Abrams, Julian A

Background Eosinophilic oesophagitis (EoE) is a food allergen-induced inflammatory disorder characterised by interleukin (IL)-13-mediated oesophageal inflammation and epithelial basal cell hyperplasia (BCH). The role of mitochondria in EoE pathogenesis remains elusive. Design Prompted by single cell transcriptomics data, we interrogated the role of mitochondria in EoE pathobiology using patient biopsies, EoE-mouse models and oesophageal epithelial cells grown in monolayer and three-dimensional (3D) organoid cultures treated with EoE-relevant cytokines. 3D organoids and EoE-bearing mice were treated with omeprazole—a proton-pump inhibitor used as first-line EoE therapy. We performed CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) interference in mouse organoids to identify the key mitochondrial regulatory genes whose depletion may lead to BCH. We analysed mitochondrial membrane potential, mass and superoxide production by flow cytometry, cellular oxygen consumption by respirometry, mitochondrial structures and perturbation of cellular energy homeostasis by immunoblotting. Results Mitochondrial dysfunction appeared to be a hallmark of EoE-related BCH where mitochondrial structural damage was associated with impaired oxidative respiratory capacity, elevation of mitochondrial superoxide and decreased adenosine triphosphate (ATP) production, as corroborated by activation of the adenosine monophosphate (AMP) -activated protein kinase and suppression of mammalian target-of-rapamycin signalling. Depletion of PGC1A, the master regulator of mitochondria biogenesis, recapitulated EoE-related BCH, suggesting that mitochondrial dysfunction drives BCH. Further, omeprazole alleviated mitochondrial damage and dysfunction in EoE-related BCH modelled in mice and patient-derived organoids. Conclusion Mitochondrial dysfunction is tightly linked to perturbation of redox homeostasis in EoE-related BCH, which is promoted by IL-13 and reversible with omeprazole treatment.

INTRODUCTION: Reflux bile acids are believed to promote esophageal adenocarcinoma (EAC), but the role of systemic bile acids is unknown. This study aimed to assess associations between systemic bile acids and stages of Barrett's esophagus (BE) progression. METHODS: Subjects with and without BE were enrolled in this multicenter cross-sectional study. Targeted serum bile acid profiling was performed, and a subset of subjects completed a validated food frequency questionnaire. RNA sequencing was performed on BE or gastric cardia tissue to assess bile acid associations with gene expression. RESULTS: A total of 141 subjects were enrolled with serum bile acids profiled (49 non-BE; 92 BE: 44 no dysplasia, 25 indefinite/low grade dysplasia, 23 high-grade dysplasia/EAC). Lower Healthy Eating Index score, older age, higher body mass index, and no proton pump inhibitor use were associated with increased levels of multiple bile acids. Global bile acid pools were distinct between non-BE and stages of BE neoplasia ( P = 0.004). Increasing cholic acid was associated with high-grade dysplasia/EAC compared with non-BE, even after adjusting for EAC risk factors (adjusted odds ratio 2.03, 95% confidence interval 1.11–3.71) as was the combination of unconjugated primary bile acids (adjusted odds ratio 1.81, 95% confidence interval 1.04–3.13). High cholic acid levels were associated with tissue gene expression changes including increased DNA replication and reduced lymphocyte differentiation genes. DISCUSSION: Alterations in serum bile acids are independently associated with advanced neoplasia in BE and may contribute to neoplastic progression. Future studies should explore associated gut microbiome changes, proneoplastic effects of bile acids, and whether these bile acids, particularly cholic acid, represent potential biomarkers or viable therapeutic targets for advanced neoplasia in BE.

INTRODUCTION: Early neoplastic progression of Barrett's esophagus (BE) is often treated with endoscopic therapy. Although effective, some patients are refractory to therapy or recur after apparent eradication of the BE. The goal of this study was to determine whether genomic alterations within the treated BE may be associated with persistent or recurrent disease. METHODS: We performed DNA sequencing on pre-treatment esophageal samples from 45 patients who were successfully treated by endoscopic therapy and did not recur as well as pre-treatment and post-treatment samples from 40 patients who had persistent neoplasia and 21 patients who had recurrent neoplasia. The genomic alterations were compared between groups. RESULTS: The genomic landscape was similar between all groups. Patients with persistent disease were more likely to have pre-treatment alterations involving the receptor tyrosine kinase pathway ( P = 0.01), amplifications of oncogenes ( P = 0.01), and deletions of tumor suppressor genes ( P = 0.02). These associations were no longer significant after adjusting for patient age and BE length. More than half of patients with persistent (52.5%) or recurrent (57.2%) disease showed pre-treatment and post-treatment samples that shared at least 50% of their driver mutations. DISCUSSION: Pre-treatment samples were genomically similar between those who responded to endoscopic therapy and those who had persistent or recurrent disease, suggesting there is not a strong genomic component to treatment response. Although it was expected to find shared driver mutations in pre-treatment and post-treatment samples in patients with persistent disease, the finding that an equal number of patients with recurrent disease also showed this relation suggests that many recurrences represent undetected minimal residual disease.

INTRODUCTION: A substantial proportion of patients with esophageal adenocarcinoma (EAC) do not report gastroesophageal reflux disease (GERD) symptoms. This study aimed to compare the risk factor profiles and cancer stage at presentation of patients with EAC with and without prior GERD. METHODS: In this retrospective cross-sectional study, patients with EAC were divided into 2 cohorts: (i) EAC with prior GERD: patients who reported typical GERD symptoms (heartburn or regurgitation) ≥1 year before cancer diagnosis and (ii) EAC without prior GERD: patients who did not report prior GERD symptoms or reported symptoms within 1 year of their cancer diagnosis. Baseline demographics, risk factors, and cancer stage at presentation were compared between the 2 cohorts. In addition, the distribution of patients based on numbers of BE/EAC–associated risk factors (1, 2, 3, 4, and 5 or more) was examined in the symptomatic and asymptomatic cohorts. RESULTS: Over 13 years, 388 patients with EAC with prior GERD and 245 patients with EAC without prior GERD were recruited. Both groups had similar baseline demographics and risk factors, but patients with EAC with prior GERD were more likely to have a history of BE. Asymptomatic patients had more advanced disease. Patients with 3 or more BE/EAC–related risk factors formed the largest proportion of patients in both the symptomatic and asymptomatic cohorts. DISCUSSION: Patients with EAC with and without prior GERD symptoms are phenotypically similar, suggesting that BE screening efforts to prevent or detect early EAC should not be restricted to just those with GERD.

INTRODUCTION: An estimated 15%–29% of patients report new gastrointestinal (GI) symptoms after coronavirus-19 disease (COVID-19) while 4%–31% report new depressive symptoms. These symptoms may be secondary to gut microbiome tryptophan metabolism and 5-hydroxytryptamine (5-HT)-based signaling. METHODS: This study used specimens from 2 patient cohorts: (i) fecal samples from patients with acute COVID-19 who participated in a randomized controlled trial testing prebiotic fiber and (ii) blood samples from patients with acute COVID-19. Six months after recovering from COVID-19, both cohorts answered questions related to GI symptoms and anxiety or depression. Microbiome composition and function, focusing on tryptophan metabolism-associated pathways, and plasma 5-HT were assessed. RESULTS: In the first cohort (n = 13), gut microbiome L-tryptophan biosynthesis during acute COVID-19 was decreased among those who developed more severe GI symptoms (2.0-fold lower log activity comparing those with the most severe GI symptoms vs those with no symptoms, P = 0.06). All tryptophan pathways showed decreased activity among those with more GI symptoms. The same pathways were also decreased in those with the most severe mental health symptoms after COVID-19. In an untargeted analysis, 5 additional metabolic pathways significantly differed based on subsequent development of GI symptoms. In the second cohort (n = 39), plasma 5-HT concentration at the time of COVID-19 was increased 5.1-fold in those with GI symptoms alone compared with those with mental health symptoms alone ( P = 0.02). DISCUSSION: Acute gut microbiome-mediated reduction in 5-HT signaling may contribute to long-term GI and mental health symptoms after COVID-19. Future studies should explore modification of 5-HT signaling to reduce post-COVID symptoms.

INTRODUCTION: Ablation of Barrett's esophagus (BE) is the preferred approach for the treatment of neoplasia without visible lesions. Limited data on cryoballoon ablation (CBA) suggest its potential clinical utility. We evaluated the safety and efficacy of CBA in a multicenter study of patients with neoplastic BE. METHODS: In a prospective clinical trial, 11 academic and community centers recruited consecutive patients with BE of 1–6 cm length and low-grade dysplasia, high-grade dysplasia (HGD), or intramucosal adenocarcinoma (ImCA) confirmed by central pathology. Patients with symptomatic pre-existing strictures or visible BE lesions had dilation or endoscopic mucosal resection (EMR), respectively, before enrollment. A nitrous oxide cryoballoon focal ablation system was used to treat all visible columnar mucosa in up to 5 sessions. Study end points included complete eradication of all dysplasia (CE-D) and intestinal metaplasia (CE-IM) at 1 year. RESULTS: One hundred twenty patients with BE with ImCA (20%), HGD (56%), or low-grade dysplasia (23%) were enrolled. In the intention-to-treat analysis, the CE-D and CE-IM rates were 76% and 72%, respectively. In the per-protocol analysis (94 patients), the CE-D and CE-IM rates were 97% and 91%, respectively. Postablation pain was mild and short lived. Fifteen subjects (12.5%) developed strictures requiring dilation. One patient (0.8%) with HGD progressed to ImCA, which was successfully treated with EMR. Another patient (0.8%) developed gastrointestinal bleeding associated with clopidogrel use. One patient (0.8%) had buried BE with HGD in 1 biopsy, not confirmed by subsequent EMR. DISCUSSION: In patients with neoplastic BE, CBA was safe and effective. Head-to-head comparisons between CBA and other ablation modalities are warranted (clinicaltrials.gov registration NCT02514525).

83 Background: Although surgery is traditionally the standard of care for esophageal cancer, esophagectomy carries significant morbidity and mortality. Alternative endoscopic therapies are needed for patients who are not candidates for conventional treatment. The objective of this study was to assess the safety, efficacy, and tolerability of spray cryotherapy of esophageal cancer. Methods: This study includes patients enrolled retrospectively and prospectively in an open-label registry and patients in a retrospective cohort from twelve academic and community practices. Endoscopic spray cryotherapy was performed until local tumor eradication was confirmed by biopsy or until treatment was halted due to progression of disease, patient withdrawal or co-morbidities. Results: One-hundred and eight patients (median age 75.5, 79.6% male, 93.5% adenocarcinoma, mean length 5.2 cm) underwent 442 treatments (mean 4.2 per patient). Tumor stages included 40 with T1a, 27 with T1b, 10 with unspecified T1, 15 with T2, and 16 with no T stage reported. One-hundred and six patients completed treatment with complete response of intraluminal disease in 54.7%, including complete response in 74.4% for T1a, 50% for T1b, 65.3% for all T1, 6.7% for T2, and 50% for those with no T stage reported. Mean follow-up was 17.3 months. There were no deaths or perforations related to spray cryotherapy. Strictures developed in 11 of 108 patients (10.2%) but were present before spray cryotherapy in 3 of 11. Conclusions: This study suggests that endoscopic spray cryotherapy is safe, well tolerated and effective for early esophageal cancer in patients who are not candidates for conventional therapy.