Toshihide Tamura

The Superiority of Vonoprazan-based First-line Triple Therapy with Clarithromycin: A Prospective Multi-center Cohort Study on Helicobacter pylori Eradication

Objective We evaluated the safety and efficacy of vonoprazan-based amoxicillin and clarithromycin 7-day triple therapy (VAC) in comparison to proton pump inhibitor (PPI)-based (PAC) as a first-line treatment and vonoprazan-based amoxicillin and metronidazole 7-day triple therapy (VAM) in comparison to PPI-based (PAM) as a second-line treatment for the eradication of Helicobacter pylori in Japan. Methods We performed a non-randomized, multi-center, parallel-group study to compare first-line VAC to PAC and second-line VAM to PAM. A pre-planned subgroup analysis on CAM resistance was also performed. Safety was evaluated with an adverse effects questionnaire (AEQ), which was completed by patients during therapy. Results The first-line eradication rates (ER) in the intention-to-treat (ITT) and per protocol (PP) analyses were 84.9% (95% CI: 81.9-87.6%, n=623) and 86.4% (83.5-89.1%, n=612), respectively, for VAC and 78.8% (75.3-82.0%, n=608) and 79.4% (76.0-82.6%, n=603), respectively, for PAC. The ER of VAC was higher than that of PAC in the ITT (p=0.0061) and PP analyses (p=0.0013). The ERs for VAC in patients with CAM-resistant and CAM-susceptible bacteria were 73.2% (59.7-84.2%, n=56) and 88.9% (83.4-93.1%, n=180), respectively. PAC was associated with higher AEQ scores for diarrhea, nausea, headache, and general malaise. In the second-line ITT and PP analyses VAM achieved ERs of 80.5% (74.6-85.6%, n=216) and 82.4% (76.6-87.3%, n=211), respectively, while PAM achieved ERs of 81.5% (74.2-87.4%, n=146) and 82.1% (74.8-87.9%, n=145), respectively. No significant differences were observed in the ITT (p=0.89) or PP (p=1.0) analyses. Conclusion The ER of first-line VAC was higher than that of PAC, but still <90%. No difference was observed between second-line VAM and PAM. Vonoprazan-based triple therapy was safe and well tolerated.

Vonoprazan- vs proton-pump inhibitor-based first-line 7-day triple therapy for clarithromycin-susceptible Helicobacter pylori: A multicenter, prospective, randomized trial

The eradication rate of vonoprazan‐based first‐line triple therapy (combined with clarithromycin and amoxicillin) (V‐AC) was reported to be 97.6% in patients with clarithromycin (CAM)‐susceptible Helicobacter pylori in a phase III study, whereas our real‐world, prospective, multicenter cohort study yielded an eradication rate <90%.

Intestine-specific homeobox (ISX) induces intestinal metaplasia and cell proliferation to contribute to gastric carcinogenesis.

BackgroundHelicobacter pylori induces chronic inflammation and intestinal metaplasia (IM) through genetic and epigenetic changes and activation of intracellular signaling pathways that contribute to gastric carcinogenesis. However, the precise mechanism of IM in gastric carcinogenesis has not been fully elucidated. We previously found that intestine-specific homeobox (ISX) mRNA expression increased in organoids cultured from Helicobacter-infected mouse mucosa. In this study, we elucidate the role of ISX in the development of IM and gastric carcinogenesis.MethodsISX expression was assessed in Helicobacter-infected mouse and human gastric mucosa. MKN45 gastric cancer cells were co-cultured with H. pylori to determine whether Helicobacter infection induced ISX expression. We established stable MKN45 transfected cells expressing ISX (Stable-ISX MKN45) and performed a spheroid colony formation assay and a xenograft model. We performed ISX immunohistochemistry in cancer and adjacent gastric tissues.ResultsISX expression was increased in mouse and human gastric mucosa infected with Helicobacter. The presence of IM and H. pylori infection in human stomach was correlated with ISX expression. H. pylori induced ISX mRNA and protein expression. CDX1/2, cyclinD1, and MUC2 were upregulated in Stable-ISX MKN45, whereas MUC5AC was downregulated. Stable-ISXMKN45 cells formed more spheroid colonies, and had high tumorigenic ability. ISX expression in gastric cancer and adjacent mucosa were correlated.ConclusionsISX expression induced by H. pylori infection may lead to IM and hyperproliferation of gastric mucosa through CDX1/2 and cyclinD1 expression, contributing to gastric carcinogenesis.

First-Line Helicobacter pylori Eradication with Vonoprazan, Clarithromycin, and Metronidazole in Patients Allergic to Penicillin

Aim To assess the efficacy of 7-day first-line Helicobacter pylori eradication with vonoprazan (VPZ), clarithromycin (CAM), and metronidazole (MNZ) in patients with penicillin allergy. Methods Patients with penicillin allergy, diagnosed with Helicobacter pylori infection and did not have history of Helicobacter pylori eradication, were eligible for the study. Twenty patients were prospectively treated with 20u2009mg VPZ twice daily, 200 or 400u2009mg CAM twice daily, and 250u2009mg MNZ twice daily for 7 days. We also collected the data from 30 patients retrospectively treated with proton pump inhibitor (PPI), CAM, and MNZ. Safety was evaluated in patients completing an adverse effect questionnaire. Results Both the intention-to-treat and per-protocol effectiveness of VPZ-based eradication were 100% (95% CI: 86.1–100%; n = 20). The eradication rates of PPI-based regimen were 83.3% (95% CI: 65.3–94.4%) in the ITT and 82.7% (95% CI: 64.2–94.2%) in the PP analyses. Abdominal fullness was more frequent in VCM compared to PCM. However, all patients with VCM regimen had taken 100% of their course of medication. Conclusion Triple therapy with VPZ, CAM, and MNZ is well tolerated and effective for eradicating Helicobacter pylori in patients allergic to penicillin. This study was registered in the UMIN Clinical Trials Registry as UMIN000016335.

Helicobacter-induced gastric inflammation alters the properties of gastric tissue stem/progenitor cells

BackgroundAlthough Helicobacter-induced gastric inflammation is the major predisposing factor for gastric carcinogenesis, the precise mechanism by which chronic gastritis causes gastric cancer remains unclear. Intestinal and spasmolytic polypeptide-expressing metaplasia (SPEM) is considered as precancerous lesions, changes in epithelial tissue stem/progenitor cells after chronic inflammation has not been clarified yet. In this study, we utilized three-dimensional gastric epithelial cell culture systems that could form organoids, mimicking gastric epithelial layer, and characterized the changes in epithelial cells after chronic Helicobacter felis infection.MethodsWe used three mice model; 1) long-term H. felis infection, 2) H. felis eradication, and 3) MNU chemical carcinogenesis model. We performed cRNA microarray analysis after organoid culture, and analyzed the effects of chronic gastric inflammation on tissue stem cells, by the size of organoid, mRNA expression profile and immunohistochemical analysis.ResultsThe number of organoids cultured from gastric epithelial cells was significantly higher in organoids isolated from H. felis-infected mice compared with those from uninfected gastric mucosa. Based on the mRNA expression profile, we found that possible stem cell markers such as Cd44, Dclk1, and genes associated with the intestinal phenotype, such as Villin, were increased in organoids isolated from H. felis-infected mucosa compared with the control. The upregulation of these genes were cancelled after H. felis eradication. In a xenograft model, tumors were generated only from organoids cultured from carcinogen-treated gastric mucosa, not from H. felis infected mucosa or control organoids.ConclusionsOur results suggested that, as a possible mechanism of gastric carcinogenesis, chronic inflammation induced by H. felis infection increased the number of tissue stem/progenitor cells and the expression of stem cell markers. These findings suggest that chronic inflammation may alter the direction of differentiation toward undifferentiated state and that drawbacks may enable cells to redifferentiate to intestinal metaplasia or neoplasia.

Effects of Vonoprazan Compared with Esomeprazole on the Healing of Artificial Postendoscopic Submucosal Dissection Ulcers: A Prospective, Multicenter, Two-Arm, Randomized Controlled Trial

Background Vonoprazan affords more clinical benefits than proton pump inhibitors (PPIs) during the healing of gastroduodenal ulcers. However, it remains controversial whether vonoprazan is more effective than PPIs when used to heal artificial ulcers arising after endoscopic submucosal dissection (ESD). Aim This study investigated the effects of vonoprazan compared with esomeprazole on the healing of post-ESD artificial ulcers. Methods Sixty patients who underwent gastric ESD between May 2015 and May 2017 were randomized to treatment with vonoprazan (V group) or esomeprazole (E group) for 8 weeks. Upper endoscopy was performed at 4 and 8 weeks after ESD, and drug effects were estimated based on the ulcer healing rates and shrinkage rates. Results Fifty-three patients were analyzed. The respective 4- and 8-week ulcer healing rates did not differ significantly between V and E groups (8.0 versus 11.5%, P = 0.669; 88.9 versus 84.6%, P = 0.420). Similarly, the respective 4- and 8-week ulcer shrinkage rates did not differ significantly between V and E groups (96.8 versus 97.5%, P = 0.656; 100 versus 100%, P = 0.257). Conclusion The healing of artificial ulcers after ESD did not differ using vonoprazan or esomeprazole. Both vonoprazan and esomeprazole were effective when used to promote artificial ulcer healing after ESD.

Response to: Comment on “First-Line Helicobacter pylori Eradication with Vonoprazan, Clarithromycin, and Metronidazole in Patients Allergic to Penicillin”

We thank Dr. Kashani and Dr. Abadi [1] for their interest in our article [2]. In Japan, seven-day vonoprazan-containing triple therapy with clarithromycin and amoxicillin or vonoprazan-containing triple therapy with metronidazole and amoxicillin are approved regimens [3], but vonoprazancontaining triple therapy with clarithromycin and metronidazole is not approved and is used only in clinical trials which was approved by the ethics committee. Thus, people who cannot be given the standard triple therapy due to being allergic to penicillin are the subjects of this study. In addition, these patients cannot be covered by their medical insurance system for Helicobacter pylori eradication and related examinations, so it is difficult to add antibiotic susceptibility testing after the diagnosis of H. pylori infection for cost and ethical reason (this study was not designed to choose regimen by antibiotic resistance result). About the sample size, as we have also written the reason is the rate of patients allergic to penicillin, which makes it difficult to recruit many patients for this type of study. These are the explanations overall. We also answer each question: (i) Generalization of the finding: We think the efficacy of this regimen is influenced by metronidazole resistance rates. In Japan, the metronidazole resistance rate is not high, and it is reported that metronidazole-containing triple therapy as a firstline therapy showed high eradication rate (ER) [4]. It is an important point that the vonoprazan, clarithromycin, and metronidazole regimen demonstrated excellent ER in areas with a high rate of clarithromycin resistance in two studies [2, 5], but these were performed in a country with a low rate of metronidazole resistance compared to other countries. We hope this regimen will be useful in countries with high clarithromycin but low metronidazole resistance rates as eradication regimen for those allergic to penicillin instead of PPI-based triple therapy with clarithromycin and metronidazole.

Correction to: Helicobacter -induced gastric inflammation alters the properties of gastric tissue stem/progenitor cells

CorrectionUnfortunately, the original article [1] contained an error incorporated during production. A duplicated version of Tablexa01 was published in place of Tablexa02. Tablexa02 has been corrected in the original article and is also included correctly below.

c-Jun N-terminal kinase in pancreatic tumor stroma augments tumor development in mice

Pancreatic ductal adenocarcinoma (PDAC) is a life‐threatening disease and there is an urgent need to develop improved therapeutic approaches. The role of c‐Jun N‐terminal kinase (JNK) in PDAC stroma is not well defined even though dense desmoplastic reactions are characteristic of PDAC histology. We aimed to explore the role of JNK in PDAC stroma in mice. We crossed Ptf1aCre/+;KrasG12D/+ mice with JNK1−/− mice to generate Ptf1aCre/+;KrasG12D/+;JNK1−/− (Kras;JNK1−/−) mice. Tumor weight was significantly lower in Kras;JNK1−/− mice than in Kras;JNK1+/− mice, whereas histopathological features were similar. We also transplanted a murine PDAC cell line (mPC) with intact JNK1 s.c. into WT and JNK1−/− mice. Tumor diameters were significantly smaller in JNK1−/− mice. Phosphorylated JNK (p‐JNK) was activated in α‐smooth muscle actin (SMA)‐positive cells in tumor stroma, and mPC‐conditioned medium activated p‐JNK in tumor‐associated fibroblasts (TAF) in vitro. Relative expression of Ccl20 was downregulated in stimulated TAF. Ccl20 is an important chemokine that promotes CD8+ T‐cell infiltration by recruitment of dendritic cells, and the number of CD8+ T cells was decreased in Kras;JNK1+/− mice compared with Kras;JNK1−/− mice. These results suggest that the cancer secretome decreases Ccl20 secretion from TAF by activation of JNK, and downregulation of Ccl20 secretion might be correlated with reduction of infiltrating CD8+ T cells. Therefore, we concluded that inhibition of activated JNK in pancreatic tumor stroma could be a potential therapeutic target to increase Ccl20 secretion from TAF and induce accumulation of CD8+ T cells, which would be expected to enhance antitumor immunity.

Case of a tumor comprising gastric cancer and duodenal neuroendocrine tumor

The present report describes a rare case of a tumor composed of early gastric cancer and a duodenal neuroendocrine tumor (NET). A 78-year-old woman underwent esophagogastroduodenoscopy at a local institution for screening of the upper gastrointestinal tract which revealed a protruded tumor through the pyloric ring from the pyloric antrum. The tumor was too large to treat at the facility; consequently, she was referred to our hospital for further management. Esophagogastroduodenoscopy with tumor biopsy of the lesion revealed the diagnosis of early gastric cancer. Endoscopic submucosal dissection was performed with sufficient free margins in both vertical and horizontal directions. Histopathological findings showed NET confined to the submucosal layer and covered by well-differentiated adenocarcinoma. Immunohistochemical stainings showed that the two lesions existed continuously. While the possibility of a collision cancer was considered, it was suggested that the two lesions existed continuously. Finally, the tumor was diagnosed as gastric cancer composed of duodenal NET G1, with a lymphatic invasion of NET component.