Journal of Gastroenterology最新文献

Metabolic dysfunction-associated steatohepatitis (MASH), previously known as nonalcoholic steatohepatitis (NASH), is a multifaceted liver disease characterized by inflammation and fibrosis that develops from simple steatosis. Immune and inflammatory pathways have a central role in the pathogenesis of MASH, yet, how to target immune pathways to treat MASH remains perplexed. This review emphasizes the intricate role that immune cells play in the etiology and pathophysiology of MASH and highlights their significance as targets for therapeutic approaches. It discusses both current strategies and novel therapies aimed at modulating the immune response in MASH. It also highlights challenges in liver-specific drug delivery, potential off-target effects, and difficulties in targeting diverse immune cell populations within the liver. This review is a comprehensive resource that integrates current knowledge with future perspectives in the evolving field of MASH, with the goal of driving forward progress in medical therapies designed to treat this complex liver disease.

Background: Intestinal fibrosis is one of the most frequent and severe complications of Crohn's disease. Accumulating studies have reported that adipose mesenchymal stem cell-derived small extracellular vesicles (AMSC-sEVs) could alleviate renal fibrosis, hepatic fibrosis, etc., while their potential for treating intestinal fibrosis remains uncertain. Therefore, this study aims to determine the therapeutic effects of AMSC-sEVs on intestinal fibrosis and identify the mechanisms underlying these effects.

Methods: AMSC-sEVs were characterized using transmission electron microscopy, nanoparticle tracking analysis, and western blot. Whether AMSC-sEVs exert antifibrotic effects was investigated in two different murine models of intestinal fibrosis. Besides, AMSC-sEVs were co-cultured with primary human fibroblasts and CCD18co during transforming growth factor (TGF)-β1 stimulation. Label-free proteomics and rescue experiments were performed to identify candidate molecules in AMSC-sEVs. Transcriptome sequencing revealed changes in mRNA levels among different groups. Lastly, proteins related to relevant signaling pathways were identified by western blotting, and their expression and activation status were assessed.

Results: AMSC-sEVs positively expressed CD63 and Alix and presented a classical "rim of a cup" and granule shape with approximately 43-100 nm diameter. AMSCs significantly alleviated intestinal fibrosis through secreted sEVs in vitro and in vivo. The milk fat globule-EGF factor 8 (MFGE8) was stably enriched in AMSC-sEVs and was an active compound contributing to the treatment of intestinal fibrosis by AMSCs. Mechanistically, AMSC-sEV-based therapies attenuated intestinal fibrosis by inhibiting the FAK/Akt signaling pathway.

Conclusions: MFGE8-containing AMSC-sEVs attenuate intestinal fibrosis, partly through FAK/Akt pathway inhibition.

Background: Achalasia is a rare motility disorder of the esophagus often accompanied by immune dysregulation, yet specific underlying mechanisms remain poorly understood.

Methods: We utilized Mendelian randomization (MR) to explore the causal effects of cytokine levels on achalasia, with cis-expression/protein quantitative trait loci (cis-eQTLs/pQTLs) for 47 cytokines selected from a genome-wide association study (GWAS) meta-analysis and GWAS data for achalasia obtained from FinnGen. For cytokines significantly linked to achalasia, we analyzed their plasma concentrations and expression differences in the lower esophageal sphincter (LES) using enzyme-linked immunosorbent assay and single-cell RNA sequencing (scRNA-seq) profiling, respectively. We further employed bioinformatics approaches to investigate underlying mechanisms.

Results: We revealed positive associations of circulating Eotaxin, macrophage inflammatory protein-1b (MIP1b), soluble E-selectin (SeSelectin) and TNF-related apoptosis-inducing ligand (TRAIL) with achalasia. When combining MR findings with scRNA-seq data, we observed upregulation of TRAIL (OR = 2.70, 95% CI, 1.20-6.07), encoded by TNFSF10, in monocytes and downregulation of interleukin-1 receptor antagonist (IL-1ra) (OR = 0.70, 95% CI 0.59-0.84), encoded by IL1RN, in FOS_macrophages in achalasia. TNFSF10^high monocytes in achalasia displayed activated type I interferon signaling, and IL1RN^low FOS_macrophages exhibited increased intercellular communications with various lymphocytes, together shaping the proinflammatory microenvironment of achalasia.

Conclusions: We identified circulating Eotaxin, MIP1b, SeSelectin and TRAIL as potential drug targets for achalasia. TNFSF10^high monocytes and IL1RN^low macrophages may play a role in the pathogenesis of achalasia.

Background & aim: SGLT2 inhibitors (SGLT2i) improve hepatic steatosis in patients with type 2 diabetes mellitus (T2DM) and MASLD. We aimed to investigate the impact of SGLT2i on the incidence of liver-related events and extrahepatic cancer compared to DPP4 inhibitors (DPP4i) in patients with T2DM and suspected MASLD using a medical claims database in Japan.

Methods: We conducted a retrospective study using a Japanese medical claims database. Among patients with T2DM who were prescribed SGLT2i or DPP4i (n = 1,628,656), patients with suspected MASLD were classified into SGLT2i (n = 4204) and DPP4i (n = 4204) groups. Effects of SGLT2i on the following outcomes were compared to DPP4i: (1) changes in HbA1c and ALT levels after 6 months, (2) changes in hepatic fibrosis index, and (3) the incidence of liver-related events/extrahepatic cancer over 12 months.

Results: After 6 months, DPP4i significantly decreased HbA1c levels compared to SGLT2i. In contrast, SGLT2i significantly decreased ALT levels compared to DPP4i. SGLT2i significantly decreased FIB-4 index compared to DPP4i over 12 months. Although no significant difference was observed in the incidence of overall liver-related events between the two groups, SGLT2i significantly reduced the incidence of esophageal varices (HR 0.12, 95%CI 0.01-0.95, P = 0.044). Moreover, SGLT2i significantly suppressed the incidence of extrahepatic cancer (HR 0.50, 95%CI 0.30-0.84, P = 0.009) compared to DPP4i.

Conclusion: SGLT2i was more beneficial than DPP4i in improving the hepatic inflammation and fibrosis indices. Moreover, SGLT2i suppressed the incidence of esophageal varices and extrahepatic cancer compared to DPP4i. SGLT2i may suppress life-threatening events in patients with T2DM and suspected MASLD.

Background: Since homologous recombination deficiency (HRD) is relatively uncommon in pancreatic cancer (PC), its impact on time-to-treatment failure (TTF) among patients undergoing systemic chemotherapy for unresectable and recurrent PC remains uncertain.

Methods: Among patients with unresectable and recurrent PC enrolled in the Center for Cancer Genomics and Advanced Therapeutics (C-CAT) database by July 2023, a total of 1394 patients who underwent first-line chemotherapy with either gemcitabine plus nab-paclitaxel (GnP) or FOLFIRINOX (FFX) and received tissue-based CGP tests after disease progression were included in this study. HRD was defined as the presence of germline or somatic genetic mutations in homologous recombination repair (HRR)-related genes such as ATM, BARD1, BRIP1, BRCA1/2, CHEK2, CDK12, PALB, and RAD51C/D. We investigated the correlation between HRD and TTF among patients treated with GnP and FFX.

Results: First-line chemotherapy consisted of GnP in 69% of the cases and FFX in 31%. The CGP tests used were NCC OncoPanel and FoundationOne CDx in 26% and 74%, respectively. HRR-related genetic abnormalities were identified in 107 patients (7.6%): BRCA2 (n = 51), ATM (n = 34), BRCA1 (n = 9), PALB2 (n = 9), among others. In the GnP cohort, the median TTF was comparable between the HRD and non-HRD groups (5.3 vs 4.6 months, P = 0.44). Conversely, in the FFX cohort, it was significantly longer in the HRD group compared to the non-HRD group (7.3 vs. 4.7 months, p < 0.01).

Conclusions: Our findings suggest that HRR-related genetic abnormalities might be predictive of TTF in platinum-based chemotherapy for PC.

Background: A substantial portion of gastric cancer (GC) is linked to Epstein-Barr virus (EBV) infection. The characteristics of this viral genome, such as specific viral strains and large structural variations, influence the progression of diseases like nasopharyngeal carcinoma and hematological malignancy. However, the EBV genomes from GC have not been thoroughly characterized.

Methods: Our study involved 849 consecutive GC patients diagnosed at Nagoya City University Hospital, Japan (NCU cohort). We detected EBV from formalin-fixed, paraffin-embedded sections using a novel direct PCR-based rapid detection method. Additionally, we analyzed 142 EBV whole genomes (125 newly sequenced) from GC, comparing them with 205 genomes from other EBV-associated diseases.

Results: We identified 32 (3.8%) patients associated with EBVaGC in the NCU cohort. Moreover, the direct PCR identified several GC specimens containing EBV-infected lymphocytes or their follicles. The dominant viral strain in GC was type 1 EBV, prevalent in most parts of the world, and no GC-specific strain was identified. We found no significant associations between single-nucleotide variants in the viral genome and GC. Structural variations of the EBV genome were infrequent in GC (4 cases, 2.1%), contrasting with EBV-associated hematological malignancy, which frequently carries large deletions.

Conclusions: This study is the first to uncover the genomic variations of EBV in GC. While EBV is definitively linked to GC, the characteristics of its genomes do not strongly correlate with disease development or progression. Our findings on viral genomes supplement the current understanding of human genomes in EBVaGC.

Background: The biological process of aging plays an important role in the progress of liver fibrosis. However, epidemiological evidence about the associations between advanced fibrosis and epigenetic age acceleration (EAA) among individuals with metabolic dysfunction-associated steatotic liver disease (MASLD) is limited.

Methods: We utilized publicly available DNA methylation data (GSE180474) for our analysis. Five EAA measures were calculated in this study, including IEAA, PhenoAA, GrimAA, DunedinPACE, and DNAmTLAA. Separate linear regression models were conducted to explore the associations between different fibrosis grades and each measure of EAA.

Results: A total of 325 participants were included in this study, with a mean (± SD) age of 48.56 ± 11.50 years. Of these participants, 64.6% with no fibrosis, 16.9% with bridging fibrosis, 11.1% with incomplete cirrhosis, and 7.4% with cirrhosis. After adjusting for demographics and medication status, MASLD individuals with advanced fibrosis were associated with a 5% increase in the pace of aging (DunedinPACE, β = 0.05, 95% CI: 0.03-0.07) and a 10% decrease in DNAmTLAA (β = -0.10, 95% CI: -0.13 to -0.07) compared those without fibrosis. Similarly, higher stages of fibrosis were associated with an increased pace of aging (DunedinPACE, β = 0.02, 95% CI: 0.01-0.03, P_trend < 0.001) and decreased DNAmTLAA (β = -0.05, 95% CI: -0.07 to -0.04, P_trend < 0.001). However, no significant association was found between advanced fibrosis and IEAA, PhenoAA, and GrimAA.

Conclusions: Our findings suggest that advanced fibrosis was associated with an accelerated pace of aging, as measured by the third-generation EA measure DunedinPACE, and shorter telomere length, captured by DNAmTLAA, among individuals with MASLD. This finding has potential prognostic implications and suggests EAA may serve as a surrogate marker of therapeutic efficacy in MASLD.

Background: Although imatinib (IM) and subsequent tyrosine kinase inhibitors (TKIs) significantly improve the prognosis of GIST patients by delaying metastasis and recurrence, most patients experience limited efficacy due to toxicity and secondary resistance. We evaluated Yes-associated protein (YAP), a coactivator of the Hippo pathway accounting for IM resistance and aggressive GIST phenotypes, in GISTs. The degradation of YAP is mediated by FBXW7, and FBXW7 predicts recurrence and IM efficacy for GIST patients. Here, we aimed to identify the potential of YAP as a prognostic marker for patients with GISTs, and the molecular mechanism of FBXW7-YAP pathway in GIST cells.

Methods: We measured YAP expression in 167 GIST cases using immunohistochemical staining, correlated its expression levels with clinicopathological features, and the molecular mechanism underlying the FBXW7-YAP pathway was further examined in vitro and in vivo.

Results: Compared to 80 (47.9%) cases in the low YAP expression group, 87 (52.1%) cases with high YAP expression associated with a poorer prognosis in terms of overall survival (P = 0.004) and recurrence-free survival (P = 0.003). YAP expression was identified as a significant independent factor affecting the 5-year overall survival (P = 0.005) and recurrence-free survival rates (P = 0.007). Moreover, YAP was directly targeted by FBXW7 to affect proliferation, invasion, and migration in GIST cells. High YAP expression correlated with FBXW7 deficiency, as shown in xenograft and metastasis mouse models.

Conclusions: YAP expression serves as a predictive marker of recurrence for GIST patients with curative resection, highlighting its potential as a novel therapeutic target that warrants further investigation.