Accuracy of artificial intelligence-assisted endoscopy in the diagnosis of gastric intestinal metaplasia: A systematic review and meta-analysis.

BACKGROUND AND AIMS: Gastric intestinal metaplasia is a precancerous disease, and a timely diagnosis is essential to delay or halt cancer progression. Artificial intelligence (AI) has found widespread application in the field of disease diagnosis. This study aimed to conduct a comprehensive evaluation of AI's diagnostic accuracy in detecting gastric intestinal metaplasia in endoscopy, compare it to endoscopists' ability, and explore the main factors affecting AI's performance. METHODS: The study followed the PRISMA-DTA guidelines, and the PubMed, Embase, Web of Science, Cochrane, and IEEE Xplore databases were searched to include relevant studies published by October 2023. We extracted the key features and experimental data of each study and combined the sensitivity and specificity metrics by meta-analysis. We then compared the diagnostic ability of the AI versus the endoscopists using the same test data. RESULTS: Twelve studies with 11,173 patients were included, demonstrating AI models' efficacy in diagnosing gastric intestinal metaplasia. The meta-analysis yielded a pooled sensitivity of 94% (95% confidence interval: 0.92-0.96) and specificity of 93% (95% confidence interval: 0.89-0.95). The combined area under the receiver operating characteristics curve was 0.97. The results of meta-regression and subgroup analysis showed that factors such as study design, endoscopy type, number of training images, and algorithm had a significant effect on the diagnostic performance of AI. The AI exhibited a higher diagnostic capacity than endoscopists (sensitivity: 95% vs. 79%). CONCLUSIONS: AI-aided diagnosis of gastric intestinal metaplasia using endoscopy showed high performance and clinical diagnostic value. However, further prospective studies are required to validate these findings.

Histopathology Features of H. pylori Gastritis Associated With Altered Lipid Profile: An Observational Study from a Tertiary Healthcare Center in North West Romania.

BACKGROUND/AIM: H. pylori infection can promote a systemic inflammatory syndrome, eventually leading to intestinal metaplasia and gastric cancer. The aim of our study was to investigate the possible association between dyslipidemia and histopathological features of H. pylori gastritis. PATIENTS AND METHODS: An observational, retrospective study was conducted over the period 2017-2022 on symptomatic patients with a positive rapid urease test. A total of 121 patients who underwent upper gastrointestinal endoscopy with stomach biopsy were enrolled in this study. Based on the updated Sydney System, we investigated the association between neutrophils, mononuclear cells, intestinal metaplasia, or gastric atrophy and altered lipid profiles. RESULTS: A high prevalence of H. pylori infection was noticed in the studied group upon the application of the rapid urease test, being associated with dyslipidemia regardless of patient sex. All the endoscopic diagnoses (acute, chronic, or atrophic chronic gastritis, metaplasia) correlated with the histopathological features. Mononuclear cells and metaplasia were more likely to be found in H. pylori-positive patients with dyslipidemia, which is consistent with acute and chronic inflammation caused by H. pylori in the gastric mucosa. CONCLUSION: Although our study was conducted on a small scale, it offers new insights and details regarding H. pylori infection and histopathological features. Mononuclear cells and metaplasia were associated with an altered lipid profile in H. pylori-positive patients. These findings warrant future investigation, such as the evolution of gastric biopsies and lipid profiles before and after eradication.

Stromal osseous metaplasia in urothelial carcinoma of the bladder: An unusual and challenging feature. A case report.

A 62-year-old male presented with pain and haematuria starting 3 months before. The computed tomography showed focal and mural bladder thickening with ureteropelvic dilatation. The following transurethral bladder resection revealed a high-grade muscle-invasive urothelial carcinoma. In the subsequent cystoprostatectomy we found the same tumour, but adding focal tumour-associated stromal osseous metaplasia. Ossifying metaplasia is an extremely rare feature in urothelial carcinoma, with a few reported cases and represents a diagnostic challenge, mimicking radiotherapy-induced sarcoma or sarcomatoid carcinoma.

Inhibition of cytosine 5-hydroxymethylation during progression of cancer precursor lesions in the uterine cervix.

Methylation and hydroxymethylation of cytosine moieties in CpG islands of specific genes are epigenetic processes shown to be involved in the development of cervical (pre)neoplastic lesions. We studied global (hydroxy)methylation during the subsequent steps in the carcinogenic process of the uterine cervix by using immunohistochemical protocols for the detection of 5-methylcytosine (5-mC) and 5-hydroxymethylcytosine (5-hmC) in paraffin-embedded tissues of the normal epithelia and (pre)malignant lesions. This approach allowed obtaining spatially resolved information of (epi)genetic alterations for individual cell populations in morphologically heterogeneous tissue samples. The normal ectocervical squamous epithelium showed a high degree of heterogeneity for both modifications, with a major positivity for 5-mC in the basal and parabasal layers in the ectocervical region, while 5-hmC immunostaining was even more restricted to the cells in the basal layer. Immature squamous metaplasia, characterized by expression of SOX17, surprisingly showed a decrease of 5-hmC in the basal compartments and an increase in the more superficial layers of the epithelium. The normal endocervical glandular epithelium showed a strong immunostaining reactivity for both modifications. At the squamocolumnar junctions, a specific 5-hmC pattern was observed in the squamous epithelium, resembling that of metaplasia, with the typical weak to negative reaction for 5-hmC in the basal cell compartment. The reserve cells underlying the glandular epithelium were also largely negative for 5-hmC but showed immunostaining for 5-mC. While the overall methylation status remained relatively constant, about 20% of the high-grade squamous lesions showed a very low immunostaining reactivity for 5-hmC. The (pre)malignant glandular lesions, including adenocarcinoma in situ (AIS) and adenocarcinoma showed a progressive decrease of hydroxymethylation with advancement of the lesion, resulting in cases with regions that were negative for 5-hmC immunostaining. These data indicate that inhibition of demethylation, which normally follows cytosine hydroxymethylation, is an important epigenetic switch in the development of cervical cancer.

Assessment of MUC5AC and MUC2 Immunoexpression in Glandular Odontogenic Cysts, Dentigerous Cysts, and Mucoepidermoid Carcinomas.

Glandular odontogenic cysts (GOCs) and dentigerous cysts may show mucous metaplasia. Central mucoepidermoid carcinoma is very rare and mostly associated with dental cysts. It is hypothesized that odontogenic cysts showing mucus differentiation in their lining, have a propensity to transform into MEC. The present study is the first attempt to explore the relationship between odontogenic cysts [GOCs and dentigerous cysts with mucus metaplasia (DCMM)] and MEC by evaluating immunoexpression of MUC5AC and MUC2. Immunoexpression of MUC5AC and MUC2 was evaluated semiquantitatively in GOCs (20 cases), DCMMs (20 cases), and MECs (20 cases). The percentage of positive cells, intensity, and localization of immunoexpression were assessed for each marker in all cases. Of GOCs, DCMMs, and MECs cases, 85%, 70%, and 80%, respectively, were immunopositive for MUC5AC. Strong cytoplasmic immunoreactivity for MUC5AC was noted, particularly in mucous cells present diffusely within MECs. However, the immunoreactivity was limited to the epithelial lining of GOCs and DCMMs. Most of the MECs (60%) showed more than 25% positivity for MUC5AC, followed by GOCs, and the least in DMMCs. Mild cytoplasmic and nuclear positivity of MUC2 was noted only in epithelial lining cells of 70% GOCs and 45% DCMMs. Whereas, 55% of MECs displayed moderate to strong cytoplasmic and membranous immunopositivity for MUC2 exclusively within mucous cells. As MECs showed strong MUC5AC immunoreactivity in mucous cells, immunoexpression of MUC5AC in odontogenic cysts with mucus cells can possibly explain the pathogenesis of MEC from cysts. However, the variable expression of MUC2 did not give any strong evidence regarding its role as a marker.

Novel Approach for Pancreas Transcriptomics Reveals the Cellular Landscape in Homeostasis and Acute Pancreatitis.

BACKGROUND & AIMS: Acinar cells produce digestive enzymes that impede transcriptomic characterization of the exocrine pancreas. Thus, single-cell RNA-sequencing studies of the pancreas underrepresent acinar cells relative to histological expectations, and a robust approach to capture pancreatic cell responses in disease states is needed. We sought to innovate a method that overcomes these challenges to accelerate study of the pancreas in health and disease. METHODS: We leverage FixNCut, a single-cell RNA-sequencing approach in which tissue is reversibly fixed with dithiobis(succinimidyl propionate) before dissociation and single-cell preparation. We apply FixNCut to an established mouse model of acute pancreatitis, validate findings using GeoMx whole transcriptome atlas profiling, and integrate our data with prior studies to compare our method in both mouse and human pancreas datasets. RESULTS: FixNCut achieves unprecedented definition of challenging pancreatic cells, including acinar and immune populations in homeostasis and acute pancreatitis, and identifies changes in all major cell types during injury and recovery. We define the acinar transcriptome during homeostasis and acinar-to-ductal metaplasia and establish a unique gene set to measure deviation from normal acinar identity. We characterize pancreatic immune cells, and analysis of T-cell subsets reveals a polarization of the homeostatic pancreas toward type-2 immunity. We report immune responses during acute pancreatitis and recovery, including early neutrophil infiltration, expansion of dendritic cell subsets, and a substantial shift in the transcriptome of macrophages due to both resident macrophage activation and monocyte infiltration. CONCLUSIONS: FixNCut preserves pancreatic transcriptomes to uncover novel cell states during homeostasis and following pancreatitis, establishing a broadly applicable approach and reference atlas for study of pancreas biology and disease.

Computer-aided diagnosis in real-time endoscopy for all stages of gastric carcinogenesis: Development and validation study.

OBJECTIVE: Using endoscopic images, we have previously developed computer-aided diagnosis models to predict the histopathology of gastric neoplasms. However, no model that categorizes every stage of gastric carcinogenesis has been published. In this study, a deep-learning-based diagnosis model was developed and validated to automatically classify all stages of gastric carcinogenesis, including atrophy and intestinal metaplasia, in endoscopy images. DESIGN: A total of 18,701 endoscopic images were collected retrospectively and randomly divided into train, validation, and internal-test datasets in an 8:1:1 ratio. The primary outcome was lesion-classification accuracy in six categories: normal/atrophy/intestinal metaplasia/dysplasia/early /advanced gastric cancer. External-validation of performance in the established model used 1427 novel images from other institutions that were not used in training, validation, or internal-tests. RESULTS: The internal-test lesion-classification accuracy was 91.2% (95% confidence interval: 89.9%-92.5%). For performance validation, the established model achieved an accuracy of 82.3% (80.3%-84.3%). The external-test per-class receiver operating characteristic in the diagnosis of atrophy and intestinal metaplasia was 93.4 ± 0% and 91.3 ± 0%, respectively. CONCLUSIONS: The established model demonstrated high performance in the diagnosis of preneoplastic lesions (atrophy and intestinal metaplasia) as well as gastric neoplasms.

Histopathologic evaluation of gastric intestinal metaplasia in non-neoplastic biopsy specimens: Accuracy and interobserver reliability among general pathologists and pathology residents.

OBJECTIVES: This study aimed to evaluate the accuracy and interobserver reliability of diagnosing and subtyping gastric intestinal metaplasia (IM) among general pathologists and pathology residents at a university hospital in Thailand, focusing on the challenges in the histopathologic evaluation of gastric IM for less experienced practitioners. METHODS: The study analyzed 44 non-neoplastic gastric biopsies, using a consensus diagnosis of gastrointestinal pathologists as the reference standard. Participants included 6 general pathologists and 9 pathology residents who assessed gastric IM and categorized its subtype (complete, incomplete, or mixed) on digital slides. After initial evaluations and receiving feedback, participants reviewed specific images of gastric IM, as agreed by experts. Following a one-month washout period, a reevaluation of the slides was conducted. RESULTS: Diagnostic accuracy, interobserver reliability, and time taken for diagnosis improved following training, with general pathologists showing higher accuracies than residents (median accuracy of gastric IM detection: 100 % vs. 97.7 %). Increased years of experience were associated with more IM detection accuracy (p-value<0.05). However, the overall median accuracy for diagnosing incomplete IM remained lower than for complete IM (86.4 % vs. 97.7 %). After training, diagnostic errors occurred in 6 out of 44 specimens (13.6 %), reported by over 40 % of participants. Errors involved omitting 5 slides with incomplete IM and 1 with complete IM, all showing a subtle presence of IM. CONCLUSIONS: The study highlights the diagnostic challenges in identifying incomplete gastric IM, showing notable discrepancies in accuracy and interobserver agreement. It underscores the need for better diagnostic protocols and training to enhance detection and management outcomes.

Papillary urothelial neoplasm of low malignant potential with osseous metaplasia in a 19-year-old chronic smoker: A case report with review of literature.

Urothelial tumors characteristically occur in elderly persons, more commonly in males with typical complaints of hematuria. Although few studies attempted to describe clinic-pathological features of urothelial malignancies in young patients, due to heterogeneity in the inclusion of age groups under "young patients" no reliable conclusions can be derived. Herein, we are describing an interesting case of papillary urothelial neoplasm of low malignant potential with osseous metaplasia in a 19-year-old chronic smoker young patient presented with chief complaints of abdominal pain with a review of the literature.

Genome-wide DNA methylation and transcriptomic patterns of precancerous gastric cardia lesions.

BACKGROUND: Intestinal metaplasia (IM) and intraepithelial neoplasia (IEN) are considered precursors of gastric cardia cancer (GCC). Here, we investigated the histopathologic and molecular profiles of precancerous gastric cardia lesions (PGCLs) and biomarkers for risk stratification of gastric cardia IM. METHODS: We conducted a hospital-based evaluation (n = 4578) for PGCL profiles in high-incidence and non-high-incidence regions for GCC in China. We next performed 850K methylation arrays (n = 42) and RNA-seq (n = 44) in tissues with PGCLs. We then examined the protein expression of candidate biomarker using immunohistochemistry. RESULTS: Of the 4578 participants, 791 were diagnosed with PGCLs (600 IM, 62 IM with IEN, and 129 IEN). We found that individuals from high-incidence regions (26.7%) were more likely to develop PGCLs than those from non-high-incidence areas (13.5%). DNA methylation and gene expression alterations, indicated by differentially methylated probes (DMPs) and differentially expressed genes (DEGs), exhibited a progressive increase from type I IM (DMP = 210, DEG = 24), type II IM (DMP = 3402, DEG = 129), to type III IM (DMP = 3735, DEG = 328), peaking in IEN (DMP = 47 373, DEG = 2278). Three DEGs with aberrant promoter methylation were identified, shared exclusively by type III IM and IEN. Of these DEGs, we found that OLFM4 expression appears in IMs and increases remarkably in IENs (P < .001). CONCLUSIONS: We highlight that type III IM and IEN share similar epigenetic and transcriptional features in gastric cardia and propose biomarkers with potential utility in risk prediction.

Sphingosine kinase 1-specific inhibitor PF543 reduces goblet cell metaplasia of bronchial epithelium in an acute asthma model.

Sphingosine kinase 1 (SPHK1) has been shown to play a key role in the pathogenesis of asthma where SPHK1-generated sphingosine-1-phosphate (S1P) is known to mediate innate and adaptive immunity while promoting mast cell degranulation. Goblet cell metaplasia (GCM) contributes to airway obstruction in asthma and has been demonstrated in animal models. We investigated the role of PF543, a SPHK1-specific inhibitor, in preventing the pathogenesis of GCM using a murine (C57BL/6) model of allergen-induced acute asthma. Treatment with PF543 before triple allergen exposure (DRA: House dust mite, Ragweed pollen, and Aspergillus) reduced inflammation, eosinophilic response, and GCM followed by reduced airway hyperreactivity to intravenous methacholine. Furthermore, DRA exposure was associated with increased expression of SPHK1 in the airway epithelium which was reduced by PF543. DRA-induced reduction of acetylated α-tubulin in airway epithelium was associated with an increased expression of NOTCH2 and SPDEF which was prevented by PF543. In vitro studies using human primary airway epithelial cells showed that inhibition of SPHK1 using PF543 prevented an allergen-induced increase of both NOTCH2 and SPDEF. siRNA silencing of SPHK1 prevented the allergen-induced increase of both NOTCH2 and SPDEF. NOTCH2 silencing was associated with a reduction of SPDEF but not that of SPHK1 upon allergen exposure. Our studies demonstrate that inhibition of SPHK1 protected allergen-challenged airways by preventing GCM and airway hyperreactivity, associated with downregulation of the NOTCH2-SPDEF signaling pathway. This suggests a potential novel link between SPHK1, GCM, and airway remodeling in asthma.NEW & NOTEWORTHY The role of SPHK1-specific inhibitor, PF543, in preventing goblet cell metaplasia (GCM) and airway hyperreactivity (AHR) is established in an allergen-induced mouse model. This protection was associated with the downregulation of NOTCH2-SPDEF signaling pathway, suggesting a novel link between SPHK1, GCM, and AHR.

Navigating the complexities of developing a classification of esophagogastric junction tumors suitable for preoperative setting.

Despite the worldwide decrease in the incidence of gastric cancer, the proportion of occurrence of carcinomas of the esophagogastric junction and proximal third of stomach is on the rise. The cause of this development is believed to lie in an increasing incidence of reflux esophagitis with Barrett´s metaplasia and successful eradication of Helicobacter pylori infection. The aim of this work is to present various views on the definition of the esophagogastric junction itself and to give an overview of tumor classification schemes being used (Fig. 2, Ref. 54). Keywords: gastric cancer, esophagogastric junction, definition, classification.

Neovascularization of native cardiac valves, and correlation with histopathologic, clinical, and radiologic features.

Native cardiac valves in the setting of chronic injury undergo remodeling that includes fibrous thickening and dystrophic calcification, as well as neovascularization, that result in abnormal valve function. In order to characterize the presence of neovascularization in valves, a retrospective review of 1246 sequentially reviewed native cardiac valves of all types was performed, with correlation with other histopathologic features, and clinical and echocardiographic findings. Neovascularization was present in 55.5% of cases, with the greatest prevalence amongst aortic valves. While microvasculature (representing capillaries, venules, and/or lymphatics) was at least present in all cases of valves with neovascularization, arterial vessels were never identified in valves without also the finding of concomitant microvasculature present. Patients with neovascularization had a greater mean age and body mass index compared to those without, and the proportions of cases with significant coronary artery disease, dyslipidemia, diabetes mellitus, rheumatic fever, and malignancy were greater in the setting of valves with neovascularization compared to cases without. The rate of neovascularization increased with degree of valve thickening and/or calcification, and stenosis; in contrast, neovascularization was observed at a greater rate with decreasing degrees of regurgitation. The prevalence rates of hemosiderin-laden macrophages, osseous metaplasia, chondromatous metaplasia, smooth muscle, and chronic inflammation were greater in valves with neovascularization compared to valves without. Neovascularization within native cardiac valves is a frequent histopathologic alteration associated with chronic valve disease, likely representing a constituent of structural remodeling that mediates and reflects chronic injury.

Mucosal Architectural Change is an Important Feature in Distinguishing Crohn's Disease From Others in Terminal Ileum Ulcer Biopsy.

BACKGROUND: Besides Crohn's disease (CD), there are a variety of other causes that can also lead to ulcerations in the terminal ileum. The purpose of this study was to identify useful diagnostic features for CD when evaluating terminal ileum biopsies in patients with endoscopic finding of ulcers. METHODS: Five hundred and seventy-one patients with endoscopic finding of ulcers were included in this retrospective study. Five main histological features were analysed, which were crypt irregularity, mucosal thickening, villous stromal widening (including villous atrophy), granulomas, and pseudopyloric gland metaplasia. Clinical and pathological features were determined by uni- and multivariable logistic regression. Then another independent cohort of 99 patients was established for verifying this nomogram. RESULTS: The crypt irregularity, mucosal thickening, and villous stromal widening were combined to be considered as one new variable named mucosal architectural change which was an independent variable in diagnosing CD. We found that mucosal architectural change, age <40 years, the presence of granulomas, and the presence of pseudopyloric gland metaplasia were independent factors for the pathological diagnosis of CD. Then nomogram was developed, with receiver operating characteristic (ROC) curve (area under the ROC curve [AUC] = 0.927) in training sets, and ROC curve (AUC = 0.913) in validation sets. CONCLUSIONS: We found mucosal architectural change is very helpful in distinguishing CD from non-CD patients. In the context of small biopsy which may lack full scope of changes, the model developed by combining these key features is valuable in predicting a diagnosis of CD, especially in younger patients (age <40 years).

Survivin as a potential biomarker for early diagnosis of the progression of precancerous lesions to gastric cancer.

BACKGROUND: Gastric cancer is a common cancer developed in a carcinogenesis process from precancerous lesions including chronic gastritis, intestinal metaplasia, and dysplasia. Survivin, an inhibitor-of-apoptosis protein, is associated with the initiation and progression of gastric cancer. The present study aimed to evaluate the immunohistochemical expression patterns of survivin and its relationship with early diagnosis of gastric cancer in Iranian patients. METHODS: In this retrospective case-control study, immunoexpression of survivin was investigated on sections obtained from formalin-fixed paraffin-embedded tissue blocks of 38 chronic gastritis, 32 intestinal metaplasia, 20 dysplasia, 28 gastric adenocarcinoma, and 22 controls. RESULTS: Survivin immunoexpression in chronic gastritis was higher than controls, but this difference was not statistically significant (P > 0.05). However, survivin immunoexpression had a steady significant increase from control and chronic gastritis to intestinal metaplasia to dysplasia to gastric adenocarcinoma (P < 0.05). Sensitivity, specificity, and area under the curve of survivin immunohistochemical test for the diagnosis of gastric cancer were 87.5%, 74.4%, and 0.85, respectively. Males had a significantly higher survivin expression than females (P < 0.001). Also, survivin expression was significantly higher in older patients than in younger ones (P < 0.001). CONCLUSION: It seems that the steady increase in survivin expression from different precancerous lesions to gastric adenocarcinoma suggests that survivin can be used as a potential biomarker for the prevention and early diagnosis of gastric cancer.

Gastric metaplasia as a precursor of nonconventional dysplasia in inflammatory bowel disease.

Gastric metaplasia in colonic mucosa with inflammatory bowel disease (IBD) develops as an adaptation mechanism. The association between gastric metaplasia and nonconventional and/or conventional dysplasia as precursors of colitis-associated colorectal cancer is unknown. To address this question, we retrospectively reviewed a series of 33 IBD colectomies to identify gastric metaplasia in 76 precursor lesions. We obtained 61 nonconventional and 15 conventional dysplasias. Among nonconventional dysplasia, 31 (50.8 %) were low-grade (LGD), 4 (6.5 %) were high-grade (HGD), 9 (14.8 %) had both LGD and HGD, and 17 (27.9 %) had no dysplasia (ND), while 14 (93 %) conventional dysplasias had LGD, and 1 (7 %) had LGD and HGD. Gastric metaplasia was assessed by concomitant immunoexpression of MUC5AC and loss of CDX2 staining. Expression of a p53-mut pattern was considered as a surrogate for gene mutation, and complete loss of MLH1 staining as presence of MLH1 hypermethylation. In nonconventional dysplasia, MUC5AC immunoexpression decreased as the degree of dysplasia increased, being 78 % in LGD and 39 % in HGD (p = 0.006). CDX2 was lost in epithelial glands with high expression of MUC5AC (p < 0.001). The p53-mut pattern was observed in 77 % HGD, 45 % LGD, and in 6 % with ND (p < 0.001). Neither nonconventional nor conventional dysplasia showed complete loss of MLH1 staining. Gastric metaplasia was also present in mucosa adjacent to nonconventional dysplasia with chronic changes or active inflammation. Our results show that gastric metaplasia appears in IBD-inflamed colon mucosa, it is the substrate of most nonconventional dysplasia and occurs prior to p53 alterations.

The presence of H. pylori in laparoscopic sleeve gastrectomy specimens is associated with increased mucosal thickness, presence of secondary follicles, increased chronic inflammation, and intestinal metaplasia.

Helicobacter pylori is putatively present in over half of the global human population and is recognized as a carcinogenic agent that increases the likelihood of infected patients developing gastric adenocarcinoma or gastric lymphoma. Although there are several means for testing for H. pylori, the gold standard remains the invasive histologic evaluation. The current most popular form of bariatric surgery is the laparoscopic sleeve gastrectomy (LSG) and is the only bariatric surgery which supplies a specimen for histologic evaluation. While non-invasive testing is effective in diagnosing and monitoring H. pylori infection, histological examination of biopsies and resections is the only way to grade chronic inflammation and evaluate specimens for additional pathologies such as intestinal metaplasia. The investigators evaluated 203 sequential LSG specimens collected from a major metropolitan hospital over the period of one year. Specimens were processed to paraffin, stained with hematoxylin and eosin, alcian blue, and immunohistochemistry to determine the presence of H. pylori, chronic inflammation, presence of secondary lymphoid follicles in the mucosa, mucosal thickness, and presence of intestinal metaplasia. Statistical analyses demonstrated a significant positive correlation among all factors examined. The overall positivity rate of H. pylori in LSG specimens was 18.2% but ranged from 6.9-23.8% depending on whether the treating clinician performed routine pre-surgical endoscopy. The presence of H. pylori was associated with a higher average chronic inflammation grade, intestinal metaplasia, thicker mucosa, and presence of lymphoid follicles with germinal centers in the mucosa.

Targeting Stem Cells and Dysplastic Features With Dual MEK/ERK and STAT3 Suppression in Gastric Carcinogenesis.

BACKGROUNDS & AIMS: Precancerous metaplasia progression to dysplasia can increase the risk of gastric cancers. However, effective strategies to specifically target these precancerous lesions are currently lacking. To address this, we aimed to identify key signaling pathways that are upregulated during metaplasia progression and critical for stem cell survival and function in dysplasia. METHODS: To assess the response to chemotherapeutic drugs, we used metaplastic and dysplastic organoids derived from Mist1-Kras mice and 20 human precancerous organoid lines established from patients with gastric cancer. Phospho-antibody array analysis and single-cell RNA-sequencing were performed to identify target cell populations and signaling pathways affected by pyrvinium, a putative anticancer drug. Pyrvinium was administered to Mist1-Kras mice to evaluate drug effectiveness in vivo. RESULTS: Although pyrvinium treatment resulted in growth arrest in metaplastic organoids, it induced cell death in dysplastic organoids. Pyrvinium treatment significantly downregulated phosphorylation of ERK and signal transducer and activator of transcription 3 (STAT3) as well as STAT3-target genes. Single-cell RNA-sequencing data analyses revealed that pyrvinium specifically targeted CD133+/CD166+ stem cell populations, as well as proliferating cells in dysplastic organoids. Pyrvinium inhibited metaplasia progression and facilitated the restoration of normal oxyntic glands in Mist1-Kras mice. Furthermore, pyrvinium exhibited suppressive effects on the growth and survival of human organoids with dysplastic features, through simultaneous blocking of the MEK/ERK and STAT3 signaling pathways. CONCLUSIONS: Through its dual blockade of MEK/ERK and STAT3 signaling pathways, pyrvinium can effectively induce growth arrest in metaplasia and cell death in dysplasia. Therefore, our findings suggest that pyrvinium is a promising chemotherapeutic agent for reprogramming the precancerous milieu to prevent gastric cancer development.

Cancer-Associated Fibroblast Induces Acinar-to-Ductal Cell Transdifferentiation and Pancreatic Cancer Initiation Via LAMA5/ITGA4 Axis.

BACKGROUND & AIMS: Pancreatic ductal adenocarcinoma (PDAC) is characterized by desmoplastic stroma surrounding most tumors. Activated stromal fibroblasts, namely cancer-associated fibroblasts (CAFs), play a major role in PDAC progression. We analyzed whether CAFs influence acinar cells and impact PDAC initiation, that is, acinar-to-ductal metaplasia (ADM). ADM connection with PDAC pathophysiology is indicated, but not yet established. We hypothesized that CAF secretome might play a significant role in ADM in PDAC initiation. METHODS: Mouse and human acinar cell organoids, acinar cells cocultured with CAFs and exposed to CAF-conditioned media, acinar cell explants, and CAF cocultures were examined by means of quantitative reverse transcription polymerase chain reaction, RNA sequencing, immunoblotting, and confocal microscopy. Data from liquid chromatography with tandem mass spectrometry analysis of CAF-conditioned medium and RNA sequencing data of acinar cells post-conditioned medium exposure were integrated using bioinformatics tools to identify the molecular mechanism for CAF-induced ADM. Using confocal microscopy, immunoblotting, and quantitative reverse transcription polymerase chain reaction analysis, we validated the depletion of a key signaling axis in the cell line, acinar explant coculture, and mouse cancer-associated fibroblasts (mCAFs). RESULTS: A close association of acino-ductal markers (Ulex europaeus agglutinin 1, amylase, cytokeratin-19) and mCAFs (α-smooth muscle actin) in LSL-KrasG12D/+; LSL-Trp53R172H/+; Pdx1Cre (KPC) and LSL-KrasG12D/+; Pdx1Cre (KC) autochthonous progression tumor tissue was observed. Caerulein treatment-induced mCAFs increased cytokeratin-19 and decreased amylase in wild-type and KC pancreas. Likewise, acinar-mCAF cocultures revealed the induction of ductal transdifferentiation in cell line, acinar-organoid, and explant coculture formats in WT and KC mice pancreas. Proteomic and transcriptomic data integration revealed a novel laminin α5/integrinα4/stat3 axis responsible for CAF-mediated acinar-to-ductal cell transdifferentiation. CONCLUSIONS: Results collectively suggest the first evidence for CAF-influenced acino-ductal phenotypic switchover, thus highlighting the tumor microenvironment role in pancreatic carcinogenesis inception.