Spatial and single-cell colocalisation analysis reveals MDK-mediated immunosuppressive environment with regulatory T cells in colorectal carcinogenesis

BACKGROUND

Cell-cell interaction factors that facilitate the progression of adenoma to sporadic colorectal cancer (CRC) remain unclear, thereby hindering patient survival.

METHODS

We performed spatial transcriptomics on five early CRC cases, which included adenoma and carcinoma, and one advanced CRC. To elucidate cell-cell interactions within the tumour microenvironment (TME), we investigated the colocalisation network at single-cell resolution using a deep generative model for colocalisation analysis, combined with a single-cell transcriptome, and assessed the clinical significance in CRC patients.

FINDINGS

CRC cells colocalised with regulatory T cells (Tregs) at the adenoma-carcinoma interface. At early-stage carcinogenesis, cell-cell interaction inference between colocalised adenoma and cancer epithelial cells and Tregs based on the spatial distribution of single cells highlighted midkine (MDK) as a prominent signalling molecule sent from tumour epithelial cells to Tregs. Interaction between MDK-high CRC cells and SPP1+ macrophages and stromal cells proved to be the mechanism underlying immunosuppression in the TME. Additionally, we identified syndecan4 (SDC4) as a receptor for MDK associated with Treg colocalisation. Finally, clinical analysis using CRC datasets indicated that increased MDK/SDC4 levels correlated with poor overall survival in CRC patients.

INTERPRETATION

MDK is involved in the immune tolerance shown by Tregs to tumour growth. MDK-mediated formation of the TME could be a potential target for early diagnosis and treatment of CRC.

FUNDING

Japan Society for the Promotion of Science (JSPS) Grant-in-Aid for Science Research; OITA Cancer Research Foundation; AMED under Grant Number; Japan Science and Technology Agency (JST); Takeda Science Foundation; The Princess Takamatsu Cancer Research Fund.

Hepatic extracellular ATP/adenosine dynamics in zebrafish models of alcoholic and metabolic steatotic liver disease

Steatotic liver disease (SLD) is a burgeoning health problem predominantly associated with excessive alcohol consumption, which causes alcohol-related liver disease (ALD), and high caloric intake, which results in metabolic dysfunction-associated SLD (MASLD). The pathogenesis of ALD and MASLD, which can progress from steatohepatitis to more severe conditions such as liver fibrosis, cirrhosis, and hepatocellular carcinoma, is complicated by several factors. Recently, extracellular ATP and adenosine (Ado), as damage-associated molecular patterns, were reported to promote inflammation and liver fibrosis, contributing to SLD pathogenesis. Here, we explored the in vivo dynamics of hepatic extracellular ATP and Ado during the progression of steatohepatitis using a genetically encoded GPCR-activation-based sensor (GRAB) in zebrafish models. We established hepatocyte-specific GRABATP and GRABAdo in zebrafish and investigated the changes in in vivo hepatic extracellular ATP and Ado levels under ALD or MASLD conditions. Disease-specific changes in hepatocyte extracellular ATP and Ado levels were observed, clearly indicating a correlation between hepatocyte extracellular ATP/Ado dynamics and disease progression. Furthermore, clodronate, a vesicular nucleotide transporter inhibitor, alleviated the MASLD phenotype by reducing the hepatic extracellular ATP and Ado content. These findings provide deep insights into extracellular ATP/Ado dynamics in disease progression, suggesting therapeutic potential for ALD and MASLD.

Multicenter study of invasive gastric cancer detected after 10 years of Helicobacter pylori eradication in Japan: Clinical, endoscopic, and histopathologic characteristics

Objectives

Gastric cancer can be diagnosed even in patients long after Helicobacter pylori eradication. Most cases involve intramucosal lesions; however, some are invasive and require surgery. To clarify appropriate long-term surveillance methods, this study compared invasive gastric cancer diagnosed ≥10 and <10 years after eradication.

Methods

This retrospective multicenter study included 14 institutions. We included 377 patients with gastric cancer with submucosal or deep invasion after surgical or endoscopic resection. Ordered logistic regression analysis was used to explore the factors contributing to the pathological stage and histological type.

Results

Invasive gastric cancer was detected in 84 patients (Group L) and 293 patients (Group S) ≥10 and <10 years after H. pylori eradication, respectively. Endoscopic mucosal atrophy at the time of cancer detection was similar in both groups; 50% of the patients had severe atrophy. Annual endoscopy correlated with early pathological stage (odds ratio [OR] 0.28, 95% confidence interval [CI] 0.14-0.54, p < 0.001). Group L exhibited an independent correlation with the advanced pathological stage (OR 2.27, 95% CI 1.06-4.88, p = 0.035) and the undifferentiated type (OR 2.12, 95% CI 1.16-3.90, p = 0.015). The pure differentiated type and early pathological stage significantly (p = 0.001) correlated with severe mucosal atrophy in Group S but not in Group L.

Conclusions

Invasive cancers diagnosed ≥10 years after H. pylori eradication were likely to be more malignant in histological type and pathological stage. Gastric cancer surveillance should continue regardless of endoscopic atrophy, particularly ≥10 years after eradication.

Endoscopic Ultrasound Can Differentiate High-Grade Pancreatic Intraepithelial Neoplasia, Small Pancreatic Ductal Adenocarcinoma, and Benign Stenosis

Background/Aims

High-grade pancreatic intraepithelial neoplasia and invasive pancreatic ductal adenocarcinoma ≤10 mm are targets for early detection of pancreatic cancer. However, their imaging characteristics are unknown. We aimed to identify endoscopic ultrasound findings for the detection of these lesions.

Methods

Patients diagnosed with high-grade pancreatic intraepithelial neoplasia (n=29), pancreatic ductal adenocarcinoma ≤10 mm (n=11) (who underwent surgical resection), or benign main pancreatic duct stenosis (n=20) between January 2014 and January 2021 were retrospectively included. Six features differentiating these lesions were examined by endoscopic ultrasonography: main pancreatic duct stenosis, upstream main pancreatic duct dilation, hypoechoic areas surrounding the main pancreatic duct irregularities (mottled areas without demarcation or round areas with demarcation), branch duct dilation, prominent lobular segmentation, and atrophy. Interobserver agreement was assessed by two independent observers.

Results

Hypoechoic areas surrounding the main pancreatic duct irregularities were observed more frequently in high-grade pancreatic intraepithelial neoplasia (82.8%) and pancreatic ductal adenocarcinoma ≤10 mm (90.9%) than in benign stenosis (15.0%) (p<0.001). High-grade pancreatic intraepithelial neoplasia exhibited mottled hypoechoic areas more frequently (79.3% vs 18.9%, p<0.001), and round hypoechoic areas less frequently (3.4% vs 72.7%, p<0.001), than pancreatic ductal adenocarcinoma ≤10 mm. The sensitivity and specificity of hypoechoic areas for differentiating high-grade pancreatic intraepithelial neoplasia, pancreatic ductal adenocarcinoma ≤10 mm, and benign stenosis were both 85.0%, with moderate interobserver agreement.

Conclusions

The hypoechoic areas surrounding main pancreatic duct irregularities on endoscopic ultrasound may differentiate between high-grade pancreatic intraepithelial neoplasia, pancreatic ductal adenocarcinoma ≤10 mm, and benign stenosis (Trial Registration: UMIN Clinical Trials Registry (UMIN000044789).

Tapeworm Infection Diagnosed after Campylobacter jejuni-induced Enteritis

A 35-year-old man with fever and diarrhea visited our hospital because of white string-like fecal excretion. Based on a morphological examination of the excreted object, a Diphyllobothrium infection was suspected. Additionally, Gram staining of a fecal sample revealed Campylobacter infection. After the intraduodenal administration of meglumine/diatrizoate sodium, the tapeworm was excreted. A polymerase chain reaction-based DNA sequence analysis demonstrated that the tapeworm excreted in this case was Diphyllobothrium nihonkaiensis. This report presents a rare case of coinfection with Diphyllobothrium nihonkaiensis and Campylobacter jejuni. Therefore, it is important to consider the coexistence of other intestinal infections when diagnosing parasitic infections in patients with fever.

Characterization of residual cancer by comparison of a pair of organoids established from a patient with esophageal squamous cell carcinoma before and after neoadjuvant chemotherapy

Neoadjuvant chemotherapy (NAC) followed by surgery is a standard approach for management of locally advanced esophageal squamous cell carcinoma (ESCC). Patients who do not respond well to NAC have a poor prognosis. Despite extensive research, the mechanisms of chemoresistance in ESCC remain largely unknown. Here, we established paired tumor organoids-designated as PreNAC-O and PostNAC-O-from one ESCC patient before and after NAC, respectively. Although the two organoids did not exhibit significant differences in proliferation, morphology or drug sensitivity in vitro, the tumorigenicity of PostNAC-O in vivo was significantly higher than that of PreNAC-O. Xenografts from PreNAC-O tended to exhibit keratinization, while those from PostNAC-O displayed conspicuous necrotic areas. The tumorigenicity of PostNAC-O xenografts during the chemotherapy was comparable to that of PreNAC-O without treatment. Furthermore, the gene expression profiles of the xenografts suggested that expression of genes involved in the EMT and/or hypoxia response might be related to the tumorigenicity of PostNAC-O. Our data suggested that the tumorigenicity of residual cancer had been enhanced, outweighing the effects of chemotherapy, rather than being attributable to intrinsic chemoresistance. Further studies are required to clarify the extent to which residual cancers share a common mechanism similar to that revealed here.

True diagnostic ability of EUS-guided fine-needle aspiration/biopsy sampling for small pancreatic lesions ≤10 mm and salvage diagnosis by pancreatic juice cytology: a multicenter study

BACKGROUND AND AIMS

The diagnostic performance of EUS-guided fine-needle aspiration/biopsy sampling (EUS-FNAB) for pancreatic ductal adenocarcinoma (PDAC) ≤10 mm in diameter is relatively low. Pancreatic juice cytology (PJC) has gained attention because of its high sensitivity for small PDACs. We aimed to clarify the diagnostic ability of EUS-FNAB and the salvage ability of PJC for PDAC ≤10 mm.

METHODS

Data obtained from attempted EUS-FNAB for patients with EUS-confirmed pancreatic tumors ≤10 mm (excluding pancreatic metastases/malignant lymphomas) were retrospectively analyzed. Patients who experienced technical failure or had a negative EUS-FNAB result and had a strong likelihood of PDAC based on imaging characteristics underwent PJC. PDAC was diagnosed using resected histologic specimens, EUS-FNAB-positive tumor growth on the imaging examination, or additional EUS-FNAB-positive results after increase in tumor size. The primary endpoint was the diagnostic ability of EUS-FNAB for PDAC ≤10 mm. The salvage ability of PJC was also assessed.

RESULTS

Overall, 86 of 271 patients with pancreatic tumors ≤10 mm who underwent attempted EUS-FNAB were diagnosed with PDAC. The technical success rate, sensitivity, specificity, and accuracy of EUS-FNAB for PDAC ≤10 mm were 80.8%, 82.3%, 94.9%, and 91.3%, respectively. Among the 35 PDAC patients who experienced technical failure or false-negative results of EUS-FNAB, 26 (74.3%) were correctly diagnosed using salvage PJC.

CONCLUSIONS

The true success rate and sensitivity of EUS-FNAB for PDAC ≤10 mm were relatively low. When EUS-FNAB for a pancreatic lesion ≤10 mm strongly suspected to be PDAC is unsuccessful or yields a negative result, PJC is recommended. (Clinical trial registration number: UMIN000049965.).

Antimicrobial-resistant Helicobacter pylori in Japan: Report of nationwide surveillance for 2018-2020

BACKGROUND

Antimicrobial therapy is necessary to eradicate Helicobacter pylori infection. The emergence of antimicrobial-resistant bacteria poses a threat to continued treatment with antimicrobial agents. For those who prescribe antimicrobial therapy, it is necessary to constantly monitor the emergence of antimicrobial-resistant bacteria.

METHOD

H. pylori clinical isolates were collected in Japan from August 2018 to December 2020 for antimicrobial susceptibility testing. The agar dilution method was used for the determination of the minimum inhibitory concentration (MIC) of clarithromycin (CLR), amoxicillin (AMX), metronidazole (MNZ), and sitafloxacin (STX).

RESULTS

MICs for 938 H. pylori isolates were examined. The primary resistance rates of H. pylori clinical isolates for CLR, AMX, MNZ, and STX in Japan were 35.5%, 2.7%, 4.2%, and 27.6%, respectively. The primary resistance rates for CLR, AMX, and MNZ were significantly higher than those of the 2002-2005 isolates. The resistance rate for CLR was significantly higher in females (males: 30.7%, females: 41.5%, p < 0.001) and higher in the ≤29 years age group (54.8%) than in the other age groups, although there were no significant differences (p = 0.104). The MNZ resistance rate was significantly higher in the ≤29 years age group than in the other age groups (p = 0.004). The resistance rate for STX increased with age, but a significant difference was only seen between the 30-49 years age group and the ≥70 years age group (p < 0.001), and the resistance rate was significantly higher in strains isolated in the Kyushu region than in the other regions (p < 0.001).

CONCLUSIONS

The primary resistance rates for CLR, AMX, and MNZ of H. pylori clinical isolates in Japan were higher than those of the 2002-2005 isolates. Continuous surveillance is needed to monitor the trends in antimicrobial-resistant H. pylori.

Clinical significance of colonoscopy before laparoscopic bariatric/metabolic surgery in Japanese patients

PURPOSE

Obesity is known to be associated with colorectal adenoma (CRA) and colorectal cancer (CRC); yet colonoscopy is not considered an essential preoperative evaluation before bariatric/metabolic surgery. The aim of this study was to clarify the clinical significance of preoperative colonoscopy for obese Japanese patients.

METHODS

The subjects of this retrospective study were 114 patients who underwent screening colonoscopy before bariatric/metabolic surgery. Multivariate analyses were performed to evaluate the independent predictors of CRA/CRC among the characteristics identified as significant or nearly significant by univariate analyses.

RESULTS

Colonoscopy revealed abnormal findings indicating the need for biopsy or polypectomy in 20 of the 114 patients (17.5%), and CRA was diagnosed in 13 patients (11.4%). Three patients (2.6%), who were all ≥ 56 years old, had a CRA ≥ 10 mm in diameter. The multivariate analysis showed that older age and male sex were significant predictors of CRA/CRC, which was identified in 46.2% of the male patients aged ≥ 46 years.

CONCLUSION

Our findings suggest that older age and male sex may be risk factors for CRA/CRC in obese Japanese candidates for bariatric/metabolic surgery; thus, preoperative colonoscopy should be considered for these high-risk patients.

Background factors of idiopathic peptic ulcers and optimal treatment methods: a multicenter retrospective Japanese study

This study investigated the trends in idiopathic peptic ulcers, examined the characteristics of refractory idiopathic peptic ulcer, and identified the optimal treatment. The characteristics of 309 patients with idiopathic peptic ulcer were examined. We allocated idiopathic peptic ulcers that did not heal after 8 weeks' treatment (6 weeks for duodenal ulcers) to the refractory group and those that healed within this period to the healed group. The typical risk factors for idiopathic peptic ulcer (atherosclerosis-related underlying disease or liver cirrhosis complications) were absent in 46.6% of patients. Absence of gastric mucosal atrophy (refractory group: 51.4%, healed group: 28.4%; p = 0.016), and gastric fundic gland polyps (refractory group: 17.6%, healed group: 5.9%; p = 0.045) were significantly more common in the refractory group compared to the healed group. A history of H. pylori eradication (refractory group: 85.3%, healed group: 66.0%; p = 0.016), previous H. pylori infection (i.e., gastric mucosal atrophy or history of H. pylori eradication) (refractory group: 48.5%, healed group: 80.0%; p = 0.001), and potassium-competitive acid blocker treatment (refractory group: 28.6%, healed group, 64.1%; p = 0.001) were significantly more frequent in the healed group compared to the refractory group. Thus, acid hypersecretion may be a major factor underlying the refractoriness of idiopathic peptic ulcer.

A case of hepatosplenic cat scratch disease with hemophagocytic lymphohistiocytosis

Cat scratch disease (CSD) is associated with Bartonella henselae (B. henselae) infection caused by cat scratches or bites. It typically presents with lymphadenitis and fever. However, there are atypical cases such as hepatosplenic CSD, which presents with specific lesions in the liver and spleen. Hemophagocytic lymphohistiocytosis (HLH) is a rare and severe multisystem disorder triggered by infections, cancers, or autoimmune diseases. We experienced a rare case of hepatosplenic CSD with HLH in a non-immunocompromised adult. A 78-year-old woman complained of fever and fatigue. Laboratory tests revealed anemia and liver dysfunction; abdominal contrast-enhanced computed tomography (CT) revealed splenomegaly and nodular hypodense areas in the spleen. In addition, the levels of ferritin and serum soluble IL-2R were markedly elevated, so clinical diagnosis of HLH was made. Positron emission tomography/CT revealed diffuse fluorodeoxyglucose uptake in the liver and spleen suggesting malignant lymphoma, while the pathological findings from liver biopsy suggested infectious diseases. Although she had no cat bites and scratches, she had many cats; therefore, serum B. henselae antibody titers were measured. The B. henselae IgG and IgM titer were 1:128 and 1:20; thus, she was diagnosed with hepatosplenic CSD. Patients with hepatosplenic nodular lesions and contact with cats should be considered for this disease.

Omics-Based Mathematical Modeling Unveils Pathogenesis of Periodontitis in an Experimental Murine Model

Periodontitis is a multifactorial disease that progresses via dynamic interaction between bacterial and host-derived genetic factors. The recent trend of omics analyses has discovered many periodontitis-related risk factors. However, how much the individual factor affects the pathogenesis of periodontitis is still unknown. This article aims to identify multiple key factors related to the pathogenesis of periodontitis and quantitatively predict the influence of each factor on alveolar bone resorption by omics analysis and mathematical modeling. First, we induced periodontitis in mice (n = 3 or 4 at each time point) by tooth ligation. Next, we assessed alveolar bone resorption by micro-computed tomography, alterations in the gene expression by RNA sequencing, and the microbiome of the gingivae by 16S ribosomal RNA sequencing during disease pathogenesis. Omics data analysis identified key players (bacteria and molecules) involved in the pathogenesis of periodontitis. We then constructed a mathematical model of the pathogenesis of periodontitis by employing ordinary differential equations that described the dynamic regulatory interplay between the key players and predicted the alveolar bone integrity as output. Finally, we estimated the model parameters using our dynamic experimental data and validated the model prediction of influence on alveolar bone resorption by in vivo experiments. The model predictions and experimental results revealed that monocyte recruitment induced by bacteria-mediated Toll-like receptor activation was the principal reaction regulating alveolar bone resorption in a periodontitis condition. On the other hand, osteoblast-mediated osteoclast differentiation had less impact on bone integrity in a periodontitis condition.

Strategy Comparison of Endoscopic Ultrasound-Guided Gallbladder Drainage to Percutaneous Transhepatic Gallbladder Drainage, Following Failed Emergent Endoscopic Transpapillary Gallbladder Drainage

Endoscopic transpapillary gallbladder drainage (ETGBD) is recommended for patients with acute cholecystitis at high risk for surgery/percutaneous transhepatic gallbladder drainage (PTGBD). Endoscopic ultrasound-guided gallbladder drainage (EUS-GBD) has higher success and mortality rates than ETGBD. Optimal endoscopic drainage remains controversial. Patients with moderate/severe acute cholecystitis and high risk for surgery/PTGBD who underwent ETGBD were enrolled. In the new-ETGBD (N-ETGBD)/traditional-ETGBD (T-ETGBD) strategy, patients in whom the initial ETGBD failed underwent rescue-EUS-GBD in the same endoscopic session/rescue-PTGBD, respectively. Therapeutic outcomes were compared. Patients who could not undergo rescue-EUS-GBD/PTGBD owing to poor general conditions received conservative treatment. Technical success was defined as successful ETGBD or successful rescue-EUS-GBD/PTGBD. Forty-one/forty patients were enrolled in the N-ETGBD/T-ETGBD groups, respectively. The N-ETGBD group had a higher, though non-significant, technical success rate compared to the T-ETGBD group (97.6 vs. 90.0%, p = 0.157). The endoscopic technical success rate was significantly higher in the N-ETGBD than in the T-ETGBD group (97.6 vs. 82.5%, p = 0.023). The clinical success/adverse event rates were similar between both groups. The hospitalization duration was significantly shorter in the N-ETGBD than in the T-ETGBD group (6.6 ± 3.9 vs. 10.1 ± 6.4 days, p < 0.001). ETGBD with EUS-GBD as a rescue backup may be an ideal hybrid drainage for emergency endoscopic gallbladder drainage in high-risk surgical patients.

Overexpression of VSNL1 Enhances Cell Proliferation in Colorectal Carcinogenesis

INTRODUCTION

We have previously reported that overexpression of visinin-like protein 1 (VSNL1) is frequently observed in advanced colorectal adenocarcinomas and correlates with poorer prognosis. In this study, we determined the levels of VSNL1 expression in the earlier stages of colorectal tumors including adenomas and adenocarcinomas, and attempted to clarify the functional significance of VSNL1 overexpression in colorectal carcinogenesis.

METHODS

Levels of VSNL expression in colorectal tumor tissues were analyzed using immunohistochemistry. The effects of VSNL1 downregulation and overexpression on cell proliferation, resistance to apoptosis, and invasiveness were determined using two VSNL1-overexpressing colorectal cancer cell lines, CW-2 and HCT-116 and VSNL1 inducibly expressing SNU-C5, respectively. Gene expression signatures in VSNL1-downregulated CW-2 and HCT-116 were identified using transcriptome and gene set enrichment analyses.

RESULTS

VSNL1 expression was restricted to only a few crypt cells in the non-tumorous epithelium, whereas it became enhanced in adenomas and adenocarcinomas with the progression of tumorigenesis. Downregulation of VSNL1 in CW-2 and HCT-116 cells suppressed their proliferation through induction of apoptosis. Conversely, overexpression of VSNL1 in SNU-C5 cells enhanced resistance to anoikis. Transcriptome and gene set enrichment analyses revealed that downregulation of VSNL1 altered the expression level of the apoptosis-related gene set in CW-2 and HCT-116 cells.

CONCLUSION

VSNL1 plays a role in both the development and progression of colorectal tumors by enhancing cell viability.

Usefulness of AI-Equipped Endoscopy for Detecting Colorectal Adenoma during Colonoscopy Screening: Confirm That Colon Neoplasm Finely Can Be Identified by AI without Overlooking Study (Confidential Study)

In the present prospective case series study, we investigated the lesion-detection ability of an AI-equipped colonoscopy as an addition to colonoscopy (CS) screening. Participants were 100 patients aged ≥20 years who had not undergone CS at the study site in the last 3 years and passed the exclusion criteria. CS procedures were conducted using conventional white light imaging and computer-aided detection (CADe). Adenoma detection rate (ADR; number of individuals with at least one adenoma detected) was compared between the conventional group and the CADe group. Of the 170 lesions identified, the ADR of the CADe group was significantly higher than the ADR of the conventional group (69% vs. 61%, p = 0.008). For the expert endoscopists, although ADR did not differ significantly, the mean number of detected adenomas per procedure (MAP) was significantly higher in the CADe group than in the conventional group (1.7 vs. 1.45, p = 0.034). For non-expert endoscopists, ADR and MAP were significantly higher in the CADe group than in the conventional group (ADR 69.5% vs. 56.6%, p = 0.016; MAP 1.66 vs. 1.11, p < 0.001). These results indicate that the CADe function in CS screening has a positive effect on adenoma detection, especially for non-experts.

The methylation level of a single cancer risk marker gene reflects methylation burden in gastric mucosa

BACKGROUND

Gastric cancer risk can be accurately predicted by measuring the methylation level of a single marker gene in gastric mucosa. However, the mechanism is still uncertain. We hypothesized that the methylation level measured reflects methylation alterations in the entire genome (methylation burden), induced by Helicobacter pylori (H. pylori) infection, and thus cancer risk.

METHODS

Gastric mucosa of 15 healthy volunteers without H. pylori infection (G1), 98 people with atrophic gastritis (G2), and 133 patients with gastric cancer (G3) after H. pylori eradication were collected. Methylation burden of an individual was obtained by microarray analysis as an inverse of the correlation coefficient between the methylation levels of 265,552 genomic regions in the person's gastric mucosa and those in an entirely healthy mucosa.

RESULTS

The methylation burden significantly increased in the order of G1 (n = 4), G2 (n = 18), and G3 (n = 19) and was well correlated with the methylation level of a single marker gene (r = 0.91 for miR124a-3). The average methylation levels of nine driver genes tended to increase according to the risk levels (P = 0.08 between G2 vs G3) and was also correlated with the methylation level of a single marker gene (r = 0.94). Analysis of more samples (14 G1, 97 G2, and 131 G3 samples) yielded significant increases of the average methylation levels between risk groups.

CONCLUSIONS

The methylation level of a single marker gene reflects the methylation burden, which includes driver gene methylation, and thus accurately predicts cancer risk.

Patient-Derived Ex Vivo Cultures and Endpoint Assays with Surrogate Biomarkers in Functional Testing for Prediction of Therapeutic Response

Prediction of therapeutic outcomes is important for cancer patients in order to reduce side effects and improve the efficacy of anti-cancer drugs. Currently, the most widely accepted method for predicting the efficacy of anti-cancer drugs is gene panel testing based on next-generation sequencing. However, gene panel testing has several limitations. For example, only 10% of cancer patients are estimated to have druggable mutations, even if whole-exome sequencing is applied. Additionally, even if optimal drugs are selected, a significant proportion of patients derive no benefit from the indicated drug treatment. Furthermore, most of the anti-cancer drugs selected by gene panel testing are molecularly targeted drugs, and the efficacies of cytotoxic drugs remain difficult to predict. Apart from gene panel testing, attempts to predict chemotherapeutic efficacy using ex vivo cultures from cancer patients have been increasing. Several groups have retrospectively demonstrated correlations between ex vivo drug sensitivity and clinical outcome. For ex vivo culture, surgically resected tumor tissue is the most abundant source. However, patients with recurrent or metastatic tumors do not usually undergo surgery, and chemotherapy may be the only option for those with inoperable tumors. Therefore, predictive methods using small amounts of cancer tissue from diagnostic materials such as endoscopic, fine-needle aspirates, needle cores and liquid biopsies are needed. To achieve this, various types of ex vivo culture and endpoint assays using effective surrogate biomarkers of drug sensitivity have recently been developed. Here, we review the variety of ex vivo cultures and endpoint assays currently available.

Tocilizumab-induced mucosal injury in the terminal ileum mimicking intestinal Behçet's disease: A case report

RATIONALE

Tocilizumab, a humanized anti-interleukin-6 (IL-6) receptor monoclonal antibody, is used for the treatment of adult-onset Still disease (AOSD). Despite its efficacy in many clinical situations, concerns have been raised regarding intestinal mucosal injury in patients receiving tocilizumab.

PATIENT CONCERNS

A 64-year-old woman with a history of AOSD was admitted to our hospital with hematochezia. She had AOSD for 15 years and underwent treatment with biweekly tocilizumab 9 months prior to admission. Colonoscopy revealed a large punched-out ulcer in the terminal ileum. On pathological evaluation, nonspecific enteritis with lymphocytes and eosinophils were seen. Based on the location and shape of the lesion, we suspected intestinal Behçet's disease. However, the ulcer reduced in size over time by discontinuation of tocilizumab without additional drug treatment, indicating that it was a drug-induced ulcer.

DIAGNOSIS

The patient was diagnosed with tocilizumab-induced small intestinal ulcer.

INTERVENTIONS

The patient treated with the discontinuation of tocilizumab.

OUTCOMES

The discontinuation of tocilizumab resulted in ulcer scarring. There was no recurrence of hematochezia.

LESSONS

Tocilizumab can cause deep ulcerative lesions in the terminal ileum, which may resemble intestinal Behçet's disease. It is important to continuously monitor abdominal symptoms during tocilizumab therapy and aggressively perform colonoscopy when hematochezia or abdominal pain is observed.

Efficient Establishment of Bile-Derived Organoids From Biliary Cancer Patients

Patient-derived tumor organoids have considerable potential as an in vitro diagnostic tool for drug susceptibility testing. In the present study, we investigated whether bile collected for diagnostic purposes could be a potential source for the establishment of biliary cancer organoids. Among 68 cases of biliary cancer, we successfully generated 60 bile-derived organoids (BDOs) from individual patients. Consistent with previous reports that described biliary cancer organoids from surgical tissues, the BDOs showed diverse morphologies such as simple cysts, multiloculated cysts, thick capsulated cysts, and solid masses. They also harbored mutations in KRAS and TP53 at frequencies of 15% and 55%, respectively. To enrich the cancer organoids by removing contaminated noncancerous components of BDOs, we attempted to verify the effectiveness of 3 different procedures, including repeat passage, xenografting, and selection with an MDM2 inhibitor for TP53 mutation-harboring BDOs. By monitoring the sequence and expression of mutated TP53, we found that all these procedures successfully enriched the cancer organoids. Our data suggest that BDOs can be established with minimal invasiveness from almost all patients with biliary cancers, including inoperable cases. Thus, despite some limitations with respect to the characterization of BDOs and methods for the enrichment of cancer cell-derived organoids, our data suggest that BDOs could have potential applications in personalized medicine.

Glucose metabolic upregulation via phosphorylation of S6 ribosomal protein affects tumor progression in distal cholangiocarcinoma

BACKGROUND

The prognosis of distal cholangiocarcinoma (dCCA) remains poor; thus, the identification of new therapeutic targets is warranted. Phosphorylated S6 ribosomal protein indicates a mammalian target of rapamycin complex 1 (mTORC1) activity, and mTORC1 plays a central role in controlling cell growth and regulating glucose metabolism. We aimed to clarify the effect of S6 phosphorylation on tumor progression and the glucose metabolic pathway in dCCA.

METHODS

Thirty-nine patients with dCCA who underwent curative resection were enrolled in this study. S6 phosphorylation and the expression of GLUT1 were evaluated by immunohistochemistry, and their relationship with clinical factors was investigated. The effect of S6 phosphorylation on glucose metabolism with PF-04691502 treatment, an inhibitor of S6 phosphorylation, was examined in cancer cell lines by Western blotting and metabolomics analysis. Cell proliferation assays were performed with PF-04691502.

RESULTS

S6 phosphorylation and the expression of GLUT1 were significantly higher in patients with an advanced pathological stage. Significant correlations between GLUT1 expression, S6 phosphorylation, and SUV-max of FDG-PET were shown. In addition, cell lines with high S6 phosphorylation levels showed high GLUT1 levels, and the inhibition of S6 phosphorylation reduced the expression of GLUT1 on Western blotting. Metabolic analysis revealed that inhibition of S6 phosphorylation suppressed pathways of glycolysis and the TCA cycle in cell lines, and then, cell proliferation was effectively reduced by PF-04691502.

CONCLUSION

Upregulation of glucose metabolism via phosphorylation of S6 ribosomal protein appeared to play a role in tumor progression in dCCA. mTORC1 may be a therapeutic target for dCCA.

Efficacy of the Castor Oil-Filled Capsule Method as Preparation for Colon Capsule Endoscopy

BACKGROUND

Colon capsule endoscopy (CCE) is useful as an alternative examination for patients in whom colonoscopy is difficult. The Japanese Association for Capsule Endoscopy has published a recommended regimen for CCE using castor oil, which is becoming a standard examination method for CCE in Japan. However, castor oil has an unpleasant flavor. Therefore, patient acceptance is not good.

OBJECTIVES

The aims were to develop a castor oil-filled capsule and evaluate its feasibility and patient acceptance in a retrospective, comparative study.

METHOD

A dissolution study of pig-derived gelatin capsules filled with castor oil was performed using artificial gastric juice. The CCE excretion rates within battery lifetime, CCE examination times, endoscopic colonic cleansing levels, and patient acceptability between CCE boosters with a castor oil-filled capsule and without castor oil were retrospectively compared using medical information, clinical data, and endoscopic findings at Takada Chuo Hospital from September 2016 to August 2019.

RESULTS

The castor oil-filled capsules were completely disintegrated at approximately 1-3 min in artificial gastric juice. Bowel preparation with oil-filled capsules and without castor oil was performed in 27 and 24 patients, respectively. CCE excretion rates within battery life were 100% and 91.7% (p = 0.217), small bowel transit times were 115 min and 143 min (p = 0.046), colon transit times were 168 min and 148 min (p = 0.733), and adequate colonic cleansing rates were 85.2% and 86.3% (p = 1.000) in patients using bowel preparation with and without oil-filled capsules, respectively. Regarding acceptance, the taste was not problematic in 85.2%, and tolerability for the next CCE was 96.3%.

CONCLUSIONS

CCE using a castor oil-filled capsule method achieved high examination performance and sufficient patient tolerability.

Utility of 5-aminolaevulinic acid fluorescence-guided endoscopic biopsy for malignant mesothelioma in a cat and dog

Malignant mesothelioma (MM) is uncommon in cats and dogs and can be challenging to diagnose. Adequate tissue sampling is required for superior diagnostic accuracy. Protoporphyrin IX, a metabolite of 5-aminolaevulinic acid (5-ALA), is a photosensitiser for photodynamic diagnosis (PDD). To the best of our knowledge, no study has reported the use of 5-ALA-PDD to detect MM in veterinary medicine. The present study describes the use of 5-ALA-PDD for MM diagnosis in a cat and dog, as well as the effectiveness of intracavitary chemotherapy. We evaluated the use of PDD with 5-ALA hydrochloride (5-ALA-PDD) in two cases of MM. A 12-year-old cat presented with a 1-month history of respiratory distress, and a 9-year-old dog presented with a 3-month history of mild abdominal distention. We endoscopically biopsied lesions in both the cases using 5-ALA-PDD. Histopathological examination revealed mesothelioma, and immunohistochemical staining was positive for calretinin. Both patients were treated with carboplatin. The cat died of respiratory failure. Although, the dog's condition improved 21 days after the first chemotherapeutic drug administration, the dog died on day 684 owing to cardiac-related issues. 5-ALA-PDD is thus, safe and feasible for the diagnosis of MM in veterinary medicine.

Spatial and single-cell transcriptomics decipher the cellular environment containing HLA-G+ cancer cells and SPP1+ macrophages in colorectal cancer

The cellular interactions in the tumor microenvironment of colorectal cancer (CRC) are poorly understood, hindering patient treatment. In the current study, we investigate whether events occurring at the invasion front are of particular importance for CRC treatment strategies. To this end, we analyze CRC tissues by combining spatial transcriptomics from patients with a public single-cell transcriptomic atlas to determine cell-cell interactions at the invasion front. We show that CRC cells are localized specifically at the invasion front. These cells induce human leukocyte antigen G (HLA-G) to produce secreted phosphoprotein 1 (SPP1)+ macrophages while conferring CRC cells with anti-tumor immunity, as well as proliferative and invasive properties. Taken together, these findings highlight the signaling between CRC cell populations and stromal cell populations at the cellular level.

Comparison of the improvement in gastric mucosal tissue after Helicobacter pylori eradication between young and elderly people

BACKGROUND AND STUDY AIMS

Helicobacter pylori (H. pylori) infection has been clearly shown to be a cause of gastric cancer, and the incidence of gastric cancer has been shown to decrease with eradication. However, few reports have described the utility of eradication therapy in elderly people. Thus, an investigation focusing on how much actual histological improvement is obtained with eradication therapy in elderly people was conducted.

PATIENTS AND METHODS

This was a retrospective study conducted using medical information of patients diagnosed with H. pylori-associated gastritis and who underwent eradication therapy. The histological improvement was assessed based on changes in the atrophy and intestinal metaplasia scores of the Updated Sydney system from before to after eradication. We investigated the rates of histological improvement in atrophy and intestinal metaplasia one year after and long term more than five years after H. pylori eradication in an elderly group and a younger group.

RESULTS

This study included 221 patients (elderly group 123, younger group 98). In histological atrophy, higher rates of improvement were seen in the corpus than in the antrum, and the rates of cure in the antrum were lower in elderly group than in younger group (p = 0.0282). With regard to intestinal metaplasia, the rates of improvement in the antrum were lower in elderly group than in younger. In long term observation, although the rates of cure in the antrum were lower in elderly, improvements were seen in atrophy scores in most of the patients and intestinal metaplasia scores in about half of patients.

CONCLUSION

Though there is more obvious improvement in the gastric mucosa when H. pylori eradication therapy is performed at a young age, some mucosal improvement can be expected in about half of patients after eradication, even in elderly people.

Disease trends after Helicobacter pylori eradication based on Japanese nationwide claims and the health check-up database

BACKGROUND

Helicobacter pylori (H. pylori) infection is a risk factor for many diseases, including peptic ulcer disease and gastric cancer. While H. pylori eradication therapy can prevent these diseases, potentially unfavorable effects of eradication therapy have also been reported in some diseases, such as gastroesophageal reflux disease (GERD), Barrett’s esophagus (BE), inflammatory bowel disease (IBD), allergic diseases, and metabolic diseases. Consequently, both positive and negative impacts should be considered when assessing the effects of H. pylori eradication therapy.

AIM

To compare the incidence of these diseases before and after H. pylori eradication and to comprehensively assess its effects.

METHODS

This retrospective cohort study used a Japanese nationwide health claims database (April 2009-March 2020), developed by the Japanese Ministry of Health, Labour and Welfare. The database contained almost all health insurance claims data issued in Japan, and specific health check-up data for individuals who took the check-ups. Descriptive statistics were used for the analyses. Patients who received primary eradication therapy were defined as those prescribed medi-cation for H. pylori eradication. New diagnoses, defined as incidence of upper gastrointestinal diseases and IBD, and prevalence of allergic diseases were compared before and after eradication. The incidence and prevalence of each disease were also compared between the 3-year period before eradication (from the 4^th to the 2^nd year prior to the year of eradication) and the 3-year period after eradication (from the 1^st to the 3^rd year after the year of eradication) based on the age category and calendar year and month. Changes in body mass index and proportion of patients with metabolic syndrome (MS) were examined before and after eradication.

RESULTS

We identified 5219731 patients who received primary eradication therapy. The 65-69 years age group had the greatest number of patients in both sexes. There was no significant increase in the incidence of GERD after eradication when considering the effects of aging and reporting period. However, the incidence of BE was higher in the 3-year period after eradication than in the 3-year period before eradication for all age categories (0.02%-0.10% vs < 0.01%-0.05%). The incidence of IBD and prevalence of allergic disease were also higher after eradication. In contrast, the incidence of gastric and duodenal ulcers and gastritis was reduced after eradication. In patients with at least one entry of health check-up data (1701111 patients), the percentage of patients with MS showed a slight increase following eradication (11.0% in the year of eradication and 12.2% after 5 years).

CONCLUSION

The results suggest that H. pylori eradication therapy reduces peptic ulcers and gastritis; however, it is associated with increased incidence of several other chronic diseases.

Involvement of clusterin expression in the refractory response of pancreatic cancer cells to a MEK inhibitor

Constitutive activation of the mitogen-activated protein kinase (MAPK) signaling pathway is essential for tumorigenesis of pancreatic ductal adenocarcinoma (PDAC). To date, however, almost all clinical trials of inhibitor targeting this pathway have failed to improve the outcome of patients with PDAC. We found that implanted MIA Paca2, a human PDAC cell line sensitive to a MAPK inhibitor, PD0325901, became refractory within a week after treatment. By comparing the expression profiles of MIA Paca2 before and after acquisition of the refractoriness to PD0325901, we identified clusterin (CLU) as a candidate gene involved. CLU was shown to be induced immediately after treatment with PD0325901 or expressed primarily in more than half of PDAC cell lines, enhancing cell viability by escaping from apoptosis. A combination of PD0325901 and CLU downregulation was found to synergistically or additively reduce the proliferation of PDAC cells. In surgically resected PDAC tissues, overexpression of CLU in cancer cells was observed immunohistochemically in approximately half of the cases studied. Collectively, our findings highlight the mechanisms responsible for the rapid refractory response to MEK inhibitor in PDAC cells, suggesting a novel therapeutic strategy that could be applicable to patients with PDAC using inhibitor targeting the MAPK signaling pathway and CLU.

GM-CSF-producing CCR2+ CCR6+ Th17 cells are pathogenic in dextran sodium sulfate-induced colitis model in mice

Although excessive immune responses by Th17 cells, a helper T cell subset, are implicated in the pathogenesis of inflammatory bowel disease (IBD), the mechanism by which its localization in an inflamed colon is regulated remains unclear. Chemokines and their receptors are involved in the pathogenesis of IBD, however, the relative significance of each receptor on Th17 cells remains unknown. We generated C-C motif chemokine receptor 2 (CCR2) knockout (KO) and CCR6 KO mice in the syngeneic background using the CRISPR/Cas9 system and found that the phenotypes of experimental colitis worsened in both mutant mice. Surprisingly, the phenotype of colitis in CCR2/CCR6-double knockout (CCR2/6 DKO) mice was opposite to that of the single-deficient mice, with significantly milder experimental colitis (p < .05). The same was true for the symptoms in CCR6 KO mice, but not in wild type mice treated with a CCR2 inhibitor, propagermanium. Colonic CCR2⁺ CCR6⁺ Th17 cells produced a potentially pathogenic cytokine GM-CSF whose levels in the gut were significantly reduced in CCR2/6 DKO mice (p < .05). These results suggest that GM-CSF-producing CCR2⁺ CCR6⁺ Th17 cells are pathogenic and are attracted to the inflamed colon by either CCR2 or CCR6 gradient, which subsequently exacerbates experimental colitis in mice.

Role of EUS combined with a newly modified scoring system to detect pancreatic high-grade precancerous lesions

Backgrounds and Objectives

Although pancreatic cancer (PC) has an extremely poor prognosis, the 5-year survival rate of patients with pancreatic high-grade precancerous lesion without invasive carcinoma (PHP) is favorable. PHP diagnosis and identification of patients requiring intervention are needed. We aimed to validate a modified PC detection scoring system regarding its detection ability for PHP and PC in the general population.

Subjects and Methods

We modified an existing PC detection scoring system that incorporates low-grade risk (LGR) factors (family history, presence of diabetes mellitus [DM] or worsening DM, heavy drinking, smoking, stomach symptoms, weight loss, and pancreatic enzyme) and high-grade risk (HGR) factors (new-onset DM, familial PC, jaundice, tumor biomarkers, chronic pancreatitis, intraductal papillary mucinous neoplasm, cysts, hereditary PC syndrome, and hereditary pancreatitis). Each factor was scored as one point; LGR score ≥3 points and/or HGR score ≥1 point (positive scores) were indicative of PC. The newly modified scoring system incorporated main pancreatic duct dilation as an HGR factor. The PHP diagnosis rate using this scoring system combined with EUS was prospectively analyzed.

Results

Among 544 patients with positive scores, 10 had PHP. The diagnosis rates were 1.8% for PHP and 4.2% for invasive PC. Although the number of LGR and HGR factors tended to increase with PC progression, none of the individual factors were significantly different between patients with PHP and those without lesions.

Conclusion

The newly modified scoring system evaluating multiple factors associated with PC could potentially identify patients with higher risk of PHP or PC.

Differences in clinical features and morphology between differentiated and undifferentiated gastric cancer after Helicobacter pylori eradication

BACKGROUND/AIMS

Although undifferentiated gastric cancer (UGC) diagnosed after Helicobacter pylori eradication (HPE) carries a poor prognosis, characteristics of post-HPE UGC have not been evaluated in detail because of its low incidence. Therefore, we compared the clinicopathologic characteristics of UGC and differentiated gastric cancers (DGC) diagnosed after successful HPE.

METHODS

GC lesions from patients who had successfully completed HPE and who had undergone upper gastrointestinal endoscopy between January 2004 and March 2016 were analyzed. Tumors were divided into DGC and UGC groups. Clinicopathologic factors of background and tumor characteristics were compared using univariate and multiple logistic analyses.

RESULTS

A total of 129 tumors from 115 patients were evaluated; 113 tumors were in the DGC group and 16 in the UGC group. Depressed-type tumors (P = 0.024) and sub-submucosal invasion (P<0.001) were significantly higher in the UGC group. The UGC group had larger tumor diameters (25.9±7.3 mm) than the DGC group (13.2±10.2 mm) (P<0.001). Multivariate analysis showed that female sex (odds ratio [OR] 3.24, 95%CI:1.02-10.37; P = 0.047) and absent follow-up (OR 4.99, 95%CI:1.60-15.57; P = 0.006) were significant independent risk factors for UGC. The DGC group showed a gradually decreasing temporal trend by trend test (P = 0.015), while the UGC group showed a relatively constant incidence over time, although the number of cases was small.

CONCLUSION

UGC was diagnosed even after long time spans following HPE, although the number of cases was small. Female sex, and especially absent follow-up, were risks for post-HPE UGC, suggesting that diligent long-term follow-up after HPE is essential.

[Successful treatment of the diverticular lesion of the colon via EMR with over-the-scope clip (OTSC):a case report]

A 65-year-old woman presented with a flat elevated lesion of about 1cm in the cecal diverticulum during a lower gastrointestinal endoscopy that was performed previously by another physician during a medical checkup. The patient was referred to our department for resection. Considering the risk of perforation owing to the diverticular lesion, positive nonlifting sign, and Group 5 diagnosis on the previous biopsy, EMR with over-the-scope clip (OTSC) (EMRO) was selected, and complete resection was achieved without complications.

COVID-19 vaccination and liver disease

Various vaccines against severe acute respiratory syndrome coronavirus 2 have been developed in response to the coronavirus disease 2019 (COVID-19) global pandemic, several of which are highly effective in preventing COVID-19 in the general population. Patients with chronic liver diseases (CLDs), particularly those with liver cirrhosis, are considered to be at a high risk for severe COVID-19 and death. Given the increased rates of disease severity and mortality in patients with liver disease, there is an urgent need to understand the efficacy of vaccination in this population. However, the data regarding efficacy and safety of COVID-19 vaccination in patients with CLDs is limited. Indeed, several organ-specific or systemic immune-mediated side effects following COVID-19 vaccination, including liver injury similar to autoimmune hepatitis, have been recently reported. Although the number of cases of vaccine-related liver injury is increasing, its frequency, clinical course, and mechanism remain unclear. Here, we review the current findings on COVID-19 vaccination and liver disease, focusing on: (1) The impact of COVID-19 in patients with CLD; (2) The efficacy, safety, and risk-benefit profiles of COVID-19 vaccines in patients with CLD; and (3) Liver injury following COVID-19 vaccination.

Pancreatic cancer with pseudoaneurysm after duckbill-shaped anti-reflux metal stent placement: A case report

A 74-year-old man was diagnosed with unresectable pancreatic cancer with obstructive jaundice. Chemotherapy with gemcitabine and nab-paclitaxel was initiated after placement of a duckbill-shaped anti-reflux metal stent (D-ARMS). A period of 1 month after D-ARMS placement, the patient developed hematemesis and entered severe shock following emergency admission for further evaluation. Contrast-enhanced computed tomography revealed a pseudoaneurysm in the gastroduodenal artery, coincident with the site of D-ARMS placement, and bleeding from the same site was diagnosed. Angiography was performed, and the pseudoaneurysm was successfully treated by transcatheter arterial embolization using coils. The patient was subsequently discharged from hospital and experienced no further bleeding until his death due to an aggravation of the pancreatic cancer after 2 months. We report a case of pancreatic cancer with pseudoaneurysm after D-ARMS placement.

Enhanced phosphorylation of c-Jun by cisplatin treatment as a potential predictive biomarker for cisplatin response in combination with patient-derived tumor organoids

Despite recent advances in sequencing technology and large-scale drug screenings employing hundreds of cell lines, the predictive accuracy of mutation-based biomarkers is still insufficient as a guide for cancer therapy. Therefore, novel types of diagnostic methods using alternative biomarkers would be highly desirable. We have hypothesized that sensitivity-specific changes in the phosphorylation of signaling molecules could be useful in this respect. Here, with the aim of developing a method for predicting the response of cancers to cisplatin using a combination of specific biomarker(s) and patient-derived tumor organoids (PDOs), we found that cisplatin-sensitive cell lines or PDOs showed enhanced phosphorylation of c-Jun (p-c-Jun) within 24 h after cisplatin treatment. We also compared the responses of 6 PDOs to cisplatin with the therapeutic effect of neoadjuvant chemotherapy (docetaxel/cisplatin/5-fluorouracil) in 6 matched patients. Mechanistically, the c-Jun induction was partly related to TNF signaling induced by cisplatin. Our data suggest that enhanced phosphorylation of c-Jun in response to cisplatin treatment could be a predictive biomarker for the efficacy of cisplatin in selected cancer patients.

Acute Cholecystitis Associated with Eosinophilic Granulomatosis with Polyangiitis that Responded to Glucocorticoid Therapy

Eosinophilic granulomatosis with polyangiitis (EGPA) is a systemic disorder characterized by tissue eosinophilic infiltration and vasculitis. Although EGPA causes multiple organ damage, it causes cholecystitis less frequently. We herein report a case of acute cholecystitis associated with EGPA in which successful treatment with glucocorticoid therapy allowed surgery to be avoided. EGPA can present as acute cholecystitis. It is important not to overlook acute cholecystitis associated with EGPA in patients with abdominal pain with peripheral eosinophilia. Furthermore, in cases of mild cholecystitis associated with EGPA that are diagnosed preoperatively, cholecystectomy might be avoided with conservative glucocorticoid treatment.

Effectiveness of second-look endoscopy after gastric endoscopic submucosal dissection in patients taking antithrombotic agents: a multicenter propensity score matching analysis

BACKGROUND

The risk of bleeding after gastric endoscopic submucosal dissection (ESD) in antithrombotic agent users has increased, and its management remains a problem. Second-look endoscopy (SLE) following gastric ESD in antithrombotic agent users may be effective in preventing delayed bleeding, but this requires elucidation. Therefore, this study aimed to investigate the efficacy of SLE in reducing bleeding after gastric ESD in patients receiving antithrombotic agents.

METHODS

This retrospective cohort study was conducted at 19 referral hospitals in Japan. A total of 1,245 patients who were receiving antithrombotic agents underwent gastric ESD between January 2013 and July 2018. The incidence of delayed bleeding was compared between SLE and non-SLE groups using propensity score matching analysis.

RESULTS

Overall, 858 patients (SLE group, 657 patients; non-SLE group, 201 patients) were analyzed. After matching, 198 pairs were created. Delayed bleeding occurred in 10 patients (5.1%) in the SLE group and 16 patients (8.1%) in the non-SLE group [odds ratio (OR) 0.605, 95% confidence interval (CI) 0.23-1.46, p = 0.310]. In the subgroup analysis, SLE reduced the incidence of delayed bleeding in patients receiving heparin bridging therapy (6.3% and 40.0%, respectively; p = 0.004). In the SLE group, prophylactic coagulation did not significantly reduce delayed bleeding compared to the no treatment group (14.6% and 8.6%, respectively; p = 0.140).

CONCLUSIONS

SLE was ineffective in reducing bleeding after gastric ESD in antithrombotic agent users, overall. A prospective comparative study is warranted to definitively evaluate the effectiveness of SLE in reducing bleeding in high-risk patients.

Kyoto international consensus report on anatomy, pathophysiology and clinical significance of the gastro-oesophageal junction

OBJECTIVE

An international meeting was organised to develop consensus on (1) the landmarks to define the gastro-oesophageal junction (GOJ), (2) the occurrence and pathophysiological significance of the cardiac gland, (3) the definition of the gastro-oesophageal junctional zone (GOJZ) and (4) the causes of inflammation, metaplasia and neoplasia occurring in the GOJZ.

DESIGN

Clinical questions relevant to the afore-mentioned major issues were drafted for which expert panels formulated relevant statements and textural explanations.A Delphi method using an anonymous system was employed to develop the consensus, the level of which was predefined as ≥80% of agreement. Two rounds of voting and amendments were completed before the meeting at which clinical questions and consensus were finalised.

RESULTS

Twenty eight clinical questions and statements were finalised after extensive amendments. Critical consensus was achieved: (1) definition for the GOJ, (2) definition of the GOJZ spanning 1 cm proximal and distal to the GOJ as defined by the end of palisade vessels was accepted based on the anatomical distribution of cardiac type gland, (3) chemical and bacterial (Helicobacter pylori) factors as the primary causes of inflammation, metaplasia and neoplasia occurring in the GOJZ, (4) a new definition of Barrett's oesophagus (BO).

CONCLUSIONS

This international consensus on the new definitions of BO, GOJ and the GOJZ will be instrumental in future studies aiming to resolve many issues on this important anatomic area and hopefully will lead to better classification and management of the diseases surrounding the GOJ.

LI-RADS Classification and Outcomes of Hepatocellular Carcinoma Treated With Transcatheter Arterial Chemoembolization Plus Radiofrequency Ablation

AIM

The aim of this study was to clarify the usefulness of the Liver Imaging Reporting and Data System (LI-RADS) for predicting a patient's prognosis after transcatheter arterial chemoembolization (TACE) combined with radiofrequency ablation (TACE-RFA) for hepatocellular carcinoma (HCC) of Barcelona-Clinic Liver Cancer (BCLC) stage 0 or A.

PATIENTS AND METHODS

We retrospectively analyzed cases of patients with HCC who underwent TACE-RFA (Jan 2005 to Dec 2015). Nodules were categorized based on their LI-RADS v2018 core. The LI-RADS category was assigned to each nodule using dynamic contrast-enhanced computed tomography. LR-3, LR-4 and LR-5 nodules were extracted. The overall (OS) and recurrence-free (RFS) survival was assessed among patients with BCLC 0 and BCLC A disease.

RESULTS

Of the 64 nodules extracted, 22 were LR-3 or -4 (mean±standard deviation=14.8±6.7 mm) and 42 were LR-5 (17.1±6.9 mm). Regarding OS, there was no significant difference between those with LR-3 or -4 and LR-5 (p=0.278). In terms of RFS, there was a significant difference between those with LR-3 or -4 and those with LR-5 (p=0.03). In particular, patients with BCLC A with LR-5 nodules had significantly poorer RFS than those with LR-3 or -4 (p=0.016) nodules.

CONCLUSION

For patients with BCLC A, LR-3 or -4 nodules are associated with a better prognosis than LR-5 nodules.

Saireito, a Japanese herbal medicine, alleviates leaky gut associated with antibiotic-induced dysbiosis in mice

Antibiotics disrupt normal gut microbiota and cause dysbiosis, leading to a reduction in intestinal epithelial barrier function. Disruption of the intestinal epithelial barrier, which is known as “leaky gut”, results in increased intestinal permeability and contributes to the development or exacerbation of gastrointestinal diseases such as inflammatory bowel disease and irritable bowel syndrome. We have previously reported on a murine model of intestinal epithelial barrier dysfunction associated with dysbiosis induced by the administration of ampicillin and vancomycin. Saireito, a traditional Japanese herbal medicine, is often used to treat autoimmune disorders including ulcerative colitis; the possible mechanism of action and its efficacy, however, remains unclear. In this study, we examined the efficacy of Saireito in our animal model for leaky gut associated with dysbiosis. C57BL/6 mice were fed a Saireito diet for the entirety of the protocol (day1-28). To induce colitis, ampicillin and vancomycin were administered in drinking water for the last seven consecutive days (day22-28). As previously demonstrated, treatment with antibiotics caused fecal occult bleeding, cecum enlargement with black discoloration, colon inflammation with epithelial cell apoptosis, and upregulation of pro-inflammatory cytokines. Oral administration of Saireito significantly improved antibiotics-induced fecal occult bleeding and cecum enlargement by suppressing inflammation in the colon. Furthermore, Saireito treatment ensured the integrity of the intestinal epithelial barrier by suppressing apoptosis and inducing cell adhesion proteins including ZO-1, occludin, and E-cadherin in intestinal epithelial cells, which in turn decreased intestinal epithelial permeability. Moreover, the reduced microbial diversity seen in the gut of mice treated with antibiotics was remarkably improved with the administration of Saireito. In addition, Saireito altered the composition of gut microbiota in these mice. These results suggest that Saireito alleviates leaky gut caused by antibiotic-induced dysbiosis. Our findings provide a potentially new therapeutic strategy for antibiotic-related gastrointestinal disorders.

Clinicopathological characteristics of pancreatic acinar cell metaplasia associated with Helicobacter pylori infection

Background

Pancreatic acinar cell metaplasia (PACM) has been rarely reported in the gastric mucosa. In the present study, we aimed to elucidate the clinical and pathological characteristics of PACM associated with Helicobacter pylori (H. pylori).

Method

5930 patients who underwent five- or two-point gastric biopsy according to the updated Sydney system (USS) by upper gastrointestinal endoscopy were enrolled. The patients were categorized into current H. pylori infection (CHI), post-H. pylori eradication (PHE), and non-H. pylori infection (NHI) groups according to the H. pylori infection status, and the frequency and location of PACM were compared. Additionally, a case–control study was performed to compare the USS scores between patients with CHI and PACM and those with CHI but not PACM.

Result

The frequencies of PACM were 0.49% (10/2039), 0.75% (25/3332), and 0% (0/559) in the CHI, PHE, and NHI groups, respectively. PACM was found in the greater curvature of the antrum in 33 of the 35 patients with PACM. Among the patients with CHI, the inflammation scores in the greater curvature of the antrum and the greater curvature of the corpus were lower in patients with PACM than in those without PACM.

Conclusion

Although rarely reported in the gastric mucosa, PACM was closely related to H. pylori infection, especially in the antrum, and was associated with relatively mild inflammation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02338-2.

AB0653 The association of autoantibodies with morbidity and mortality of scleroderma renal crisis in Japan

Background

The morbidity of scleroderma renal crisis (SRC) and autoantibodies in systemic sclerosis (SSc) vary by races and regions. Anti-RNA polymerase III is associated with SRC in America and European countries. However, the association of autoantibodies with SRC had not been elucidated in Japan.

Objectives

We aimed to investigate the association of autoantibodies with morbidity and mortality of SRC in Japan.

Methods

The clinical characteristics and mortality of 330 patients with systemic sclerosis (SSc) at Kyoto University Hospital were retrospectively analyzed, focusing on anti-centromere, anti-RNA polymerase III, anti-topoisomerase I, and anti-U1-RNP. Logistic regression analyses were performed to examine the association of autoantibodies with the development and mortality of SRC. Kaplan-Meier survival analysis was performed comparing the groups classified by autoantibodies.

Results

Anti-centromere (n = 177/318, 56%), anti-topoisomerase I (n = 80/311, 26%), anti-RNA polymerase III (n = 27/204, 13%), and anti-U1-RNP (n = 24/305, 8%) were found in SSc patients (n = 330). SRC was observed in 24 out of 330 SSc patients, including anti-topoisomerase I (n = 12/24, 50%), anti-RNA polymerase III (n = 7/24, 29%), anti-U1-RNP (n = 5/24, 21%), and anti-centromere (n = 3/24, 13%). Anti-U1-RNP (odds ratio [95% confidence interval], 3.63 [1.11–10.2]), anti-RNA polymerase III (3.29 [1.16–8.70]), and anti-topoisomerase I (3.22 [1.37–7.57]) were associated with the development of SRC. All patients with SRC were treated with ACE inhibitors and the 1-year survival rate was 54%. Anti-topoisomerase I was associated with the 1-year mortality of SRC (6.00 [1.11–41.1]). When the survival rate was compared between the patients positive for anti-topoisomerase I (n=12) and negative for anti-topoisomerase I (n=12), the 1-year survival rate was 33% vs 75% (p=0.041), respectively (Figure 1A). Furthermore, the 1-year survival of anti-centromere (100%), anti-RNA polymerase III (83%), and others/not detected (50%) were shown in patients negative for anti-topoisomerase I (Figure 1B).

Figure 1.

Overall survival of patients with SRC according to the type of autoantibodies.

(A) The survival rates in SRC patients who were positive for anti-topoisomerase I (solid line, n = 12) and those who were negative for anti-topoisomerase I (dotted line, n = 12).

(B) SRC patients negative for anti-topoisomerase I were classified as patients with anti-RNA polymerase III (dotted line, n = 6), anti-centromere (broken line, n = 2), and others/not detected (chain line, n = 4).

Conclusion

Specific SSc-related autoantibodies were associated with the morbidity and mortality in SRC.

References

[1]Nihtyanova SI, et al. Arthritis Rheumatol 2020;72(3):465-76.

[2]Hamaguchi Y, et al. Arthritis Rheumatol 2015;67(4):1045-52.

Table 1.

Univariate logistic regression analysis for mortality in SRC (n = 24).

VariablesOdds ratio (95% CI)P valueAge1.07 (0.99, 1.16)0.08Female sex3.00 (0.32, 66.6)0.38Diffuse/limited (diffuse %)0.25 (0.04, 1.36)0.12BMI0.67 (0.41, 0.93)0.049Modified Rodnan skin score0.95 (0.88, 1.02)0.15Digital ulcer0.52 (0.10, 2.63)0.43Reflux esophagitis0.60 (0.02, 17.1)0.73Pulmonary hypertension7.50 (1.17, 69.2)0.046Pleural effusion7.20 (1.23, 62.0)0.04Glucocorticoid use3.86 (0.65, 32.4)0.16Hemoglobin0.55 (0.25, 1.01)0.09Platelet1.00 (0.98, 1.01)0.44Total protein0.17 (0.02, 0.69)0.04Creatinine0.95 (0.67, 1.24)0.69CRP0.90 (0.67, 1.17)0.46Anti-topoisomerase I6.00 (1.11, 41.1)0.048Anti-centromere7.4x10-9 (--, 0.93)1.00Anti-RNA polymerase III0.36 (0.04, 2.18)0.29Anti-U1-RNP0.74 (0.08, 5.49)0.77

Disclosure of Interests

None declared

Establishment of a reference panel of Helicobacter pylori strains for antimicrobial susceptibility testing

BACKGROUND

Eradication treatment for Helicobacter pylori gastritis is covered by national health insurance since 2013 in Japan. However, eradication failure due to the increase of antimicrobial resistance has become a serious problem. The present study aims to establish a reference panel of Japanese H. pylori strains for antimicrobial susceptibility testing.

METHOD

A total of 28 strains were collected from 4 medical facilities in Japan. Antimicrobial susceptibility tests (ASTs) to clarithromycin (CLR), amoxicillin (AMX), and metronidazole (MNZ), were used to select standard reference strains. Complete genome sequences were also determined.

RESULTS

Three H. pylori strains (JSHR3, JSHR6 and JSHR31) were selected as standard reference strains by the Japanese Society for Helicobacter Research (JSHR). The minimum inhibitory concentrations (MICs) of the antibiotics against these 3 strains by agar dilution method with Brucella-based horse-serum-containing agar medium were as follows: JSHR3 (CLR 16 μg/ml, AMX 0.032 μg/ml and MNZ 4 μg/ml), JSHR6 (CLR 0.016 μg/ml, AMX 0.032 μg/ml and MNZ 4 μg/ml), and JSHR31 (CLR 16 μg/ml, AMX 1 μg/ml and MNZ 64 μg/ml).

CONCLUSIONS

A reference panel of H. pylori JSHR strains was established. The panel consisted of JSHR6, which was antibiotic-susceptible, JSHR3, which was CLR-resistant, and JSHR31, which was multi-resistant. This reference panel will be essential for standardized ASTs before the optimal drugs are selected for eradication treatment.

POS0532 DRUG RETENTION OF BIOLOGICS OR JAK INHIBITORS IN PATIENTS WITH DIFFICULT-TO-TREAT RHEUMATOID ARTHRITIS: RESULTS FROM THE ANSWER COHORT

Background

Difficult-to-treat rheumatoid arthritis (D2T RA) is defined as RA in which disease activity is uncontrolled despite the use of two or more biologics or Janus kinase inhibitors (JAKi) with different mechanisms of action (MOA).

Objectives

To explore the optimal treatment strategy for D2T RA, we evaluated the drug retention, efficacy, and reasons for discontinuation of biologics or JAKi used for patients with D2T RA in a longitudinal multicenter cohort.

Methods

RA patients with clinical disease activity index (CDAI) >10 despite the use of at least two biologics or JAKi with different MOA and further treated with biologics or JAKi were included. The drug retention rates of biologics (TNFi, IL-6Ri, and CTLA4-Ig) or JAKi were estimated at 12 months using the Kaplan-Meier method and adjusted for potential confounders (age, sex, disease duration, concomitant MTX and PSL use, and the number of switched biologics or JAKi) using Cox proportional hazards models.

Results

A total of 251 treatment courses (TCs) from 167 patients were included (TNFi: 97 TCs, IL-6Ri: 67 TCs, CTLA4-Ig: 27 TCs, JAKi: 60 TCs). Baseline characteristics showed no difference in age, sex, disease duration, ACPA positivity, CDAI, and concomitant MTX and PSL use between the four groups. Drug retention excluding non-toxic reasons and remission was significantly higher in patients treated with JAKi or IL-6Ri than in patients treated with TNFi or CTLA4-Ig (P=0.00172). Multivariate analysis using Cox proportional hazards models demonstrated that discontinuation of the drug was associated with the use of TNFi or CTLA4-Ig (HR: 3.29, 95%CI: 1.15-9.42, P=0.027) and concomitant PSL use (HR: 1.14, 95%CI: 1.04-1.26, P=0.0084). In terms of disease activity evaluated with CDAI, no difference was observed between the four groups at 3 months (P=0.90), at 6 months (P=0.77), and at 12 months (P=0.75).

Conclusion

In patients with D2T RA, JAKi or IL-6Ri may have treatment advantages compared with TNFi or CTLA4-Ig.

References

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Nagy G, Roodenrijs NMT, Welsing PM, Kedves M, Hamar A, van der Goes MC, Kent A, Bakkers M, Blaas E, Senolt L, Szekanecz Z, Choy E, Dougados M, Jacobs JW, Geenen R, Bijlsma HW, Zink A, Aletaha D, Schoneveld L, van Riel P, Gutermann L, Prior Y, Nikiphorou E, Ferraccioli G, Schett G, Hyrich KL, Mueller-Ladner U, Buch MH, McInnes IB, van der Heijde D, van Laar JM.

Ann Rheum Dis. 2021 Jan;80(1):31-35.

[2] Prevalence and predictive factors of difficult-to-treat rheumatoid arthritis: the KURAMA cohort.

Watanabe R, Hashimoto M, Murata K, Murakami K, Tanaka M, Ohmura K, Ito H, Matsuda S.

Immunol Med. 2021 May 25:1-10.

Disclosure of Interests

Ryu Watanabe Speakers bureau: Eli Lilly, Mitsubishi Tanabe, Pfizer, Sanofi, AbbVie, Asahi Kasei, Eisai, Bristol-Myers Squibb, UCB Japan, Chugai, Janssen, Astellas, Nippon Shinyaku, Daiichi Sankyo, Gilead Sciences Japan, and Boehringer ingelheim., Tadashi Okano Speakers bureau: Asahi Kasei, Astellas, Abbvie, Amgen, Ayumi, Chugai, Daiichi-Sankyo, Eisai, Eli Lilly, Gilead Sciences, Janssen, Kyowa Kirin, Mitsubishi Tanabe, Novartis, Ono, Pfizer, Sanofi, Takeda, UCB, Grant/research support from: Asahi Kasei, Abbvie, Chugai, Eisai, Mitsubishi Tanabe, Shinsuke Yamada: None declared, Wataru Yamamoto: None declared, Koichi Murata Speakers bureau: Eisai Co., Ltd., Chugai Pharmaceutical Co., Ltd.; Asahi Kasei Pharma Corp.; and Mitsubishi Tanabe Pharma Co., and Daiichi Sankyo Co. Ltd., Kosaku Murakami: None declared, Kosuke Ebina Speakers bureau: AbbVie, Amgen, Asahi-Kasei, Astellas, Ayumi, Bristol-Myers Squibb, Chugai, Eisai, Eli Lilly, Janssen, Mitsubishi-Tanabe, Ono Pharmaceutical, Pfizer, Sanofi, and UCB Japan., Grant/research support from: AbbVie, Amgen, Asahi-Kasei, Astellas, Chugai, Eisai, Mitsubishi-Tanabe, Ono Pharmaceutical, Teijin Pharma, and UCB Japan, Yuichi Maeda Speakers bureau: Eli Lilly Japan K.K., Chugai Pharmaceutical Co. Ltd., Pfizer Inc., Bristol Myers Squibb, and Mitsubishi Tanabe Pharma Corporation., Sadao Jinno Speakers bureau: AbbVie G.K., Asahi Kasei Pharma., Bristol-Myers Squibb., Chugai Pharmaceutical Co., Ltd., Eisai Co., Ltd., Eli Lilly Japan K.K., Janssen Pharmaceutical K.K., and Mitsubishi Tanabe Pharma, and Ono Pharmaceutical Co, Iku Shirasugi: None declared, Yonsu Son: None declared, Hideki Amuro Speakers bureau: Chugai Pharmaceutical Co.,Ltd, Masaki Katayama: None declared, Ryota Hara: None declared, Kenichiro Hata Speakers bureau: AbbVie, Asahi-Kasei, Chugai, Janssen, Mitsubishi-Tanabe, Eisai, Ayaka Yoshikawa: None declared, Motomu Hashimoto Grant/research support from: Abbvie, Asahi-Kasei, Brystol-Meyers, Eisai, Eli Lilly, Novartis Pharma.

Accurate Evaluation of Residual Common Bile Duct Stones by Endoscopic Ultrasound: A Two-Step Check Method for Residual Stone Clearance

BACKGROUND/AIMS

Residual common bile duct (CBD) stones occasionally become symptomatic after stone removal with endoscopic retrograde cholangiopancreatography (ERCP) upon removal of the endoscopic biliary stent (EBS). An accurate evaluation of residual stones before stent removal is necessary. This study evaluated a new two-step check method using endoscopic ultrasound (EUS) for the detection of residual stones after ERCP stone removal.

METHODS

Fifty-six patients who underwent CBD stone removal and EBS placement were prospectively enrolled. Residual stones were evaluated by the check method. EBS was removed at the time of the check method or at a later time of residual stone removal. The primary outcome was to evaluate the efficacy of this check method.

RESULTS

Residual CBD stone/sludge was detected in 20 of 56 patients (35.7%; stones: 28.6%, sludge: 7.1%) by the check method and removed by the ERCP procedure at a later time. After stent and final stone removal, patients were followed for an average of 211 days; cholangitis recurred in only 1.8% of patients. There were no adverse events associated with the check method. Temporary EBS prevented the recurrence of cholangitis by residual stone and caused no adverse events in the pancreatobiliary tract until the two-step check method (median, 113 days; range, 17-232 days).

CONCLUSION

The new check method may be ideal and feasible for EBS removal because recurrences are very rare when a clear CBD has been verified, and an additional ERCP procedure is also possibly avoided.

Evaluation of screening tests for autoimmune gastritis in histopathologically confirmed Japanese patients, and re-evaluation of histopathological classification

Background

The aims of the present study are to evaluate non-invasive screening tests for autoimmune gastritis (AIG) and re-evaluate histopathological classification.

Methods

We screened candidates of AIG in JCHO Shiga Hospital between May 2012 and January 2020. The screening criteria were as follows: endoscopic O-p atrophy with Updated Kimura–Takemoto classification, 3 + pepsinogen (PG) test, low serum vitamin B₁₂ or elevated serum gastrin with positive anti-parietal cell (PC) or intrinsic factor antibodies. We evaluated the screening criteria in the patients who were histopathologically confirmed as AIG, and re-evaluated histopathological staging in clinical aspects.

Results

Twenty-two of 28 (78.6%) patients who met the screening criteria were histopathologically confirmed as AIG. Common clinical findings in the AIG patients were 10 × or greater anti-PC antibody, elevated serum gastrin greater than 172 pg/mL and endoscopic atrophy O-1 or greater. The areas under the curve of PG I, PG II and PG I/II ratio were 0.81, 0.29 and 0.98, respectively. Among histopathologically confirmed AIG patients, 4 and 18 patients were histopathologically classified into florid and end stages, respectively, while no patients into early stage. We could not find a significant difference between florid and end stages in the screening items studied.

Conclusions

Florid and end stages in histopathological classification are both advanced-stage AIG in clinical aspects. Our screening criteria without biopsy are applicable to screen clinically-advanced AIG with 78.6% positive predictive value. PG I and PG I/II ratio may be useful to screen AIG. However, we may need other criteria to screen early stage of AIG.

Intersexual flower differences in an andromonoecious species: small pollen-rich staminate flowers under resource limitation

Andromonoecy, the presence of perfect and staminate flowers in the same individual, has evolved repeatedly in angiosperms. The staminate flowers are generally smaller than the perfect flowers in species that produce staminate flowers plastically when resources are limited. The smaller staminate flowers are expected to be less attractive to pollinators and have reduced size-matching with pollinators than perfect flowers. We hypothesized that these potential disadvantages of staminate versus perfect flowers facilitate the evolution of sex-specific floral morphology, such as allometric relationship between flower size and male reproductive organ. We compared six floral morphology traits, pollen production, pollinator visits and pollen removal from anthers between staminate and perfect flowers in several natural Commelina communis populations. Nectarless and zygomorphic C. communis flowers have polymorphic stamens with attracting, feeding and pollinating anthers and were visited by diverse pollinators. Staminate flowers were significantly smaller than perfect flowers, despite a large overlap in size between sexes. The lengths of pollinating stamens did not differ between staminate and perfect flowers, and staminate flowers produced significantly more pollen. We observed significantly more pollinator visits to perfect flowers than to staminate flowers. By contrast, pollen removal from pollinating stamens was significantly higher in staminate flowers than in perfect flowers. There is sexual dimorphism in flower morphology in C. communis. Staminate flowers with smaller attraction organs, similar pollinating stamens and higher pollen production assure higher pollen donor success relative to perfect flowers. Our results suggest that the morphological changes in staminate flowers enhance pollination success, even with limited resources.

Genomic differentiation within East Asian Helicobacter pylori

The East Asian region, including China, Japan and Korea, accounts for half of gastric cancer deaths. However, different areas have contrasting gastric cancer incidences and the population structure of Helicobacter pylori in this ethnically diverse region is yet unknown. We aimed to investigate genomic differences in H. pylori between these areas to identify sequence polymorphisms associated with increased cancer risk. We analysed 381 H. pylori genomes collected from different areas of the three countries using phylogenetic and population genetic tools to characterize population differentiation. The functional consequences of SNPs with a highest fixation index (Fst) between subpopulations were examined by mapping amino acid changes on 3D protein structure, solved or modelled. Overall, 329/381 genomes belonged to the previously identified hspEAsia population indicating that import of bacteria from other regions of the world has been uncommon. Seven subregional clusters were found within hspEAsia, related to subpopulations with various ethnicities, geographies and gastric cancer risks. Subpopulation-specific amino acid changes were found in multidrug exporters (hefC), transporters (frpB-4), outer membrane proteins (hopI) and several genes involved in host interaction, such as a catalase site, involved in H₂O₂ entrance, and a flagellin site mimicking host glycosylation. Several of the top hits, including frpB-4, hefC, alpB/hopB and hofC, have been found to be differentiated within the Americas in previous studies, indicating that a handful of genes may be key to local geographic adaptation. H. pylori within East Asia are not homogeneous but have become differentiated geographically at multiple loci that might have facilitated adaptation to local conditions and hosts. This has important implications for further evaluation of these changes in relation to the varying gastric cancer incidence between geographical areas in this region.