Search

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

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

Introduction and aimsThis international survey was performed to evaluate the cumulative incidence of nosocomial novel coronavirus disease 2019 (COVID-19) among healthcare professionals during endoscopic procedures.MethodsWe performed an international web-based self-reported questionnaire survey. Participants completed the questionnaires every week for 12 weeks. The questionnaire elicited responses regarding the development of COVID-19 and details of the PPE used.ResultsAll 483 participants were included in the analysis. Participants had a mean age of 42.3 years and comprised 68.3% males. The geographic distribution of the study population was Asia (89.2%), Europe (2.9%), North and South America (4.8%), Oceania (0.6%), and Africa (1.5%). The most common endoscopy-related role of the participants was endoscopist (78.7%), and 74.5% had > 10 years of experience. Fourteen participants had performed 83 endoscopic procedures in patients positive for COVID-19. During the mean follow-up period of 4.95 weeks, there were no cases of COVID-19 when treating COVID-19 positive patients. The most common PPE used by participants treating patients with COVID-19 was a surgical mask plus N95 mask plus face shield, goggles, cap, long-sleeved isolation gown, and single pair of gloves. The most common PPE used by participants treating patients without COVID-19 was a surgical mask, no face shield but goggles, cap, long-sleeved isolation gown, and single pair of gloves during all endoscopic procedures.ConclusionsThe risk of COVID-19 transmission during any endoscopic procedure was low in clinical practice.

Background and Aim A number of recent studies have been published evaluating the chemopreventive effect of aspirin against gastric cancer, and an updated meta‐analysis is required to evaluate this relationship further. This study presents a meta‐analysis of studies examining the effect of aspirin on gastric cancer incidence and death. Methods The PUBMED and Cochrane Central Registration of Controlled Trials databases were searched for eligible studies published up to December 2018. Pooled risk ratios for gastric cancer incidence and death in aspirin users versus nonusers were determined using fixed‐ and random‐effects models. The influence of the frequency of aspirin use, duration of aspirin use, and geographic location on gastric cancer incidence was evaluated. Results The meta‐analysis comprised 33 studies with a total of 1 927 971 patients. The pooled risk ratios for gastric cancer incidence in the fixed‐ and random‐effects models were 0.890 (95% confidence interval, 0.871–0.909) and 0.826 (0.740–0.922), respectively. In Asia and North America, the maximum preventive benefit of aspirin use was observed with weekly or daily use. Aspirin use was most effective for noncardiac gastric cancer. The pooled risk ratios for gastric cancer death in the fixed‐ and random‐effects models were 0.798 (0.749–0.850) and 0.894 (0.780–1.024), respectively. Significant heterogeneity was observed among studies of gastric cancer incidence but not gastric cancer death. Conclusion Aspirin use may reduce the risk of gastric cancer incidence and death; however, the relationship may be limited to a specific frequency and duration of aspirin use and geographic location., A number of recent studies have been published evaluating the chemopreventive effect of aspirin against gastric cancer, and an updated meta‐analysis is required to evaluate this relationship further. Of 463 studies, we analyzed 33 studies with a total of 1 927 971 patients. The pooled risk ratios for gastric cancer incidence were 0.890 (95% confidence interval, 0.871–0.909) and 0.826 (0.740–0.922) in the fixed‐ and random‐effects models, respectively. The pooled risk ratios for gastric cancer death in the fixed‐ and random‐effects models were 0.798 (0.749–0.850) and 0.894 (0.780–1.024), respectively. Aspirin use may reduce the risk of gastric cancer incidence and death.

Defining tumor cell immune evasion Mouse models used to study cancer often lack a full immune system, allowing implantation of human tumors into the mice. By contrast, naturally evolving tumors must contend with a fully functional immune system and its destruction of some of the cells (see the Perspective by Ho and Wood). Two groups now report studies on mouse models with a fully intact immune system. Martin et al . started with preexisting murine tumor cell lines and examined their continued evolution in vivo, whereas Del Poggetto et al . examined the development of new pancreatic tumors in the context of inflammation, as is often seen in human patients. In each study, the authors found that the immune system exerted a selective pressure on cells that would give rise to tumors, promoting the survival of those that had lost expression of tumor suppressor genes or activated a specific oncogene. The findings suggest a major role for the immune system in driving tumor evolution across multiple types of cancer. —YN

We read with great interest the recent publication written by Lee et al 1 in which the authors conducted a prospective, longitudinal and multicentre study to evaluate the association between intestinal metaplasia (IM) and gastric cancer (GC). As expected, IM was found to be a significant risk factor for GC (adjusted HR (aHR) 5.46; 95% CI 1.51 to 19.0). Nevertheless, operative link on gastric IM (OLGIM) staging was more closely correlated with the risk of GC (stage III/IV; aHR 20.7; 95% CI 5.04 to 85.6, and stage II; aHR 7.34; 95% CI 1.60 to 33.7). They concluded that risk stratification of GC based on OLGIM staging was useful for endoscopic surveillance. We agree with their results that OLGIM staging is the most important predictor for GC, although there are many other risk factors of GC. According …

A retrospective case–controlled analysis was performed to identify drug candidates in the current use that may prevent colorectal cancer, outside of aspirin. A total of 37,510 patients aged ≥20 years were assessed to identify subjects who had been diagnosed with colorectal cancer by colonoscopy without a previous diagnosis of colorectal cancer, inflammatory bowel disease (IBD), or gastrointestinal symptoms; 1,560 patients were identified who were diagnosed with colorectal cancer by colonoscopy. The patients with colorectal cancer were matched with 1,560 age, gender, family history of colorectal cancer and comorbidity-matched control patients who were not diagnosed with colorectal cancer at colonoscopy. The medication histories were compared between the two groups. Next, candidate drugs that were more frequently used by the control patients were selected and their effects on human colorectal cancer cell lines in vitro and an inflammation-induced mouse model of colorectal cancer were tested. Putative colorectal cancer preventative agents were identified, including aspirin, vitamin D, vitamin B, vitamin C, vitamin E, xanthine oxidase inhibitor, alpha-blockers, angiotensin receptor blocker, nateglinide, probiotics, thienopyridine, folic acid, nitrovasodilators, bisphosphonates, calcium channel blockers, steroids, and statins (P < 0.05). Alpha-blockers and xanthine oxidase inhibitors were selected for further study because these agents have not been analyzed previously as factors that may affect colorectal cancer outcomes. In vitro doxazosin (alpha-blocker), but not febuxostat (xanthine oxidase inhibitor), suppressed the proliferation of human colorectal cancer cells. Doxazosin also decreased tumorigenesis in an AOM/DSS mouse colorectal cancer model. Alpha-blockers may prevent colorectal cancer.

Background A small proportion of Helicobacter pylori-infected individuals in Japan suffer failure of eradication therapy with third-line regimens containing the potent acid suppressor, vonoprazan, and a quinolone. Objectives This prospective study evaluated the efficacy and safety of rifabutin-based triple therapy with vonoprazan for refractory H pylori infection. Methods Patients who failed H pylori eradication by clarithromycin-based first-line, metronidazole-based second-line, and sitafloxacin-based third-line therapies were recruited. After obtaining informed consent, patients received eradication therapy with vonoprazan (20 mg), amoxicillin (750 mg), and rifabutin (150 mg) twice daily for 10 days. Eradication was confirmed by a negative H pylori stool antigen or urea breath test at least 8 weeks after the end of therapy. Results Nineteen patients were included in the study. All of the patients completed the course of medication. Eradication of H pylori was confirmed in all of the patients (19/19; 100%, 95% confidence interval; 83-100%). The most common adverse event was soft stool/diarrhea (4/19, 21%). No severe adverse event was observed. Conclusions Ten-day rifabutin with amoxicillin and vonoprazan triple therapy appears to be effective and safe for refractory H pylori infections. However, considering the recent publications showing high eradication rates with vonoprazan amoxicillin dual therapy, confirmation will require future studies comparing our new therapy with vonoprazan-amoxicillin dual with similar doses and duration and with vonoprazan-rifabutin dual therapy.

During human gastric carcinogenesis, intestinal metaplasia is frequently seen in the atrophic stomach. In mice, a distinct type of metaplasia known as spasmolytic polypeptide-expressing metaplasia (SPEM) is found in several inflammatory and genetically engineered models. Given the diversity of long- and short-term models of mouse SPEM, it remains unclear whether all models have a shared or distinct molecular mechanism. The origin of SPEM in mice is presently under debate. It is postulated that stem or progenitor cells acquire genetic alterations that then supply metaplastic cell clones, whereas the possibility of transdifferentiation or dedifferentiation from mature gastric chief cells has also been suggested. In this study, we report that loss of chief cells was sufficient to induce short-term regenerative SPEM-like lesions that originated from chief cell precursors in the gastric neck region. Furthermore, Lgr5+ mature chief cells failed to contribute to both short- and long-term metaplasia, whereas isthmus stem and progenitor cells efficiently contributed to long-term metaplasia. Interestingly, multiple administrations of high-dose pulsed tamoxifen induced expansion of Lgr5 expression and Lgr5-CreERT recombination within the isthmus progenitors apart from basal chief cells. Thus we conclude that short-term SPEM represents a regenerative process arising from neck progenitors following chief cell loss, whereas true long-term SPEM originates from isthmus progenitors. Mature gastric chief cells may be dispensable for SPEM development. NEW & NOTEWORTHY Recently, dedifferentiation ability in gastric chief cells during metaplasia development has been proposed. Our findings reveal that lesions that were thought to be acute metaplasia in fact represent normal regeneration supplied from neck lineage and that isthmus stem/progenitors are more responsible for sustained metaplastic changes. Cellular plasticity in gastric chief cells may be more limited than recently highlighted.

Background and Aim Histological gastritis is associated with gastric cancer, but its diagnosis requires biopsy. Many classifications of endoscopic gastritis are available, but not all are useful for risk stratification of gastric cancer. The Kyoto Classification of Gastritis was proposed at the 85th Congress of the Japan Gastroenterological Endoscopy Society. This cross-sectional study evaluated the usefulness of the Kyoto Classification of Gastritis for risk stratification of gastric cancer. Methods From August 2013 to September 2014, esophagogastroduodenoscopy was performed and the gastric findings evaluated according to the Kyoto Classification of Gastritis in a total of 4062 patients. The following five endoscopic findings were selected based on previous reports: atrophy, intestinal metaplasia, enlarged folds, nodularity, and diffuse redness. Results A total of 3392 patients (1746 [51%] men and 1646 [49%] women) were analyzed. Among them, 107 gastric cancers were diagnosed. Atrophy was found in 2585 (78%) and intestinal metaplasia in 924 (27%). Enlarged folds, nodularity, and diffuse redness were found in 197 (5.8%), 22 (0.6%), and 573 (17%), respectively. In univariate analyses, the severity of atrophy, intestinal metaplasia, diffuse redness, age, and male sex were associated with gastric cancer. In a multivariate analysis, atrophy and male sex were found to be independent risk factors. Younger age and severe atrophy were determined to be associated with diffuse-type gastric cancer. Conclusion Endoscopic detection of atrophy was associated with the risk of gastric cancer. Thus, patients with severe atrophy should be examined carefully and may require intensive follow-up.

Gastrin was initially identified as the hormone primarily responsible for gastric acid secretion, but was subsequently shown to be a growth factor for the proximal stomach, acting through the gastrin receptor CCK2R. Studies in the past several decades have explored the role of gastrin, along with its incompletely processed precursors, in cancer development. The growth in long-term PPI use has frequently led to elevations in serum gastrin levels in patients with upper GI disease, including GERD, peptic ulcers, and chronic gastritis. However, while accumulated evidence has shown that gastrin likely does not promote-and may even suppress-distal antral gastric cancer, questions have now arisen regarding possible effects of gastrin on the development of gastric cardia cancer or esophageal adenocarcinoma at gastroesophageal junction. Here, we provide an overview of the possible roles of these gastrin peptides in upper GI cancer.

Vagotomy reduces gastric acid secretion and was therefore introduced as a surgical treatment for peptic ulcers in the 1970s. Later, it was replaced by acid reducing medication, such as histamine type 2 (H2) receptor antagonists and proton pump inhibitors (PPIs). A large body of evidence has indicated that drug-induced hypochlorhydria per se does not increase the risk of gastric cancer. Early studies on the effects of vagotomy in chemically-induced rodent models of gastric cancer reported an increased risk of developing gastric cancer. This was most likely due to a delayed gastric emptying, which later has been accounted for by including an additional drainage procedure, e.g. pyloroplasty. In a recent study using three different mouse models of gastric cancer (including genetically engineered, chemically-induced and Helicobacter pylori-infected mice), either unilateral vagotomy or bilateral truncal vagotomy with pyloroplasty was found to significantly attenuate tumorigenesis in the denervated side of the stomach at early preneoplastic stages as well as at later stages of tumorigenesis. Consistently, pharmacological denervation using botulinum toxin A or muscarinic acetylcholine receptor 3 (M3R) blockade inhibited tumorigenesis. Moreover, it was found that recurrence of gastric cancer was reduced in patients following vagotomy. Thus, these new findings suggest the potential treatment strategies to target the nerve, neurotransmitters, corresponding receptors and their downstream signaling pathways for the malignancy. Copyright © 2016 Bentham Science. This is the authors' manuscript to the article. Preprint.

Objective Vonoprazan is a potassium-competitive acid blocker, a new type of acid-suppressing drug, and has recently become available for peptic ulcers, gastroesophageal reflux disease, and Helicobacter pylori (H. pylori) eradication. Its efficacy for H. pylori eradication has been reported. However, the evidence for its efficacy and feasibility remains limited. We aimed to compare the feasibility, effectiveness and safety of vonoprazan-based triple therapy with conventional proton pump inhibitor (PPI)-based triple therapy in multicenter clinical practice. Methods We performed a multicenter retrospective study on patients receiving first-line H. pylori eradication therapy between March 2013 and November 2015 with either vonoprazan-based triple therapy or conventional PPI-based triple therapy. Results A total of 2715 patients aged 63.0 ± 12.1 years (1412 [52.0%] males) were analyzed. Eradication rates were 87.2% (368/422) for vonoprazan-based therapy and 72.4% (1661/2293) for conventional PPI-based therapy (P Conclusion Vonoprazan-based triple therapy is feasible, and has a higher rate for H. pylori eradication than conventional PPI as a first-line regimen.

Background and Aims Helicobacter pylori eradication therapy is effective at reducing the incidence of gastric cancer; however, gastric cancer still develops after eradication. We conducted a cohort study to elucidate the risk factors for gastric cancer development after successful H pylori eradication therapy. Methods From June 1998 to December 2012 we assessed histologic and endoscopic findings of gastritis and performed H pylori eradication therapy in 748 patients without a history of gastric cancer. Patients were classified according to the distribution of intestinal metaplasia (IM) as follows: no IM (IM group A), IM in the antrum only (IM group B), and IM in the corpus (IM group C). We assessed atrophy endoscopically according to the Kimura-Takemoto classification system. Gastric cancer incidence was assessed. Results A total of 573 patients underwent follow-up endoscopy; the mean duration of follow-up was 6.2 ± 4.8 years. Gastric cancer developed in 21 (20 intestinal type). The cumulative 5-year incidences of gastric cancer were 3.2% overall; 1.5%, 5.3%, and 9.8% in IM groups A, B, and C; and 0.7%, 1.9%, and 10% in the none/mild, moderate, and severe endoscopic atrophy groups, respectively. Compared with IM group A, the hazard ratio for IM group B was 3.6 (95% confidence interval [CI], 1.2-11), and that for IM group C was 3.7 (95% CI, 1.1-12). Compared with the none/mild endoscopic atrophy group, the hazard ratio for severe atrophy was 9.3 (95% CI, 1.7-174). Conclusions Patients with histologic IM or severe endoscopic atrophy were at increased risk of gastric cancer development after H pylori eradication.

Cancers of the gastrointestinal (GI) tract are among the most frequent and most lethal cancers worldwide. An important reason for this high mortality is that early disease is typically asymptomatic, and patients often present with advanced, incurable disease. Even in high-risk patients who routinely undergo endoscopic screening, lesions can be missed due to their small size or subtle appearance. Thus, current imaging approaches lack the sensitivity and specificity to accurately detect incipient GI tract cancers. Here we report our finding that a single dose of a high-sensitivity surface-enhanced resonance Raman scattering nanoparticle (SERRS-NP) enables reliable detection of precancerous GI lesions in animal models that closely mimic disease development in humans. Some of these animal models have not been used previously to evaluate imaging probes for early cancer detection. The studies were performed using a commercial Raman imaging system, a newly developed mouse Raman endoscope, and finally a clinically applicable Raman endoscope for larger animal studies. We show that this SERRS-NP-based approach enables robust detection of small, premalignant lesions in animal models that faithfully recapitulate human esophageal, gastric, and colorectal tumorigenesis. This method holds promise for much earlier detection of GI cancers than currently possible and could lead therefore to marked reduction of morbidity and mortality of these tumor types.

We read with interest the recent publication by Cheung et al . The authors conclude that proton pump inhibitor (PPI) use is associated with a 2.4-fold increase in the risk of gastric cancer in patients who received Helicobacter pylori eradication therapy.1 This is an important finding given that the safety of long-term PPI use remains unclear. Notably, no significant association between histamine-2 receptor antagonist (H2RA) use and gastric cancer was observed, which suggests a PPI-specific effect in this context. Cheung et al used a large population-based database to select patients after eradication and performed propensity score adjustment analysis. However, as the authors described in the Discussion section, we have concerns about the limitations of this study, in particular the lack of endoscopic and histological examinations, the results of which could influence the association between PPI use and gastric cancer. The presence …

In Asia, the incidences of Helicobacter pylori infection and gastric cancer are high, but their association with autoimmune gastritis (AIG) is unclear. This was a retrospective cohort study of patients endoscopically diagnosed with chronic gastritis between 2005 and 2017. AIG was diagnosed according to anti-parietal cell antibody positivity. Laboratory, histological findings, and gastric cancer incidence were compared between AIG and non-AIG patients. The AIG group had more females and a higher rate of thyroid disease. Serum levels of gastrin were significantly higher in AIG patients (mean 1412 and 353 pg/mL, p &lt, 0.001). The endoscopic findings included a significantly higher percentage of corpus-dominant atrophy in AIG (31.67%) than in non-AIG (7.04%) patients (p &lt, 0.001). Clusters of ECL cells were observed in 28% of AIG patients and 7% of non-AIG patients (p = 0.032). The cumulative incidence of gastric cancer at 5 and 10 years was 0% and 0.03% in the AIG group and 0.03% and 0.05% in the non-AIG group, and no significant difference in gastric cancer incidence was observed. Despite significant differences in gastrin levels between AIG and non-AIG patients, there was no evidence of an impact of AIG on the incidence of gastric cancer.

// Yoomi Lee 1, * , Aleksandra M. Urbanska 2, * , Yoku Hayakawa 2 , Hongshan Wang 2, 3 , Andrew S. Au 2 , Aesis M. Luna 4 , Wenju Chang 2, 3 , Guangchun Jin 2 , Govind Bhagat 4 , Julian A. Abrams 2 , Richard A. Friedman 5, 6 , Andrea Varro 7 , Kenneth K. Wang 8 , Malcolm Boyce 9 , Anil K. Rustgi 10 , Antonia R. Sepulveda 4 , Michael Quante 11 , Timothy C. Wang 2 1 Division of Hematology and Oncology, Department of Medicine, Columbia University Medical Center, New York, NY, USA 2 Division of Digestive and Liver Diseases, Department of Medicine, Columbia University Medical Center, New York, NY, USA 3 Department of General Surgery, Zhongshan Hospital, Fudan University, Shanghai, China 4 Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, USA 5 Biomedical Informatics Shared Resource, Herbert Irving Comprehensive Cancer Center, New York, NY, USA 6 Department of Biomedical Informatics, Columbia University Medical Center, New York, NY, USA 7 Department of Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, England 8 Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, USA 9 Hammersmith Medicines Research, Central Middlesex Hospital, London, UK 10 Division of Gastroenterology, Departments of Medicine and Genetics, Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA 11 Medical Clinic II, Clinic of the Right Bank, Technical University of Munich, Munich, Germany * These authors contributed equally to this work Correspondence to: Timothy C. Wang, email: tcw21@columbia.edu Keywords: Barrett’s esophagus, esophageal cancer, gastrin, gastrin receptors, stem cells Received: March 15, 2016 Accepted: June 13, 2016 Published: July 18, 2016 ABSTRACT Objective: The incidence of esophageal adenocarcinoma (EAC) is increasing, but factors contributing to malignant progression of its precursor lesion, Barrett’s esophagus (BE), have not been defined. Hypergastrinemia caused by long-term use of proton pump inhibitors (PPIs), has been suggested as one possible risk factor. The gastrin receptor, CCK2R, is expressed in the cardia and upregulated in BE, suggesting the involvement of the gastrin-CCK2R pathway in progression. In the L2-IL-1β mouse model, Barrett’s-like esophagus arises from the gastric cardia. Therefore, we aimed to analyze the effect of hypergastrinemia on CCK2R+ progenitor cells in L2-IL-1β mice. Design: L2-IL-1β mice were mated with hypergastrinemic ( INS-GAS ) mice or treated with PPIs to examine the effect of hypergastrinemia in BE progression. CCK2R-CreERT crossed with L2-IL-1β mice were used to analyze the lineage progenitor potential of CCK2R+ cells. Cardia glands were cultured in vitro , and the effect of gastrin treatment analyzed. L2-IL-1β mice were treated with a CCK2R antagonist YF476 as a potential chemopreventive drug. Results: Hypergastrinemia resulted in increased proliferation and expansion of Barrett’s-like esophagus. Lineage tracing experiments revealed that CCK2R+ cells are long-lived progenitors that can give rise to such lesions under chronic inflammation. Gastrin stimulated organoid growth in cardia culture, while CCK2R inhibition prevented Barrett’s-like esophagus and dysplasia. Conclusions: Our data suggest a progression model for BE to EAC in which CCK2R+ progenitor cells, stimulated by hypergastrinemia, proliferate to give rise to metaplasia and dysplasia. Hypergastrinemia can result from PPI use, and the effects of hypergastrinemia in human BE should be studied further.

Cancer-associated fibroblasts (CAFs) are a major constituent of the tumor microenvironment and play a critical part in cancer progression. However, the precise origin of the tumor stroma remains unknown, making it challenging to effectively target the cancer mesenchyme. Here, employing 4 different genetic fate mapping mouse models and a bone marrow transplantation model in combination with BrdU labeling, we uncovered a key contributor to the tumor stroma in colorectal cancer (CRC). We found that approximately half of a-smooth muscle actin (aSMA)+ CAFs emerge through proliferation in an AOM/DSS mouse model of CRC. Lineage tracing experiments revealed that intestinal leptin receptor (Lepr)-lineage stromal cells expanded and contributed to 75% of the aSMA+ proliferating CAFs. Notably, no aSMA+ CAFs in the tumor were derived from Krt19-lineage epithelial cells or bone marrow-transplanted cells, indicating no involvement of epithelial-mesenchymal transition and bone marrow recruitment to the tumor in this model. Moreover, RNA-sequencing of FACS-purified CRC mesenchymal cells identified MCAM (also known as CD146) as a CRC stroma-specific marker, which is expressed by Lepr-lineage cells. Analysis of human CRC samples showed that high MCAM expression was associated with a mesenchymal subtype of CRC and was independently prognostic of poor overall survival. Our data identify Lepr-lineage cells as a major source of the tumor stroma in CRC and suggest that targeting MCAM+ cells may serve as a novel therapeutic approach to restrain CRC progression. Citation Format: Hiroki Kobayashi, Krystyna A. Gieniec, Tamsin RM Lannagan, Tongtong Wang, Samuel Asfaha, Yoku Hayakawa, Simon J. Leedham, Nicholas Arpaia, Siddhartha Mukherjee, Timothy C. Wang, Atsushi Enomoto, Masahide Takahashi, Susan L. Woods, Daniel L. Worthley. The origin and contribution of the tumor stroma in colorectal cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5089.

Background and aims Disturbance of intestinal homeostasis is associated with the development of inflammatory bowel disease [IBD], and TGF-β signalling impairment in mononuclear phagocytes [MPs] causes murine colitis with goblet cell depletion. Here, we examined an organoid-MP co-culture system to study the role of MPs in intestinal epithelial differentiation and homeostasis. Methods Intestinal organoids were co-cultured with lamina propria leukocytes and bone marrow-derived dendritic cells [BMDCs] from CD11c-cre Tgfbr2fl/fl mice. Organoid-MP adhesive interactions were evaluated by microscopy, RT-PCR, and flow cytometry. Murine colitis models (dextran sodium sulphate [DSS], CD11c-cre Tgfbr2fl/fl, T-cell-transfer) were used for histological and immunohistochemical analysis. Anti-E-cadherin antibody treatment or CD11c+-cell-specific CDH1 gene deletion were performed for E-cadherin neutralization or knockout. Colonic biopsies from patients with ulcerative colitis were analysed by flow cytometry. Results Intestinal organoids co-cultured with CD11c+ lamina propria leukocytes or BMDCs from CD11c-cre Tgfbr2fl/fl mice showed morphological changes and goblet cell depletion with Notch signal activation, analogous to CD11c-cre Tgfbr2fl/fl colitis. E-cadherin was upregulated in CD11c+ MPs, especially CX3CR1+CCR2+ monocytes, of CD11c-cre Tgfbr2fl/fl mice. E-cadherin-mediated BMDC adhesion promoted Notch activation and cystic changes in organoids. Anti-E-cadherin antibody treatment attenuated colitis in CD11c-cre Tgfbr2fl/fl and T-cell-transferred mice. In addition, E-cadherin deletion in CD11c+ cells attenuated colitis in both CD11c-cre Tgfbr2fl/fl and DSS-treated mice. In patients with ulcerative colitis, E-cadherin expressed by intestinal CD11c+ leukocytes was enhanced compared with that in healthy controls. Conclusions E-cadherin-mediated MP-epithelium adhesion is associated with the development of colitis, and blocking these adhesions may have therapeutic potential for IBD.

Objective Clinically, patients with proton pomp inhibitor (PPI)-resistant gastroesophageal reflux disease (GERD) are very challenging to treat. The aim of this study was to determine the rates of symptom relief and adverse events among PPI-resistant GERD patients that changed their therapy from a PPI to vonoprazan. Methods Patients with severe gastroesophageal reflux symptoms (total GERD-Q score ≥8) without endoscopic findings of mucosal breaks who changed their medication from a PPI to vonoprazan during a 12-week period from 2015 to 2016 at 2 hospitals were selected. The primary outcome was the self-reported relief of gastroesophageal reflux symptoms. The odds ratio (OR) for the improvement of symptoms was calculated based on an exact binomial distribution using a matched-pair analysis. The secondary outcome was the GERD-Q score and adverse events. Results Twenty-six patients (6 men) with a mean age of 67.5 years were analyzed. After the therapy was changed from a PPI to vonoprazan, 18 patients (69.2%) reported an improvement, 6 (23.1%) reported no change, and 2 (7.7%) reported an exacerbation of symptoms. A change in therapy was significantly associated with improved self-reported symptoms (OR 9.0, p

Introduction: Although aspirin/NSAIDs may have potential preventive effects on several cancers, it remains unclear on gastric cancer. The purpose of this study is to compare the risk of developing gastric cancer and the histologic changes of intestinal metaplasia and neutrophil infiltration, between aspirin/NSAID users and nonusers. Methods: Using an electronic endoscopy database in two hospitals from 1996 to 2017, we analyzed the data from patients with chronic gastritis who received aspirin or NSAIDs prior to upper gastrointestinal endoscopy. One-to-one propensity score matching was performed to compare the proportion of gastric cancer, intestinal metaplasia, and neutrophil infiltration between these drug users and nonusers. Results: We analyzed 2,082 aspirin users and 2,082 nonusers as well as 898 NSAID users and 898 nonusers. Six diffuse-type and 19 intestinal-type gastric cancer, 1,243 intestinal metaplasia, and 1,503 neutrophil infiltration patients were identified. The proportion of diffuse-type gastric cancer (0.05%) was 80% lower in aspirin users compared with the nonusers (0.24%), and there was no case of diffuse-type cancer in patients who took aspirin for more than 2 years. In contrast, intestinal-type gastric cancer incidence was significantly higher in aspirin users (0.72%) compared with nonusers (0.14%). No significant differences in the incidence of gastric cancer were found between NSAID use and nonusers. NSAID use was significantly associated with decreased proportion of neutrophil infiltration compared with nonusers. Conclusion: Aspirin may have distinct effects between intestinal-type and diffuse-type gastric cancer development. Cancer Prev Res; 11(5); 279–86. ©2018 AACR.

Background There are limited colonoscopy-based cohort data concerning the effectiveness of colonoscopy in reducing colorectal cancer deaths. The aim of this study was to clarify whether colonoscopy reduces colorectal cancer mortality. Methods A cohort of 18,816 patients who underwent colonoscopy without a diagnosis of colorectal cancer between 2001 and 2010 at high colonoscopy procedure volume centers was selected. Patient characteristics and colonoscopy findings were assessed. The main endpoint was colorectal cancer death (all, right-sided, and left-sided cancers), and data were censored at the time of the final visit or the final colonoscopy. The standardized all colorectal, colon, and rectal cancer mortality rates were estimated with reference to those of the general Japanese population. Additional outcome was all- cause death and the standardized all-cause mortality rate was also estimated. Results The total observed person-year mortality for colorectal cancer was 67,119. Of these, 4, 3, and 1 patients died from colorectal, colon, and rectal cancers, respectively; these values were significantly lower than the number of expected deaths in the general population, estimated to be 53.1, 34.0, and 19.1, respectively. The standardized mortalities for all colorectal, colon, and rectal cancers were 0.08 (95% confidence interval (CI), 0.02–0.17), 0.09 (95% CI, 0.02–0.22), and 0.05 (95% CI, 0.0002–0.21), respectively. There were 586 all-cause deaths (3.11%) during the observation period. The standardized all-cause mortality ratios were 0.22 (95% CI, 0.206–0.23). Conclusions The colorectal cancer mortality of patients who received colonoscopy without colorectal cancer diagnosis decreased significantly compared with that of individuals in the general population. These results were compatible even in patients with right-sided colon cancer.

Background: Helicobacter pylori (H. pylori) eradication therapy may improve gastric atrophy and intestinal metaplasia, but the results of previous studies have not always been consistent. The aim of this study was to compare the histological changes of intestinal metaplasia and gastric atrophy among the use of acid-suppressing drugs after H. pylori eradication. Methods: A cohort of 242 patients who underwent successful eradication therapy for H. pylori gastritis and surveillance endoscopy examination from 1996 to 2015 was analyzed. Changes in the histological scores of intestinal metaplasia and atrophy according to drug use (proton-pump inhibitors (PPIs), H2 receptor antagonists (H2RAs), and non-acid suppressant use) were evaluated in biopsies of the antrum and corpus using a generalized linear mixed model in all patients. Results: The mean follow-up period and number of biopsies were 5.48 &plusmn, 4.69 years and 2.62 &plusmn, 1.67 times, respectively. Improvement in the atrophy scores of both the antrum (p = 0.042) and corpus (p = 0.020) were significantly superior in patients with non-acid suppressant drug use compared with those of PPI and H2RA use. Metaplasia scores in both the antrum and corpus did not improve in all groups, and no significant differences were observed among groups in the antrum (p = 0.271) and corpus (p = 0.077). Conclusions: Prolonged acid suppression by PPIs or H2RAs may limit the recovery of gastric atrophy following H. pylori eradication.

Although some molecularly targeted drugs for colorectal cancer are used clinically and contribute to a better prognosis, the current median survival of advanced colorectal cancer patients is not sufficient. Autophagy, a basic cell survival mechanism mediated by recycling of cellular amino acids, plays an important role in cancer. Recently, autophagy has been highlighted as a promising new molecular target. The unfolded protein response (UPR) reportedly act in complementary fashion with autophagy in intestinal homeostasis. However, the roles of UPR in colon cancer under autophagic inhibition remain to be elucidated. We aim to clarify the inhibitory effect of autophagy on colon cancer. We crossed K19 CreERT and Atg5 flox/flox mice to generate Atg5 flox/flox /K19 CreERT mice. Atg5 flox/flox /K19 CreERT mice were first treated with azoxymethane/dextran sodium sulfate and then injected with tamoxifen to inhibit autophagy in CK19-positive epithelial cells. To examine the anti-cancer mechanisms of autophagic inhibition, we used colon cancer cell lines harboring different p53 gene statuses, as well as small interfering RNAs (siRNAs) targeting Atg5 and immunoglobulin heavy-chain binding protein (BiP), a chaperone to aid folding of unfolded proteins. Colon tumors in Atg5 flox/flox /K19 CreERT mice showed loss of autophagic activity and decreased tumor size (the total tumor diameter was 28.1 mm in the control and 20.7 mm in Atg5 flox/flox /K19 CreERT mice, p = 0.036). We found that p53 and UPR/endoplasmic reticulum (ER) stress-related proteins, such as cleaved caspase 3, and CAAT/enhancer-binding protein homologous protein, are up-regulated in colon tumors of Atg5 flox/flox /K19 CreERT mice. Although Atg5 and BiP silencing, respectively, increased apoptosis in p53 wild type cells, Atg5 silencing alone did not show the same effect on apoptosis in p53 mutant cells. However, co-transfection of Atg5 and BiP siRNAs led to increased apoptosis in p53 mutant cells. Blocking autophagy has potential in the treatment of colon cancer by inducing apoptosis via p53 and ER stress, and suppressing the UPR pathway is a valid strategy to overcome resistance to autophagic inhibition.

Catecholamines stimulate epithelial proliferation, but the role of sympathetic nerve signaling in pancreatic ductal adenocarcinoma (PDAC) is poorly understood. Catecholamines promoted ADRB2-dependent PDAC development, nerve growth factor (NGF) secretion, and pancreatic nerve density. Pancreatic Ngf overexpression accelerated tumor development in LSL-Kras+/G12D;Pdx1-Cre (KC) mice. ADRB2 blockade together with gemcitabine reduced NGF expression and nerve density, and increased survival of LSL-Kras+/G12D;LSL-Trp53+/R172H;Pdx1-Cre (KPC) mice. Therapy with a Trk inhibitor together with gemcitabine also increased survival of KPC mice. Analysis of PDAC patient cohorts revealed a correlation between brain-derived neurotrophic factor (BDNF) expression, nerve density, and increased survival of patients on nonselective β-blockers. These findings suggest that catecholamines drive a feedforward loop, whereby upregulation of neurotrophins increases sympathetic innervation and local norepinephrine accumulation. Renz et al. show that catecholamines promote ADRB2-dependent pancreatic ductal adenocarcinoma development and secretion of neurotrophins (NT), which in turn promote tumor innervation leading to increased NE and tumor growth. Blockade of ADRB2 or NT receptors improves gemcitabine's therapeutic effect.

Purpose: Nuclear factor κB (NF-κB) is an important transcription factor in various biological processes. Constitutive NF-κB activation has been noted in many tumors, including colorectal cancers. However, the precise role of this activation in colorectal cancer is unclear. Experimental Design: Constitutive NF-κB activation was evaluated in colorectal cancer tissues and cell lines. To inhibit NF-κB activation, we established cancer cells with stable knockdown of IκB kinase γ (NF-κB essential modulator), which is the regulatory subunit of the IκB kinase complex, by RNA interference. Cell growth and apoptosis were evaluated in wild-type cells (WT) and knocked-down cells (KD). Microarray and protein array analysis were also done. To determine involvement of angiogenesis, human umbilical vein endothelial cells were used. By s.c. transplantation of the cells into nude mice, tumor sizes, vascularity, and chemodrug sensitivity were analyzed. Results: Constitutive NF-κB activation was observed in 40% of colorectal cancer tissues and 67% of cell lines. Cell proliferation was not different between WT and KD in vitro, whereas apoptosis mediated by tumor necrosis factor-α and 5-fluorouracil were increased in KD. Several angiogenic chemokines were decreased in KD. Human umbilical vein endothelial cells incubated in WT supernatant showed more branch points than in KD, suggesting that constitutive NF-κB activation was involved in angiogenesis. Subcutaneous tumor expansion was suppressed to 23% in KD, and vessels were also decreased. By 5-fluoruracil treatment, tumor expansion was suppressed to a greater extent in KD (to 6%) than in WT (to 50%). Conclusion: NF-κB inhibition may represent a potent treatment modality in colorectal cancer, especially in cases with constitutive NF-κB activation.

Since advanced gastric cancer is difficult to cure with chemo and/or radiation therapy, new therapeutic approaches are clearly needed. Targeting immune checkpoints such as CTLA-4 and PD-1/PD-L1 has shown promising antitumor immunity in many malignancies by modulating T cell activity. PD-L1 and to a lesser extent of PD-L2 are expressed in human gastric cancer and expression of PD-L1 is associated with poor prognosis. Therefore, developing immunotherapies is an attractive strategy for the treatment of gastric cancer. We evaluated the efficacy of anti-PD-1 therapy in a mouse model of gastric cancer. Gastrin-deficient (GAS-KO) mice have been shown to develop large antral tumors with the combination of N-methyl-N-nitrosourea (MNU) and Helicobacter felis (H. felis) infection. Tumors developed in GAS-KO mice exhibited increased expression of PD-L1 and higher mutation rates than those in wild-type mice. To study the effect of anti-PD-1 antibody in tumor initiation or an early stage of progression, GAS-KO mice were induced with H.felis/MNU to develop tumors, one week later (10 weeks post-MNU) treated with anti-PD-1 antibody or isotype control (10 mg/kg IP qw) and sacrificed at 30 weeks post-MNU. We confirmed that GAS-KO mice treated with isotype control had moderate tumor burdens. Of interest, however, less and much smaller tumors were observed in mice treated with anti-PD-1. To compare immune cell populations in spleen tissue and peripheral blood from each group of mice, flow cytometric analysis was performed. Anti-PD-1-treated mice showed an increase in T cells including cytotoxic CD8+ T cells and a decrease in regulatory T cells and myeloid-derived suppressor cell (MDSC) populations compared with controls. In accordance with this, CD3-positive T lymphocytes were more frequently found in gastric tumors of anti-PD-1-treated mice than controls. Furthermore, qRT-PCR analysis revealed differential cytokine gene expression profiles including Il6, Il1b, and Il23 following anti-PD-1 treatment. Together, these data implicate that PD-1 blockade promotes immune infiltrates and therefore potentiates antitumor immune responses, suggesting targeting PD-1 as a potential new anticancer strategy in gastric cancer. Understanding anti-PD-1 therapy at the cellular and molecular level could provide new strategies for developing highly efficacious combination therapies. Citation Format: Woosook Kim, Yoku Hayakawa, James G. Fox, Timothy C. Wang. PD-1 blockade suppresses gastric cancer development by promoting antitumor immunity in mice. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2340.

Introduction and objectives: There is increasing evidence that chronic activation of sympathetic neurons can lead to increased noradrenaline levels in the tumor microenvironment (TME) in PDAC. However, the mechanisms by which adrenergic neurotransmitters are delivered to the TME are not well understood. In this study we aimed to investigate the effect of locally and systemically delivered catecholamines into the TME in two well established genetically engineered mouse models of PDAC (Pdx1-Cre/KRasG12D (KC) and Pdx1-Cre/KRasG12D/Trp53R172H (KPC)). Methods: Adrenergic signaling was induced or inhibited in KC or KPC mice and in pancreatic organoids using various pharmacological compounds. Adrenergic receptor expression was assessed by RT-PCR, WB and IHC. Downstream pathways were identified by phosphorylation assays and WB. Adrenergic signaling was modeled in vivo applying restraint stress. To elucidate the crosstalk between nerves and cancer cells, pancreatic spheres and PDAC cells were co-cultured with DRGs and neuronal plasticity was quantified. NGF secretion was measured by RT-PCR and ELISA. Sympathetic denervation of the pancreas and blockage of the 2-receptor was employed as a treatment strategy in KPC mice. Overexpression of NGF was targeted to the mouse pancreas using a novel NGF knockin mouse, which was crossed to KC and KPC mice. Results: ADRB2 was upregulated during pancreatic cancer development. Furthermore, in vitro stimulation of cells harboring an oncogenic KRas mutation with catecholamines resulted in significantly increased sphere forming efficiency. The non-specific -blocker propranolol and the selective 2-blocker ICI 118,551 inhibited this effect. Selective blockade of 2-adrenergic signaling suppressed pancreatic sphere formation caused by co-cultures with DRGs. NGF secretion was stimulated through beta2-adrenergic signaling. Furthermore, restraint stress accelerated PDAC development in KC mice. The effects of stress were prevented by treatment with the selective ADRB2 antagonist ICI 118,551. Specific β2-blocker treatment as well as sympathetic denervation in addition to GEM significantly increased the survival of mice with 3-5 mm tumors in comparison to controls treated by GEM alone. Targeted overexpression of NGF in the mouse pancreas using a novel NGF knockin mouse resulted in marked acceleration of PanIN lesions in the KC mouse and shortened overall survival in KPC mice significantly. Finally, retrospective analysis of a PDAC patient cohort revealed a extension of overall survival in PDAC patients on non-selective -blockers. Conclusions: Taken together, these studies suggest that increased catecholamines can engender a feed forward loop, whereby upregulation of NGF can lead to increased innervation and local NE accumulation, thereby enhancing tumor growth. Therapies targeting these adrenergic and NGF pathways may prove useful in the treatment and prevention of pancreatic cancer. Citation Format: Bernhard W. Renz, Marina Macchini, Yoku Hayakawa, Xiaowei Chen, Zhengyu Jiang, Takayuki Tanaka, C. Benedikt Westphalen, Yagnesh Tailor, Jens Werner, Axel Kleespies, Alina C. Iuga, Daniel L. Worthley, Kenneth P. Olive, Timothy C. Wang. A novel β 2 adrenergic-nerve growth factor feed forward loop promotes pancreatic cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5111.

The incidence of esophageal adenocarcinoma (EAC) has markedly increased in the United States over the last few decades. Barrett's esophagus (BE) is the most significant known risk factor for this malignancy. Barrett's metaplasia, a condition of esophagus characterized by a columnar-cell metaplasia that replaces the native squamous-cell epithelium is considered to be a complication of gastroesophageal reflux disease (GERD), another risk factor for EAC. The paradigm is that BE arises from an adaptation to the harsh intra-esophageal environment of chronic GERD, and predisposes to EAC. Other established risk factors for EAC include obesity, smoking, poor diet. Moreover, while BE patients often undergo periodic endoscopic examinations, screening for dysplasia has not been shown to decrease mortality and remains controversial. Thus, a better understanding of the risk factors for BE progression is needed. The precise role of CCK2R in the gastric cardia and Barrett's esophagus has not been defined. CCK2R is upregulated in the esophagus in human BE and EAC, and real-time PCR of BE tissues indicated that the level of expression was 2x higher than that in esophageal tissues from normal control patients. CCK2R is upregulated in the gastric cardia of mice with Barrett's metaplasia, and this effect is enhanced with administration of bile acids, a key component of the refluxate. In this study we used the L2-IL-1β model to determine whether CCK2R-expressing cells can give rise to BE, and whether inhibition of CCK2R could ameliorate the BE phenotype in our mouse model. In order to understand the role of CCK2R-expressing cells in normal cardia, we performed lineage tracing studies in CCK2R-CreERT mice. We generated CCK2R-CreERT/TdTomato mice and induced them with tamoxifen at 6 weeks of age. Single Tomato-red positive cells became visible at the base of the cardia at 24 hours after induction. By days 2, 3, and 5 these Tomato-red cells expanded and moved upward in the cardia gland in contiguous fashion until almost all the cells in the gland were labeled. Tomato-red cells persisted for as long as one year in the cardia. Thus, CCK2R labels a progenitor cell in the normal gastric cardia whose progeny populate the gland and persist for at least one year, suggesting the ability to self-renew and consistent with a cardia stem cell. Since CCK2R marks a proliferating progenitor cell in the cardia, we verified whether CCK2R also has functional importance in BE progression. We hypothesized that overexpression of gastrin, the ligand for CCK2R, could accelerate BE in L2-IL-1β mice. INS-GAS mice, which overexpress amidated gastrin under the transcriptional control of the insulin promoter, were crossed with L2-IL-1β mice. L2-IL-1β/INS-GAS mice treated with bile acids had significantly increased areas of BE involvement compared to L2-IL-1β or INS-GAS controls. No areas of BE were seen in wild type or INS-GAS mice treated with bile acids until the age of 12 months. Citation Format: Aleksandra M. Urbanska, Yoomi Lee, Yoku Hayakawa, Julian A. Abrams, Michael Quante, Timothy C. Wang. CCK2R marks a gastrin-responsive stem cell that gives rise to Barrett's esophagus. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1705.

The prognosis of unresectable advanced gastric cancer has improved over the last decade due to advances in chemotherapy. However, molecular targeting in gastric cancer therapy has been poorly established and the 5‑year survival rate is still

Nuclear factor kappaB (NF-kappaB) plays an important role in the regulation of innate immune responses, apoptosis, inflammation, and oncogenesis. NF-kappaB activation in the liver was observed after intrasplenic administration of a lung carcinoma cell line, LLC, which induces liver metastasis. To explore the role of Ikappa B kinase beta (IKKbeta), which is the critical kinase of the IKK complex, and NF-kappaB activation in metastasis, we injected LLC cells into hepatocyte-specific IKKbeta knockout mice (Ikkbeta(Deltahep)), whole-liver knockout (Ikkbeta(DeltaL+H)) mice, and control (Ikkbeta(F/F)) mice. Ikkbeta(DeltaL+H) mice developed liver metastasis with significantly lower liver weights and fewer metastatic foci compared to Ikkbeta(Deltahep) and Ikkbeta(F/F) mice. Furthermore, intrasplenic LLC injection induced the messenger RNA (mRNA) expression of interleukin (IL)-6 and IL-1beta in Ikkbeta(F/F) mice, whereas these genes were less expressed in Ikkbeta(DeltaL+H) mice. IL-6(-/-) mice and treatment with anti-IL-6 receptor antibody showed a lesser degree of metastatic tumor, indicating that IL-6 is associated with liver metastasis.Collectively, these observations suggest that IKKbeta/NF-kappaB activation controls the development of liver metastasis by way of IL-6 expression and is a potential target for the development of antimetastatic drugs.

Interleukin-6 (IL-6) may play a role in the pathogenesis of hepatocellular carcinoma (HCC). Recently, it was reported in mouse models that estrogen-mediated inhibition of IL-6 production explains the gender disparity in HCC. We conducted a retrospective cohort study to examine whether this hypothesis is applicable to human HCC. We enrolled 330 patients with chronic hepatitis C whose serum samples were collected between January 1994 and December 2002. Serum IL-6 concentrations were measured and patients were divided into three groups according to IL-6 levels: low, middle, and high. We evaluated the association between serum IL-6 levels and the risk of subsequent HCC development, including subgroup analysis on each gender. During the follow-up period (mean 9.0 yr), HCC developed in 126 patients. The incidence rates differed significantly among the three groups (p = 0.015), increasing in accordance with serum IL-6 levels. However, unexpectedly, this tendency was significant only in female patients. In a multivariate analysis, higher serum IL-6 level was an independent risk factor for HCC development in female patients, with a hazard ratio of 1.61. Although female patients showed a weak negative correlation between serum IL-6 levels and estradiol levels, the lower risk of HCC in female patients cannot be fully explained by estrogen-mediated inhibition of IL-6 production. In conclusion, higher serum IL-6 level was an independent risk factor for HCC development in female but not male chronic hepatitis C patients. Measurement of serum IL-6 levels may provide useful information for predicting future HCC development in female chronic hepatitis C patients.

Nuclear factor kappaB (NF-kappaB) activation is involved in various inflammatory illnesses, for example inflammatory bowel disease, and is thought to be a key factor in the tumor-promoting mechanism of inflammation-associated tumorigenesis. This study investigated whether inhibitors of IKKbeta, which is a critical kinase for NF-kappaB activation, reduce colitis-associated tumorigenesis in mice.We used a mouse model of the disease whereby administration of azoxymethane (AOM) followed by repeated dextran sulfate sodium (DSS) ingestion causes severe colonic inflammation and the subsequent development of multiple tumors. Effects of IKKbeta inhibitors, NBD peptide, and IMD-0354 were examined.In a colitis-associated cancer model, treatment with the IKKbeta inhibitors NBD peptide and IMD-0354 significantly reduced the number of tumors compared with the untreated group. The tumors were also significantly smaller in the inhibitor-treated mice than in the untreated mice. Macrophage and neutrophil infiltration decreased with the inhibitor treatment. NF-kappaB activation and the expression of Cox-2 and iNOS were observed in tumor tissues, and the inhibitors ameliorated their expression. These inhibitors blocked NF-kappaB activation and the expression of proinflammatory cytokines mediated by the culture supernatant of inflamed colon in murine primary macrophages. In-vitro and in-vivo experiments showed that these drugs, especially NBD peptide, could also inhibit the proliferation of colonic epithelial cells.These results imply that IKKbeta-targeted NF-kappaB blockade is an attractive therapeutic approach for the prevention of colitis-associated tumors.

Background/Aims: The parasympathetic nervous system plays an important role in the regulation of epithelial homeostasis and has also been postulated to play a role in tumorigenesis. However, the exact role of the vagus nerve in pancreatic carcinogenesis is not well understood. Here we study the effects of muscarinic signaling on pancreatic tumorigenesis in a genetically engineered mouse model of pancreatic cancer (PDx1-Cre/KRasG12D (KC). Methods: Mice were either vagotomized at 8 weeks or treated with a cholinergic agonist. Pancreatic tissue was collected and analyzed by immunohistochemistry and RT-PCR at 20 weeks of age; cells were isolated and assayed for colony and sphere forming assays. Different human (AsPC-1, BxPC-3, Mia PaCa-2, Panc-1) and murine (K-2548 and K-8282) pancreatic cancer cell lines were subjected to cholinergic and anti-cholinergic drugs and assayed by RT-PCR, Western blot and flow cytometry. Results: In pancreatic organoid cultures derived from pancreata harboring an oncogenic KRas mutation, cholinergic agonists suppressed sphere formation significantly. Furthermore, pharmacological inhibition or genetic knockout of the muscarinic M3 receptor abolished this effect in vitro. In human and murine pancreatic cancer cells, anchorage independent growth and tumor sphere forming capacity were reduced by pretreatment with cholinergic agonists. Further evaluation revealed that parasympathetic agonists decrease the CD44+CD24+EpCAM+ proved CSC's population. Vagotomy, when performed in KC mice at 8 weeks resulted in pancreatic cancer development in 20% of the animals at 20 week of age. Treatment with the direct muscarinic agonist bethanechol caused a significant delay of PanIN progression in KC mice. Conclusions: Taken together, our findings suggest that vagal innervation has a regulatory role in pancreatic tumorigenesis via M3 receptor-mediated suppression of CSCs. Since current surgical approaches to resection of PDAC from the head of the pancreas are necessarily associated with a parasympathetic denervation of the pancreas, and thereby a loss of its suppressive effect, this fact may might partly explain the high local recurrence rate of this dismal disease. Additional treatment with cholinergic agonists should be considered in future regimen. Citation Format: Bernhard W. Renz, Marina Macchini, Yoku Hayakawa, C. Benedikt Westphalen, Michael Churchill, Suchetak Kar, Xiaowei Chen, Karan Nagar, Yagnesh Tailor, Daniel L. Worthley, Alina C. Iuga, Ken P. Olive, Timothy C. Wang. Parasympathetic signaling suppresses pancreatic cancer development. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5079. doi:10.1158/1538-7445.AM2015-5079

Background/Aims: There is increasing evidence that chronic sympathetic nervous system activation can lead to increased noradrenaline levels in the tumor microenvironment. This process has been associated with proliferative signals largely mediated by beta-adrenergic signaling. However, the mechanisms by which adrenergic neurotransmitters are delivered to the tumor microenvironment are not well understood. In this study we aimed to investigate the role of locally and systemically delivered catecholamines to the tumor microenvironment in a well-established genetically engineered pancreatic cancer mouse model (PDx1-Cre/KRasG12D (KC) and PDx1-Cre/KRasG12D/Trp53R172H (KPC)). Methods: Adrenergic signaling was induced or inhibited in KC or KPC mice or 3D pancreatic spheres in culture using specific non-selective and selective agonists or antagonists. Adrenergic receptor expression was assessed by RT-PCR, Western blot and immunohistochemistry. Adrenergic signaling was also modeled in vivo applying restraint stress. To elucidate the crosstalk between nerve and cancer cells, pancreatic spheres and pancreatic cancer cells were co-cultured with dorsal root ganglia and neuronal plasticity was quantified by evaluating neurite outgrowth and number of branches. Denervation of the pancreas was performed using surgical or chemical neural ablation. Results: Adrenergic signaling receptors, in particular ADRB2, is upregulated during pancreatic cancer development. Furthermore, in vitro stimulation of cells harboring an oncogenic KRas mutation displayed a significantly increased sphere forming efficiency. This effect was blocked by the non-specific beta-blocker propranolol and the selective beta2-blocker ICI 188,551. Stimulation of pancreatic sphere formation from KC mice induced by adrenergic signaling from dorsal root ganglia in vitro was also prevented by selective blockage of the beta2-adrenergic signaling pathway. While surgical or chemical (Botulinum toxin A) denervation of the pancreas appeared not to retard the development precancerous lesions in KC mice, denervation significantly increased the survival when performed in mice after a tumor (3-5mm) was detected by high–resolution ultrasound imaging. In contrast, stress accelerated pancreatic cancer development in KC mice. The effects of stress were prevented by treatment with the selective ADRB2 antagonist ICI 188,551. Conclusions: Taken together, our data suggests that an increased level of stress and an increased level of systemic catecholamines may promote pancreatic carcinogenesis in its early stages. During this phase, patients might benefit from pharmacological inhibition of stress-induced signaling. The progression of pancreatic cancer seems to depend on the local delivery of catecholamines to the microenvironment, and thus patients might also benefit by additional targeting of the ADRB2 signaling pathway. Citation Format: Bernhard W. Renz, Christoph B. Westphalen, Xiaowei Chen, Yoku Hayakawa, Yoshihiro Takemoto, Marina Macchini, Daniel L. Worthley, Samuel Asfaha, Axel Kleespies, Helen Remotti, Kenneth P. Olive, Timothy C. Wang. Adrenergic signaling promotes pancreatic tumor initiation and progression. [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer: Innovations in Research and Treatment; May 18-21, 2014; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2015;75(13 Suppl):Abstract nr B73.