UTILISATION OF THE CYTOSPONGE DEVICE AS A TOOL FOR RISK STRATIFICATION IN PATIENTS WITH BARRETT'S OESOPHAGUS WHO ARE OVERDUE ENDOSCOPIC SURVEILLANCE DUE TO THE COVID-19 PANDEMIC

Introduction: At the onset of the COVID-19 pandemic, all patients undergoing endoscopic surveillance for Barrett's Oesophagus (BE) in the UK were indefinitely postponed. As well as the potential for missed progression to dysplasia, the negative impact on patients' quality of life is immeasurable. The Cytosponge® is a minimally invasive cell sampling device which has been researched in screening for BE. We describe the first worldwide use of the Cytosponge® outside of a clinical trial to support the triage of BE patients unable to undergo endoscopic surveillance due to COVID-19. Aims and Methods: Consecutive patients with non-dysplastic BE (NDBE) or those deemed to be low risk after previous treatment for BErelated dysplasia, DBE (more than 18 months after completion of therapy with no visible BE and no intestinal metaplasia/dysplasia at last endoscopy) with no prior history of stenosis who were overdue endoscopy (OGD) were invited to have the Cytosponge®. The sample was analysed for TFF3 (a marker of intestinal metaplasia), cellular atypia and p53. Fisher's test was used to examine the association between the overall cytosponge result and its individual components with follow-up OGD outcomes. Results: To date, 153 patients (mean age 66 years, 126 male) have undergone the Cytosponge® procedure. The median maximal length of BE was 3cm (1-15cm). Three patients were unable to swallow the device and 19 (12%) needed a repeat procedure as no columnar cells were present suggesting that the sponge had not entered the stomach. 87 patients (80%) with NDBE had a either a low-risk result (TFF3 positive only – 62) or required a repeat Cytosponge® routinely (TFF3/atypia/ p53 negative – 25). The remaining 21 patients (20%) needed an OGD within 3 months, 17 of which have since had an OGD. Of these 17 patients, 4 had a new diagnosis of dysplasia (indefinite - 2, low grade dysplasia – 1, intramucosal cancer - 1) and 2 a new diagnosis of cancer. 18/87 patients in the low-risk NDBE cohort have undergone follow-up OGD (NDBE 17/18, high grade dysplasia 1/18). Of the 23 patients in the post-treatment BE cohort, 1 patient had a high-risk result and subsequent OGD confirmed HGD (Table 1). A high-risk cytosponge result and the presence of both p53 and typia were all associated with a positive OGD result. Over-expression of p53 appeared to be the most sensitive marker (Table 2). In treatment naive patients, a low-risk cytosponge result was closely associated with no dysplasia detected at follow-up OGD with a negative predictive value of 94%. Conclusions: Cytosponge® has proved to be a useful non-endoscopic tool for patients with BE under surveillance where OGD is not possible. Preliminary data are promising to help triage patients and may in turn offer a less invasive approach to monitoring patients compared to endoscopy, particuarly for low risk patients. (Table Presented) (Table Presented)

REAL-WORLD IMPLEMENTATION OF THE CYTOSPONGE TEST IN SECONDARY CARE FOR PATIENTS AT RISK OF EARLY OESOPHAGEAL CANCER

Introduction The CytospongeTM test is a non-endoscopic method to collect cells from the oesophagus and test for biomarkers of early oesophageal cancer and its precancerous form, Barrett's oesophagus. The real-world implementation pilots of the Cytosponge has been accelerated in response to the COVID-19 pandemic. At the onset of the pandemic, when endoscopy services were paused, guidelines from the British Society of Gastroenterology were updated to recommend the use of alternatives including the Cytosponge. In December 2020, NICE published a Medtech Innovation Briefing for use of the Cytosponge test as a triage tool for endoscopy to identify people at risk of oesophageal cancer. Aims & methods Implementation pilots were launched within the NHS in England and Scotland, as well as the Innovate UK-funded research project, Project DELTA. The Cytosponge test was offered to two patient cohorts as an alternative to endoscopy: (1) patients already diagnosed with Barrett's Oesophagus, and so in need of routine surveillance;and (2) patients referred from primary care with reflux symptoms. Samples were received, processed and analysed at the ISO 15189:2012 accredited laboratory at Cyted. Pathology reports were issued with TFF3, p53 and atypia biomarker results and clinical recommendations. Any reports positive for p53/atypia biomarkers were double reported. Here, we evaluate the real-world laboratory metrics for the Cytosponge test in secondary care. Results Between August 2020 and November 2021, Cytosponge tests were delivered to 5373 patients at 48 hospitals across England and Scotland. For 4842 diagnostic reports issued by mid-November, 2807 patients had Barrett's Oesophagus and 2034 reflux symptoms. For Barrett's surveillance, 2629 (93.7%) of patient samples had sufficient cellular material for analysis, including sampling the gastric cardia. Of these 324 (12.3%) exhibited cellular atypia (including uncertain significance), dysplasia, or aberrant p53 expression. These patients were recommended to have an endoscopy. Patients without evidence of atypia/dysplasia/p53 were recommended surveillance by Cytosponge or endoscopy after the recommended interval by clinical guidelines. In the symptomatic reflux cohort, 1854 (91.2%) patient samples had sufficient cellular material for analysis, including sampling the gastric cardia. Of these 185 (10.0%) exhibited intestinal metaplasia corroborated by TFF3 expression and a further 44 (2.4%) exhibited atypia/ dysplasia/p53. These patients were recommended to have an endoscopy. Otherwise, patients were recommended management according to symptoms. Discussion A high-quality centralised laboratory service has enabled accelerated real-world implementation of the Cytosponge in the secondary care setting. This has enabled triage and care of patients who have not been able to access endoscopy during the COVID-19 pandemic.

Diet Impact on Obesity beyond Calories and Trefoil Factor Family 2 (TFF2) as an Illustration: Metabolic Implications and Potential Applications.

Obesity is a health problem with increasing impacts on public health, economy and even social life. In order to reestablish the energy balance, obesity management focuses mainly on two pillars; exercise and diet. Beyond the contribution to the caloric intake, the diet nutrients and composition govern a variety of properties. This includes the energy balance-independent properties and the indirect metabolic effects. Whereas the energy balance-independent properties are close to "pharmacological" effects and include effects such as antioxidant and anti-inflammatory, the indirect metabolic effects represent the contribution a diet can have on energy metabolism beyond the caloric contribution itself, which include the food intake control and metabolic changes. As an illustration, we also described the metabolic implication and hypothetical pathways of the high-fat diet-induced gene Trefoil Factor Family 2. The properties the diet has can have a variety of applications mainly in pharmacology and nutrition and further explore the "pharmacologically" active food towards potential therapeutic applications.

Trefoil Factor Family Member 2 Expression as an Indicator of the Severity of the High-Fat Diet-Induced Obesity.

Trefoil Factor Family Member 2 (TFF2) belongs to TFF family peptides that includes TFF1, TFF2, TFF3. TFF2 is mainly known for its roles in the mucosal protection. In the context of obesity and high fat diet (HFD), Tff2 has been characterized as a HFD-induced gene. The knock-out of Tff2 in mice lead to the protection from HFD-induced obesity with a metabolic profile towards a negative energy balance. Such HFD-specific expression gives Tff2 a pattern worth exploring in biomedical research. Indeed, measuring TFF2/TFF2/Tff2 expression in biological samples following the ingestion of high-fat diet reflects the biological "responsiveness" to the lipids ingestion and would reflect the severity of obesity establishment afterwards. Such property could be explored for instance to screen animal models, evaluate the predisposition to HFD-induced obesity as well as in biomedical and clinical applications. Results might advance obesity research especially in terms of understanding lipid-induced signals, appetite control and adiposity storage.

Trefoil Factor Family Member 2: From a High-Fat-Induced Gene to a Potential Obesity Therapy Target.

Obesity has its epidemiological patterns continuously increasing. With controlling both diet and exercise being the main approaches to manage the energy metabolism balance, a high-fat (HF) diet is of particular importance. Indeed, lipids have a low satiety potential but a high caloric density. Thus, focusing on pharmacologically targetable pathways remains an approach with promising therapeutic potential. Within this context, trefoil factor family member 2 (Tff2) has been characterized as specifically induced by HF diet rather than low-fat diet. TFF2 has also been linked to diverse neurological mechanisms and metabolic patterns suggesting its role in energy balance. The hypothesis is that TFF2 would be a HF diet-induced signal that regulates metabolism with a focus on lipids. Within this review, we put the spotlight on key findings highlighting this line of thought. Importantly, the hypothetical mechanisms pointed highlight TFF2 as an important contributor to obesity development via increasing lipids intestinal absorption and anabolism. Therefore, an outlook for future experimental activities and evaluation of the therapeutic potential of TFF2 inhibition is given. Indeed, its knockdown or downregulation would contribute to an antiobesity phenotype. We believe this work represents an addition to our understanding of the lipidic molecular implications in obesity, which will contribute to develop therapies aiming to manage the lipidic metabolic pathways including the absorption, storage and metabolism via targeting TFF2-related pathways. We briefly discuss important relevant concepts for both basic and clinical researchers.

Trefoil Factor Family (TFF) Peptides and their Different Roles in the Mucosal Innate Immune Defense and More: An Update.

Mucous epithelia are protected by complex mucus barrier layers, which are part of the innate immune defense. Trefoil factor family peptides TFF1, TFF2, and TFF3 have lectin activities and are predominantly co-secreted together with mucins from these epithelia. TFF1 and TFF2 are mainly expressed in the gastric mucosa, whereas TFF3 is widely secreted from most mucous epithelia and their glands. TFF1 and TFF3 consist of a single TFF domain and an additional free 7th cysteine residue, whereas TFF2 contains two TFF domains. Systematic analyses of the molecular forms of TFFs gave new insights into their diverse molecular functions. TFF1 mainly exists as a monomer with an unusual free thiol group and only minor amounts form a disulfide-linked homodimer as well as heterodimers with gastrokine-2 and IgG-Fc-binding protein (FCGBP). TFF3 mainly forms a heterodimer with FCGBP in vivo, but also binds Deleted in Malignant Brain Tumors/gp340 (DMBT1gp340) in vitro. In contrast, TFF2 binds as a lectin to a conserved O-linked carbohydrate moiety of the mucin MUC6. Both FCGBP and DMBT1gp340 are secreted by most mucous epithelia and their glands and are involved in mucosal innate immunity. Thus, a new picture emerged pointing to functions of TFF3-FCGBP (and TFF1-FCGBP) for mucosal innate immune defense, e.g. supporting the clearing of the microorganisms. Such a function could be well be supported by DMBT1gp340. In contrast, the TFF2/MUC6 lectin complex probably physically stabilizes the inner adherent gastric mucus layer. Furthermore, there are indications that TFF3- FCGBP might also play a role in the blood vessels.