Streptococcus anginosus promotes gastric inflammation, atrophy, and tumorigenesis in mice.

Streptococcus anginosus (S. anginosus) was enriched in the gastric mucosa of patients with gastric cancer (GC). Here, we show that S. anginosus colonized the mouse stomach and induced acute gastritis. S. anginosus infection spontaneously induced progressive chronic gastritis, parietal cell atrophy, mucinous metaplasia, and dysplasia in conventional mice, and the findings were confirmed in germ-free mice. In addition, S. anginosus accelerated GC progression in carcinogen-induced gastric tumorigenesis and YTN16 GC cell allografts. Consistently, S. anginosus disrupted gastric barrier function, promoted cell proliferation, and inhibited apoptosis. Mechanistically, we identified an S. anginosus surface protein, TMPC, that interacts with Annexin A2 (ANXA2) receptor on gastric epithelial cells. Interaction of TMPC with ANXA2 mediated attachment and colonization of S. anginosus and induced mitogen-activated protein kinase (MAPK) activation. ANXA2 knockout abrogated the induction of MAPK by S. anginosus. Thus, this study reveals S. anginosus as a pathogen that promotes gastric tumorigenesis via direct interactions with gastric epithelial cells in the TMPC-ANXA2-MAPK axis.

ALKBH5 Drives Immune Suppression Via Targeting AXIN2 to Promote Colorectal Cancer and Is a Target for Boosting Immunotherapy.

BACKGROUND & AIMS: Immune checkpoint blockade therapy benefits only a small subset of patients with colorectal cancer (CRC), and identification of CRC-intrinsic events modulating immune checkpoint blockade efficacy is an unmet need. We found that AlkB homolog 5 (ALKBH5), an RNA N6-methyladenosine eraser, drives immunosuppression and is a molecular target to boost immune checkpoint blockade therapy in CRC. METHODS: Clinical significance of ALKBH5 was evaluated in human samples (n = 205). Function of ALKBH5 was investigated in allografts, CD34+ humanized mice, and Alkbh5 knockin mice. Immunity change was determined by means of flow cytometry, immunofluorescence, and functional investigation. Methylated RNA immunoprecipitation sequencing and RNA sequencing were used to identify ALKBH5 targets. Vesicle-like nanoparticle-encapsulated ALKBH5-small interfering RNA was constructed for targeting ALKBH5 in vivo. RESULTS: High ALKBH5 expression predicts poor prognosis in CRC. ALKBH5 induced myeloid-derived suppressor cell accumulation but reduced natural killer cells and cytotoxic CD8+ T cells to induce colorectal tumorigenesis in allografts, CD34+ humanized mice, and intestine-specific Alkbh5 knockin mice. Mechanistically, AXIN2, a Wnt suppressor, was identified as a target of ALKBH5. ALKBH5 binds and demethylates AXIN2 messenger RNA, which caused its dissociation from N6-methyladenosine reader IGF2BP1 and degradation, resulting in hyperactivated Wnt/ß-catenin. Subsequently, Wnt/ß-catenin targets, including Dickkopf-related protein 1 (DKK1) were induced by ALKBH5. ALKBH5-induced DKK1 recruited myeloid-derived suppressor cells to drive immunosuppression in CRC, and this effect was abolished by anti-DKK1 in vitro and in vivo. Finally, vesicle-like nanoparticle-encapsulated ALKBH5-small interfering RNA, or anti-DKK1 potentiated anti-PD1 treatment in suppressing CRC growth by enhancing antitumor immunity. CONCLUSIONS: This study identified an ALKBH5-N6-methyladenosine-AXIN2-Wnt-DKK1 axis in CRC, which drives immune suppression to facilitate tumorigenesis. Targeting of ALKBH5 is a promising strategy for sensitizing CRC to immunotherapy.

Fibrotic immune microenvironment remodeling mediates superior anti-tumor efficacy of a nano-PD-L1 trap in hepatocellular carcinoma.

The local microenvironment where tumors develop can shape cancer progression and therapeutic outcome. Emerging evidence demonstrate that the efficacy of immune-checkpoint blockade (ICB) is undermined by fibrotic tumor microenvironment (TME). The majority of hepatocellular carcinoma (HCC) develops in liver fibrosis, in which the stromal and immune components may form a barricade against immunotherapy. Here, we report that nanodelivery of a programmed death-ligand 1 (PD-L1) trap gene exerts superior efficacy in treating fibrosis-associated HCC when compared with the conventional monoclonal antibody (mAb). In two fibrosis-associated HCC models induced by carbon tetrachloride and a high-fat, high-carbohydrate diet, the PD-L1 trap induced significantly larger tumor regression than mAb with no evidence of toxicity. Mechanistic studies revealed that PD-L1 trap, but not mAb, consistently reduced the M2 macrophage proportion in the fibrotic liver microenvironment and promoted cytotoxic interferon gamma (IFNγ)+tumor necrosis factor α (TNF-α)+CD8+T cell infiltration to the tumor. Moreover, PD-L1 trap treatment was associated with decreased tumor-infiltrating polymorphonuclear myeloid-derived suppressor cell (PMN-MDSC) accumulation, resulting in an inflamed TME with a high cytotoxic CD8+T cell/PMN-MDSC ratio conductive to anti-tumor immune response. Single-cell RNA sequencing analysis of two clinical cohorts demonstrated preferential PD-L1 expression in M2 macrophages in the fibrotic liver, thus supporting the translational potential of nano-PD-L1 trap for fibrotic HCC treatment.

Targeting PPAR-gamma counteracts tumour adaptation to immune-checkpoint blockade in hepatocellular carcinoma.

OBJECTIVE: Therapy-induced tumour microenvironment (TME) remodelling poses a major hurdle for cancer cure. As the majority of patients with hepatocellular carcinoma (HCC) exhibits primary or acquired resistance to antiprogrammed cell death (ligand)-1 (anti-PD-[L]1) therapies, we aimed to investigate the mechanisms underlying tumour adaptation to immune-checkpoint targeting. DESIGN: Two immunotherapy-resistant HCC models were generated by serial orthotopic implantation of HCC cells through anti-PD-L1-treated syngeneic, immunocompetent mice and interrogated by single-cell RNA sequencing (scRNA-seq), genomic and immune profiling. Key signalling pathway was investigated by lentiviral-mediated knockdown and pharmacological inhibition, and further verified by scRNA-seq analysis of HCC tumour biopsies from a phase II trial of pembrolizumab (NCT03419481). RESULTS: Anti-PD-L1-resistant tumours grew >10-fold larger than parental tumours in immunocompetent but not immunocompromised mice without overt genetic changes, which were accompanied by intratumoral accumulation of myeloid-derived suppressor cells (MDSC), cytotoxic to exhausted CD8+ T cell conversion and exclusion. Mechanistically, tumour cell-intrinsic upregulation of peroxisome proliferator-activated receptor-gamma (PPARγ) transcriptionally activated vascular endothelial growth factor-A (VEGF-A) production to drive MDSC expansion and CD8+ T cell dysfunction. A selective PPARγ antagonist triggered an immune suppressive-to-stimulatory TME conversion and resensitised tumours to anti-PD-L1 therapy in orthotopic and spontaneous HCC models. Importantly, 40% (6/15) of patients with HCC resistant to pembrolizumab exhibited tumorous PPARγ induction. Moreover, higher baseline PPARγ expression was associated with poorer survival of anti-PD-(L)1-treated patients in multiple cancer types. CONCLUSION: We uncover an adaptive transcriptional programme by which tumour cells evade immune-checkpoint targeting via PPARγ/VEGF-A-mediated TME immunosuppression, thus providing a strategy for counteracting immunotherapeutic resistance in HCC.

Uncovering 1058 Novel Human Enteric DNA Viruses Through Deep Long-Read Third-Generation Sequencing and Their Clinical Impact.

BACKGROUND & AIMS: Lack of viral reference genomes poses a challenge to virome study. We investigated human gut virome and its clinical implication by ultra-deep metagenomic sequencing. METHODS: We extracted sufficient viral DNA from human feces for ultra-deep PacBio sequencing (>10 µg) and Illumina sequencing (>1 µg). Upon de novo assembly and 6 stages of strict filtering, viral genomes were generated and validated in 3 cohorts of 2819 published fecal metagenomes. Diagnostic performance of assembled viruses for colorectal cancer were tested in a training cohort and 2 independent validation cohorts. Virus mapping ratio, evolutionary history, and virus status (lytic or temperate) were also examined. RESULTS: The mean amount of extracted viral DNA increased by 14-fold compared with previous protocols. We obtained PacBio long reads and Illumina short reads with 290-fold higher depth than previous studies. We assembled and validated 1178 contigs as complete viral genomes, of which 1058 were newly identified. Thirteen viral genomes (398-839 kb) that are longer than the largest bacteriophage found in humans (393 kb) were discovered. Phylogenetic tree was constructed based on Hidden Markov Models alignment scores of 4 conserved viral proteins. Incorporating our assembled genomes into the National Center for Biotechnology Information database improved the mapping ratio of published metagenomes ≤18 times. Lytic viruses (75.9% ± 12.2% of total) were predominantly present in our sample. A biomarker panel of 14 novel viruses could discriminate patients with colorectal cancer from controls with an area under the receiver operating characteristics curve of 0.87 in the training cohort, which was validated with areas under the receiver operating characteristics curve of 0.85 and 0.73 in 2 independent cohorts. CONCLUSIONS: We uncovered 1058 novel human gut viruses. These findings can contribute to clinical diagnosis, current viral reference genome, and future virome investigation.

Altered Mycobiota Signatures and Enriched Pathogenic Aspergillus rambellii Are Associated With Colorectal Cancer Based on Multicohort Fecal Metagenomic Analyses.

BACKGROUND & AIMS: The enteric mycobiota is a major component of the human gut microbiota, but its role in colorectal cancer (CRC) remains largely elusive. We conducted a meta-analysis to uncover the contribution of the fungal mycobiota to CRC. METHODS: We retrieved fecal metagenomic data sets from 7 previous publications and established an additional in-house cohort, totaling 1329 metagenomes (454 with CRC, 350 with adenoma, and 525 healthy individuals). Mycobiota composition and microbial interactions were analyzed. Candidate CRC-enriched fungal species (Aspergillus rambellii) was functionally validated in vitro and in vivo. RESULTS: Multicohort analysis revealed that the enteric mycobiota was altered in CRC. We identified fungi that were associated with patients with CRC or adenoma from multiple cohorts. Signature CRC-associated fungi included 6 enriched (A rambellii, Cordyceps sp. RAO-2017, Erysiphe pulchra, Moniliophthora perniciosa, Sphaerulina musiva, and Phytophthora capsici) and 1 depleted species (A kawachii). Co-occurrent interactions among CRC-enriched fungi became stronger in CRC compared with adenoma and healthy individuals. Moreover, we reported the transkingdom interactions between enteric fungi and bacteria in CRC progression, of which A rambellii was closely associated with CRC-enriched bacteria Fusobacterium nucleatum. A rambellii promoted CRC cell growth in vitro and tumor growth in xenograft mice. We further identified that combined fungal and bacterial biomarkers were more accurate than panels with pure bacterial species to discriminate patients with CRC from healthy individuals (the area under the curve relative change increased by 1.44%-10.60%). CONCLUSIONS: This study reveals enteric mycobiota signatures and pathogenic fungi in stages of colorectal tumorigenesis. Fecal fungi can be used, in addition to bacteria, for noninvasive diagnosis of patients with CRC.

Team-Based Approach to Reduce Malignancies in People with Diabetes and Obesity.

PURPOSE OF REVIEW: Numerous observations have indicated an increased risk of developing various types of cancers, as well as cancer-related mortality, among patients with diabetes and obesity. The purpose of this review is to outline multiple-cancer screening among these patients through a team-based approach and to present the findings of a pioneering integrated care program designed for patients with obesity with a specific emphasis on cancer prevention. RECENT FINDINGS: A community-based multi-cancer prevention program, which provides all services in one location and utilizes team-based approaches, is reported to be feasible and has the potential to enhance the uptake rate of multiple cancers screening among patients with diabetes and obesity. The team-based approach is a commonly utilized method for managing patients with diabetes, obesity, and cancer, and has been shown to be efficacious. Nevertheless, research on team-based cancer screening programs for patients with diabetes and obesity remains limited. Providing a comprehensive screening for colorectal, prostate, and breast cancer, as well as metabolic syndrome, during a single clinic visit has been proven effective and well-received by participants.

Microbial Community Heterogeneity Within Colorectal Neoplasia and its Correlation With Colorectal Carcinogenesis.

BACKGROUND & AIMS: Gut microbial dysbiosis has pivotal involvement in colorectal cancer (CRC). However, the intratumoral microbiota and its association with CRC progression remain elusive. We aimed to determine the microbial community architecture within a neoplasia (CRC or adenoma) and its contribution to colorectal carcinogenesis. METHODS: We collected 436 tissue biopsies from patients with CRC (n = 36) or adenoma (n = 32) (2-6 biopsies from a neoplasia plus 2-5 biopsies from adjacent normal tissues per individual). Microbial profiling was performed using 16S ribosomal RNA gene sequencing with subsequent investigation of microbiota diversities and heterogeneity. The correlation between microbial dysbiosis and host genetic alterations (KRAS mutation and microsatellite instability) in all neoplasia biopsies was also analyzed. RESULTS: We discovered that intra-neoplasia microbial communities are heterogeneous. Abundances of some CRC-associated pathobionts (eg, Fusobacterium, Bacteroides, Parvimonas, and Prevotella) were found to be highly varied within a single neoplasia. Correlation of such heterogeneity with CRC development revealed alterations in microbial communities involving microbes with high intra-neoplasia variation in abundance. Moreover, we found that the intra-neoplasia variation in abundance of individual microbes changed along the adenoma-carcinoma sequence. We further determined that there was a significant difference in intra-neoplasia microbiota between biopsies with and without KRAS mutation (P < .001) or microsatellite instability (P < .001), and illustrated the association of intratumoral microbial heterogeneity with genetic alteration. CONCLUSIONS: We demonstrated that intra-neoplasia microbiota is heterogeneous and correlated with colorectal carcinogenesis. Our findings provide new insights on the contribution of gut microbiota heterogeneity to CRC progression.

Enteric fungal microbiota dysbiosis and ecological alterations in colorectal cancer.

OBJECTIVES: Bacteriome and virome alterations are associated with colorectal cancer (CRC). Nevertheless, the gut fungal microbiota in CRC remains largely unexplored. We aimed to characterise enteric mycobiome in CRC. DESIGN: Faecal shotgun metagenomic sequences of 184 patients with CRC, 197 patients with adenoma and 204 control subjects from Hong Kong were analysed (discovery cohort: 73 patients with CRC and 92 control subjects; validation cohort: 111 patients with CRC, 197 patients with adenoma and 112 controls from Hong Kong). CRC-associated fungal markers and ecological changes were also validated in additional independent cohorts of 90 patients with CRC, 42 patients with adenoma and 66 control subjects of published repository sequences from Germany and France. Assignment of taxonomies was performed by exact k-mer alignment against an integrated microbial reference genome database. RESULTS: Principal component analysis revealed separate clusters for CRC and control (p<0.0001), with distinct mycobiomes in early-stage and late-stage CRC (p=0.0048). Basidiomycota:Ascomycota ratio was higher in CRC (p=0.0042), with increase in Malasseziomycetes (p<0.0001) and decrease in Saccharomycetes (p<0.0001) and Pneumocystidomycetes (p=0.0017). Abundances of 14 fungal biomarkers distinguished CRC from controls with an area under the receiver-operating characteristic curve (AUC) of 0.93 and validated AUCs of 0.82 and 0.74 in independent Chinese cohort V1 and European cohort V2, respectively. Further ecological analysis revealed higher numbers of co-occurring fungal intrakingdom and co-exclusive bacterial-fungal correlations in CRC (p<0.0001). Moreover, co-occurrence interactions between fungi and bacteria, mostly contributed by fungal Ascomycota and bacterial Proteobacteria in control, were reverted to co-exclusive interplay in CRC (p=0.00045). CONCLUSIONS: This study revealed CRC-associated mycobiome dysbiosis characterised by altered fungal composition and ecology, signifying that the gut mycobiome might play a role in CRC.

Alterations in Enteric Virome Are Associated With Colorectal Cancer and Survival Outcomes.

BACKGROUND & AIMS: Patients with colorectal cancer (CRC) have a different gut microbiome signature than individuals without CRC. Little is known about the viral component of CRC-associated microbiome. We aimed to identify and validate viral taxonomic markers of CRC that might be used in detection of the disease or predicting outcome. METHODS: We performed shotgun metagenomic analyses of viromes of fecal samples from 74 patients with CRC (cases) and 92 individuals without CRC (controls) in Hong Kong (discovery cohort). Viral sequences were classified by taxonomic alignment against an integrated microbial reference genome database. Viral markers associated with CRC were validated using fecal samples from 3 separate cohorts: 111 patients with CRC and 112 controls in Hong Kong, 46 patients with CRC and 63 controls in Austria, and 91 patients with CRC and 66 controls in France and Germany. Using abundance profiles of CRC-associated virome genera, we constructed random survival forest models to identify those associated with patient survival times. RESULTS: The diversity of the gut bacteriophage community was significantly increased in patients with CRC compared with controls. Twenty-two viral taxa discriminated cases from controls with an area under the receiver operating characteristic curve of 0.802 in the discovery cohort. The viral markers were validated in 3 cohorts, with area under the receiver operating characteristic curves of 0.763, 0.736, and 0.715, respectively. Clinical subgroup analysis showed that dysbiosis of the gut virome was associated with early- and late-stage CRC. A combination of 4 taxonomic markers associated with reduced survival of patients with CRC (log-rank test, P = 8.1 × 10-6) independently of tumor stage, lymph node metastases, or clinical parameters. We found altered interactions between bacteriophages and oral bacterial commensals in fecal samples from patients with CRC compared with controls. CONCLUSIONS: In a metagenomic analysis of fecal samples from patients and controls, we identified virome signatures associated with CRC. These data might be used to develop tools to identify individuals with CRC or predict outcomes.

Gastrointestinal disease burden and mortality: A public hospital-based study from 2005 to 2014.

BACKGROUND AND AIM: Gastrointestinal (GI) diseases account for substantial morbidity, mortality, and health care utilization. This public hospital-based study assessed the incidence and time trend of hospitalization and mortality of major GI diseases over one decade. METHODS: We conducted an observational study using population-wide database managed by the Hong Kong Hospital Authority with a principal diagnosis of GI diseases defined by International Classification of Disease, 9th Revision, Clinical Modification coding. We measured age-standardized incidence of hospitalization, emergency admissions, multiple admissions, and in-hospital mortality from 2005 to 2014 using Poisson regression. RESULTS: The annual incidence of hospitalization for GI diseases increased from 4713 to 5241 per 100 000 discharges (incidence rate ratio [IRR] = 1.004; 95% confidence interval [CI]: 1.003-1.005). GI infections and cancers showed the highest rates of hospitalization in 2014. Hospitalization for GI cancers (IRR = 1.014; 95% CI: 1.013-1.016) and non-infectious enterocolitis (IRR = 1.058; 95% CI: 1.055-1.061) increased, whereas peptic ulcer disease has decreased. Hospitalization for Crohn's disease showed the most significant rise (126%). Annual incidence of hospitalization for Clostridium difficile infections increased by fivefold (IRR = 1.221; 95% CI: 1.178-1.266), while a 66% reduction was observed for peptic ulcer bleeding (IRR = 0.894; 95% CI: 0.889-0.899). GI cancers had the highest in-hospital mortality rate in 2014, especially colorectal cancer and gastric cancer. CONCLUSIONS: This study showed an increased hospitalization burden of GI cancers and Crohn's disease, and a reduction in overall mortality for GI diseases. These data provide insight into epidemiological changes of GI diseases in the 21st century and implications for hospital burden and need of resource re-allocation.

Association between investigator-measured body-mass index and colorectal adenoma: a systematic review and meta-analysis of 168,201 subjects.

The objective of this meta-analysis is to evaluate the odds of colorectal adenoma (CRA) in colorectal cancer screening participants with different body mass index (BMI) levels, and examine if this association was different according to gender and ethnicity. The EMBASE and MEDLINE were searched to enroll high quality observational studies that examined the association between investigator-measured BMI and colonoscopy-diagnosed CRA. Data were independently extracted by two reviewers. A random-effects meta-analysis was conducted to estimate the summary odds ratio (SOR) for the association between BMI and CRA. The Cochran's Q statistic and I2 analyses were used to assess the heterogeneity. A total of 17 studies (168,201 subjects) were included. When compared with subjects having BMI < 25, individuals with BMI 25-30 had significantly higher risk of CRA (SOR 1.44, 95% CI 1.30-1.61; I2 = 43.0%). Subjects with BMI ≥ 30 had similarly higher risk of CRA (SOR 1.42, 95% CI 1.24-1.63; I2 = 18.5%). The heterogeneity was mild to moderate among studies. The associations were significantly higher than estimates by previous meta-analyses. There was no publication bias detected (Egger's regression test, p = 0.584). Subgroup analysis showed that the magnitude of association was significantly higher in female than male subjects (SOR 1.43, 95% CI 1.30-1.58 vs. SOR 1.16, 95% CI 1.07-1.24; different among different ethnic groups (SOR 1.72, 1.44 and 0.88 in White, Asians and Africans, respectively) being insignificant in Africans; and no difference exists among different study designs. In summary, the risk conferred by BMI for CRA was significantly higher than that reported previously. These findings bear implications in CRA risk estimation.

Metagenomic analysis of faecal microbiome as a tool towards targeted non-invasive biomarkers for colorectal cancer.

OBJECTIVE: To evaluate the potential for diagnosing colorectal cancer (CRC) from faecal metagenomes. DESIGN: We performed metagenome-wide association studies on faecal samples from 74 patients with CRC and 54 controls from China, and validated the results in 16 patients and 24 controls from Denmark. We further validated the biomarkers in two published cohorts from France and Austria. Finally, we employed targeted quantitative PCR (qPCR) assays to evaluate diagnostic potential of selected biomarkers in an independent Chinese cohort of 47 patients and 109 controls. RESULTS: Besides confirming known associations of Fusobacterium nucleatum and Peptostreptococcus stomatis with CRC, we found significant associations with several species, including Parvimonas micra and Solobacterium moorei. We identified 20 microbial gene markers that differentiated CRC and control microbiomes, and validated 4 markers in the Danish cohort. In the French and Austrian cohorts, these four genes distinguished CRC metagenomes from controls with areas under the receiver-operating curve (AUC) of 0.72 and 0.77, respectively. qPCR measurements of two of these genes accurately classified patients with CRC in the independent Chinese cohort with AUC=0.84 and OR of 23. These genes were enriched in early-stage (I-II) patient microbiomes, highlighting the potential for using faecal metagenomic biomarkers for early diagnosis of CRC. CONCLUSIONS: We present the first metagenomic profiling study of CRC faecal microbiomes to discover and validate microbial biomarkers in ethnically different cohorts, and to independently validate selected biomarkers using an affordable clinically relevant technology. Our study thus takes a step further towards affordable non-invasive early diagnostic biomarkers for CRC from faecal samples.

High-dose omeprazole infusion compared with scheduled second-look endoscopy for prevention of peptic ulcer rebleeding: a randomized controlled trial.

BACKGROUND AND STUDY AIM: Previous studies have shown that both scheduled second-look endoscopy and high-dose continuous omeprazole infusion are effective in preventing peptic ulcer rebleeding. The aim of this noninferiority trial was to compare the efficacy of these two strategies for the prevention of rebleeding following primary endoscopic hemostasis. PATIENTS AND METHODS: Consecutive patients who received endoscopic treatment for bleeding peptic ulcers (actively bleeding, with nonbleeding visible vessels) were randomized to two treatment groups following hemostasis. One group (second-look endoscopy group) received the proton pump inhibitor (PPI) omeprazole as an intravenous bolus every 12 hours for 72 hours and a second endoscopy within 16 - 24 hours with retreatment for persistent stigmata of bleeding. The other group (PPI infusion group) received continuous high-dose omeprazole infusion for 72 hours. Patients who developed rebleeding underwent surgery if repeat endoscopic therapy failed. The primary outcome was the rebleeding rate within 30 days after initial hemostasis. The margin for noninferiority was set at 5 %. RESULTS: A total of 153 patients were randomized to the PPI infusion group and 152 to the second-look endoscopy group. Rebleeding occurred within 30 days in 10 patients (6.5 %) in the PPI infusion group and in 12 patients (7.9 %) in the second-look endoscopy group (P = 0.646). Surgery was required for rebleeding in six patients from the PPI infusion group and three patients in the second-look endoscopy group (P = 0.32). Intensive care unit stay, transfusion requirements, and mortality were not different between the groups. Patients in the second-look endoscopy group were discharged 1 day earlier than those in the PPI infusion group (P < 0.001). CONCLUSIONS: After endoscopic hemostasis, high-dose PPI infusion was not inferior to second-look endoscopy with bolus PPI in preventing peptic ulcer rebleeding. TRIAL REGISTRATION: ClinicalTrials.gov (NCT: 00164931).

Recognition of goblet cells upon endocytoscopy indicates the presence of gastric intestinal metaplasia.

BACKGROUND: Gastric intestinal metaplasia (IM) is considered precancerous and is difficult to differentiate upon endoscopy. Endocytoscopy enables observation at a cellular level for focused biopsy. The present study examined the use of endocytoscopy for recognition of gastric IM. PATIENTS AND METHODS: Patients with a history of gastric IM were recruited. We first carried out narrow band imaging (NBI) endoscopy to look for suspicious areas of gastric IM. A prototype endocytoscope with a magnification of 450× was used to re-examine these areas. Areas examined were biopsied for histological comparison. Presence of goblet cells was considered as representative of IM upon endocytoscopy. RESULTS: Twenty patients were recruited with NBI demonstrating 102 suspicious lesions of gastric IM. Mean age of patients was 53.9 ± 7.6 years. Upon histology, 72 biopsies were confirmed as gastric IM, 15 showed IM and low-grade dysplasia, whereas 15were diagnosed as chronic gastritis. Endocytoscopy image quality was significantly better for areas of IM as compared to gastritis (P < 0.05; OR 21.7 [95% CI 4.5-105.9]). The presence of goblet cells upon endocytoscopy achieved a diagnostic accuracy of 0.86 for gastric IM. Receiver operator characteristics curve achieved an area under curve of 0.8 with the presence of goblet cells under endocytoscopy as compared to 0.64 for NBI alone. CONCLUSIONS: Presence of goblet cells upon endocytoscopy indicates a diagnosis of gastric IM. Image quality of endocytoscopy, however, is suboptimal. Further developments in endocytoscopy should focus on image quality and staining methods to enhance differentiation between IM, dysplasia and early gastric cancer.

Personalized drug screening using patient-derived organoid and its clinical relevance in gastric cancer.

The efficacy of chemotherapy varies significantly among patients with gastric cancer (GC), and there is currently no effective strategy to predict chemotherapeutic outcomes. In this study, we successfully establish 57 GC patient-derived organoids (PDOs) from 73 patients with GC (78%). These organoids retain histological characteristics of their corresponding primary GC tissues. GC PDOs show varied responses to different chemotherapeutics. Through RNA sequencing, the upregulation of tumor suppression genes/pathways is identified in 5-fluorouracil (FU)- or oxaliplatin-sensitive organoids, whereas genes/pathways associated with proliferation and invasion are enriched in chemotherapy-resistant organoids. Gene expression biomarker panels, which could distinguish sensitive and resistant patients to 5-FU and oxaliplatin (area under the dose-response curve [AUC] >0.8), are identified. Moreover, the drug-response results in PDOs are validated in patient-derived organoids-based xenograft (PDOX) mice and are consistent with the actual clinical response in 91.7% (11/12) of patients with GC. Assessing chemosensitivity in PDOs can be utilized as a valuable tool for screening chemotherapeutic drugs in patients with GC.

Generative artificial intelligence and ethical considerations in health care: a scoping review and ethics checklist.

The widespread use of Chat Generative Pre-trained Transformer (known as ChatGPT) and other emerging technology that is powered by generative artificial intelligence (GenAI) has drawn attention to the potential ethical issues they can cause, especially in high-stakes applications such as health care, but ethical discussions have not yet been translated into operationalisable solutions. Furthermore, ongoing ethical discussions often neglect other types of GenAI that have been used to synthesise data (eg, images) for research and practical purposes, which resolve some ethical issues and expose others. We did a scoping review of the ethical discussions on GenAI in health care to comprehensively analyse gaps in the research. To reduce the gaps, we have developed a checklist for comprehensive assessment and evaluation of ethical discussions in GenAI research. The checklist can be integrated into peer review and publication systems to enhance GenAI research and might be useful for ethics-related disclosures for GenAI-powered products and health-care applications of such products and beyond.