Helicobacter pylori and pancreatic diseases

Novel carbonic anhydrase inhibitors for the treatment of Helicobacter pylori infection

INTRODUCTION

Helicobacter pylori, the causative agent of peptic ulcer, gastritis, and gastric cancer encodes two carbonic anhydrases (CA, EC 4.2.1.1) belonging to the α- and β-class (HpCAα/β), which have been validated as antibacterial drug targets. Acetazolamide and ethoxzolamide were also clinically used for the management of peptic ulcer.

AREAS COVERED

Sulfonamides were the most investigated HpCAα/β compounds, with several low nanomolar inhibitors identified, some of which also crystallized as adducts with HpCAα, allowing for the rationalization of the structure-activity relationship. Few data are available for other classes of inhibitors, such as phenols, sulfamides, sulfamates, dithiocarbamates, arylboronic acids, some of which showed effective in vitro inhibition and for phenols, also inhibition of planktonic growth, biofilm formation, and outer membrane vesicles spawning.

EXPERT OPINION

Several recent drug design studies reported selenazoles incorporating seleno/telluro-ethers attached to benzenesulfonamides, hybrids incorporating the EGFR inhibitor erlotinib and benzenesulfonamides, showing KIs < 100 nM against HpCAα and MICs in the range of 8-16 µg/mL for the most active derivatives. Few drug design studies for non-sulfonamide inhibitors were performed to date, although inhibition of these enzymes may help the fight of multidrug resistance to classical antibiotics which emerged in the last decades also for this bacterium.

The phosphatase DUSP22 inhibits UBR2-mediated K63-ubiquitination and activation of Lck downstream of TCR signalling

DUSP22 is a dual-specificity phosphatase that inhibits T cell activation by inactivating the kinase Lck. Here we show that the E3 ubiquitin ligase UBR2 is a positive upstream regulator of Lck during T-cell activation. DUSP22 dephosphorylates UBR2 at specific Serine residues, leading to ubiquitin-mediated UBR2 degradation. UBR2 is also modified by the SCF E3 ubiquitin ligase complex via Lys48-linked ubiquitination at multiple Lysine residues. Single-cell RNA sequencing analysis and UBR2 loss of function experiments showed that UBR2 is a positive regulator of proinflammatory cytokine expression. Mechanistically, UBR2 induces Lys63-linked ubiquitination of Lck at Lys99 and Lys276 residues, followed by Lck Tyr394 phosphorylation and activation as part of TCR signalling. Inflammatory phenotypes induced by TCR-triggered Lck activation or knocking out DUSP22, are attenuated by genomic deletion of UBR2. UBR2-Lck interaction and Lck Lys63-linked ubiquitination are induced in the peripheral blood T cells of human SLE patients, which demonstrate the relevance of the UBR2-mediated regulation of inflammation to human pathology. In summary, we show here an important regulatory mechanism of T cell activation, which finetunes the balance between T cell response and aggravated inflammation.

Unraveling the intricate relationship: Influence of microbiome on the host immune system in carcinogenesis

BACKGROUND

Cancer is an outcome of various disrupted or dysregulated metabolic processes like apoptosis, growth, and self-cell transformation. Human anatomy harbors trillions of microbes, and these microbes actively influence all kinds of human metabolic activities, including the human immune response. The immune system which inherently acts as a sentinel against microbes, curiously tolerates and even maintains a distinct normal microflora in our body. This emphasizes the evolutionarily significant role of microbiota in shaping our adaptive immune system and even potentiating its function in chronic ailments like cancers. Microbes interact with the host immune cells and play a part in cancer progression or regression by modulating immune cells, producing immunosuppressants, virulence factors, and genotoxins.

RECENT FINDINGS

An expanding plethora of studies suggest and support the evidence of microbiome impacting cancer etiology. Several studies also indicate that the microbiome can supplement various cancer therapies, increasing their efficacy. The present review discusses the relationship between bacterial and viral microbiota with cancer, discussing different carcinogenic mechanisms influenced by prokaryotes with special emphasis on their immunomodulatory axis. It also elucidates the potential of the microbiome in transforming the efficacy of immunotherapeutic treatments.

CONCLUSION

This review offers a thorough overview of the complex interaction between the human immune system and the microbiome and its impact on the development of cancer. The microbiome affects the immune responses as well as progression of tumor transformation, hence microbiome-based therapies can vastly improve the effectiveness of cancer immunotherapies. Individual variations of the microbiome and its dynamic variability in every individual impacts the immune modulation and cancer progression. Therefore, further research is required to understand these underlying processes in detail, so as to design better microbiome-immune system axis in the treatment of cancer.

Helicobacter pylori Seropositivity, ABO Blood Type, and Pancreatic Cancer Risk From 5 Prospective Cohorts

BACKGROUND

Helicobacter pylori infection may be a risk factor for pancreatic cancer, particularly infection by strains without the cytotoxin-associated gene A (CagA) virulence factor. Non-O blood type is a known risk factor for pancreatic cancer, and H. pylori gastric colonization occurs largely from bacterial adhesins binding to blood group antigens on gastric mucosa.

METHODS

We included 485 pancreatic cancer cases and 1,122 matched controls from 5 U.S. prospective cohorts. Prediagnostic plasma samples were assessed for H. pylori and CagA antibody titers. Conditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for pancreatic cancer. ABO blood type was assessed using genetic polymorphisms at the ABO gene locus or self-report.

RESULTS

Compared with H. pylori -seronegative participants, those who were seropositive did not demonstrate an increased risk of pancreatic cancer (OR 0.83, 95% CI 0.65-1.06). This lack of association was similar among CagA-seropositive (OR 0.75, 95% CI 0.53-1.04) and -seronegative (OR 0.89, 95% CI 0.65-1.20) participants. The association was also similar when stratified by time between blood collection and cancer diagnosis ( P -interaction = 0.80). Consistent with previous studies, non-O blood type was associated with increased pancreatic cancer risk, but this increase in risk was similar regardless of H. pylori seropositivity ( P -interaction = 0.51).

DISCUSSION

In this nested case-control study, history of H. pylori infection as determined by H. pylori antibody serology was not associated with pancreatic cancer risk, regardless of CagA virulence factor status. The elevated risk associated with non-O blood type was consistent in those with or without H. pylori seropositivity.

Higher dietary total antioxidant capacity is inversely associated with Helicobacter pylori infection among adults: A case-control study

INTRODUCTION

Antioxidants appear to hinder the actions of Helicobacter pylori (H. pylori). The aim of this research was to evaluate the association between dietary total antioxidant capacity (DTAC) and H. pylori infection.

METHODS

A case-control study was carried out among 200 patients with  H. pylori infection and 402 healthy subjects (18-55 years). Dietary data were collected using a validated 168-item quantitative food frequency questionnaire. DTAC was calculated based on the oxygen radical absorbance capacity of each food (except for coffee) reported by the US Department of Agriculture.

RESULTS

Compared with participants in the lowest tertile of DTAC, those in the highest tertile had a significantly lower odds ratio (OR) in the crude model (OR, 0.29; 95% CI, 0.14-0.61; p for trend = 0.001), model 1 (adjustment for age and sex) (OR, 0.37; 95% CI, 0.24-0.58; p for trend < 0.001), and model 2 (adjustment for model 1 plus body mass index, waist circumference, physical activity, smoking, dietary intake of energy and fat) (OR, 0.20; 95% CI, 0.10-0.40; p for trend ≤ 0.001).

CONCLUSIONS

A high DTAC is associated with a reduced risk of H. pylori infection in adults. Further studies are mandatory to elucidate the mechanisms and a dose-effect relationship.

Connecting the Human Microbiome and Pancreatic Cancer

Pancreatic cancer is a deadly disease that is increasing in incidence throughout the world. There are no clear causal factors associated with the incidence of pancreatic cancer; however, some correlation to smoking, diabetes and alcohol has been described. Recently, a few studies have linked the human microbiome (oral and gastrointestinal tract) to pancreatic cancer development. A perturbed microbiome has been shown to alter normal cells while promoting cancer-related processes such as increased cell signaling, immune system evasion and invasion. In this article, we will review in detail the alterations within the gut and oral microbiome that have been linked to pancreatic cancer and explore the ability of other microbiomes, such as the lung and skin microbiome, to contribute to disease development. Understanding ways to identify a perturbed microbiome can result in advancements in pancreatic cancer research and allow for prevention, earlier detection and alternative treatment strategies for patients.

Bacterial Extracellular Vesicles in Gastrointestinal Tract Cancer: An Unexplored Territory

Bacterial extracellular vesicles are membrane-enclosed, lipid bi-layer nanostructures that carry different classes of biomolecules, such as nucleic acids, lipids, proteins, and diverse types of small molecular metabolites, as their cargo. Almost all of the bacteria in the gut secrete extracellular vesicles to assist them in competition, survival, material exchange, host immune modulation, infection, and invasion. The role of gut microbiota in the development, progression, and pathogenesis of gastrointestinal tract (GIT) cancer has been well documented. However, the possible involvement of bacterial extracellular vesicles (bEVs) in GIT cancer pathophysiology has not been given due attention. Studies have illustrated the ability of bEVs to cross physiological barriers, selectively accumulate near tumor cells, and possibly alter the tumor microenvironment (TME). A systematic search of original published works related to bacterial extracellular vesicles on gastrointestinal cancer was performed for this review. The current systemic review outlines the possible impact of gut microbiota derived bEVs in GIT cancer in light of present-day understanding. The necessity of using advanced sequencing technologies, such as genetic, proteomic, and metabolomic investigation methodologies, to facilitate an understanding of the interrelationship between cancer-associated bacterial vesicles and gastrointestinal cancer is also emphasized. We further discuss the clinical and pharmaceutical potential of bEVs, along with future efforts needed to understand the mechanism of interaction of bEVs in GIT cancer pathogenesis.

Helicobacter pylori infection and other bacteria in pancreatic cancer and autoimmune pancreatitis

Helicobacter pylori (H. pylori) is an infectious agent influencing as much as 50% of the world’s population. It is the causative agent for several diseases, most especially gastric and duodenal peptic ulcer, gastric adenocarcinoma and mucosa-associated lymphoid tissue lymphoma of the stomach. A number of other, extragastric manifestations also are associated with H. pylori infection. These include neurological disorders, such as Alzheimer’s disease, demyelinating multiple sclerosis and Parkinson’s disease. There is also evidence for a relationship between H. pylori infection and such dermatological diseases as psoriasis and rosacea as well as a connection with infection and open-angle glaucoma. Generally little is known about the relationship between H. pylori infection and diseases of the pancreas. Most evidence about H. pylori and its potential role in the development of pancreatic diseases concerns pancreatic adenocarcinoma and autoimmune forms of chronic pancreatitis. There is data (albeit not fully consistent) indicating modestly increased pancreatic cancer risk in H. pylori-positive patients. The pathogenetic mechanism of this increase is not yet fully elucidated, but several theories have been proposed. Reduction of antral D-cells in H. pylori-positive patients causes a suppression of somatostatin secretion that, in turn, stimulates increased secretin secretion. That stimulates pancreatic growth and thus increases the risk of carcinogenesis. Alternatively, H. pylori, as a part of microbiome dysbiosis and the so-called oncobiome, is proven to be associated with pancreatic adenocarcinoma development via the promotion of cellular proliferation. The role of H. pylori in the inflammation characteristic of autoimmune pancreatitis seems to be explained by a mechanism of molecular mimicry among several proteins (mostly enzymes) of H. pylori and pancreatic tissue. Patients with autoimmune pancreatitis often show positivity for antibodies against H. pylori proteins. H. pylori, as a part of microbiome dysbiosis, also is viewed as a potential trigger of autoimmune inflammation of the pancreas. It is precisely these relationships (and associated equivocal conclusions) that constitute a center of attention among pancreatologists, immunologists and pathologists. In order to obtain clear and valid results, more studies on sufficiently large cohorts of patients are needed. The topic is itself sufficiently significant to draw the interest of clinicians and inspire further systematic research. Next-generation sequencing could play an important role in investigating the microbiome as a potential diagnostic and prognostic biomarker for pancreatic cancer.

Clinical Significance of Helicobacter pylori Infection on Psoriasis Severity

The aim of the study was to appraise the link between psoriasis and Helicobacter pylori, investigate the influence of H. pylori treatment on psoriasis severity, determine the cutoff value of haptoglobin as a psoriatic biomarker, and determine the most reliable predictor for psoriasis in patients with H. pylori. This study was carried out on 100 adult Saudi participants from the Security Forces Hospital (Riyadh, Kingdom of Saudi Arabia). All participants were allocated into 5 groups (20/group): controls (G1), psoriatic patients (G2), patients with H. pylori (G3), psoriatic patients with untreated H. pylori (G4), and psoriatic patients with treated H. pylori (G5). The study was approved by the ethics committee of Security Forces Hospital, Riyadh, Saudi Arabia. The psoriasis area and severity index (PASI) score, ¹³C-urea breath test (¹³C-UBT), C-reactive protein (CRP), haptoglobin, platelet P-selectin, cluster of differentiation 4/cluster of differentiation 8 (CD4/CD8) ratio, and lymphocyte percentages were recorded. The haptoglobin level was significantly elevated in psoriatic patients compared with G1. In G5, there was significant attenuation in the PASI score, P-selectin, CRP, CD4/CD8 ratio, and lymphocyte percentage compared with G4. There was a significant positive correlation between psoriasis severity and ¹³C-UBT. In addition, ¹³C-UBT and PASI scores were significantly positively correlated with CRP, platelet P-selectin, and percentage of lymphocytes. H. pylori plays a potential role in psoriasis pathogenesis. H. pylori treatment attenuates psoriasis severity. Haptoglobin could be utilized as a psoriatic biomarker with 1.95 g/L as the cutoff value. The most reliable predictor for psoriasis in infected patients with H. pylori is ¹³C-UBT.

Research Progress of Pancreas-Related Microorganisms and Pancreatic Cancer

Pancreatic cancer is one of the most common digestive system cancers. Early diagnosis is difficult owing to the lack of specific symptoms and reliable biomarkers. The cause of pancreatic cancer remains ambiguous. Smoking, drinking, new-onset diabetes, and chronic pancreatitis have been proven to be associated with the occurrence of pancreatic cancer. In recent years, a large number of studies have clarified that a variety of microorganisms colonized in pancreatic cancer tissues are also closely related to the occurrence and development of pancreatic cancer, and the specific mechanisms include inflammatory induction, immune regulation, metabolism, and microenvironment changes caused by microorganism. The mechanism of action of the pancreatic colonized microbiome in the tumor microenvironment, as well as immunotherapy approaches require further study in order to find more evidence to explain the complex relationship between the pancreatic colonized microbiome and PDAC. Relevant studies targeting the microbiome may provide insight into the mechanisms of PDAC development and progression, improving treatment effectiveness and overall patient prognosis. In this article, we focus on the research relating to the microorganisms colonized in pancreatic cancer tissues, including viruses, bacteria, and fungi. We also highlight the microbial diversity in the occurrence, invasion, metastasis, treatment, and prognosis of pancreatic cancer in order to elucidate its significance in the early diagnosis and new therapeutic treatment of pancreatic cancer, which urgently need to be improved in clinical practice. The elimination or increase in diversity of the pancreatic microbiome is beneficial for prolonging the survival of PDAC patients, improving the response to chemotherapy drugs, and reducing tumor burden. The colonization of microorganisms in the pancreas may become a new hotspot in the diagnosis and treatment of pancreatic cancer.

Association between glycemic index and Helicobacter pylori infection risk among adults: A case-control study

OBJECTIVES

The aim of this case-control study was to investigate the relationships between carbohydrate consumption, glycemic load (GL), glycemic index (GI), and the risk of Helicobacter pylori infection among adults admitted to an Iranian hospital.

METHODS

In this case-control study, we recruited 150 participants with H. pylori infection and 302 healthy participants ages 18 to 55. Dietary GI and GL were assessed using a validated 168-item quantitative food frequency questionnaire. Dietary GL was calculated as a function of GI, carbohydrate content, and the frequency of intake of certain foods.

RESULTS

After adjustment for potential confounders, and comparing the highest tertile with the lowest tertile, a significant direct association was observed between the consumption of carbohydrates (odds ratio [OR] = 2.87; 95% confidence interval [CI], 1.18-6.96; P for trend = 0.017), GI (OR = 3.70; 95% CI, 2.01-6.81; P for trend < 0.001), GL (OR = 3.06; 95% CI, 1.43-6.54; P for trend = 0.001), the consumption of bread and refined-grain products (OR = 4.24; 95% CI, 2.22-8.11; P for trend < 0.001), and the odds of H. pylori infection (OR = 2.22; 95% CI, 1.30-3.79; P for trend = 0.003).

CONCLUSIONS

Our data suggest that a high dietary GL, high GI, and high consumption of dietary carbohydrates significantly elevate the risk of H. pylori infection. Also, the amount of bread and refined-grain products consumed had a significant positive relationship with H. pylori infection.

Review: Extragastric diseases and Helicobacter pylori

The involvement of Helicobacter pylori infection in many extra-gastroduodenal manifestations remains a fascinating field of investigation. However, for several of these supposed associations, the potential pathogenic mechanism remains unclear. The present review highlights the main associations of H pylori with extra-gastroduodenal manifestations reported during the last year. We searched for the most relevant studies on this topic, published between April 2019 and March 2020, identified using the term "Helicobacter" in the MEDLINE/Pubmed database. Consistent data emerged from studies investigating metabolic syndrome and ischaemic cardiovascular diseases. Other reported fields of investigation were hepatology, especially focused on non-alcoholic steatohepatitis, neurology, including Parkinson's disease and Alzheimer's disease, as well as dermatology. Inflammatory bowel disease (IBD), that comprises Crohn's disease and ulcerative colitis, may originate from a dysregulation of the host's immune response to commensal bacteria in individuals with genetic predisposition. The reduction of biodiversity and other specific imbalances in the faecal microbiome composition of IBD patients compared to that of healthy controls support this hypothesis. In this context, an inverse correlation between H pylori infection and IBD prevalence has been confirmed. Similar results were found in patients with kidney diseases and allergic manifestations. There are indications of the possible involvement of H pylori infection in metabolic syndrome and ischaemic cardiovascular diseases. However, due to a series of factors linked to study designs and the multifactorial pathogenesis of some diseases, further studies are needed.

The association of Helicobacter pylori with pancreatic cancer

Background & Aims

Infection with Helicobacter pylori (HP) affects 50% of the world. Previous studies have suggested an association between HP and pancreatic adenocarcinoma (PC). These association studies have been limited in their ability to identify the incidence and risk factors of PC among HP infected individuals and the impact of HP eradication on PC.

Methods

Retrospective cohort study within the Veterans Administration of 103,595 patients (median age 62.3; 92.0% male) with HP diagnosis based on pathology, stool antigen, urea breath test, or serum antibody between 1/1/1994-12/31/2018. Primary outcome was future PC diagnosis. A time to event with competing risk analysis was performed, evaluating patient demographics and history, method of HP diagnosis, and whether the patient received HP treatment. Secondary analysis of those treated evaluated whether confirmed eradication was associated with PC.

Results

The cumulative incidence of PC at 5 and 10 years was 0.37% and 0.54%, respectively. Patients who developed PC were older, male, reside in areas with higher poverty. Preceding diabetes and chronic pancreatitis were strongly associated with PC. Factors not associated with PC included receiving an eradication regimen, diagnosis of an active infection (versus prior exposure alone), and eradication of HP.

Conclusions

PC after HP is rare. Chronic pancreatitis is the main risk factor for PC. Active HP infection, treatment of HP infection, or eradication of HP are not associated with future PC. This study calls into question the association between PC and HP.

Body site-dependent variations of microbiota in pancreatic cancer pathophysiology

Lack of specific symptoms and reliable biomarkers, along with aggressive nature and resistance to therapies makes pancreatic cancer (PC) one of the leading causes of death from cancer worldwide. The search for new diagnostic, prognostic, predictive, and therapeutic tools that could improve clinical outcomes of patients has led, in recent years, to the investigation of potential roles for the microbiota in the pathogenesis of this disease. The human microbiota encompasses trillions of microorganisms residing within several body tissues and organs, where they provide beneficial functions for host homeostasis and health. Derangements of the microbial ecology in different anatomic districts have been described in PC, as in many other diseases, both in patients and in animal models. In detail, infection from the gastric pathogen Helicobacter pylori and changes in composition and diversity of oral, intestinal, and pancreatic microbiota have been found to associate with PC. Future research should assess how to potentially exploit such differences in microbiota composition as diagnostic, prognostic, or predictive biomarkers, and as targets for therapeutic interventions, in the hope of improving the dismal prognosis of this insidious cancer.

Exploring the microbiota to better understand gastrointestinal cancers physiology

Gastrointestinal cancers account for around 40% of cancer-related deaths worldwide, representing a global health burden. There is a growing body of evidence highlighting the link between microbiota and gastrointestinal tumorigenesis and/or resistance to therapy. In the present manuscript, we reviewed the published studies on the relationship between the microbiota and the different gastrointestinal tumors, namely, gastric, colorectal and esophageal, including also the cancer of accessory organs such as liver and pancreas. There is an emergent interest in the manipulation of gastrointestinal microflora in order to understand the gastrointestinal tumorigenesis' processes and the establishment of chemoresistance mechanisms.

Human Gut Microbiota and Gastrointestinal Cancer

Human gut microbiota play an essential role in both healthy and diseased states of humans. In the past decade, the interactions between microorganisms and tumors have attracted much attention in the efforts to understand various features of the complex microbial communities, as well as the possible mechanisms through which the microbiota are involved in cancer prevention, carcinogenesis, and anti-cancer therapy. A large number of studies have indicated that microbial dysbiosis contributes to cancer susceptibility via multiple pathways. Further studies have suggested that the microbiota and their associated metabolites are not only closely related to carcinogenesis by inducing inflammation and immune dysregulation, which lead to genetic instability, but also interfere with the pharmacodynamics of anticancer agents. In this article, we mainly reviewed the influence of gut microbiota on cancers in the gastrointestinal (GI) tract (including esophageal, gastric, colorectal, liver, and pancreatic cancers) and the regulation of microbiota by diet, prebiotics, probiotics, synbiotics, antibiotics, or the Traditional Chinese Medicine. We also proposed some new strategies in the prevention and treatment of GI cancers that could be explored in the future. We hope that this review could provide a comprehensive overview of the studies on the interactions between the gut microbiota and GI cancers, which are likely to yield translational opportunities to reduce cancer morbidity and mortality by improving prevention, diagnosis, and treatment.

Human Gut Microbiota and Gastrointestinal Cancer

Human gut microbiota play an essential role in both healthy and diseased states of humans. In the past decade, the interactions between microorganisms and tumors have attracted much attention in the efforts to understand various features of the complex microbial communities, as well as the possible mechanisms through which the microbiota are involved in cancer prevention, carcinogenesis, and anti-cancer therapy. A large number of studies have indicated that microbial dysbiosis contributes to cancer susceptibility via multiple pathways. Further studies have suggested that the microbiota and their associated metabolites are not only closely related to carcinogenesis by inducing inflammation and immune dysregulation, which lead to genetic instability, but also interfere with the pharmacodynamics of anticancer agents. In this article, we mainly reviewed the influence of gut microbiota on cancers in the gastrointestinal (GI) tract (including esophageal, gastric, colorectal, liver, and pancreatic cancers) and the regulation of microbiota by diet, prebiotics, probiotics, synbiotics, antibiotics, or the Traditional Chinese Medicine. We also proposed some new strategies in the prevention and treatment of GI cancers that could be explored in the future. We hope that this review could provide a comprehensive overview of the studies on the interactions between the gut microbiota and GI cancers, which are likely to yield translational opportunities to reduce cancer morbidity and mortality by improving prevention, diagnosis, and treatment.

Dietary Patterns are Associated with Helicobacter Pylori Infection in Chinese Adults: A Cross-Sectional Study

Previous studies indicated that food consumption was associated with Helicobacter pylori infection, but no study has yet investigated the association between Helicobacter pylori infection and dietary patterns. The aim of this study was to evaluate the associations between Helicobacter pylori infection and dietary patterns in Tianjin, China. The final cross-sectional study population comprised 10407 participants. Dietary consumption of participants was assessed via food frequency questionnaire. Factor analysis was used to identify dietary patterns, and Helicobacter pylori infection status was diagnosis by H. pylori urease Immunogold Testing kit. Participants in the highest quartile of the high-carbohydrate/sweet pattern showed a multivariable-adjusted OR (95% CI) of 1.65 (1.27–2.17) for the prevalence of H. pylori infection compared with those in the lowest quartile. The multiple adjusted OR for scores of the extreme quartile of high-protein/cholesterol pattern was 0.75 (95% CI, 0.57–0.98). This study demonstrated that a diet rich in carbohydrates and sweets was positively associated with the prevalence of H. pylori infection; interestingly, a diet characterized by high intake of animal offal, animal blood, fish, seafood, and poultry was associated with a reduction of prevalence of H. pylori infection.

Environmental risk factors for pancreatic cancer: an update

Pancreatic cancer (PC) is one of the most aggressive diseases. Only 10 % of all PC cases are thought to be due to genetic factors. Here, we analyzed the most recently published case-control association studies, meta-analyses, and cohort studies with the aim to summarize the main environmental factors that could have a role in PC. Among the most dangerous agents involved in the initiation phase, there are the inhalation of cigarette smoke, and the exposure to mutagenic nitrosamines, organ-chlorinated compounds, heavy metals, and ionizing radiations. Moreover, pancreatitis, high doses of alcohol drinking, the body microbial infections, obesity, diabetes, gallstones and/or cholecystectomy, and the accumulation of asbestos fibers seem to play a crucial role in the progression of the disease. However, some of these agents act both as initiators and promoters in pancreatic acinar cells. Protective agents include dietary flavonoids, marine omega-3, vitamin D, fruit, vegetables, and the habit of regular physical activity. The identification of the factors involved in PC initiation and progression could be of help in establishing novel therapeutic approaches by targeting the molecular signaling pathways responsive to these stimuli. Moreover, the identification of these factors could facilitate the development of strategies for an early diagnosis or measures of risk reduction for high-risk people.

Meta-analysis of association between Helicobacter pylori infection and multiple sclerosis

Despite recent research focus on the association between Helicobacter pylori (H. pylori) infection and multiple sclerosis (MS) there is no consensus about the findings. To obtain a more comprehensive estimate of the association we conducted a meta-analysis to determine the prevalence of H. pylori infection in MS patients and healthy controls. Pubmed and EMBASE were searched to identify eligible studies. Nine studies were selected for inclusion, involving 2806 cases (1553 patients with MS and 1253 controls). Overall, the prevalence of H. pylori infection in MS patients was lower than that in control groups (24.66% vs. 31.84%, OR=0.69, 95% CI: 0.57-0.83, P<0.0001). Subgroup analysis revealed that the levels of H.pylori infection among MS patients were lower than for control subjects in Western countries (11.90% vs. 16.08%, OR=0.63, 95% CI: 0.43-0.91, P=0.01), but were not statistically significant in Eastern countries (39.39% vs. 43.82%, OR=0.79, 95% CI: 0.55-1.14, P=0.20). Our data show that H. pylori infection and MS is negatively correlated, especially in Western countries. Whether H. pylori infection is a protective factor against MS risk should thus be addressed in large-scale and prospective studies.

Current therapeutic strategies for advanced pancreatic cancer: A review for clinicians

Pancreatic cancer (PC) would become the second leading cause of cancer death in the near future, despite representing only 3% of new cancer diagnosis. Survival improvement will come from a better knowledge of risk factors, earlier diagnosis, better integration of locoregional and systemic therapies, as well as the development of more efficacious drugs rising from a deeper understanding of disease biology. For patients with unresectable, non-metastatic disease, combined strategies encompassing primary chemotherapy and radiation seems to be promising. In fit patients, new polychemotherapy regimens can lead to better outcomes in terms of slight but significant survival improvement associated with a positive impact on quality of life. The upfront use of these regimes can also increase the rate of radical resections in borderline resectable and locally advanced PC. Second line treatments showed to positively affect both overall survival and quality of life in fit patients affected by metastatic disease. At present, oxaliplatin-based regimens are the most extensively studied. Nonetheless, other promising drugs are currently under evaluation. Presently, in addition to surgery and conventional radiation therapy, new locoregional treatment techniques are emerging as alternative options in the multimodal approach to patients or diseases not suitable for radical surgery. As of today, in contrast with other types of cancer, targeted therapies failed to show relevant activity either alone or in combination with chemotherapy and, thus, current clinical practice does not include them. Up to now, despite the fact of extremely promising results in different tumors, also immunotherapy is not in the actual therapeutic armamentarium for PC. In the present paper, we provide a comprehensive review of the current state of the art of clinical practice and research in PC aiming to offer a guide for clinicians on the most relevant topics in the management of this disease.

Overlap of IgG4-related Disease and Primary Biliary Cirrhosis Complicated with Autoimmune Thrombocytopenia

A 63-year-old woman was referred to Fukushima Red Cross Hospital with an enlargement of the left submandibular gland and subcutaneous bleeding in the chest and legs. A diffuse enlargement of the pancreas was also detected by abdominal computed tomography, and laboratory data showed severe thrombocytopenia. She was diagnosed with IgG4-related disease (IgG4-RD) complicated with autoimmune thrombocytopenia and was treated with methylprednisolone, after which the number of platelets favorably increased. Further investigation for liver dysfunction revealed underlying primary biliary cirrhosis (PBC). We herein report a rare case of IgG4-RD overlapping PBC complicated with autoimmune thrombocytopenia.

Pathogenic Microorganisms and Pancreatic Cancer

BACKGROUND

Pancreatic cancer is one of the most lethal cancers worldwide. No effective screening methods exist, and available treatment modalities do not effectively treat the disease. Established risk factors for pancreatic cancer, including smoking, chronic pancreatitis, obesity and type 2 diabetes mellitus, collectively account for less than half of all pancreatic cancer cases. Accumulating reports have demonstrated that there is an association between pathogenic microorganisms and pancreatic cancer.

SUMMARY

A substantial amount of preclinical and clinical evidence suggests that microbiota are likely to influence pancreatic carcinogenesis. This review summarizes the literature on studies examining infections that have been linked to pancreatic cancer.

KEY MESSAGE

Helicobacter pylori infection may be a risk factor for pancreatic cancer; chronic hepatitis virus and oral microbiota may also play a role in pancreatic carcinogenesis.

PRACTICAL IMPLICATIONS

Considering the worldwide burden of the disease, the association between microbiota and pancreatic cancer in this review may provide new ideas to prevent and treat pancreatic cancer more efficiently. Further studies in this direction are urgently needed.

[Helicobacter pylori infection and extragastroduodenal diseases]

At present, the clinical significance of Helicobacter pylori infection has been validly determined within the development of a diversity of gastroduodenal diseases, including chronic gastritis, gastroduodenal ulcer, MALT lymphoma, and gastric adenocarcinoma. The Expert Council's Maastricht IV consensus (2010) determining international standards for the diagnosis and treatment of H. pylori infection is that there is evidence that the latter may be associated with the development of a number of extragastroduodenal diseases (EGDDs) presented by iron-deficiency anemia of unspecified etiology, idiopathic thrombocytopenic purpura, and vitamin B12 deficiency. In these diseases, it is recommended that infection with H. pylori be diagnosed and, if the test is positive, this microorganism be eradicated. A large number of investigations have been recently conducted to examine the association of H. pylori infection with other EGDDs. This paper reviews theoretical and epidemiological data on the association of H. pylori with diseases of the cardiovascular (atherosclerosis, myocardial infarction) and central nervous (Alzheimer's disease, Parkinson's disease) systems, pancreas (autoimmune pancreatitis, pancreatic cancer), oncological (colonic adenomas, colorectal cancer, hepatocellular carcinoma), dermatological (chronic spontaneous urticaria), and other EGDDs. The review highlights the potential protective role of H. pylori in diseases with the atopic element of genesis and a complicated course of gastroesophageal reflux disease (Barrett's esophagus, esophageal adenocarcinoma).