Effect of Helicobacter pylori infection on IL-8, IL-1beta and COX-2 expression in patients with chronic gastritis and gastric cancer

Infiltration to infection: key virulence players of Helicobacter pylori pathogenicity

PURPOSE

This study aims to comprehensively review the multifaceted factors underlying the successful colonization and infection process of Helicobacter pylori (H. pylori), a prominent Gram-negative pathogen in humans. The focus is on elucidating the functions, mechanisms, genetic regulation, and potential cross-interactions of these elements.

METHODS

Employing a literature review approach, this study examines the intricate interactions between H. pylori and its host. It delves into virulence factors like VacA, CagA, DupA, Urease, along with phase variable genes, such as babA, babC, hopZ, etc., giving insights about the bacterial perspective of the infection The association of these factors with the infection has also been added in the form of statistical data via Funnel and Forest plots, citing the potential of the virulence and also adding an aspect of geographical biasness to the virulence factors. The biochemical characteristics and clinical relevance of these factors and their effects on host cells are individually examined, both comprehensively and statistically.

RESULTS

H. pylori is a Gram-negative, spiral bacterium that successfully colonises the stomach of more than half of the world's population, causing peptic ulcers, gastric cancer, MALT lymphoma, and other gastro-duodenal disorders. The clinical outcomes of H. pylori infection are influenced by a complex interplay between virulence factors and phase variable genes produced by the infecting strain and the host genetic background. A meta-analysis of the prevalence of all the major virulence factors has also been appended.

CONCLUSION

This study illuminates the diverse elements contributing to H. pylori's colonization and infection. The interplay between virulence factors, phase variable genes, and host genetics determines the outcome of the infection. Despite biochemical insights into many factors, their comprehensive regulation remains an understudied area. By offering a panoramic view of these factors and their functions, this study enhances understanding of the bacterium's perspective, i.e. H. pylori's journey from infiltration to successful establishment within the host's stomach.

Inflammatory microenvironment in gastric premalignant lesions: implication and application

Gastric precancerous lesions (GPL) are a major health concern worldwide due to their potential to progress to gastric cancer (GC). Understanding the mechanism underlying the transformation from GPL to GC can provide a fresh insight for the early detection of GC. Although chronic inflammation is prevalent in the GPL, how the inflammatory microenvironment monitored the progression of GPL-to-GC are still elusive. Inflammation has been recognized as a key player in the progression of GPL. This review aims to provide an overview of the inflammatory microenvironment in GPL and its implications for disease progression and potential therapeutic applications. We discuss the involvement of inflammation in the progression of GPL, highlighting Helicobacter pylori (H. pylori) as a mediator for inflammatory microenvironment and a key driver to GC progression. We explore the role of immune cells in mediating the progression of GPL, and focus on the regulation of inflammatory molecules in this disease. Furthermore, we discuss the potential of targeting inflammatory pathways for GPL. There are currently no specific drugs for GPL treatment, but traditional Chinese Medicine (TCM) and natural antioxidants, known as antioxidant and anti-inflammatory properties, exhibit promising effects in suppressing or reversing the progression of GPL. Finally, the challenges and future perspectives in the field are proposed. Overall, this review highlights the central role of the inflammatory microenvironment in the progression of GPL, paving the way for innovative therapeutic approaches in the future.

Outer Membrane Vesicles (OMVs) as Biomedical Tools and Their Relevance as Immune-Modulating Agents against H. pylori Infections: Current Status and Future Prospects

Outer membrane vesicles (OMVs) are lipid-membrane-bounded nanoparticles that are released from Gram-negative bacteria via vesiculation of the outer membrane. They have vital roles in different biological processes and recently, they have received increasing attention as possible candidates for a broad variety of biomedical applications. In particular, OMVs have several characteristics that enable them to be promising candidates for immune modulation against pathogens, such as their ability to induce the host immune responses given their resemblance to the parental bacterial cell. Helicobacter pylori (H. pylori) is a common Gram-negative bacterium that infects half of the world's population and causes several gastrointestinal diseases such as peptic ulcer, gastritis, gastric lymphoma, and gastric carcinoma. The current H. pylori treatment/prevention regimens are poorly effective and have limited success. This review explores the current status and future prospects of OMVs in biomedicine with a special focus on their use as a potential candidate in immune modulation against H. pylori and its associated diseases. The emerging strategies that can be used to design OMVs as viable immunogenic candidates are discussed.

Protective effect of valerian extract capsule (VEC) on ethanol- and indomethacin-induced gastric mucosa injury and ameliorative effect of VEC on gastrointestinal motility disorder

CONTEXT

Valerian extract capsule (VEC) is an effective Chinese patent medicine used for gastrointestinal (GI) diseases.

OBJECTIVE

To investigate the detailed pharmacological activity for VEC clinical effects in GI diseases.

MATERIALS AND METHODS

Sprague-Dawley rats were divided into six groups: control, model, and drug-treated (VEC-L, VEC-M, VEC-H, and teprenone). Rats were orally administered VEC (124, 248, 496 mg/kg) and teprenone (21.43 mg/kg) for 3 consecutive days. After 1 h, the five groups (except the control group) were orally given ethanol (10 mL/kg) for 1 h or indomethacin (80 mg/kg) for 7 h. The spasmolytic activity of VEC (0.01-1 mg/mL) on ACh/BaCl₂-induced New Zealand rabbit smooth muscle contraction was performed. The C57BL/6 mice carbon propelling test evaluated the effects of VEC (248-992 mg/kg) on intestinal motility in normal and neostigmine/adrenaline-induced mice.

RESULTS

Compared with the model group, VEC treatment reduced the gastric lesion index and mucosal damage. Further experiments showed that the pathological ameliorative effect of VEC was accompanied by augmentation of the enzymatic antioxidant system and cytoprotective marker (COX-1, p < 0.01; PGI2 p < 0.05;), along with the alleviation of the levels of MPO (ethanol: 15.56 ± 0.82 vs. 12.15 ± 2.60, p < 0.01; indomethacin: 9.65 ± 3.06 vs. 6.36 ± 2.43, p < 0.05), MDA (ethanol: 1.66 ± 0.44 vs. 0.81 ± 0.58, p < 0.01; indomethacin: 1.71 ± 0.87 vs. 1.09 ± 0.43, p < 0.05), and inflammatory mediators. VEC decreased the high tone induced by ACh/BaCl₂ and promoted intestinal transit in normal and neostigmine/adrenaline-induced mice.

DISCUSSION AND CONCLUSIONS

VEC showed a potential gastroprotective effect, suggesting that VEC is a promising phytomedicine for the treatment of GI diseases.

Probiotic Supplements: Their Strategies in the Therapeutic and Prophylactic of Human Life-Threatening Diseases

Chronic diseases and viral infections have threatened human life over the ages and constitute the main reason for increasing death globally. The rising burden of these diseases extends to negatively affecting the economy and trading globally, as well as daily life, which requires inexpensive, novel, and safe therapeutics. Therefore, scientists have paid close attention to probiotics as safe remedies to combat these morbidities owing to their health benefits and biotherapeutic effects. Probiotics have been broadly adopted as functional foods, nutraceuticals, and food supplements to improve human health and prevent some morbidity. Intriguingly, recent research indicates that probiotics are a promising solution for treating and prophylactic against certain dangerous diseases. Probiotics could also be associated with their essential role in animating the immune system to fight COVID-19 infection. This comprehensive review concentrates on the newest literature on probiotics and their metabolism in treating life-threatening diseases, including immune disorders, pathogens, inflammatory and allergic diseases, cancer, cardiovascular disease, gastrointestinal dysfunctions, and COVID-19 infection. The recent information in this report will particularly furnish a platform for emerging novel probiotics-based therapeutics as cheap and safe, encouraging researchers and stakeholders to develop innovative treatments based on probiotics to prevent and treat chronic and viral diseases.

Transcriptional alteration of genes linked to gastritis concerning Helicobacter pylori infection status and its virulence factors

BACKGROUND

Helicobacter pylori infection and heterogeneity in its pathogenesis could describe diversity in the expression of inflammatory genes in the gastric tissue. We aimed to investigate transcriptional alteration of genes linked to gastritis concerning the H. pylori infection status and its virulence factors.

METHODS AND RESULTS

Biopsy samples of 12 infected and 12 non-infected patients with H. pylori that showed moderate chronic gastritis were selected for transcriptional analysis. Genotyping of H. pylori strains was done using PCR and relative expression of inflammatory genes was compared between the infected and non-infected patients using relative quantitative real-time PCR. Positive correlations between transcriptional changes of IL8 with TNF-α and Noxo1 in the infected and TNF-α with Noxo1, MMP7, and Atp4A in the non-infected patients were detected. Six distinct genotypes of H. pylori were detected that showed no correlation with gender, ethnicity, age, endoscopic findings, and transcriptional levels of host genes. Irrespective of the characterized genotypes, our results showed overexpression of TNF-α, MMP7, Noxo1, and ATP4A in the infected and IL-8, Noxo1, and ATP4A in the non-infected patients.

CONCLUSIONS

A complexity in transcription of genes respective to the characterized H. pylori genotypes in the infected patients was detected in our study. The observed difference in co-regulation of genes linked to gastritis in the infected and non-infected patients proposed involvement of different regulatory pathways in the inflammation of the gastric tissue in the studied groups.

The role of the bacterial microbiome in the treatment of cancer

The human microbiome is defined as the microorganisms that reside in or on the human body, such as bacteria, viruses, fungi, and protozoa, and their genomes. The human microbiome participates in the modulation of human metabolism by influencing several intricate pathways. The association between specific bacteria or viruses and the efficacy of cancer treatments and the occurrence of treatment-related toxicity in cancer patients has been reported. However, the understanding of the interaction between the host microbiome and the cancer treatment response is limited, and the microbiome potentially plays a greater role in the treatment of cancer than reported to date. Here, we provide a thorough review of the potential role of the gut and locally resident bacterial microbiota in modulating responses to different cancer therapeutics to demonstrate the association between the gut or locally resident bacterial microbiota and cancer therapy. Probable mechanisms, such as metabolism, the immune response and the translocation of microbiome constituents, are discussed to promote future research into the association between the microbiome and other types of cancer. We conclude that the interaction between the host immune system and the microbiome may be the basis of the role of the microbiome in cancer therapies. Future research on the association between host immunity and the microbiome may improve the efficacy of several cancer treatments and provide insights into the cause of treatment-related side effects.

Multidimensional role of bacteria in cancer: Mechanisms insight, diagnostic, preventive and therapeutic potential

The active role of bacteria in oncogenesis has long been a topic of debate. Although, it was speculated to be a transmissible cause of cancer as early as the 16th-century, yet the idea about the direct involvement of bacteria in cancer development has only been explored in recent decades. More recently, several studies have uncovered the mechanisms behind the carcinogenic potential of bacteria which are inflammation, immune evasion, pro-carcinogenic metabolite production, DNA damage and genomic instability. On the other side, the recent development on the understanding of tumor microenvironment and technological advancements has turned this enemy into an ally. Studies using bacteria for cancer treatment and detection have shown noticeable effects. Therapeutic abilities of bioengineered live bacteria such as high specificity, selective cytotoxicity to cancer cells, responsiveness to external signals and control after ingestion have helped to overcome the challenges faced by conventional cancer therapies and highlighted the bacterial based therapy as an ideal approach for cancer treatment. In this review, we have made an effort to compile substantial evidence to support the multidimensional role of bacteria in cancer. We have discussed the multifaceted role of bacteria in cancer by highlighting the wide impact of bacteria on different cancer types, their mechanisms of actions in inducing carcinogenicity, followed by the diagnostic and therapeutic potential of bacteria in cancers. Moreover, we have also highlighted the existing gaps in the knowledge of the association between bacteria and cancer as well as the limitation and advantage of bacteria-based therapies in cancer. A better understanding of these multidimensional roles of bacteria in cancer can open up the new doorways to develop early detection strategies, prevent cancer, and develop therapeutic tactics to cure this devastating disease.

Effects of natural capsicum extract on growth performance, nutrient utilization, antioxidant status, immune function, and meat quality in broilers

This research was conducted to determine the effects of natural capsaicin extract (NCE) as an alternative to the antibiotic (chlortetracycline, CTC) on growth performance, antioxidant capacity, immune function, and meat quality of broiler chickens. A total of 168 one-day-old Arbor Acre male broiler chickens with an average weight of 46.4 ± 0.6 g were randomly allotted to 3 dietary treatments, with 7 replicates per treatment and 8 broilers per pen. These 3 dietary treatments included a corn-soybean meal basal diet (CON), a basal diet + 75 mg/kg CTC (CTC), and a basal diet + 80 mg/kg NCE (NCE). Broilers from the NCE group showed higher average daily gain compared to broilers from the CON group at all stages (P < 0.05). On d 42, NCE supplementation improved dietary nitrogen-corrected apparent metabolizable energy compared to nonsupplemented or CTC-supplemented diets (P < 0.05). The digestibility of organic matter and crude protein were higher in the NCE diet than in the CON or CTC diets (P < 0.05). Higher relative weight of bursa of Fabricius was observed in broilers fed NCE diets compared with CON (P < 0.05). Pancreatic trypsin and lipase activities were significantly increased in the NCE group compared with those in the CON group (P < 0.05). The value of lightness (L*) of breast muscles from broilers fed NCE diets was significantly lower compared to those fed CON diets (P < 0.05). Broilers fed NCE diets also had higher levels of serum total antioxidant capacity, glutathione peroxidase, superoxide dismutase, and lower levels of interleukin-1β, and tumor necrosis factor-α compared with broilers fed CON diets (P < 0.05). The liver catalase activity of broilers was also significantly increased in the NCE group than the CON group (P < 0.05). In addition, broilers from NCE group had lower concentrations of serum urea-N, low-density lipoprotein cholesterol, and total cholesterol, and higher concentration of growth hormone compared with those from the CON group (P < 0.05). Therefore, we concluded that supplementation of 80 mg/kg of NCE in diets could improve growth performance, nutrient digestibility, antioxidant status, immune function, and meat quality in broilers.

Astaxanthin Inhibits Helicobacter pylori-induced Inflammatory and Oncogenic Responses in Gastric Mucosal Tissues of Mice

Helicobacter pylori is recognized as a risk factor for gastric carcinogenesis. The chronic exposure of gastric epithelium to H. pylori induces a prolonged inflammatory state that may progress to gastric cancer. Astaxanthin, a pinkish antioxidant carotenoid, abundant in marine organisms, is known for its protective effect against inflammation and multiple types of cancer. The purpose of this study was to examine the effect of astaxanthin on H. pylori-induced oxidative injury, inflammation, and oncogene expression in gastric mucosal tissues of the infected mice. Mice were inoculated using oral gavage with H. pylori suspension (10⁸ colony forming unit of H. pylori/0.1 mL) for three days, after which they were fed astaxanthin-supplemented diet (5 mg/kg body weight/day for seven weeks). The effects of astaxanthin on H. pylori-induced increase in lipid peroxide (LPO) production, myeloperoxidase (MPO) activity, expression of the inflammatory cytokine IFN-_γ and oncogenes (c-myc and cyclin D1), and the accompanying histologic changes in gastric mucosal tissues were evaluated. H. pylori infection increased the level of LPO, MPO activity, and the expression of IFN-_γ, c-myc, and cyclin D1 in gastric mucosal tissues of mice. H. pylori infection induced neutrophil infiltration and hyperplasia of gastric mucosa. Astaxanthin supplementation attenuated these effects. In conclusion, consumption of astaxanthin-rich foods may prevent H. pylori-associated oxidative damage and inflammatory and oncogenic responses in gastric mucosal tissues.

Seropositivity for pathogens associated with chronic infections is a risk factor for all-cause mortality in the elderly: findings from the Memory and Morbidity in Augsburg Elderly (MEMO) Study

Immunostimulation by chronic infection has been linked to an increased risk for different non-communicable diseases, which in turn are leading causes of death in high- and middle-income countries. Thus, we investigated if a positive serostatus for pathogens responsible for common chronic infections is individually or synergistically related to reduced overall survival in community dwelling elderly. We used data of 365 individuals from the German MEMO (Memory and Morbidity in Augsburg Elderly) cohort study with a median age of 73 years at baseline and a median follow-up of 14 years. We examined the effect of a positive serostatus at baseline for selected pathogens associated with chronic infections (Helicobacter pylori, Borrelia burgdorferi sensu lato, Toxoplasma gondii, cytomegalovirus, Epstein-Barr virus, herpes simplex virus 1/2, and human herpesvirus 6) on all-cause mortality with multivariable parametric survival models. We found a reduced survival time in individuals with a positive serostatus for Helicobacter pylori (accelerated failure time (AFT) - 15.92, 95% CI - 29.96; - 1.88), cytomegalovirus (AFT - 22.81, 95% CI - 36.41; - 9.22) and Borrelia burgdorferi sensu lato (AFT - 25.25, 95% CI - 43.40; - 7.10), after adjusting for potential confounders. The number of infectious agents an individual was seropositive for had a linear effect on all-cause mortality (AFT per additional infection - 12.42 95% CI - 18.55; - 6.30). Our results suggest an effect of seropositivity for Helicobacter pylori, cytomegalovirus, and Borrelia burgdorferi sensu lato on all-cause mortality in older community dwelling individuals. Further research with larger cohorts and additional biomarkers is required, to assess mediators and molecular pathways of this effect.

Unveiling the Crucial Role of Type IV Secretion System and Motility of Helicobacter pylori in IL-1β Production via NLRP3 Inflammasome Activation in Neutrophils

Helicobacter pylori is a gram-negative, microaerophilic, and spiral-shaped bacterium and causes gastrointestinal diseases in human. IL-1β is a representative cytokine produced in innate immune cells and is considered to be a key factor in the development of gastrointestinal malignancies. However, the mechanism of IL-1β production by neutrophils during H. pylori infection is still unknown. We designed this study to identify host and bacterial factors involved in regulation of H. pylori-induced IL-1β production in neutrophils. We found that H. pylori-induced IL-1β production is abolished in NLRP3-, ASC-, and caspase-1/11-deficient neutrophils, suggesting essential role for NLRP3 inflammasome in IL-1β response against H. pylori. Host TLR2, but not TLR4 and Nod2, was also required for transcription of NLRP3 and IL-1β as well as secretion of IL-1β. H. pylori lacking cagL, a key component of the type IV secretion system (T4SS), induced less IL-1β production in neutrophils than did its isogenic WT strain, whereas vacA and ureA were dispensable. Moreover, T4SS was involved in caspase-1 activation and IL-1β maturation in H. pylori-infected neutrophils. We also found that FlaA is essential for H. pylori-mediated IL-1β production in neutrophils, but not dendritic cells. TLR5 and NLRC4 were not required for H. pylori-induced IL-1β production in neutrophils. Instead, bacterial motility is essential for the production of IL-1β in response to H. pylori. In conclusion, our study shows that host TLR2 and NLRP3 inflammasome and bacterial T4SS and motility are essential factors for IL-1β production by neutrophils in response to H. pylori.

Association of Helicobacter pylori babA2 gene and gastric cancer risk: a meta-analysis

Background

The association of Helicobacter pylori (H. pylori) babA2 gene with gastric cancer (GC) was reported by several studies, but results were inconsistent. This meta-analysis was performed to investigate the relationship between H. pylori babA2 gene and GC risk.

Methods

Case-control studies involving the association between H. pylori babA2 gene and GC risk were systematically identified from PubMed databases. A meta-analysis was used to pool studies and to estimate odds ratios (ORs) with 95% confidence intervals (CIs) of H. pylori babA2 gene associated with GC risk.

Results

Twenty studies were identified with a total of 1289 GC cases and 1081 controls. H. pylori babA2 gene was associated with an increased risk of GC by 2.05 fold (95% CI, 1.30–3.24, P = 0.002). In subgroup analysis, we found that H. pylori babA2 gene was significantly associated with GC risk in Asian population (OR = 2.63, 95% CI: 1.36–5.09 P = 0.004) but not in South American population (OR = 1.35, 95% CI: 0.69–2.64, P = 0.379).

Conclusions

This meta-analysis indicates that H. pylori babA2 gene may be associated with increased risk of GC, especially in Asian population.

The Bacterial Microbiota of Gastrointestinal Cancers: Role in Cancer Pathogenesis and Therapeutic Perspectives

The microbiota has an essential role in the pathogenesis of many gastrointestinal diseases including cancer. This effect is mediated through different mechanisms such as damaging DNA, activation of oncogenic pathways, production of carcinogenic metabolites, stimulation of chronic inflammation, and inhibition of antitumor immunity. Recently, the concept of "pharmacomicrobiomics" has emerged as a new field concerned with exploring the interplay between drugs and microbes. Mounting evidence indicates that the microbiota and their metabolites have a major impact on the pharmacodynamics and therapeutic responses toward anticancer drugs including conventional chemotherapy and molecular-targeted therapeutics. In addition, microbiota appears as an attractive target for cancer prevention and treatment. In this review, we discuss the role of bacterial microbiota in the pathogenesis of different cancer types affecting the gastrointestinal tract system. We also scrutinize the evidence regarding the role of microbiota in anticancer drug responses. Further, we discuss the use of probiotics, fecal microbiota transplantation, and antibiotics, either alone or in combination with anticancer drugs for prevention and treatment of gastrointestinal tract cancers.

N-terminal region of Helicobacter pylori CagA induces IL-8 production in gastric epithelial cells via the β1 integrin receptor

Introduction. Helicobacter pylori is associated with gastrointestinal disease, most notably gastric cancer. Cytotoxin-associated antigen A (CagA), an important virulence factor for H. pylori pathogenicity, induces host cells to release inflammatory factors, especially interleukin-8 (IL-8). The mechanism by which C-terminal CagA induces IL-8 production has been studied extensively, but little is known about the role of the N-terminus.

Aim. To investigate the effect of CagA303–456aa (a peptide in the N-terminal CagA) on IL-8 production by gastric epithelial cells.

Methodology. CagA303-456aa was produced by a prokaryotic expression system and purified by Strep-tag affinity chromatography. An integrin β1 (ITGB1)-deficient AGS cell line was constructed using the CRISPR/Cas9 technique, and NCTC 11637 cagA and/or cagL knockout mutants were constructed via homologous recombination. The levels of IL-8 production were determined by enzyme-linked immunosorbent assay (ELISA), and p38 and ERK1/2 phosphorylation were examined by Western blot.

Results. CagA303-456aa induced IL-8 expression by AGS cells. IL-8 induction by CagA303-456aawas specifically inhibited by ITGB1 deficiency. Notably, CagA303-456aa activated the phosphorylation of both p38 and ERK1/2, and blocking p38 and ERK1/2 activity significantly reduced IL-8 induction by CagA303-456aa. ITGB1 deficiency also inhibited the activation of p38 phosphorylation by CagA303-456aa. Finally, experiments in CagA and/or CagL knockout bacterial lines demonstrated that extracellular CagA might induce IL-8 production by AGS cells.

Conclusion. Residues 303–456 of the N-terminal region of CagA induce IL-8 production via a CagA303-456–ITGB1–p38–IL-8 pathway, and ERK1/2 is also involved in the release of IL-8. Extracellular CagA might induce IL-8 production before translocation into AGS cells.

Network Pharmacology-Based Strategy to Investigate the Pharmacologic Mechanisms of Atractylodes macrocephala Koidz. for the Treatment of Chronic Gastritis

Chronic gastritis (CG) is an inflammatory disease. Atractylodes macrocephala Koidz (AMK) is employed in traditional Chinese medicine (TCM) to treat various disorders. AMK can be efficacious against CG, but the active ingredients, drug targets, and its exact molecular mechanism are not known. We employed network pharmacology to analyze the active ingredients, drug targets, and key pathways of AMK in CG treatment. Seventy-seven AMK candidate ingredients were selected from four databases, and 27 active ingredients were selected for CG treatment. Twenty-five overlapping gene symbols related to CG and drugs were obtained from GeneCards and OMIM databases. A protein–protein interaction (PPI) network and TCM comprehensive network (Drug–Ingredients–Gene symbols–Disease network) were constructed, and 528 Gene Ontology (GO) terms and 26 pathways were obtained by analyses of enrichment of GO pathways and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. We suggest that the interleukin-17 signaling pathway, C-type lectin receptor signaling pathway, tumor necrosis factor signaling pathway, and AGE-RAGE signaling pathway in diabetic complications might serve as the key points and principal pathways for CG treatment. We also evaluated the reliability of some important active ingredients and targets by in vitro experiments. We showed that AMK probably influences the inflammatory response, amino acid synthesis, and energy metabolism when treating CG. This study provides novel insights for researchers to explore the mechanism of action of TCM systematically.

The Microbiota and Pancreatic Cancer

Pancreatic cancer is one of the most lethal diseases. In pancreatic cancer development and progression, genetic (gene mutations and activation of oncogenes) and environmental factors (smoking, alcohol consumption, type 2 diabetes mellitus, obesity) play an essential role. Recently, molecular studies revealed that dysbiosis of microbiota also has influence on cancer development. Research indicates that bacteria and viruses can lead to chronic inflammation, antiapoptotic changes, cell survival, and cell invasion. This review presents bacteria and viruses oncogenic for the pancreas. Possible mechanisms of carcinogenic action are also described.

Significance of immunohistochemical overexpression of cyclooxygenase-2 in overall and disease-free survival of oral squamous cell carcinoma patients

OBJECTIVE

In Pakistan, oral cancer ranks as the most common malignancy in males and the second most common malignancy in females. Cyclooxygenase-2 has been explored as an agent of carcinogenesis in oral and other neoplasms. This study aimed to observe the expression of cyclooxygenase-2 in oral squamous cell carcinoma, and to correlate the expression with patients' clinical features and overall and disease-free survival.

METHODS

Immunohistochemistry for cyclooxygenase-2 was performed on a total of 100 oral squamous cell carcinoma formalin-fixed, paraffin-embedded blocks. Expression was correlated with patients' clinicopathological variables and overall and disease-free survival.

RESULTS

Cyclooxygenase-2 was overexpressed in 55 per cent of oral squamous cell carcinoma patients. Overexpression was correlated with overall survival (p = 0.013) and disease-free survival (p = 0.001) on univariate analysis. However, on multivariate analysis, cyclooxygenase-2 was associated with only disease-free survival (p = 0.044) and not overall survival (p = 0.208).

CONCLUSION

Expression of cyclooxygenase-2 is associated with poorer overall survival and higher rates of recurrence in oral squamous cell carcinoma patients.

Relationship between serum inflammatory cytokines and lifestyle factors in gastric cancer

Chronic inflammation is associated with increased risk of gastric cancer (GC), and GC risk is significantly associated with lifestyle. The aim of the present study was to explore the association between serum inflammatory cytokines and lifestyle factors in GC. A total of 20 serum inflammatory cytokines were measured in a hospital-based case-control population with 142 GC patients and 98 healthy controls. Controls without the selected healthy lifestyle factors were regarded as baseline, and correlation analysis was conducted to establish the association between serum inflammatory cytokines and lifestyle factors. The results demonstrated that several lifestyle factors (including eating fried and salty foods, eating quickly, smoking and drinking) could increase the risk of GC, while only eating fresh fruits could decrease the risk of GC. Correlation analysis revealed that increased serum interleukin (IL)-12/IL-23P40 levels was associated with GC risk as significant differences were observed in all lifestyle factors. Increased serum IL-8 was closely associated with smoking in GC patients, while increased IL-17α and IL-8 levels were associated with GC patients who ate salty foods. Increased IL-10 and decreased TGF-β levels were also associated with GC patients who ate fresh fruits. In conclusion, GC risk was strongly affected by lifestyle factors, which may regulate the expression of inflammatory cytokines and promote gastric carcinogenesis.

Association of Mannose-Binding Lectin rs1800450 and Tumor Necrotic Factor-α rs1800620 Polymorphism with Helicobacter pylori in Type II Diabetes Mellitus

Type II diabetes mellitus (T2DM) is the prevalent type of diabetes, including 90% of the cases world-wide. Helicobacter pylori plays a pathogenic role in the development of T2DM. The host genetic factors have a significant impact on the clinical outcome and anatomical distribution of H. pylori infection and polymorphisms in several genes such as tumor necrotic factor (TNF)-α and mannose-binding lectin (MBL) and are considered to increase the risk for the development of T2DM. In this study, we investigate the prevalence rate of H. pylori infection and its relationship to MBL rs1800450 and TNF-α rs1800620 polymorphism in T2DM. In this case-control study, 174 patients with type II diabetes and 185 healthy controls were studied. Also, demographics, physical, and biochemical parameters were performed in all patients. The DNA extracted from blood specimens was amplified by H. pylori cagA-specific primers. The MBL rs1800450 and TNF-α rs1800620 genotyping were detected by amplification refractory mutation system-polymerase chain reaction (ARMS-PCR). The results show that H. pylori cagA positivity was detected in 42.82% of the diabetic patients and in 22.16% of the control group, and H. pylori infection was closely correlated with MBL rs1800450 AA genotype and TNF-α rs1800620 GG genotype when compared with healthy controls. Furthermore, these two genotypes were strongly associated with H. pylori cagA(+) samples when compared with cagA(-) samples. In addition, the presence of H. pylori cagA(+) infection was significantly associated with the elevated serum levels of total cholesterol and low-density lipoprotein cholesterol. In general, it can be concluded that molecular analysis of MBL rs1800450 AA genotype and TNF-α rs1800620 AA genotype is important in the early detection and treatment of T2DM with H. pylori cagA(+) infection.

Native and bone marrow-derived cell mosaicism in gastric carcinoma in H. pylori-infected p27-deficient mice

Objective

Chronic Helicobacter pylori (H. pylori) infection promotes non-cardia gastric cancer. Some mouse models suggest that bone marrow derived cells (BMDC) contribute to Helicobacter-associated gastric carcinogenesis. We determined whether this increased susceptibility to Helicobacter-induced gastric carcinogenesis of p27-deficient mice is dependent upon their p27-null BMDC or their p27-null gastric epithelial cells.

Design

Female mice (recipients) were irradiated and transplanted with BMDC from male donors. Wild type (WT) mice in group 1 (control) received BMDC from male GFP-transgenic mice. Female WT and p27 KO mice were engrafted with male p27KO mice BMDC (Group 2) or GFP-transgenic WT BMDC (Group 3). Recipients were infected with H. pylori SS1 for one year.

Results

Mice lacking p27 in either the BM pool or gastric epithelium developed significantly more advanced gastric pathology, including high-grade dysplasia. Co-staining of donor BMDC in dysplastic gastric glands was confirmed by immunofluorescence. Gastric expression of IL-1 beta protein was reduced in groups 2 and 3 (p < 0.05 vs control) whereas expression of IFN-γ and chemokines MIP-1 beta, MIG, IP-10 and RANTES in group 2 were significantly higher than group 3.

Conclusions

Both bone marrow-derived and gastric epithelial cells contribute to the increased gastric cancer susceptibility of p27-deficient H. pylori-infected mice.

Effect of Helicobacter pylori infection on chronic periodontitis by the change of microecology and inflammation

Helicobacter pylori (H. pylori), a pathogen inducing peptic disease, is recently found to be binding to the progress of periodontitis. Most previous studies are case-controlled, and they investigate the risk of H. pylori infection in disease the development of while few studies evaluate the correlation between H. pylori and periodontal pathogens. Therefore, we investigated the correlation between H. pylori infection with periodontal parameters, periodontal pathogens and inflammation. The results indicated that patients with H. pylori showed significantly higher probing depth and attachment loss than those without (p < 0.05). Among 28 subgingival plaque samples from 14 patients, the frequencies of Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum and Treponema denticola were significantly higher with H. pylori infection than those without H. pylori infection (p < 0.05). However, the frequency of Aggregatibacter actinomycetemcomitans was lower (p < 0.05). Furthermore, after human acute monocytic leukemia cell line (THP-1) was stimulated with cagA-positive standard strains (cagA⁺ H. pylori 26695), the expression of periodontitis-related molecules Wnt5a, interleukin 8 (IL-8), interleukin 6 (IL-6) and interferon gamma (IFN-γ) significantly increased (p < 0.05). Conversely, the expression of tumor necrosis factor alpha (TNF-α) was almost stable. Meanwhile, cagA⁺ H. pylori promoted significantly higher expression of IL-8 and Wnt5a than isogenic cagA mutants strains (cagA⁻ H. pylori 26695) did. Taken together, our data suggested that H. pylori might promote the growth of some periodontal pathogens and aggravate the progress of chronic periodontitis.

Blueberry Metabolites Attenuate Lipotoxicity-Induced Endothelial Dysfunction

SCOPE

Lipotoxicity-induced endothelial dysfunction is an important vascular complication associated with diabetes. Clinical studies support the vascular benefits of blueberry anthocyanins, but the underlying mechanism is unclear. The hypothesis that metabolites of blueberry anthocyanins attenuate lipotoxicity-induced endothelial dysfunction was tested.

METHODS AND RESULTS

Human aortic endothelial cells (HAECs) were treated for 6 h with either: (i) the parent anthocyanins (malvidin-3-glucoside and cyanidin-3-glucoside); or (ii) the blueberry metabolites (hydroxyhippuric acid, hippuric acid, benzoic acid-4-sulfate, isovanillic acid-3-sulfate, and vanillic acid-4-sulfate), at concentrations known to circulate in humans following blueberry consumption. For the last 5 h HAECs were treated with palmitate or vehicle. HAECs treated with palmitate displayed elevated reactive oxygen species generation, increased mRNA expression of NOX4, chemokines, adhesion molecules, and IκBα, exaggerated monocyte binding, and suppressed nitric oxide production. Of note, the damaging effects of palmitate were ameliorated in HAECs treated with blueberry metabolites but not parent anthocyanins. Further, important translational relevance of these results was provided by our observation that palmitate-induced endothelial dysfunction was lessened in arterial segments that incubated concurrently with blueberry metabolites.

CONCLUSION

The presented findings indicate that the vascular benefits of blueberry anthocyanins are mediated by their metabolites. Blueberries might complement existing therapies to lessen vascular complications.

CD4+ regulatory T cells in gastric cancer mucosa are proliferating and express high levels of IL-10 but little TGF-β

BACKGROUND

An increase of regulatory T cells, defined as CD25^high- and/or FOXP3⁺-expressing CD4⁺ T cells, within tumors has been reported in several studies. Tregs promote tumor growth by modulating the antitumor immune response, mainly through inhibition of T-cell-mediated tumor cell killing: this has been suggested to be dependent on IL-10 and/or TGF-β. In stomach cancer, the mechanisms behind the accumulation of Tregs in tumor tissue has not been fully elucidated, and neither has Treg gene expression in situ.

MATERIALS AND METHODS

Stomach tissue from gastric cancer patients undergoing gastric resection was analyzed using flow cytometry and cell sorting, followed by RT-PCR.

RESULTS

We observed that stomach CD4⁺ FOXP3⁺ T cells proliferated to a higher degree than CD4⁺ FOXP3^- T cells, which may contribute to Treg accumulation in the mucosa. By analyzing DNA methylation, we demonstrated that both proliferating and nonproliferating FOXP3⁺ T cells exhibited complete demethylation of the FOXP3 gene, indicating a stable FOXP3 expression in both cell populations. Furthermore, analysis of T-cell populations isolated directly from the tumor and tumor-free mucosa demonstrated that CD4⁺ CD25^high T cells have a higher IL-10/IFN-γ gene expression ratio but express lower levels of TGF-β than CD4⁺ CD25^low/- T cells.

CONCLUSION

We demonstrate strong proliferation among regulatory CD4⁺ FOXP3⁺ CD25^high T cells in the gastric cancer mucosa. These local Treg express a suppressive cytokine profile characterized by high IL-10 and low TGF-β and IFN-γ production.

The Effect of Probiotic Plus Prebiotic Supplementation on the Tolerance and Efficacy of Helicobacter Pylori Eradication Quadruple Therapy: a Randomized Prospective Double Blind Controlled Trial

BACKGROUND

Standard anti-Helicobacter pylori (H. pylori) treatment fails in the eradication of the organism in almost 10-35% of the patients and has different side effects. Recent studies have proposed that probiotic supplementations with or without prebiotic may improve the eradication rate and diminish the side effects, although it is still a controversial issue. We aimed to investigate the effect of probiotic with prebiotic supplementation on the eradication rate and side effects of anti H. pylori quadruple therapy.

METHODS

76 patients with a positive biopsy specimen for H. pylori were enrolled. They were randomized to receive quadruple therapy of bismuth, clarithromycin, amoxicillin, and omeprazole for 14 days and also the synbiotic or the placebo. We asked them to answer study questionnaires at the beginning and during the treatment. Finally, urea breath test was done 8 weeks after the treatment.

RESULTS

The eradication rate was significantly better in the synbiotic group by intention-to-treat analysis (p<0.05). Treatment side effects such as diarrhea, nausea, vomiting, epigastric pain, flatulence, constipation, and taste abnormality were similar in both groups but anorexia was significantly better in the synbiotic group (p <0.05).

CONCLUSION

The eradication rate was significantly better in the synbiotic group by intention-to-treat analysis (p<0.05). Treatment side effects such as diarrhea, nausea, vomiting, epigastric pain, flatulence, but could improve the eradication by augmenting the treatment tolerance and compliance.

Effect of interleukin-1β and tumor necrosis factor α gene silencing on mouse gastric cancer cell proliferation and migration

The aim of the present study was to investigate the effect of interleukin-1β (IL-1β) and tumor necrosis factor α (TNFα) gene co-silencing in mouse gastric cancer (GC) cells. Respectively, three pairs of liposome-encapsulated IL-1β and TNFα small interfering RNA (siRNA) were transfected into the mouse GC cell line MFC. The most effective siRNA, as identified by reverse transcription-polymerase chain reaction, was used for co-suppression of IL-1β and TNFα genes. The activities of cell proliferation, colony formation and migration were determined by the Cell Counting Kit 8 method, colony formation assay and Transwell assay, respectively. Protein array analysis was performed to identify the differentially expressed factors. The possible signaling pathways of the various factors targeting the genes were identified by pathway enrichment analysis using KOBAS 2.0. siRNA1 and siRNAc were the most effective interference sequences for IL-1β and TNFα, respectively. Following co-transfection of siRNA1 and siRNAc, the expression of IL-1β and TNFα was inhibited at the mRNA and protein levels, and the cell proliferation, colony forming and migration abilities were reduced (P<0.05). The expression of inflammatory factors, including chemokine ligand 5, cyclooxygenase-2, IL-6, transforming growth factor β, IL-17A, matrix metallopeptidase 9 and stromal cell-derived factor 1α were also inhibited (P<0.05). These factors are mainly involved in the rheumatoid arthritis pathway, the intestinal immune network for IgA production, the TNF signaling pathway and the inflammatory bowel disease pathway. IL-1β and TNFα gene silencing inhibits the proliferation and migration of MFC. The mechanisms may involve multiple inflammatory factors that participate in the signaling pathways of tumor tissue inflammation, the immune network and TNF.

Lack of association among TNF-α gene expression, -308 polymorphism (G > A) and virulence markers of Helicobacter pylori

Background

Tumor necrosis factor plays a critical role in the pathogenesis of gastric diseases such as gastric cancer, and an abnormal inflammatory response has frequently been observed in dyspeptic patients. Helicobacter pylori infection can induce a gastric mucosal inflammatory response that may be influenced by -308 (G > A) polymorphisms and gene expression of the TNF-α gene.

Methods

One hundred and thirty-four gastric biopsy samples were collected from patients of both genders (61♂ and 73♀, mean age 40.3 ± 24.2 years) with gastric symptoms. The -308 (G > A) polymorphism of TNF-α was characterized using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). The expression level was measured using real-time PCR, and relative quantification (RQ) was calculated using the comparative CT method (2^-ΔΔCT).

Results

The analysis revealed an increase in TNF-α gene expression in patients with gastritis; on the other hand, no statistical differences were observed in patients with gastric cancer. In addition, no association was found among -308 polymorphism genotypes, virulence markers, or TNF-α gene expression.

Conclusions

Helicobacter pylori induces a large increase in TNF-α expression in patients with gastritis, regardless of tissue inflammation, but after the tissue becomes neoplastic, the presence of bacteria did not influence expression. These results suggest that the TNF-α pathway may play an important role in the progression from gastritis to gastric cancer

Expression and clinical significance of cyclooxygenase-2 and interleukin-32 in primary gastric B-cell lymphoma

Cyclooxygenase-2 (COX-2) and interleukin-32 (IL-32) expression has been examined in various carcinomas and inflammations, and has been suggested to be significant in tumor progression and prognosis. The present study was conducted to investigate the expression of COX-2 and IL-32 in primary gastric B-cell lymphoma in order to define their clinical significance and their association with Helicobacter pylori (Hp) infection. COX-2 and IL-32 protein expression was detected in 31 primary gastric B-cell lymphoma patients and 19 chronic gastritis patients with immunohistochemistry. COX-2 and IL-32 expression was significantly higher in primary gastric lymphoma (PGL) tissues compared with gastritis tissues (51.6 vs. 21.1% for COX-2, P=0.032; and 58.1 vs. 26.3% for IL-32, P=0.029) and was significantly higher in Hp⁺ lymphoma tissues compared with Hp^- lymphoma tissues (66.7 vs. 20% for COX-2, P=0.015; and 71.4 vs. 30% for IL-32, P=0.029). In the PGL tissues, the expression level of COX-2 was positively correlated with the expression level of IL-32, and the two were each positively correlated with Hp infection (P=0.004 for COX-2 and IL-32; P=0.01 for COX-2 and Hp infection; and P=0.003 for IL-32 and Hp infection). COX-2 expression was found to be significantly associated (P<0.05) with an aggressive tumor type, higher expression of Ki-67, frequent lymph node metastasis and advanced stage. IL-32 expression was found to be significantly correlated (P<0.05) with frequent lymph node metastasis and an advanced stage. The survival time was longer in the COX-2^- and IL-32^- lymphoma patients compared with the COX-2⁺ and IL-32⁺ lymphoma patients, but these differences were not statistically significant. These results suggested that Hp infection and the expression of COX-2 and IL-32 were closely linked with each other, and that the overexpression of COX-2 and IL-32 was correlated with tumor progression in primary gastric B-cell lymphoma, thus indicating potential novel therapeutic target.

Helicobacter pylori cytotoxin-associated gene A activates tumor necrosis factor-α and interleukin-6 in gastric epithelial cells through P300/CBP-associated factor-mediated nuclear factor-κB p65 acetylation

Helicobacter pylori‑initiated chronic gastritis is characterized by the cytotoxin‑associated gene (Cag) pathogenicity island‑dependent upregulation of pro‑inflammatory cytokines in gastric epithelial cells, which is largely mediated by the activation of nuclear factor (NF)‑κB as a transcription factor. However, the precise regulation of NF‑κB activation, particularly post‑translational modifications in the CagA‑induced inflammatory response, has remained elusive. The present study showed that Helicobacter pylori CagA, an important virulence factor, induced the expression of P300/CBP‑associated factor (PCAF) in gastric epithelial cells. Further study revealed that PCAF was able to physically associate with the NF‑κB p65 sub‑unit and enhance its acetylation. More importantly, PCAF‑induced p65 acetylation was shown to contribute to p65 phosphorylation and further upregulation of tumor necrosis factor (TNF)‑α and interleukin (IL)‑6 in gastric adenocarcinoma cells. In conclusion, the results of the present study indicated that Helicobacter pylori CagA enhanced TNF‑α and IL‑6 in gastric adenocarcinoma cells through PCAF‑mediated NF‑κB p65 sub‑unit acetylation.

Association between Helicobacter pylori genotypes and severity of chronic gastritis, peptic ulcer disease and gastric mucosal interleukin-8 levels: Evidence from a study in the Middle East

Background

The varied clinical presentations of Helicobacter pylori (H. pylori) infection are most likely due to differences in the virulence of individual strains, which determines its ability to induce production of interleukin-8 (IL-8) in the gastric mucosa. The aim of this study was to examine association between cagA, vacA-s1 and vacA-s2 genotypes of H. pylori and severity of chronic gastritis and presence of peptic ulcer disease (PUD), and to correlate these with IL-8 levels in the gastric mucosa.

Methods

Gastric mucosal biopsies were obtained from patients during esophagogastroduodenoscopy. The severity of chronic gastritis was documented using the updated Sydney system. H. pylori cagA and vacA genotypes were detected by PCR. The IL-8 levels in the gastric mucosa were measured by ELISA.

Results

H. pylori cagA and/or vacA genotypes were detected in 99 patients (mean age 38.4±12.9; 72 males), of whom 52.5% were positive for cagA, 44.4% for vacA-s1 and 39.4% for vacA-s2; and 70.7% patients had PUD. The severity of inflammation in gastric mucosa was increased with vacA-s1 (p=0.017) and decreased with vacA-s2 (p=0.025), while cagA had no association. The degree of neutrophil activity was not associated with either cagA or vacA-s1, while vacA-s2 was significantly associated with decreased neutrophil activity (p=0.027). PUD was significantly increased in patients with cagA (p=0.002) and vacA-s1 (p=0.031), and decreased in those with vacA-s2 (p=0.011). The level of IL-8 was significantly increased in patients with cagA (p=0.011) and vacA-s1 (p=0.024), and lower with vacA-s2 (p=0.004). Higher levels of IL-8 were also found in patients with a more severe chronic inflammation (p=0.001), neutrophil activity (p=0.007) and those with PUD (p=0.001).

Conclusions

Presence of vacA-s1 genotype of H. pylori is associated with more severe chronic inflammation and higher levels of IL-8 in the gastric mucosa, as well as higher frequency of PUD. Patients with vacA-s2 have less severe gastritis, lower levels of IL-8, and lower rates of PUD. The presence of cagA genotype is not associated with the severity of gastritis or IL-8 induction in the gastric mucosa. The association of cagA with PUD may be a reflection of its presence with vacA-s1 genotype.

Abnormal COX2 protein expression may be correlated with poor prognosis in oral cancer: a meta-analysis

Background. The prognostic significance of COX2 for survival of patients with oral cancer remains controversial. Thus, the meta-analysis was performed in order to identify COX2 expression impact on prognosis of oral cancer. Method. Relevant literatures were searched using the following electronic databases without any language restrictions: Web of Science, the Cochrane Library Database, PubMed, EMBASE, CINAHL, and CBM. Version 12.0 STATA software (Stata Corporation, College Station, Texas, USA) was used for the current meta-analysis. Odds ratios (ORs) and hazard ratios (HRs) with their corresponding 95% confidence interval (95% CI) were also calculated to clarify the correlation between COX2 expression and prognosis of oral cancer. Results. Final analysis of 979 oral cancer patients from 12 clinical cohort studies was performed. The meta-analysis results show that COX2 expression in cancer tissues was significantly higher than those in normal and benign tissues (all P < 0.05). Combined HR of COX2 suggests that positive COX2 expression has a shorter overall survival (OS) than those of negative COX2 expression (P < 0.05). Conclusion. The meta-analysis study shows that elevated COX2 expression may be associated with the pathogenesis of oral cancer and with a worse prognosis in oral cancer patients.

Helicobacter pylori infection: host immune response, implications on gene expression and microRNAs

Helicobacter pylori (H. pylori) infection is the most common bacterial infection worldwide. Persistent infection of the gastric mucosa leads to inflammatory processes and may remain silent for decades or progress causing more severe diseases, such as gastric adenocarcinoma. The clinical consequences of H. pylori infection are determined by multiple factors, including host genetic predisposition, gene regulation, environmental factors and heterogeneity of H. pylori virulence factors. After decades of studies of this successful relationship between pathogen and human host, various mechanisms have been elucidated. In this review, we have made an introduction on H. pylori infection and its virulence factors, and focused mainly on modulation of host immune response triggered by bacteria, changes in the pattern of gene expression in H. pylori-infected gastric mucosa, with activation of gene transcription involved in defense mechanisms, inflammatory and immunological response, cell proliferation and apoptosis. We also highlighted the role of bacteria eradication on gene expression levels. In addition, we addressed the recent involvement of different microRNAs in precancerous lesions, gastric cancer, and inflammatory processes induced by bacteria. New discoveries in this field may allow a better understanding of the role of major factors involved in the pathogenic mechanisms of H. pylori.

Roles of proinflammatory cytokines in precancerous lesions of gastric cancer

Precancerous lesions of gastric cancer, including intestinal metaplasia and dysplasia, are important stages in the evolution from normal gastric tissue to gastric cancer. Gastric cancer has a very high mortality rate, mainly due to post-metastasis diagnosis. Therefore, diagnosis of precancerous lesions of gastric cancer is of great clinical significance. In recent years, it has been reported that some proinflammatory cytokines such as interleukin 1β (IL-1β), IL-8, IL-11, tumor necrosis factor α (TNF-α) and interferon-gamma (IFN-γ) play important roles in the development of precancerous lesions of gastric cancer. A more detailed understanding of the roles of proinflammatory cytokines may provide new therapeutic targets for precancerous lesions of gastric cancer. Here, we summarize the roles of some proinflammatory cytokines in the progression of precancerous lesions of gastric cancer.

Non-microbial approach for Helicobacter pylori as faster track to prevent gastric cancer than simple eradication

Although the International Agency for Research on Cancer declared Helicobacter pylori (H. pylori) as a definite human carcinogen in 1994, the Japanese Society for Helicobacter Research only recently (February 2013) adopted the position that H. pylori infection should be considered as an indication for either amelioration of chronic gastritis or for decreasing gastric cancer mortality. Japanese researchers have found that H. pylori eradication halts progressive mucosal damage and that successful eradication in patients with non-atrophic gastritis most likely prevents subsequent development of gastric cancer. However, those who have already developed atrophic gastritis/gastric atrophy retain potential risk factors for gastric cancer. Because chronic perpetuated progression of H. pylori-associated gastric inflammation is associated with increased morbidity culminating in gastric carcinogenesis, a non-microbial approach to treatment that provides long-term control of gastric inflammation through nutrients and other interventions may be an effective way to decrease this morbidity. This non-microbial approach might represent a new form of prerequisite "rescue" therapy that provides a quicker path to the prevention of gastric cancer as compared to simple eradication.

Up-regulation of CLDN1 in gastric cancer is correlated with reduced survival

Background

The genetic changes in gastric adenocarcinoma are extremely complex and reliable tumor markers have not yet been identified. There are also remarkable geographical differences in the distribution of this disease. Our aim was to identify the most differentially regulated genes in 20 gastric adenocarcinomas from a Norwegian selection, compared to matched normal mucosa, and we have related our findings to prognosis, survival and chronic Helicobacter pylori infection.

Methods

Biopsies from gastric adenocarcinomas and adjacent normal gastric mucosa were obtained from 20 patients immediately following surgical resection of the tumor. Whole genome, cDNA microarray analysis was performed on the RNA isolated from the sample pairs to compare the gene expression profiles between the tumor against matched mucosa. The samples were microscopically examined to classify gastritis. The presence of H. pylori was examined using microscopy and immunohistochemistry.

Results

130 genes showed differential regulation above a predefined cut-off level. Interleukin-8 (IL-8) and Claudin-1 (CLDN1) were the most consistently up-regulated genes in the tumors. Very high CLDN1 expression in the tumor was identified as an independent and significant predictor gene of reduced post-operative survival. There were distinctly different expression profiles between the tumor group and the control mucosa group, and the histological subsets of mixed type, diffuse type and intestinal type cancer demonstrated further sub-clustering. Up-regulated genes were mapped to cell-adhesion, collagen-related processes and angiogenesis, whereas normal intestinal functions such as digestion and excretion were associated with down-regulated genes. We relate the current findings to our previous study on the gene response of gastric epithelial cells to H. pylori infection.

Conclusions

CLDN1 was highly up-regulated in gastric cancer, and CLDN1 expression was independently associated with a poor post-operative prognosis, and may have important prognostic value. IL-8 and CLDN1 may represent central links between the gene response seen in acute H. pylori infection of gastric epithelial cells, and ultimately gastric cancer.

Gastric cancer-molecular and clinical dimensions

Gastric cancer imposes a considerable health burden around the globe despite its declining incidence. The disease is often diagnosed in advanced stages and is associated with a poor prognosis for patients. An in-depth understanding of the molecular underpinnings of gastric cancer has lagged behind many other cancers of similar incidence and morbidity, owing to our limited knowledge of germline susceptibility traits for risk and somatic drivers of progression (to identify novel therapeutic targets). A few germline (PLCE1) and somatic (ERBB2, ERBB3, PTEN, PI3K/AKT/mTOR, FGF, TP53, CDH1 and MET) alterations are emerging and some are being pursued clinically. Novel somatic gene targets (ARID1A, FAT4, MLL and KMT2C) have also been identified and are of interest. Variations in the therapeutic approaches dependent on geographical region are evident for localized gastric cancer-differences that are driven by preferences for the adjuvant strategies and the extent of surgery coupled with philosophical divides. However, greater uniformity in approach has been noted in the metastatic cancer setting, an incurable condition. Having realized only modest successes, momentum is building for carrying out more phase III comparative trials, with some using biomarker-based patient selection strategies. Overall, rapid progress in biotechnology is improving our molecular understanding and can help with new drug discovery. The future prospects are excellent for defining biomarker-based subsets of patients and application of specific therapeutics. However, many challenges remain to be tackled. Here, we review representative molecular and clinical dimensions of gastric cancer.

Gastric cancer-molecular and clinical dimensions

Gastric cancer imposes a considerable health burden around the globe despite its declining incidence. The disease is often diagnosed in advanced stages and is associated with a poor prognosis for patients. An in-depth understanding of the molecular underpinnings of gastric cancer has lagged behind many other cancers of similar incidence and morbidity, owing to our limited knowledge of germline susceptibility traits for risk and somatic drivers of progression (to identify novel therapeutic targets). A few germline (PLCE1) and somatic (ERBB2, ERBB3, PTEN, PI3K/AKT/mTOR, FGF, TP53, CDH1 and MET) alterations are emerging and some are being pursued clinically. Novel somatic gene targets (ARID1A, FAT4, MLL and KMT2C) have also been identified and are of interest. Variations in the therapeutic approaches dependent on geographical region are evident for localized gastric cancer-differences that are driven by preferences for the adjuvant strategies and the extent of surgery coupled with philosophical divides. However, greater uniformity in approach has been noted in the metastatic cancer setting, an incurable condition. Having realized only modest successes, momentum is building for carrying out more phase III comparative trials, with some using biomarker-based patient selection strategies. Overall, rapid progress in biotechnology is improving our molecular understanding and can help with new drug discovery. The future prospects are excellent for defining biomarker-based subsets of patients and application of specific therapeutics. However, many challenges remain to be tackled. Here, we review representative molecular and clinical dimensions of gastric cancer.

Association of Helicobacter pylori babA2 with peptic ulcer disease and gastric cancer

AIM: To investigate the association between babA2 gene and peptic ulcer disease (PUD) and gastric cancer (GC) in Helicobacter pylori-infected populations.

METHODS: We evaluated the relationship between babA2 and clinical outcomes (PUD and GC) using a meta-analysis. A literature search was performed using the PubMed and Web of Science databases for relevant case-control studies that met the defined inclusion criteria. The ORs and 95%CIs were calculated to estimate the association between babA2 genotype and clinical outcomes. A fixed-effect or random-effect model was performed depending on the absence or presence of significant heterogeneity.

RESULTS: A total of 25 articles with 38 studies met the inclusion criteria and were finally included in this meta-analysis. The results showed that the babA2 genotype was significantly associated with an increased risk of PUD (OR = 2.069, 95%CI: 1.530-2.794, P < 0.001) and especially in the subgroup of duodenal ulcer (OR = 1.588, 95%CI: 1.141-2.209, P = 0.006). Moreover, a significant association between babA2 gene and PUD and duodenal ulcer (OR = 2.739, 95%CI: 1.860-4.032, P < 0.001; OR = 2.239, 95%CI: 1.468-3.415, P < 0.001, respectively) was observed in western countries but not in Asian countries.

CONCLUSION: We demonstrated that the presence of babA2 may be associated with increased risks for PUD, especially duodenal ulcer, in western countries.

Helicobacter pylori promotes apoptosis, activates cyclooxygenase (COX)-2 and inhibits heat shock protein HSP70 in gastric cancer epithelial cells

OBJECTIVE

Apoptosis plays an important role in the regulation of gastric epithelial cell number and gastrointestinal disorders induced by Helicobacter pylori (Hp). Heat shock proteins (HSPs) are involved in cell integrity, cell growth and in gastric mucosa colonized by Hp. COX-2 was implicated in Hp-induced carcinogenesis but the effects of this germ and CagA cytotoxin on HSP70, COX-2, Bax and Bcl-2 in gastric cancer epithelial cells have been little studied.

MATERIAL AND METHODS

We determined the expression for HSP70, Bax and Bcl-2 in human gastric epithelial MKN7 cells incubated with live strain Hp (cagA + vacA+) with or without co-incubation with exogenous CagA and NS-398, the selective COX-2 inhibitor. After 3-48 h of incubation, the expression of HSP70, COX-2, Bax and Bcl-2 mRNA and proteins were determined by RT-PCR and immunoprecipitation.

RESULTS

Hp inhibited expression for HSP70 and this was significantly potentiated by exogenous CagA. Co-incubation of epithelial cells with Hp, without or with CagA increased Bax expression and simultaneously decreased expression for Bcl-2. The increase in COX-2 mRNA and Bax expression were significantly inhibited by NS-398. We conclude that Hp promotes apoptosis in adenocarcinoma gastric epithelial cells in vitro and this is associated with activation of COX-2 and inhibition of HSP70.

Epigallocatechin gallate reduces vascular inflammation in db/db mice possibly through an NF-κB-mediated mechanism

SCOPE

Hyperglycemia-induced vascular inflammation resulting in the adhesion of monocytes to endothelium is a key event in the pathogenesis of atherosclerosis in diabetes. We investigated whether epigallocatechin gallate (EGCG), a major catechin found in green tea, reduces vascular inflammation in diabetes.

METHODS AND RESULTS

Human aortic endothelial cells (HAEC) were pretreated with green tea catechins before the addition of high glucose (25 mM) for 72 h. EGCG at physiologically achievable concentration (1 μM) significantly inhibited high glucose induced adhesion of monocytes to HAEC both in static and under flow conditions. EGCG also reduced nuclear factor κB (NF-κB) regulated transcriptional activity in ECs. Six-week-old diabetic db/db mice were fed a diet containing 0% or 0.1% EGCG for 8 weeks. ECs were isolated from aortic vessels of db/db, db/db-EGCG, and control db/+ mice. EGCG supplementation greatly suppressed diabetes-increased monocytes adhesion to ECs, which is associated with reduced circulating levels of chemokines, and reduced secretions of chemokines and adhesion molecules by aortic ECs from db/db-EGCG mice. EGCG treatment reduced nuclear translocation of NF-κB p65 in aortic vessels, decreased blood pressure and serum concentrations of cholesterol and triglycerides in db/db-EGCG mice.

CONCLUSION

EGCG may have a direct protective effect against vascular inflammation in diabetes.

Helicobacter pylori iceA, clinical outcomes, and correlation with cagA: a meta-analysis

Background

Although the iceA (induced by contact with epithelium) allelic types of Helicobacter pylori have been reported to be associated with peptic ulcer, the importance of iceA on clinical outcomes based on subsequent studies is controversial. The aim of this study was to estimate the magnitude of the risk for clinical outcomes associated with iceA.

Methods

A literature search was performed using the PubMed and EMBASE databases for articles published through April 2011. Published case-control studies examining the relationship between iceA and clinical outcomes (gastritis, peptic ulcer, including gastric ulcer and duodenal ulcer, and gastric cancer) were included.

Results

Fifty studies with a total of 5,357 patients were identified in the search. Infection with iceA1-positive H. pylori increased the overall risk for peptic ulcer by 1.26-fold (95% confidence interval [CI], 1.09–1.45). However, the test for heterogeneity was significant among these studies. Sensitivity analysis showed that the presence of iceA1 was significantly associated with peptic ulcer (odds ratio [OR] = 1.25, 95% CI = 1.08–1.44). The presence of iceA2 was inversely associated with peptic ulcer (OR = 0.76, 95% CI = 0.65–0.89). The presence of iceA was not associated with gastric cancer. Most studies examined the cagA status; however, only 15 studies examined the correlation and only 2 showed a positive correlation between the presence of cagA and iceA1.

Conclusion

Our meta-analysis confirmed the importance of the presence of iceA for peptic ulcer, although the significance was marginal.

Circulating interleukin-27 levels in Helicobacter pylori-infected patients with gastric or duodenal ulcers, independent of the bacterial cytotoxin-associated gene A virulence factor

OBJECTIVE

The aim was to evaluate the interleukin (IL)-27 levels in Helicobacter pylori (H. pylori)-infected patients with gastric ulcer (GU) or duodenal ulcer (DU) and to determine its association with H. pylori virulence factor cytotoxin-associated gene A (CagA).

METHODS

In all, 127 H. pylori infected patients (including 96 DU patients, of whom 61 were anti-CagA(+) and 35 were anti-CagA(-)) and 31 GU patients (of whom 15 were anti-CagA(+) and 16 were anti-CagA(-)), 60 asymptomatic (AS) carriers (of whom 30 were anti-CagA(+) and 30 were anti-CagA(-)) and 30 healthy H. pylori-negative participants (as a control) were enrolled in the study. Serum concentrations of IL-27 were measured by the enzyme-linked immunosorbent assay method.

RESULTS

The mean levels of IL-27 in the GU (44.26 ± 7.12 pg/mL) and DU patients (40.84 ± 3.90 pg/mL) was significantly higher than those observed in the AS carriers (22.06 ± 1.90 pg/mL, P < 0.001) and the control group (18.12 ± 1.68 pg/mL, P < 0.001 and P < 0.002, respectively). In the GU, DU and AS groups the levels of IL-27 in anti-CagA(+) participants were not significantly differ from that in the anti-CagA(-) participants.

CONCLUSIONS

These results showed that the mean concentration of IL-27 in H. pylori-infected peptic ulcer (PU) patients was higher than in AS carriers and the healthy control group. The serum concentrations of IL-27 were not affected by the CagA factor.

Difluoromethylornithine is a novel inhibitor of Helicobacter pylori growth, CagA translocation, and interleukin-8 induction

Helicobacter pylori infects half the world's population, and carriage is lifelong without antibiotic therapy. Current regimens prescribed to prevent infection-associated diseases such as gastroduodenal ulcers and gastric cancer can be thwarted by antibiotic resistance. We reported that administration of 1% d,l-α-difluoromethylornithine (DFMO) to mice infected with H. pylori reduces gastritis and colonization, which we attributed to enhanced host immune response due to inhibition of macrophage ornithine decarboxylase (ODC), the rate-limiting enzyme in polyamine biosynthesis. Although no ODC has been identified in any H. pylori genome, we sought to determine if DFMO has direct effects on the bacterium. We found that DFMO significantly reduced the growth rate of H. pylori in a polyamine-independent manner. Two other Gram-negative pathogens possessing ODC, Escherichia coli and Citrobacter rodentium, were resistant to the DFMO effect. The effect of DFMO on H. pylori required continuous exposure to the drug and was reversible when removed, with recovery of growth rate in vitro and the ability to colonize mice. H. pylori exposed to DFMO were significantly shorter in length than those untreated and they contained greater internal levels of ATP, suggesting severe effects on bacterial metabolism. DFMO inhibited expression of the H. pylori virulence factor cytotoxin associated gene A, and its translocation and phosphorylation in gastric epithelial cells, which was associated with a reduction in interleukin-8 expression. These findings suggest that DFMO has effects on H. pylori that may contribute to its effectiveness in reducing gastritis and colonization and may be a useful addition to anti-H. pylori therapies.

Combination of Helicobacter pylori-iceA2 and proinflammatory interleukin-1 polymorphisms is associated with the severity of histological changes in Venezuelan chronic gastritis patients

Helicobacter pylori is a major cause of chronic gastritis (CG) and a firmly established carcinogen for gastric adenocarcinoma. However, the underlying pathogenic mechanisms are not fully understood. In this work we studied the association of the allelic variation of H. pylori-iceA virulence factor and human proinflammatory interleukin (IL)-1 polymorphisms (IL-1B-31, IL-1B-511, IL-1B+3954 and IL-1RN) with histopathological changes in the gastric mucosa of patients with CG in Venezuela, a country with a high incidence of and mortality from gastric cancer. Although in this work the iceA1 allele was found more frequently (69.7%), iceA2 allele prevalence was higher in samples with atrophic gastritis (AG) and more severe grades of granulocytic (G2/G3) [P=0.02; odds ratio (OR) 3.3] and lymphocytic infiltration (L2/L3). The carriage of iceA2 strains combined with proinflammatory IL-1 polymorphisms IL-1-31C or IL-1-511T allele carrier genotypes increased even more the risk of presenting G2/G3 with ORs of 5.1 and 5.4, respectively. Moreover, the iceA2/IL-1B-511T and iceA2/IL-1B-31C/-511T/IL-1RN(*)2 bacteria/host genotype combinations showed a significant association with AG and L2/L3, respectively. Despite not being well established, the bacterial risk factor iceA2 seems an important predictor of severe histological changes in CG, separately or in combination with host genetic factors in the Venezuelan population.

Methylation status of CDH1 gene in samples of gastric mucous from brazilian patients with chronic gastritis infected by Helicobacter pylori

CONTEXT: Gastric cancer is one of the top list of cancer types that most leads to death in Brazil and worldwide. Helicobacter pylori(H. pylori) is a class I carcinogen and infect almost 90% of chronic gastritis patients. Some genotypes confer different virulent potential to H. pylori and can increase the risk of gastritis development. Methylation of CpG islands can inactivate tumor suppressor genes and therefore, it can be involved in the tumorigenic process. CDH1 is a tumor suppressor gene that encodes the E-cadherin protein, which is important in maintaining cell-cell contacts. The inactivation of this gene can increase the chance of metastasis. Promoter methylation of CDH1 at early steps of gastric carcinogenesis is not yet completely understood. OBJECTIVE: In this study, we investigated the methylation status of CDH1 in chronic gastritis samples and correlated it with the presence of H. pylori. METHODS: Sixty gastric mucosal biopsies were used in this study. The detection of H. pylori was performed with the PCR primers specific to urease C gene. H. pylori genotyping was performed by PCR to cagA and vacA (s and m region). The methylation status of these gene CDH1 was analyzed using methylation-specific polymerase chain reaction and direct sequencing of the PCR products was performed using primers methylated and unmethylated in both forward and reverse directions. RESULTS: H. pylori was detected in 90% of chronic gastritis samples; among these 33% were cagA positive and 100% vacA s1. The genotype vacA s2/m1 was not detected in any sample analyzed. Methylation of CDH1 was detected in 63.3% of chronic gastritis samples and 95% of them were also H. pylori-positive. CONCLUSION: This work suggests that CDH1 gene methylation and H. pylori infection are frequent events in samples from Brazilian patients with chronic gastritis and reinforces the correlation between H. pylori infection and CDH1 inactivation in early steps of gastric tumorigenesis.

Investigation into the controversial association of Streptococcus gallolyticus with colorectal cancer and adenoma

Background

The seroprevalence of IgG antibodies of Streptococcus gallolyticus subspecies gallolyticus, CIP 105428, was evaluated to investigate the controversial association of S. gallolyticus with colorectal carcinoma and adenoma in attempt to investigate the nature of such association if any, by exploring the mRNA expression of NF-κB and IL-8. Moreover, the serological behavior of S. gallolyticus IgG antibodies was compared to that of an indicator bacterium of bowel, Bacteroides fragilis.

Methods

ELISA was used to measure IgG antibodies of S. gallolyticus and B. fragilis in sera of 50 colorectal cancer, 14 colorectal adenoma patients, 30 age- and sex- matched apparently healthy volunteers (HV) and 30 age- and sex- matched colonoscopically-proven tumor-free control subjects. NF-κB and IL-8 mRNA expression was evaluated in tumorous and non-tumorous tissue sections of carcinoma and adenoma patients in comparison with that of control subjects by using in situ hybridization assay.

Results

Colorectal cancer and adenoma patients were associated with higher levels of serum S. gallolyticus IgG antibodies in comparison with HV and control subjects (P < 0.05) while no similar association was found with serum IgG antibodies of B. fragilis (P > 0.05). ELISA cutoff value for the seropositivity of S. gallolyticus IgG was calculated from tumor-free control group. The expression of NF-κB mRNA was higher in tumorous than non-tumorous tissue sections of adenoma and carcinoma, higher in carcinoma/adenoma sections than in control subjects, higher in tumorous sections of carcinoma than in adenoma patients, and higher in S. gallolyticus IgG seropositive than in seronegative groups in both tumorous and non-tumorous sections (P < 0.05). IL-8 mRNA expression in tumorous sections of adenoma and carcinoma was higher than in non-tumorous sections, higher in carcinoma/adenoma than in control subjects, and higher in S. gallolyticus IgG seropositive than in seronegative groups in tumorous rather than non-tumorous sections (P < 0.05).

Conclusion

S. gallolyticus most likely plays an essential role in the oncogenic progression of normal colorectal mucosa to adenoma and to CRC. This promoting/propagating role of S. gallolyticus might take place by utilizing certain inflammatory, anti-apoptotic, and angiogenic factors of transformation including NF-κB and IL-8.

Inflammation, immunity, and vaccines for Helicobacter pylori

Helicobacter pylori infects almost half of the population worldwide and represents the major cause of gastroduodenal diseases, such as duodenal and gastric ulcer, gastric adenocarcinoma, autoimmune gastritis, and B-cell lymphoma of mucosa-associated lymphoid tissue. Helicobacter pylori induces the activation of a complex and fascinating cytokine and chemokine network in the gastric mucosa. Different bacterial and environmental factors, other concomitant infections, and host genetics may influence the balance between mucosal tolerance and inflammation in the course of H. pylori infection. An inverse association between H. pylori prevalence and the frequencies of asthma and allergies was demonstrated, and the neutrophil activating protein of H. pylori was shown to inhibit the allergic inflammation of bronchial asthma. During the last year, significant progress was made on the road to the first efficient vaccine for H. pylori that will represent a novel and very important bullet against both infection and gastric cancer.