Glucagon-Like Peptide-1 Receptor Agonists Do Not Increase Aspiration During Upper Endoscopy in Patients With Diabetes.

BACKGROUND & AIMS: Glucagon-like peptide-1-receptor agonists (GLP1-RAs) have been associated with greater retention of gastric contents, however, there is minimal controlled, population-based data evaluating the potential adverse effects of GLP1-RA in the periprocedural setting. We aimed to determine if there is increased risk of aspiration and aspiration-related complications after upper endoscopy in patients using GLP1-RAs. METHODS: We used a nationwide commercial administrative claims database to conduct a retrospective cohort study of patients aged 18 to 64 with type 2 diabetes who underwent outpatient upper endoscopy from 2005 to 2021. We identified 6,806,046 unique upper endoscopy procedures. We compared claims for aspiration and associated pulmonary adverse events in the 14 days after upper endoscopy between users of GLP1-RAs, dipeptidyl peptidase 4 inhibitors (DPP4is), and chronic opioids. We adjusted for age, sex, Charlson Comorbidity score, underlying respiratory disease, and gastroparesis. RESULTS: We found that pulmonary adverse events after upper endoscopy are rare, ranging from 6 to 25 events per 10,000 procedures. When comparing GLP1-RAs with DPP4i, crude relative risks of aspiration (0.67; 95% CI, 0.25-1.75), aspiration pneumonia (0.95; 95% CI, 0.40-2.29), pneumonia (1.07; 95% CI, 0.62-1.86), or respiratory failure (0.75; 95% CI, 0.38-1.48) were not higher in patients prescribed a GLP1-RA. When comparing GLP1-RAs with opioids, crude relative risks were 0.42 (95% CI, 0.15-1.16) for aspiration, 0.60 (95% CI, 0.24-1.52) for aspiration pneumonia, 0.30 (95% CI, 0.19-0.49) for pneumonia, and 0.24 (95% CI, 0.13-0.45) for respiratory failure. These results were consistent across several sensitivity analyses. CONCLUSIONS: GLP1-RA use is not associated with an increased risk of pulmonary complications after upper endoscopy compared with DPP4i use in patients with type 2 diabetes.

Association between time from esophageal food impaction to endoscopy and adverse events.

BACKGROUND AND AIMS: Guidelines recommend emergent or urgent EGD for esophageal food impaction (EFI), but data on how time to EGD impacts the risk of adverse events remain limited. We determined whether EFI-to-EGD time was associated with adverse events. METHODS: In this retrospective cohort study of patients with endoscopically confirmed EFI, adverse events were classified as esophageal (mucosal tear, bleeding, perforation) or extraesophageal (aspiration, respiratory compromise, hypotension, arrhythmia). Esophageal perforation and extraesophageal adverse events requiring intensive care unit admission were classified as serious adverse events. Baseline characteristics, event details, and procedural details were compared between patients with and without adverse events. Multivariable logistic regression was performed to assess for an association between EFI-to-EGD time and adverse events. RESULTS: Of 188 patients with EFI, 22 (12%) had any adverse event and 2 (1%) had a serious adverse event. Patients with adverse events were older and more likely to have an esophageal motility disorder, to tolerate secretions at presentation, and to have a higher American Society of Anesthesiologists score. EFI-to-EGD time was similar in those with and without adverse events. On multivariable analysis, EFI-to-EGD time was not associated with adverse events (odds ratio, 1.00 [95% confidence interval, .97-1.04] for 1-hour increments; odds ratio, 1.03 [95% confidence interval, .86-1.24] for 6-hour increments). Results were similar after stratifying by eosinophilic esophagitis status and after adjusting for possible confounders. CONCLUSIONS: Because the time from EFI to EGD is not associated with adverse events, emergent EGD for EFI may be unnecessary, and other considerations may determine EGD timing.

Performing Esophageal Biopsies Is Safe During Upper Endoscopy for Food Impaction but Are Underperformed in Certain Populations.

BACKGROUND: Despite recommendations to perform esophageal biopsies during esophagogastroduodenoscopy (EGD) for esophageal food impaction to evaluate for eosinophilic esophagitis (EoE), endoscopists often forgo biopsies. There are minimal data on the risks of biopsies in this setting. AIMS: To determine the safety of performing biopsies during EGD for food impaction. METHODS: We conducted a retrospective cohort study of patients who presented to University of North Carolina Hospitals from 2014 to 2021 with endoscopically confirmed food impaction. Data were abstracted from the medical records. Baseline clinical characteristics, procedural details, and adverse events were compared between patients who did and did not undergo biopsy. Adverse events were classified as esophageal (mucosal tear, bleeding, perforation) or extra-esophageal (aspiration, respiratory compromise, hypotension, arrhythmia). RESULTS: Of 188 patients who underwent EGD for food impaction, 73 (39%) had biopsies taken. Older and non-White patients were less likely to be biopsied. None of the Black patients had biopsies taken. Only 2 (2.7%) of the 73 biopsied patients had an adverse event, and neither was related to the biopsies. Patients who were biopsied were less likely to experience adverse events. There were no differences in re-admission, ICU admission, or 30-day mortality between patients who were and were not biopsied. CONCLUSIONS: Esophageal biopsies remain underperformed during EGD for food impaction, especially in certain patient populations. Esophageal biopsies at the time of food impaction are unlikely to cause adverse events. Safety concerns should not preclude biopsies, and biopsies should be performed in the absence of extenuating circumstances.

Impact of cannabis use on presentation and treatment response in eosinophilic esophagitis.

Cannabis use is becoming increasingly common, both for recreational and medical purposes. However, there is a paucity of data regarding cannabis use in the context of eosinophilic esophagitis (EoE). We aimed to determine the impact of cannabis use on presentation and treatment response in EoE. To this end, we conducted a retrospective cohort study at a large academic medical center of newly diagnosed EoE patients age ≥ 12 years. Self-reported cannabis use status, baseline characteristics, and treatment response to topical corticosteroids and dietary therapy data were extracted. Bivariate and multivariable analyses were used to compare cannabis users and non-users at time of EoE diagnosis and to assess treatment response. Of 983 EoE patients, 80 reported using cannabis, with the majority reporting daily use and administration by inhalation. Baseline symptoms and peak eosinophil count were similar between cannabis users and non-users; cannabis users were less likely to have baseline endoscopic findings of exudates, edema, and stricture, and lower total Endoscopic Reference Score. On multivariable analysis, younger age, male sex, non-White race, and psychiatric diagnosis were independently associated with history of cannabis use at EoE presentation and stricture was independently associated with cannabis non-use. Post-treatment symptom and histologic responses were similar between cannabis users and non-users though there was a higher odds of post-treatment endoscopic inflammatory features with cannabis use. In conclusion, despite presenting with milder initial endoscopic findings, cannabis users exhibited greater inflammatory findings after treatment, highlighting a potential negative influence of cannabis use on EoE management.

Effects of Medical Cannabis on Use of Opioids and Hospital Visits by Patients With Painful Chronic Pancreatitis.

Pain is the most common and most debilitating aspect of chronic pancreatitis and is difficult to treat.1-3 Clinical management of painful chronic pancreatitis includes abstinence from alcohol and tobacco products, analgesic medications (including opioids), antidepressant medications, and pancreatic enzyme replacement.4-8 Medical cannabis has been proposed as a therapy for chronic pain and has shown some efficacy in neuropathic and cancer pain. In this study, we investigated the efficacy of medical cannabis on pain control for chronic pancreatitis.

The orphan nuclear receptor NR4A1 specifies a distinct subpopulation of quiescent myeloid-biased long-term HSCs.

Hematopoiesis is maintained throughout life by self-renewing hematopoietic stem cells (HSCs) that differentiate to produce both myeloid and lymphoid cells. The NR4A family of orphan nuclear receptors, which regulates cell fate in many tissues, appears to play a key role in HSC proliferation and differentiation. Using a NR4A1(GFP) BAC transgenic reporter mouse we have investigated NR4A1 expression and its regulation in early hematopoiesis. We show that NR4A1 is most highly expressed in a subset of Lin(-) Sca-1(+) c-Kit(+) CD48(-) CD150(+) long-term (LT) HSCs, and its expression is tightly associated with HSC quiescence. We also show that NR4A1 expression in HSCs is induced by PGE2, a known enhancer of stem cell engraftment potential. Finally, we find that both NR4A1(GFP+) and NR4A1(GFP-) HSCs successfully engraft primary and secondary irradiated hosts; however, NR4A1(GFP+) HSCs are distinctly myeloid-biased. These results show that NR4A1 expression identifies a highly quiescent and distinct population of myeloid-biased LT-HSCs.

Multiple Gastrointestinal Immune-Related Adverse Events From Immune Checkpoint Inhibitor Therapy.

INTRODUCTION: We aimed to describe immune-related adverse events (irAEs) affecting multiple organs of the gastrointestinal system in patients who received immune checkpoint inhibitors. METHODS: Within a 2,843 patient retrospective cohort consisting of patients with cancer treated with immune checkpoint inhibitors, we used the Electronic Medical Record Search Engine, an information retrieval system, to search free text in the medical record to identify patients with multiple gastrointestinal irAEs. RESULTS: Thirteen patients developed multiple gastrointestinal irAEs (0.46%). The most common patterns of multisystem gastrointestinal irAE were colitis + pancreatitis and colitis + enteritis. DISCUSSION: Multisystem gastrointestinal irAEs are rare but warrant further characterization and attention.

Transcriptional control of CBX5 by the RNA binding proteins RBMX and RBMXL1 maintains chromatin state in myeloid leukemia.

RNA binding proteins (RBPs) are key arbiters of post-transcriptional regulation and are found to be found dysregulated in hematological malignancies. Here, we identify the RBP RBMX and its retrogene RBMXL1 to be required for murine and human myeloid leukemogenesis. RBMX/L1 are overexpressed in acute myeloid leukemia (AML) primary patients compared to healthy individuals, and RBMX/L1 loss delayed leukemia development. RBMX/L1 loss lead to significant changes in chromatin accessibility, as well as chromosomal breaks and gaps. We found that RBMX/L1 directly bind to mRNAs, affect transcription of multiple loci, including CBX5 (HP1α), and control the nascent transcription of the CBX5 locus. Forced CBX5 expression rescued the RBMX/L1 depletion effects on cell growth and apoptosis. Overall, we determine that RBMX/L1 control leukemia cell survival by regulating chromatin state through their downstream target CBX5. These findings identify a mechanism for RBPs directly promoting transcription and suggest RBMX/L1, as well as CBX5, as potential therapeutic targets in myeloid malignancies.

IKZF2 Drives Leukemia Stem Cell Self-Renewal and Inhibits Myeloid Differentiation.

Leukemias exhibit a dysregulated developmental program mediated through both genetic and epigenetic mechanisms. Although IKZF2 is expressed in hematopoietic stem cells (HSCs), we found that it is dispensable for mouse and human HSC function. In contrast to its role as a tumor suppressor in hypodiploid B-acute lymphoblastic leukemia, we found that IKZF2 is required for myeloid leukemia. IKZF2 is highly expressed in leukemic stem cells (LSCs), and its deficiency results in defective LSC function. IKZF2 depletion in acute myeloid leukemia (AML) cells reduced colony formation, increased differentiation and apoptosis, and delayed leukemogenesis. Gene expression, chromatin accessibility, and direct IKZF2 binding in MLL-AF9 LSCs demonstrate that IKZF2 regulates a HOXA9 self-renewal gene expression program and inhibits a C/EBP-driven differentiation program. Ectopic HOXA9 expression and CEBPE depletion rescued the effects of IKZF2 depletion. Thus, our study shows that IKZF2 regulates the AML LSC program and provides a rationale to therapeutically target IKZF2 in myeloid leukemia.

Functional screen of MSI2 interactors identifies an essential role for SYNCRIP in myeloid leukemia stem cells.

The identity of the RNA-binding proteins (RBPs) that govern cancer stem cells remains poorly characterized. The MSI2 RBP is a central regulator of translation of cancer stem cell programs. Through proteomic analysis of the MSI2-interacting RBP network and functional shRNA screening, we identified 24 genes required for in vivo leukemia. Syncrip was the most differentially required gene between normal and myeloid leukemia cells. SYNCRIP depletion increased apoptosis and differentiation while delaying leukemogenesis. Gene expression profiling of SYNCRIP-depleted cells demonstrated a loss of the MLL and HOXA9 leukemia stem cell program. SYNCRIP and MSI2 interact indirectly though shared mRNA targets. SYNCRIP maintains HOXA9 translation, and MSI2 or HOXA9 overexpression rescued the effects of SYNCRIP depletion. Altogether, our data identify SYNCRIP as a new RBP that controls the myeloid leukemia stem cell program. We propose that targeting these RBP complexes might provide a novel therapeutic strategy in leukemia.

MSI2 is required for maintaining activated myelodysplastic syndrome stem cells.

Myelodysplastic syndromes (MDS) are driven by complex genetic and epigenetic alterations. The MSI2 RNA-binding protein has been demonstrated to have a role in acute myeloid leukaemia and stem cell function, but its role in MDS is unknown. Here, we demonstrate that elevated MSI2 expression correlates with poor survival in MDS. Conditional deletion of Msi2 in a mouse model of MDS results in a rapid loss of MDS haematopoietic stem and progenitor cells (HSPCs) and reverses the clinical features of MDS. Inversely, inducible overexpression of MSI2 drives myeloid disease progression. The MDS HSPCs remain dependent on MSI2 expression after disease initiation. Furthermore, MSI2 expression expands and maintains a more activated (G1) MDS HSPC. Gene expression profiling of HSPCs from the MSI2 MDS mice identifies a signature that correlates with poor survival in MDS patients. Overall, we identify a role for MSI2 in MDS representing a therapeutic target in this disease.

Musashi2 sustains the mixed-lineage leukemia-driven stem cell regulatory program.

Leukemia stem cells (LSCs) are found in most aggressive myeloid diseases and contribute to therapeutic resistance. Leukemia cells exhibit a dysregulated developmental program as the result of genetic and epigenetic alterations. Overexpression of the RNA-binding protein Musashi2 (MSI2) has been previously shown to predict poor survival in leukemia. Here, we demonstrated that conditional deletion of Msi2 in the hematopoietic compartment results in delayed leukemogenesis, reduced disease burden, and a loss of LSC function in a murine leukemia model. Gene expression profiling of these Msi2-deficient animals revealed a loss of the hematopoietic/leukemic stem cell self-renewal program and an increase in the differentiation program. In acute myeloid leukemia patients, the presence of a gene signature that was similar to that observed in Msi2-deficent murine LSCs correlated with improved survival. We determined that MSI2 directly maintains the mixed-lineage leukemia (MLL) self-renewal program by interacting with and retaining efficient translation of Hoxa9, Myc, and Ikzf2 mRNAs. Moreover, depletion of MLL target Ikzf2 in LSCs reduced colony formation, decreased proliferation, and increased apoptosis. Our data provide evidence that MSI2 controls efficient translation of the oncogenic LSC self-renewal program and suggest MSI2 as a potential therapeutic target for myeloid leukemia.

The Msi Family of RNA-Binding Proteins Function Redundantly as Intestinal Oncoproteins.

Members of the Msi family of RNA-binding proteins have recently emerged as potent oncoproteins in a range of malignancies. MSI2 is highly expressed in hematopoietic cancers, where it is required for disease maintenance. In contrast to the hematopoietic system, colorectal cancers can express both Msi family members, MSI1 and MSI2. Here, we demonstrate that, in the intestinal epithelium, Msi1 and Msi2 have analogous oncogenic effects. Further, comparison of Msi1/2-induced gene expression programs and transcriptome-wide analyses of Msi1/2-RNA-binding targets reveal significant functional overlap, including induction of the PDK-Akt-mTORC1 axis. Ultimately, we demonstrate that concomitant loss of function of both MSI family members is sufficient to abrogate the growth of human colorectal cancer cells, and Msi gene deletion inhibits tumorigenesis in several mouse models of intestinal cancer. Our findings demonstrate that MSI1 and MSI2 act as functionally redundant oncoproteins required for the ontogeny of intestinal cancers.