreased phosphorylation of RbS780 and inhibition of cell proliferation. Our results demonstrated the upregulation of miR-18a promoted cell proliferation by increasing cylin D1 via regulating PTEN-PI3K-AKT-mTOR signaling axis, suggesting that small molecule inhibitors of AKT-mTOR signaling are potential agents for the treatment of ESCC patients with upregulation of miR-17-92 cluster.

Genomic characterization of esophageal squamous cell carcinoma: Insights from next-generation sequencing

Two major types of cancer occur in the esophagus: squamous cell carcinoma, which is associated with chronic smoking and alcohol consumption, and adenocarcinoma, which typically arises in gastric reflux-associated Barrett’s esophagus. Although there is increasing incidence of esophageal adenocarcinoma in Western counties, esophageal squamous cell carcinoma (ESCC) accounts for most esophageal malignancies in East Asia, including China and Japan. Technological advances allowing for massively parallel, high-throughput next-generation sequencing (NGS) of DNA have enabled comprehensive characterization of somatic mutations in large numbers of tumor samples. Recently, several studies were published in which whole exome or whole genome sequencing was performed in ESCC tumors and compared with matched normal DNA. Mutations were validated in several genes, including in TP53, CDKN2A, FAT1, NOTCH1, PIK3CA, KMT2D and NFE2L2, which had been previously implicated in ESCC. Several new recurrent alterations have also been identified in ESCC. Combining the clinicopathological characteristics of patients with information obtained from NGS studies may lead to the development of effective diagnostic and therapeutic approaches for ESCC. As this research becomes more prominent, it is important that gastroenterologist become familiar with the various NGS technologies and the results generated using these methods. In the present study, we describe recent research approaches using NGS in ESCC.

Regenerative Medicine Strategies for Esophageal Repair

Pathologies that involve the structure and/or function of the esophagus can be life-threatening. The esophagus is a complex organ comprising nonredundant tissue that does not have the ability to regenerate. Currently available interventions for esophageal pathology have limited success and are typically associated with significant morbidity. Hence, there is currently an unmet clinical need for effective methods of esophageal repair. The present article presents a review of esophageal disease along with the anatomic and functional consequences of each pathologic process, the shortcomings associated with currently available therapies, and the latest advancements in the field of regenerative medicine with respect to strategies for esophageal repair from benchtop to bedside.

Stromal fibroblasts are predictors of disease-related mortality in esophageal squamous cell carcinoma

The growth, invasiveness and metastasis of human cancers are determined not only by cancer cells, but also by their microenvironment. Activated stromal fibroblasts promote tumor progression by secreting growth factors. In the present study, we focused on interrelations between cancer and fibroblasts, the main component of tumor stroma. We retrospectively analyzed the relations of mortality to clinical, pathological, and α-smooth muscle actin (α-SMA) characteristics in 97 consecutive patients with esophageal squamous cell carcinoma (ESCC). In vitro, we used TE-11, KYSE150 and KYSE220 ESCC cell lines and isolated esophageal stromal fibroblasts, some of which were immortalized. Migration assays were conducted to assess the effects of fibroblasts on cancer-cell migration and 3-dimensional organotypic cultures. In vivo, TE-11 and KYSE220 cells plus immortalized fibroblasts were co-transplanted subcutaneously in Nod/Scid mice to assess the effects of fibroblasts on tumorigenicity. Clinicopathologically, the α-SMA expression of cancer stroma was correlated with venous invasion (p<0.01), nodal involvement (p=0.02), recurrence (p=0.01), and was a predictor of survival in patients with stage I and II ESCC (p=0.04). In vitro, the presence of fibroblasts strongly promoted the migration of TE-11, KYSE150 and KYSE220 cells. On organotypic culture, stromal invasion was observed only in the presence of immortalized fibroblasts. In vivo, tumors developed or grew in a fibroblast‑dependent manner after implantation. Our findings provide evidence that stromal fibroblasts and tumor cells interact to promote tumor progression in ESCC. In patients with earlier stage ESCC, α-SMA may be a predictor of mortality. Inhibition of paracrine systems associated with tumor fibroblasts may slow or reverse tumor progression, potentially leading to the development of new targeted therapies.

Epidemiology of esophageal cancer

Esophageal cancer (EsC) is one of the least studied and deadliest cancers worldwide because of its extremely aggressive nature and poor survival rate. It ranks sixth among all cancers in mortality. In retrospective studies of EsC, smoking, hot tea drinking, red meat consumption, poor oral health, low intake of fresh fruit and vegetables, and low socioeconomic status have been associated with a higher risk of esophageal squamous cell carcinoma. Barrett’s esophagus is clearly recognized as a risk factor for EsC, and dysplasia remains the only factor useful for identifying patients at increased risk, for the development of esophageal adenocarcinoma in clinical practice. Here, we investigated the epidemiologic patterns and causes of EsC. Using population based cancer data from the Surveillance, Epidemiology and End Results Program of the United States; we generated the most up-to-date stage distribution and 5-year relative survival by stage at diagnosis for 1998-2009. Special note should be given to the fact that esophageal cancer, mainly adenocarcinoma, is one of the very few cancers that is contributing to increasing death rates (20%) among males in the United States. To further explore the mechanism of development of EsC will hopefully decrease the incidence of EsC and improve outcomes.