Circulating miRNAs in patients with Barrett's esophagus, high-grade dysplasia and esophageal adenocarcinoma

Expanding beyond endoscopy: A review of non-invasive modalities in Barrett’s esophagus screening and surveillance

Barrett’s esophagus (BE) is a condition that results from replacement of the damaged normal squamous esophageal mucosa to intestinal columnar mucosa and is the most significant predisposing factor for development of esophageal adenocarcinoma. Current guidelines recommend endoscopic evaluation for screening and surveillance based on various risk factors which has limitations such as invasiveness, availability of a trained specialist, patient logistics and cost. Trans-nasal endoscopy is a less invasive modality but still has similar limitations such as limited availability of trained specialist and costs. Non-endoscopic modalities, in comparison, require minimal intervention, can be done in an office visit and has the potential to be a more ideal choice for mass public screening and surveillance, particularly in patents at low risk for BE. These include newer generations of esophageal capsule endoscopy which provides direct visualization of BE, and tethered capsule endomicroscopy which can obtain high-resolution images of the esophagus. Various cell collection devices coupled with biomarkers have been used for BE screening. Cytosponge, in combination with TFF3, as well as EsophaCap and EsoCheck have shown promising results in various studies when used with various biomarkers. Other modalities including circulatory microRNAs and volatile organic compounds that have demonstrated favorable outcomes. Use of these cell collection methods for BE surveillance is a potential area of future research.

SOX17-mediated MALAT1-miR-199a-HIF1α axis confers sensitivity in esophageal squamous cell carcinoma cells to radiotherapy

Radiotherapy is a main modality of esophageal squamous cell carcinoma (ESCC) treatment, while radioresistance largely limits the effect of this therapy. Evidence exists reporting that SOX17 may sensitize ESCC cells to irradiation, but the downstream mechanism remains poorly understood. Therefore, we attempt to explore the molecular basis of SOX17 effect on radioresistance in ESCC. The SOX17 expression was measured in ESCC tissues and cells, followed by evaluation of its relationship with patient survival. The fractionated irradiation-induced irradiation-resistant cell line KYSE150R was subjected to gain- and loss-of function studies to explore the effect of SOX17 and downstream effectors MALAT1, miR-199a, and HIF1α on the malignant phenotypes of ESCC. The interaction among these factors was explained using ChIP, dual luciferase reporter, RNA pull-down and RIP assays. Further, the in vivo effect of SOX17 on ESCC irradiation tolerance was assessed in nude mice. SOX17 was underexpressed in ESCC tissues and cells, which was negatively correlated with the prognosis of patients with ESCC. Besides, SOX17 inhibited irradiation tolerance of ESCC cells by suppressing MALAT1 transcription. Notably, MALAT1 acted as miR-199a sponge and thereby enhanced HIF1α expression. Moreover, SOX17 reduced the irradiation tolerance of ESCC cells by reducing HIF1α expression via the MALAT1-miR-199a axis, and attenuated tumor formation in nude mice. Our results indicate that SOX17 can impede the radioresistance of ESCC cells through the MALAT1-miR-199a-HIF1α axis, in support of further research for ESCC radiotherapy.

Comprehensive RNA dataset of tissue and plasma from patients with esophageal cancer or precursor lesions

In the past decades, the incidence of esophageal adenocarcinoma has increased dramatically in Western populations. Better understanding of disease etiology along with the identification of novel prognostic and predictive biomarkers are urgently needed to improve the dismal survival probabilities. Here, we performed comprehensive RNA (coding and non-coding) profiling in various samples from 17 patients diagnosed with esophageal adenocarcinoma, high-grade dysplastic or non-dysplastic Barrett’s esophagus. Per patient, a blood plasma sample, and a healthy and disease esophageal tissue sample were included. In total, this comprehensive dataset consists of 102 sequenced libraries from 51 samples. Based on this data, 119 expression profiles are available for three biotypes, including miRNA (51), mRNA (51) and circRNA (17). This unique resource allows for discovery of novel biomarkers and disease mechanisms, comparison of tissue and liquid biopsy profiles, integration of coding and non-coding RNA patterns, and can serve as a validation dataset in other RNA landscaping studies. Moreover, structural RNA differences can be identified in this dataset, including protein coding mutations, fusion genes, and circular RNAs.

Barrett's esophagus: The pathomorphological and molecular genetic keystones of neoplastic progression

Barrett's esophagus is a widespread chronically progressing disease of heterogeneous nature. A life threatening complication of this condition is neoplastic transformation, which is often overlooked due to lack of standardized approaches in diagnosis, preventative measures and treatment. In this essay, we aim to stratify existing data to show specific associations between neoplastic transformation and the underlying processes which predate cancerous transition. We discuss pathomorphological, genetic, epigenetic, molecular and immunohistochemical methods related to neoplasia detection on the basis of Barrett's esophagus. Our review sheds light on pathways of such neoplastic progression in the distal esophagus, providing valuable insight into progression assessment, preventative targets and treatment modalities. Our results suggest that molecular, genetic and epigenetic alterations in the esophagus arise earlier than cancerous transformation, meaning the discussed targets can help form preventative strategies in at-risk patient groups.

Circulating MicroRNAs in Relation to Esophageal Adenocarcinoma Diagnosis and Survival

BACKGROUND AND AIMS

Tissue miRNA can discriminate between esophageal adenocarcinoma (EA) and normal epithelium. However, no studies have examined a comprehensive panel of circulating miRNAs in relation to EA diagnosis and survival.

METHODS

We used all 62 EA cases from the US Multi-Center case-control study with available serum matched 1:1 to controls. Cases were followed for vital status. MiRNAs (n = 2064) were assessed using the HTG EdgeSeq miRNA Whole Transcriptome Assay. Differential expression analysis of miRNAs in relation to case-control status was conducted. In cases, Cox regression models were fit to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause mortality. P values were adjusted using the Benjamini-Hochberg (BH) procedure for false discovery rate control. Predictive performance was assessed using cross-validation.

RESULTS

Sixty-eight distinct miRNAs were significantly upregulated between cases and controls (e.g., miR-1255b-2-3p fold change = 1.74, BH-adjusted P = 0.01). Assessing the predictive performance of these significantly upregulated miRNAs yielded 60% sensitivity, 65% specificity, and 0.62 AUC. miR-4253 and miR-1238-5p were associated with risk of mortality after EA diagnosis (HR = 4.85, 95% CI: 2.30-10.23, BH-adjusted P = 0.04 and HR = 3.81, 95% CI: 2.02-7.19, BH-adjusted P = 0.04, respectively).

CONCLUSIONS

While they require replication, these findings suggest that circulating miRNAs may be associated with EA diagnosis and survival.

Screening for Barrett's Oesophagus: Are We Ready for it?

Purpose of review

The targeted approach adopted for Barrett’s oesophagus (BO) screening is sub-optimal considering the large proportion of BO cases that are currently missed. We reviewed the literature highlighting recent technological advancements in efforts to counteract this challenge. We also provided insights into strategies that can improve the outcomes from current BO screening practises.

Recent findings

The standard method for BO detection, endoscopy, is invasive and expensive and therefore inappropriate for mass screening. On the other hand, endoscopy is more cost-effective for screening a high-risk population. A consensus has however not been reached on who should be screened. Risk prediction algorithms have been tested as an enrichment pre-screening tool reporting modest AUC’s but require more prospective evaluation studies. Less invasive endoscopy methods like trans-nasal endoscopy, oesophageal capsule endsocopy and non-endoscopic cell collection devices like the Cytosponge coupled with biomarker analysis have shown promise in BO detection with randomised clinical trial evidence.

Summary

A three-tier precision cancer programme whereby risk prediction algorithms and non-endoscopic minimally invasive cell collection devices are used to triage test a wider pool of individuals may improve the detection rate of current screening practises with minimal cost implications.

Extracellular miRNAs for the Management of Barrett's Esophagus and Esophageal Adenocarcinoma: A Systematic Review

Esophageal adenocarcinoma (EAC), the major histologic type of esophageal cancer (EC) in Western countries, is a disease with a poor prognosis, primarily due to usual diagnosis at an advanced stage. The prevalence of EAC has increased in recent years, both in Western countries and in Asia. Barrett's esophagus (BE) is a precursor lesion of EAC. Therefore, early detection and proper management of BE and EAC is important to improve prognosis. Here, we systematically summarize current knowledge about the potential utility of extracellular microRNAs (miRNAs), which are thought to be non-invasive biomarkers for many diseases, for these purposes. A search of the PubMed and Embase databases identified 22 papers about extracellular miRNAs that have potential utility for management of EAC. Among them, 19 were EAC-related and ten were BE-related; some of these dealt with both conditions. The articles included studies reporting diagnosis, prognosis, and treatment responses. Multiple papers report dysregulation of miR-194-5p in BE and miR-21-5p, -25-3p, and -93-5p in EAC. Although it will take time to utilize these miRNAs in clinical practice, they are likely to be useful non-invasive markers in the future.

The Diagnostic and Prognostic Value of a Liquid Biopsy for Esophageal Cancer: A Systematic Review and Meta-Analysis

Simple Summary

The “liquid biopsy” is a novel concept for detecting circulating biomarkers in the peripheral blood of patients with various cancers, including esophageal cancer. There are two main methods to identify circulating cancer related biomarkers such as morphological techniques or molecular biological techniques. There are some differences in the sensitivity and specificity for detecting circulating tumor cells (CTCs) or circulating markers between each method. Although it is still challenging to determine strong candidates for early diagnosis and predicting prognosis in patients with esophageal cancer, our meta-analysis might be a milestone for the future development of liquid biopsies in use with esophageal cancer.

Abstract

Esophageal cancer is among the most aggressive diseases, and circulating tumor cells (CTCs) have been recognized as novel biomarkers for various cancers over the past two decades, including esophageal cancer. CTCs might provide crucial clinical information for predicting cancer prognosis, monitoring therapeutic responses or recurrences, or elucidating the mechanism of metastasis. The isolation of CTCs is among the applications of a “liquid biopsy”. There are various technologies for liquid biopsies, and they are classified into two main methods: cytometric or non-cytometric techniques. Here, we review a total of 57 eligible articles to summarize various technologies for the use of a liquid biopsy in esophageal cancer and perform a meta-analysis to assess the clinical utility of liquid biopsies as a prognostic and diagnostic biomarker technique. For prognostic evaluation, the pooled hazard ratio in the cytometric assay is relatively higher than that of the non-cytometric assay. On the other hand, a combination of multiple molecules, using a non-cytometric assay, might be a favorable biomarker technique for the early diagnosis of esophageal cancer. Although determining strong evidence for a biomarker by using a liquid biopsy is still challenging, our meta-analysis might be a milestone for the future development of liquid biopsies in use with esophageal cancer.

Role of non-coding RNAs in esophageal carcinoma

In recent years, the research on the role of non-coding RNAs (ncRNAs) in tumors has received more and more attention. Although research on the role of ncRNAs in the early diagnosis, disease monitoring, treatment guidance, and prognosis prediction of esophageal carcinoma has been gradually carried out, there are still many problems that need to be addressed. In the current paper, I review the progress in the research of ncRNAs in esophageal carcinoma, with an aim to help provide new strategies for the prevention and treatment of esophageal carcinoma.

Circulating microRNA expression profiling revealed miR-92a-3p as a novel biomarker of Barrett's carcinogenesis

The main intent of secondary prevention strategies for Barrett's esophagus (BE) patients relies in the prompt identification of patients with dysplasia (or intra-epithelial neoplasia; IEN) and early-stage adenocarcinoma (Barrett's adenocarcinoma; BAc). Despite the adequate characterization of the molecular landscape characterizing Barrett's carcinogenesis, no tissue and/or circulating biomarker has been approved for clinical use. A series of 25 serum samples (12 BE, 5 HG-IEN and 8 BAc) were analyzed for comprehensive miRNA profiling and ten miRNAs were found to be significantly dysregulated. In particular seven were upregulated (i.e. miR-92a-3p, miR-151a-5p, miR-362-3p, miR-345-3p, miR-619-3p, miR-1260b, and miR-1276) and three downregulated (i.e. miR-381-3p, miR-502-3p, and miR-3615) in HG-IEN/BAc samples in comparison to non-dysplastic BE. All the identified miRNAs showed significant ROC curves in discriminating among groups with AUC values range of 0.75-0.83. Validation of the results were performed by droplet digital PCR in two out of three tested miRNAs. To understand the cellular source of circulating miR-92a-3p, we analyzed its expression in endoscopy biopsy samples by both qRT-PCR and ISH analyses. As observed in serum samples, miR-92a-3p was over-expressed in HG-IEN/BAc samples in comparison to naïve esophageal squamous mucosa and BE and was mainly localized within the epithelial cells, supporting neoplastic cells as the main source of the circulating miRNA. Our data further demonstrated that circulating miRNAs are a promising mini-invasive diagnostic tool in the secondary follow-up and management of BE patients. Larger multi-Institutional studies should validate and investigate the most adequate miRNAs profile in discriminating BE patients in specific risk classes.