Impaired glycosylation of gastric mucins drives gastric tumorigenesis and serves as a novel therapeutic target.

BACKGROUND: Gastric cancer is often accompanied by a loss of MUC6, but its pathogenic role in gastric carcinogenesis remains unclear. METHOD: Muc6 knockout (Muc6-/-) mice and Muc6-dsRED mice were newly generated. Tff1Cre, Golph3-/-, R26-Golgi-mCherry, Hes1flox/flox, Cosmcflox/flox, A4gnt-/- mice were also used. Histology, DNAs and RNAs, proteins, and sugar chains were analyzed by whole exon DNA sequence, RNA sequence, immunohistochemistry, lectin-binding assays, and LC-MS analysis. Gastric organoids and cell lines were used for in vitro assays and xenograft experiments. RESULT: Deletion of Muc6 in mice spontaneously causes pan-gastritis and invasive gastric cancers. Muc6-deficient tumor growth was dependent on MAPK activation, mediated by Golgi stress-induced upregulation of GOLPH3. Glycomic profiling revealed aberrant expression of mannose-rich N-linked glycans in gastric tumors, detected with Banana lectin in association with lack of MUC6 expression. We identified a precursor of clusterin as a binding partner of mannose glycans. MAPK activation, Golgi stress responses, aberrant mannose expression are found in a separate Cosmc- and A4gnt-deficient mouse models which lack normal O-glycosylation. Banana lectin-drug conjugates proved an effective treatment for mannose-rich murine and human gastric cancer. CONCLUSION: We propose that Golgi stress responses and aberrant glycans are important drivers of, and promising new therapeutic targets for gastric cancer.

Upper gastrointestinal involvement of Behçet's disease in Japan: endoscopic findings and clinical features.

AIM: Behçet's disease (BD) can involve any gastrointestinal (GI) tract site. We analyzed the characteristics, risk factors, and treatment responses to upper GI (UGI) involvement in patients with BD. METHODS: This retrospective cohort study analyzed UGI findings in 101 patients with BD who underwent endoscopy between April 2005 and December 2022 at the University of Tokyo Hospital. The patients were divided into two groups based on the presence or absence of UGI findings. Patient backgrounds, clinical symptoms, colonoscopy (CS) findings, and blood test findings were compared between the groups. RESULTS: In total, 18.8% (19/101) of the patients had UGI lesions. The prevalence rates in the esophagus, stomach, and duodenum were 6.9%, 6.9%, and 8.9%, respectively. Of these 19 patients, BD treatment were intensified in 10 (52.6%) patients after esophagogastroduodenoscopy (EGD), and all showed improvement in symptoms or endoscopic findings. In the multivariate analysis, symptoms (OR: 37.1, P < 0.001), CRP > 1 mg/dL (OR: 11.0, P = 0.01), and CS findings (OR: 5.16, P = 0.04) were independent predictors of UGI involvement in BD patients. The prediction model for UGI involvement using these three factors was highly accurate, with an AUC of 0.899 on the ROC curve. In the subgroup analysis of intestinal BD, symptoms (OR: 12.8, P = 0.01) and ESR > 20 mm/h (OR: 11.5, P = 0.007) were independent predictors. CONCLUSIONS: EGD should be conducted in BD patients with high CRP, GI symptoms, and lower GI involvement, which leads to better management of BD in terms of improving symptoms and endoscopic findings.

Loss of Grem1-lineage chondrogenic progenitor cells causes osteoarthritis.

Osteoarthritis (OA) is characterised by an irreversible degeneration of articular cartilage. Here we show that the BMP-antagonist Gremlin 1 (Grem1) marks a bipotent chondrogenic and osteogenic progenitor cell population within the articular surface. Notably, these progenitors are depleted by injury-induced OA and increasing age. OA is also caused by ablation of Grem1 cells in mice. Transcriptomic and functional analysis in mice found that articular surface Grem1-lineage cells are dependent on Foxo1 and ablation of Foxo1 in Grem1-lineage cells caused OA. FGFR3 signalling was confirmed as a promising therapeutic pathway by administration of pathway activator, FGF18, resulting in Grem1-lineage chondrocyte progenitor cell proliferation, increased cartilage thickness and reduced OA. These findings suggest that OA, in part, is caused by mechanical, developmental or age-related attrition of Grem1 expressing articular cartilage progenitor cells. These cells, and the FGFR3 signalling pathway that sustains them, may be effective future targets for biological management of OA.

Engineered bacteria detect tumor DNA.

Synthetic biology has developed sophisticated cellular biosensors to detect and respond to human disease. However, biosensors have not yet been engineered to detect specific extracellular DNA sequences and mutations. Here, we engineered naturally competent Acinetobacter baylyi to detect donor DNA from the genomes of colorectal cancer (CRC) cells, organoids, and tumors. We characterized the functionality of the biosensors in vitro with coculture assays and then validated them in vivo with sensor bacteria delivered to mice harboring colorectal tumors. We observed horizontal gene transfer from the tumor to the sensor bacteria in our mouse model of CRC. This cellular assay for targeted, CRISPR-discriminated horizontal gene transfer (CATCH) enables the biodetection of specific cell-free DNA.

Association of probiotic use with nivolumab effectiveness against various cancers: A multicenter retrospective cohort study.

BACKGROUND: Previous studies have revealed an association between probiotic use and effectiveness of immune checkpoint inhibitors in renal and lung cancers. However, little is known regarding other cancers, including gastrointestinal cancer. METHODS: To address this issue, we conducted a multicenter retrospective cohort study and the duration of nivolumab treatment for various cancers was compared between probiotic users and non-users. RESULTS AND CONCLUSIONS: In total, 488 patients who received nivolumab therapy were included. In all cancers, no significant differences in treatment duration of nivolumab were observed between probiotic users and non-users (median 62.0 vs. 56.0, hazard ratio = 1.02, p = 0.825), whereas probiotic use, compared with non-use, in patients with gastric cancer was significantly associated with a longer duration of nivolumab treatment (55.0 vs. 31.0 days, hazard ratio = 0.69, p = 0.039). In conclusion, probiotics may improve the response to nivolumab and potentially prolong progression-free survival in patients with gastric cancer.

The Association between Diverticular Rebleeding and Early-Morning Blood Pressure and Surge: A Prospective Observational Trial.

INTRODUCTION: Colonic diverticular bleeding is the major cause of lower gastrointestinal bleeding. Hypertension is a major risk factor for diverticular rebleeding. Direct evidence of an association between actual 24-h blood pressure (BP) and rebleeding is lacking. Therefore, we analyzed the association between 24-h BP and diverticular rebleeding. METHODS: We performed a prospective observational cohort trial involving hospitalized patients with colonic diverticular bleeding. We performed 24-h BP measurements (ambulatory BP monitoring [ABPM]) in the patients. The primary outcome was diverticular rebleeding. We evaluated the 24-h BP difference and the morning and pre-awaking BP surge between rebleeding and non-rebleeding patients. Morning BP surge was defined as early-morning systolic BP minus the lowest night systolic BP >45 mm Hg (highest quartile of morning BP surge). The pre-awaking BP surge was defined as the difference between morning BP and pre-awaking BP. RESULTS: Of 47 patients, 17 were excluded, leaving 30 who underwent ABPM. Of the 30 patients, 4 (13.33%) had rebleeding. The mean 24-h systolic and diastolic BP were 125.05 and 76.19 mm Hg in rebleeding patients and 129.98 and 81.77 mm Hg in non-rebleeding patients, respectively. Systolic BP at 5:00 (difference -23.53 mm Hg, p = 0.031) and 11:30 (difference -31.48 mm Hg, p = 0.006) was significantly lower in rebleeding patients than in non-rebleeding patients. Diastolic BP at 2:30 (difference -17.75 mm Hg, p = 0.023) and 5:00 (difference -16.12 mm Hg, p = 0.043) was significantly lower in rebleeding patients than in non-rebleeding patients. A morning surge was observed in one rebleeding patient and no non-rebleeding patients. The pre-awaking surge was significantly higher in rebleeding patients (28.44 mm Hg) than in non-rebleeding patients (9.30 mm Hg) (p = 0.015). CONCLUSION: Lower BP in the early-morning and a higher pre-awaking surge were risk factors for diverticular rebleeding. A 24-h ABPM can identify these BP findings and reduce the risk of rebleeding by enabling interventions in patients with diverticular bleeding.

Loss of Grem1-articular cartilage progenitor cells causes osteoarthritis.

Osteoarthritis (OA), which carries an enormous disease burden across the world, is characterised by irreversible degeneration of articular cartilage (AC), and subsequently bone. The cellular cause of OA is unknown. Here, using lineage tracing in mice, we show that the BMP-antagonist Gremlin 1 (Grem1) marks a novel chondrogenic progenitor (CP) cell population in the articular surface that generates joint cartilage and subchondral bone during development and adulthood. Notably, this CP population is depleted in injury-induced OA, and with age. OA is also induced by toxin-mediated ablation of Grem1 CP cells in young mice. Transcriptomic analysis and functional modelling in mice revealed articular surface Grem1-lineage cells are dependent on Foxo1; ablation of Foxo1 in Grem1-lineage cells led to early OA. This analysis identified FGFR3 signalling as a therapeutic target, and injection of its activator, FGF18, caused proliferation of Grem1-lineage CP cells, increased cartilage thickness, and reduced OA pathology. We propose that OA arises from the loss of CP cells at the articular surface secondary to an imbalance in progenitor cell homeostasis and present a new progenitor population as a locus for OA therapy.

Risk and preventive factors of early-onset colorectal neoplasms: endoscopic and histological database analysis.

BACKGROUND AND AIM: The incidence of early-onset colorectal neoplasms has been increasing in both Western and Eastern countries. However, the risks and preventive factors for these neoplasms in Eastern countries remain unclear. METHODS: The data of 5580 patients who underwent colonoscopy between 2016 and 2021 were retrospectively evaluated. The primary outcome was advanced colorectal neoplasm (ACRN), defined as advanced adenomas (adenoma ≥10 mm, or with high-grade dysplasia or villous component) or adenocarcinoma. The clinical factors associated with ACRNs were determined for each age category (≤50 and >50 years), and the differences between the two categories were assessed. Odds ratios adjusted for age and sex were calculated. RESULTS: Among 1001 patients (age ≤50 years), ACRN was found in 94 (9.4%). In this younger category, male sex (adjusted odds ratio [aOR]:2.34, 95% confidence interval [CI]:1.51-3.63) and a family history of colorectal cancer (aOR:2.14, 95% CI:1.17-3.89) were significantly associated with higher odds of developing ACRNs. ACRNs were detected in 726 (15.9%) of 4579 patients (age >50 years). In the older age category, smoking (aOR:1.32, 95% CI:1.08-1.63) was significantly associated with a higher risk of ACRNs. Exercise of >3.5 metabolic equivalent of task (METs) (aOR,0.80; 95% CI:0.67-0.96) was significantly associated with a lower risk of ACRNs. CONCLUSION: The development of early-onset ACRNs was primarily associated with congenital factors, whereas that of late-onset ACRNs was associated with acquired ones. Colonoscopy is recommended for young male patients, particularly for those with a family history of colorectal cancer.

Efficacy of Early Video Capsule Endoscopy for Acute Overt Lower Gastrointestinal Bleeding with Colonic Diverticulosis: A Prospective Observational Study.

BACKGROUND/AIMS: Although most patients with presumptive colonic diverticular bleeding (CDB) do not undergo a small bowel investigation in clinical practice, no prospective study supports this management. We evaluated the utility of early small bowel capsule endoscopy (CE) after negative colonoscopy results. METHODS: This prospective study evaluated the diagnostic yield of early small bowel CE (≤3 days from visit) for consecutive patients with acute-onset hematochezia, when colonoscopy found colonic diverticulosis but did not identify the definite bleeding source (n = 51; presumptive CDB). As a matched control for comparing clinical outcomes, presumptive CDB patients without CE (n = 51) were retrospectively extracted. RESULTS: On CE for the prospective cohort, the rates of total positive findings, P2 findings (high bleeding potential according to the P classification), and blood pooling in the colon were 57%, 12% (ulceration, 8%; angioectasia, 4%), and 24%, respectively. The rates of rebleeding within 30 and 365 days were 16% and 29% in the prospective cohort with CE, respectively, and were not significantly different from those in the retrospective cohort without CE (10% and 25%, respectively). In addition, thromboembolism and mortality within 30 and 365 days were not significantly different between those with and without CE. CONCLUSION: Early CE detected a suspected small bowel bleeding source in 12% of acute-onset presumptive CDB patients but did not significantly improve major clinical outcomes. Therefore, routine CE is unnecessary for presumptive CDB patients after colonoscopy (UMIN000026676).

Inhibiting SCAP/SREBP exacerbates liver injury and carcinogenesis in murine nonalcoholic steatohepatitis.

Enhanced de novo lipogenesis mediated by sterol regulatory element-binding proteins (SREBPs) is thought to be involved in nonalcoholic steatohepatitis (NASH) pathogenesis. In this study, we assessed the impact of SREBP inhibition on NASH and liver cancer development in murine models. Unexpectedly, SREBP inhibition via deletion of the SREBP cleavage-activating protein (SCAP) in the liver exacerbated liver injury, fibrosis, and carcinogenesis despite markedly reduced hepatic steatosis. These phenotypes were ameliorated by restoring SREBP function. Transcriptome and lipidome analyses revealed that SCAP/SREBP pathway inhibition altered the fatty acid (FA) composition of phosphatidylcholines due to both impaired FA synthesis and disorganized FA incorporation into phosphatidylcholine via lysophosphatidylcholine acyltransferase 3 (LPCAT3) downregulation, which led to endoplasmic reticulum (ER) stress and hepatocyte injury. Supplementation with phosphatidylcholines significantly improved liver injury and ER stress induced by SCAP deletion. The activity of the SCAP/SREBP/LPCAT3 axis was found to be inversely associated with liver fibrosis severity in human NASH. SREBP inhibition also cooperated with impaired autophagy to trigger liver injury. Thus, excessively strong and broad lipogenesis inhibition was counterproductive for NASH therapy; this will have important clinical implications in NASH treatment.

Clinicopathological Features of Gastric Cancer with Autoimmune Gastritis.

Most gastric cancers develop in patients with chronic gastritis. Chronic gastritis can be classified into two major subtypes: Helicobacter pylori (H. pylori)-induced gastritis and autoimmune gastritis (AIG). Whereas H. pylori-related gastric cancers are more common and have been extensively investigated, the clinicopathological features of gastric cancer with autoimmune gastritis are unclear. Patients diagnosed with gastric cancer and hospitalized in the University Tokyo Hospital from 1998 to 2017 were enrolled. Diagnosis of autoimmune gastritis was based on positivity for serum anti-parietal cell antibody (APCA). We evaluated mucin expression and immune cell infiltration by immunohistochemical staining for MUC5AC, MUC6, PD-L1, CD3, CD11, Foxp3, and PD1. We also examined the presence of bacterial taxa that are reportedly enriched in AIG. Survival analyses of recurrence and 5-year mortality were also performed. In total, 261 patients (76 APCA-positive and 185 APCA-negative) were analyzed. Immunohistochemical staining in the matched cohort showed that AIG-related gastric cancer had higher MUC5AC expression (p = 0.0007) and MUC6 expression (p = 0.0007). Greater infiltration of CD3-positive (p = 0.001), Foxp3-positive (p < 0.001), and PD1-positive cells (p = 0.001); lesser infiltration of CD11b-positive (p = 0.005) cells; and a higher prevalence of Bacillus cereus (p = 0.006) were found in AIG-related gastric cancer patients. The cumulative incidences of gastric cancer recurrence were 2.99% at 2 years, 15.68% at 6 years, and 18.81% at 10 years in APCA-positive patients; they were 12.79% at 2 years, 21.35% at 6 years, and 31.85% at 10 years in APCA-negative patients. The cumulative incidences of mortality were 0% at 3 years and 0% at 5 years in APCA-positive patients; they were 1.52% at 3 years and 2.56% at 5 years in APCA-negative patients. We identified molecular differences between AIG and non-AIG gastric cancer. Differences in T-cell populations and the gastric microbiota may contribute to the pathogenesis of gastric cancers and potentially affect the response to immunotherapy.

Chemoprevention for Colorectal Cancers: Are Chemopreventive Effects Different Between Left and Right Sided Colorectal Cancers?

BACKGROUND AND AIMS: Recent studies have suggested that right- and left-sided colorectal cancers (CRCs) are molecularly distinct. In this study, we examined the association between the risk of right- and left-sided CRC and drug use to estimate their chemopreventive effects METHODS: This multicenter retrospective cohort study was conducted using the data of hospitalized patients between 2014 and 2019 from nine hospital databases. The primary outcomes were right- and left-sided CRC. We evaluated the association of CRCs with drug use and clinical factors. Odds ratios adjusted for age, sex, Charlson Comorbidity Index scores, and smoking status were calculated. We also compared the transcriptional profiling in precancerous lesions, including sessile serrated lesions (SSLs) RESULTS: A total of 307,938 patients, including 2745 with right-sided CRC and 4819 with left-sided CRC, were analyzed. The use of nonsteroidal anti-inflammatory drugs (NSAIDs), aspirin, cyclooxygenase-2 inhibitors, and steroids was associated with a lower risk of both right- and left-sided CRCs. In contrast, statins, other lipid-lowering agents, and metformin were associated with a lower risk of left-sided CRC. Transcriptomic analysis showed that SSL, which predominantly develops in the right colon, was associated with a lower expression of lipid metabolism-related genes. CONCLUSIONS: Targeting lipid metabolism may be useful for chemoprevention of left-sided CRCs, while development of right-sided CRCs may be independent of this pathway.

Machine learning-based personalized prediction of gastric cancer incidence using the endoscopic and histologic findings at the initial endoscopy.

BACKGROUND AND AIMS: Accurate risk stratification for gastric cancer is required for optimal endoscopic surveillance in patients with chronic gastritis. We aimed to develop a machine learning (ML) model that incorporates endoscopic and histologic findings for an individualized prediction of gastric cancer incidence. METHODS: We retrospectively evaluated 1099 patients with chronic gastritis who underwent EGD and biopsy sampling of the gastric mucosa. Patients were randomly divided into training and test sets (4:1). We constructed a conventional Cox proportional hazard model and 3 ML models. Baseline characteristics, endoscopic atrophy, and Operative Link on Gastritis-Intestinal Metaplasia Assessment (OLGIM)/Operative Link on Gastritis Assessment (OLGA) stage at initial EGD were comprehensively assessed. Model performance was evaluated using Harrel's c-index. RESULTS: During a mean follow-up of 5.63 years, 94 patients (8.55%) developed gastric cancer. The gradient-boosting decision tree (GBDT) model achieved the best performance (c-index from the test set, .84) and showed high discriminative ability in stratifying the test set into 3 risk categories (P < .001). Age, OLGIM/OLGA stage, endoscopic atrophy, and history of malignant tumors other than gastric cancer were important predictors of gastric cancer incidence in the GBDT model. Furthermore, the proposed GBDT model enabled the generation of a personalized cumulative incidence prediction curve for each patient. CONCLUSIONS: We developed a novel ML model that incorporates endoscopic and histologic findings at initial EGD for personalized risk prediction of gastric cancer. This model may lead to the development of effective and personalized follow-up strategies after initial EGD.

The Origin and Contribution of Cancer-Associated Fibroblasts in Colorectal Carcinogenesis.

BACKGROUND & AIMS: Cancer-associated fibroblasts (CAFs) play an important role in colorectal cancer (CRC) progression and predict poor prognosis in CRC patients. However, the cellular origins of CAFs remain unknown, making it challenging to therapeutically target these cells. Here, we aimed to identify the origins and contribution of colorectal CAFs associated with poor prognosis. METHODS: To elucidate CAF origins, we used a colitis-associated CRC mouse model in 5 different fate-mapping mouse lines with 5-bromodeoxyuridine dosing. RNA sequencing of fluorescence-activated cell sorting-purified CRC CAFs was performed to identify a potential therapeutic target in CAFs. To examine the prognostic significance of the stromal target, CRC patient RNA sequencing data and tissue microarray were used. CRC organoids were injected into the colons of knockout mice to assess the mechanism by which the stromal gene contributes to colorectal tumorigenesis. RESULTS: Our lineage-tracing studies revealed that in CRC, many ACTA2+ CAFs emerge through proliferation from intestinal pericryptal leptin receptor (Lepr)+ cells. These Lepr-lineage CAFs, in turn, express melanoma cell adhesion molecule (MCAM), a CRC stroma-specific marker that we identified with the use of RNA sequencing. High MCAM expression induced by transforming growth factor ß was inversely associated with patient survival in human CRC. In mice, stromal Mcam knockout attenuated orthotopically injected colorectal tumoroid growth and improved survival through decreased tumor-associated macrophage recruitment. Mechanistically, fibroblast MCAM interacted with interleukin-1 receptor 1 to augment nuclear factor κB-IL34/CCL8 signaling that promotes macrophage chemotaxis. CONCLUSIONS: In colorectal carcinogenesis, pericryptal Lepr-lineage cells proliferate to generate MCAM+ CAFs that shape the tumor-promoting immune microenvironment. Preventing the expansion/differentiation of Lepr-lineage CAFs or inhibiting MCAM activity could be effective therapeutic approaches for CRC.

Chemoprevention of Oesophageal Squamous-Cell Carcinoma and Adenocarcinoma: A Multicentre Retrospective Cohort Study.

BACKGROUND: Oesophageal cancer comprises 2 different histological variants: oesophageal squamous-cell carcinoma (ESCC) and adenocarcinoma (EAC). While there are multiple therapeutic options for both types, patients with advanced or metastatic oesophageal cancer still suffer from poor prognosis. AIMS: The study aimed to examine the association between the risk of oesophageal cancer and medications and to estimate the chemopreventive effects of commonly used drugs. METHODS: A multicentre retrospective cohort study was conducted using data from 9 hospital databases of hospitalized patients between 2014 and 2019. The primary outcomes were ESCC and EAC. The association of oesophageal cancer with drug use and clinical factors was evaluated. Odds ratios (ORs) were adjusted for age, sex, Charlson comorbidity index scores, and smoking with/without gastro-oesophageal reflux disease. RESULTS: The use of proton pump inhibitors (PPIs) (adjusted OR [aOR] 0.48, p < 0.0001), aspirin (aOR 0.32, p < 0.0001), cyclooxygenase-2 inhibitor (COX2I) (aOR 0.70, p = 0.0005), steroid (aOR 0.19, p < 0.0001), statin (aOR 0.43, p < 0.0001), and metformin (aOR 0.42, p < 0.0001) was associated with a lower risk of ESCC than that in non-use. The use of aspirin (aOR 0.33, p = 0.0006) and steroids (aOR 0.54, p = 0.022) was associated with a lower risk of EAC than that in non-use. CONCLUSION: COX2Is, statins, metformin, and PPIs could help in prevention of ESCC, and aspirin and steroids may be chemopreventive for both types of oesophageal cancer.

Artificial intelligence versus expert endoscopists for diagnosis of gastric cancer in patients who have undergone upper gastrointestinal endoscopy.

AIMS: To compare endoscopy gastric cancer images diagnosis rate between artificial intelligence (AI) and expert endoscopists. PATIENTS AND METHODS: We used the retrospective data of 500 patients, including 100 with gastric cancer, matched 1:1 to diagnosis by AI or expert endoscopists. We retrospectively evaluated the noninferiority (prespecified margin 5 %) of the per-patient rate of gastric cancer diagnosis by AI and compared the per-image rate of gastric cancer diagnosis. RESULTS: Gastric cancer was diagnosed in 49 of 49 patients (100 %) in the AI group and 48 of 51 patients (94.12 %) in the expert endoscopist group (difference 5.88, 95 % confidence interval: -0.58 to 12.3). The per-image rate of gastric cancer diagnosis was higher in the AI group (99.87 %, 747 /748 images) than in the expert endoscopist group (88.17 %, 693 /786 images) (difference 11.7 %). CONCLUSIONS: Noninferiority of the rate of gastric cancer diagnosis by AI was demonstrated but superiority was not demonstrated.

Portal Vein Injection of Colorectal Cancer Organoids to Study the Liver Metastasis Stroma.

Hepatic metastasis of colorectal cancer (CRC) is a leading cause of cancer-related death. Cancer-associated fibroblasts (CAFs), a major component of the tumor microenvironment, play a crucial role in metastatic CRC progression and predict poor patient prognosis. However, there is a lack of satisfactory mouse models to study the crosstalk between metastatic cancer cells and CAFs. Here, we present a method to investigate how liver metastasis progression is regulated by the metastatic niche and possibly could be restrained by stroma-directed therapy. Portal vein injection of CRC organoids generated a desmoplastic reaction, which faithfully recapitulated the fibroblast-rich histology of human CRC liver metastases. This model was tissue-specific with a higher tumor burden in the liver when compared to an intra-splenic injection model, simplifying mouse survival analyses. By injecting luciferase-expressing tumor organoids, tumor growth kinetics could be monitored by in vivo imaging. Moreover, this preclinical model provides a useful platform to assess the efficacy of therapeutics targeting the tumor mesenchyme. We describe methods to examine whether adeno-associated virus-mediated delivery of a tumor-inhibiting stromal gene to hepatocytes could remodel the tumor microenvironment and improve mouse survival. This approach enables the development and assessment of novel therapeutic strategies to inhibit hepatic metastasis of CRC.

Cell fate analysis of zone 3 hepatocytes in liver injury and tumorigenesis.

BACKGROUND & AIMS: Liver lobules are typically subdivided into 3 metabolic zones: zones 1, 2, and 3. However, the contribution of zonal differences in hepatocytes to liver regeneration, as well as to carcinogenic susceptibility, remains unclear. METHODS: We developed a new method for sustained genetic labelling of zone 3 hepatocytes and performed fate tracing to monitor these cells in multiple mouse liver tumour models. RESULTS: We first examined changes in the zonal distribution of the Wnt target gene Axin2 over time using Axin2-Cre ERT2 ;Rosa26-Lox-Stop-Lox-tdTomato mice (Axin2;tdTomato). We found that following tamoxifen administration at 3 weeks of age, approximately one-third of total hepatocytes that correspond to zone 3 were labelled in Axin2;tdTomato mice; the tdTomato+ cell distribution closely matched that of the zone 3 marker CYP2E1. Cell fate analysis revealed that zone 3 hepatocytes maintained their own lineage but rarely proliferated beyond their liver zonation during homoeostasis; this indicated that our protocol enabled persistent genetic labelling of zone 3 hepatocytes. Using this system, we found that zone 3 hepatocytes generally had high neoplastic potential, which was promoted by constitutive activation of Wnt/ß-catenin signalling in the pericentral area. However, the frequency of zone 3 hepatocyte-derived tumours varied depending on the regeneration pattern of the liver parenchyma in response to liver injury. Notably, Axin2-expressing hepatocytes undergoing chronic liver injury significantly contributed to liver regeneration and possessed high neoplastic potential. Additionally, we revealed that the metabolic phenotypes of liver tumours were acquired during tumorigenesis, irrespective of their spatial origin. CONCLUSIONS: Hepatocytes receiving Wnt/ß-catenin signalling from their microenvironment have high neoplastic potential, and Wnt/ß-catenin signalling is a potential drug target for the prevention of hepatocellular carcinoma. LAY SUMMARY: Lineage tracing revealed that zone 3 hepatocytes residing in the pericentral niche have high neoplastic potential. Under chronic liver injury, hepatocytes receiving Wnt/ß-catenin signalling broadly exist across all hepatic zones and significantly contribute to liver tumorigenesis as well as liver regeneration. Wnt/ß-catenin signalling is a potential drug target for the prevention of hepatocellular carcinoma.

Nonsteroidal anti-inflammatory drugs prevent gastric cancer associated with the use of proton pump inhibitors after Helicobacter pylori eradication.

BACKGROUND AND AIM: Proton pump inhibitors (PPIs) are a potential cause of gastric carcinogenesis after Helicobacter pylori eradication. Thus, appropriate management including chemoprevention is required. The aim of this study was to evaluate the association between nonsteroidal anti-inflammatory drugs (NSAIDs) and the incidence of post-eradication gastric cancer in PPI users. METHODS: A multicenter retrospective cohort study was conducted. Patients who used a PPI (≥30 days) after H. pylori eradication between 2014 and 2019 were analyzed in nine hospital databases. Gastric cancer incidence was a primary outcome, and their association with NSAIDs use and clinical factors was evaluated. Hazard ratios were adjusted by age, sex, smoking, and Charlson Comorbidity Index. RESULTS: During the mean follow-up period of 2.38 years, 1.13% (31/2431) of all patients developed gastric cancer. The cumulative incidence of gastric cancer in PPI users was 0.25% at 1 year, 0.51% at 3 years, and 1.09% at 5 years in the NSAID users and 0.89% at 1 year, 2.32% at 3 years, and 3.61% at 5 years in nonusers. NSAIDs were associated with a lower gastric cancer risk (adjusted hazard ratio = 0.28, P = 0.005). No gastric cancer was observed in the cyclooxygenase-2 inhibitor users (n = 256). NSAID use with high dose and long duration was significantly associated with a lower incidence of gastric cancer. CONCLUSION: NSAIDs were associated with a 60% decrease in the gastric cancer incidence in H. pylori-eradicated PPI users, with dose and duration response effects. NSAIDs may be effective for chemoprevention against PPI-related gastric cancer.