Gastric Cancer Due to Chronic H. pylori Infection: What We Know and Where We Are Going

Accuracy of Fecal Polymerase Chain Reaction Testing in Clarithromycin-Resistant Helicobacter Pylori: A Systematic Review and Meta-Analysis

INTRODUCTION

The increasing prevalence of clarithromycin (CLA)-resistant Helicobacter pylori(H. pylori) strains poses a significant challenge in the management of H. pylori infections. This systematic review and meta-analysis investigates the diagnostic accuracy of polymerase chain reaction (PCR) in identifying CLA-resistant H. pylori strains in stool.

METHODS

A comprehensive literature search was conducted using PubMed, Embase, and Cochrane databases from database inception to April 30, 2023. Eligible studies evaluated the effectiveness of PCR stool tests in detecting CLA-resistant H. pylori strains in adults (>18-year-old). Studies of pediatric populations, alternative methods to PCR or stool samples, and reference tests other than gastric biopsy were excluded. The bivariate random-effects model was used to pool diagnostic accuracy from the included studies.

RESULTS

The analysis of 11 prospective diagnostic studies with a total of 866 patients showed a pooled sensitivity of 0.97 (95% CI: 0.9-0.99) and a pooled specificity of 0.98 (95% CI: 0.81-1.00). Subgroup analysis based on the used technique demonstrated consistent findings without notable variations. The diagnostic odds ratio was calculated at 1843.92 (95% CI: 134.28-25,321.3). The positive likelihood ratio was determined as 51.02 (95% CI: 4.61-564.5), while the negative likelihood ratio was found to be 0.03 (95% CI: 0.01-0.1).

DISCUSSION

PCR testing for clarithromycin-resistant H. pylori was highly sensitive and specific across studies with proven reliability in clinical practice, particularly in outpatient settings. Their implementation offers cost-effectiveness and the potential for tailored treatment strategies, holding promise for improved patient outcomes.

Pyridylpiperazine-based carbodithioates as urease inhibitors: synthesis and biological evaluation

The urease enzyme is recognized as a valuable therapeutic agent for treating the virulent Helicobacter pylori bacterium because of its pivotal role in aiding the colonization and growth of the bacterium within the gastric mucosa. In order to control the harmful consequences of bacterial infections, urease inhibition presents itself as a promising and effective approach. The current research aimed to synthesize pyridylpiperazine-based carbodithioate derivatives 5a-5n and 7a-7n that could serve as potential drug candidates for preventing bacterial infections through urease inhibition. The synthesized carbodithioate derivatives 5a-5n and 7a-7n were explored to assess their ability to inhibit the urease enzyme after their structural explication by gas chromatography-mass spectrometry (GC-MS). In the in vitro evaluation with thiourea as a standard drug, it was observed that all the synthesized compounds exhibited significant inhibitory activity compared to the reference drug. Among the compounds tested, 5j (bearing an o-tolyl moiety) emerged as the most effective inhibitor, displaying strong urease inhibition with an IC50 value of 5.16 ± 2.68 μM. This IC50 value is notably lower than that of thiourea (23 ± 0.03 μM), indicating the significantly most potent potential of inhibition. In molecular docking of 5j within the active site of urease, numerous noteworthy interactions were identified.

Roles of long non‑coding RNA SNHG16 in human digestive system cancer (Review)

The incidence of tumors in the human digestive system is relatively high, including esophageal cancer, liver cancer, pancreatic cancer, gastric cancer and colorectal cancer. These malignancies arise from a complex interplay of environmental and genetic factors. Among them, long non‑coding RNAs (lncRNAs), which cannot be translated into proteins, serve an important role in the development, progression, migration and prognosis of tumors. Small nucleolar RNA host gene 16 (SNHG16) is a typical lncRNA, and its relationship with digestive system tumors has been widely explored. The prevailing hypothesis suggests that the principal molecular mechanism of SNHG16 in digestive system tumors involves it functioning as a competitive endogenous RNA that interacts with other proteins, regulates various genes and influences a downstream target molecule. The present review summarizes recent research on the relationship between SNHG16 and numerous types of digestive system cancer, encompassing its biological functions, underlying mechanisms and potential clinical implications. Furthermore, it outlines the association between SNHG16 expression and pertinent risk factors, such as smoking, infection and diet. The present review indicated the promise of SNHG16 as a potential biomarker and therapeutic target in human digestive system cancer.

Interaction Between Hypoxia-Inducible Factor 1-alpha Gene Polymorphism and Helicobacter pylori Infection on Gastric Cancer in a Chinese Tibetan Population

To investigate the impact of four single nucleotide polymorphisms (SNPs) of the HIF1α gene and its interaction with Helicobacter pylori (H. pylori) infection on susceptibility to gastric cancer (GC).Logistic regression was used to test the relationship between four SNPs of HIF1α gene and the susceptibility of GC. A generalized multifactor dimensionality reduction (GMDR) model was used to assess the HIF1α gene-H. pylori infection interaction.Logistic regression analysis indicated that both the rs11549465-CT genotype and the T allele were associated with an increased risk of GC, adjusted OR (95% CI) were 1.63 (1.09-2.20) (CT vs. CC) and 1.70 (1.13-2.36) (T vs. C), respectively. We also found that both the rs11549467-A allele and rs11549467-GA genotype were associated with an increased risk of GC, and adjusted OR (95% CI) were 2.21 (1.61-2.86) (GA vs. GG), 2.13 (1.65-2.65) (A vs. G), respectively. However, no statistically significant impact of rs2057482 or rs1957757 on risk of GC was found. The GMDR model indicated a statistically significant two-dimensional model combination (including rs11549467 and H. pylori infection). The selected model had testing balanced accuracy of 0.60 and the best cross-validation consistencies of 10/10 (p = 0.0107). Compared with H. pylori infection negative participants with rs11549467-GG genotype, H. pylori positive participants with the rs11549467-GA genotype had the highest GC risk, the OR (95% CI) was 3.04 (1.98-4.12).The rs11549467-A allele and rs11549467-GA genotype was associated with increased GC risk. Additionally, the gene-environment interaction between HIF-1α-rs11549467 and H. pylori infection was also correlated with an increased risk of GC.

Oral administration of DNA alginate nanovaccine induced immune-protection against Helicobacter pylori in Balb/C mice

BACKGROUND

Helicobacter pylori (H. Pylori), is an established causative factor for the development of gastric cancer and the induction of persistent stomach infections that may lead to peptic ulcers. In recent decades, several endeavours have been undertaken to develop a vaccine for H. pylori, although none have advanced to the clinical phase. The development of a successful H. pylori vaccine is hindered by particular challenges, such as the absence of secure mucosal vaccines to enhance local immune responses, the absence of identified antigens that are effective in vaccinations, and the absence of recognized indicators of protection.

METHODS

The DNA vaccine was chemically cloned, and the cloning was verified using PCR and restriction enzyme digestion. The efficacy of the vaccination was investigated. The immunogenicity and immune-protective efficacy of the vaccination were assessed in BALB/c mice. This study demonstrated that administering a preventive Alginate/pCI-neo-UreH Nanovaccine directly into the stomach effectively triggered a robust immune response to protect against H. pylori infection in mice.

RESULTS

The level of immune protection achieved with this nano vaccine was similar to that observed when using the widely accepted formalin-killed H. pylori Hel 305 as a positive control. The Alginate/pCI-neo-UreH Nanovaccine composition elicited significant mucosal and systemic antigen-specific antibody responses and strong intestinal and systemic Th1 responses. Moreover, the activation of IL-17R signaling is necessary for the defensive Th1 immune responses in the intestines triggered by Alginate/pCI-neo-UreH.

CONCLUSION

Alginate/pCI-neo-UreH is a potential Nanovaccine for use in an oral vaccine versus H. pylori infection, according to our findings.

Potential Gastric Cancer Immunotherapy: Stimulating the Immune System with Helicobacter pylori pIRES2-DsRed-Express-ureF DNA Vaccines

Most gastric cancers (GC) are thought to be caused by Helicobacter pylori (H. pylori) infections. However, there is mounting evidence that GC patients with positive H. pylori status have improved prognoses. The H. pylori-induced cellular immune reaction may inhibit cancer. In this study, BALB/c mice were immunized using recombinant plasmids that encode the ureF gene of H. pylori. Purified functional splenic CD3+ T lymphocytes are used to study the anticancer effects in vitro and in vivo. The immunological state of GC patients with ongoing H. pylori infection is mimicked by the H. pylori DNA vaccines, which cause a change in the reaction from Th1 to Th2. Human GC cells grow more slowly when stimulated CD3+ T lymphocytes are used as adoptive infusions because they reduce GC xenograft development in vivo. The more excellent ratios of infiltrating CD8+/CD4+ T cells, the decreased invasion of regulatory FOXP3+ Treg lymphocytes, and the increased apoptosis brought on by Caspase9/Caspase-3 overexpression and Survivin downregulation may all contribute to the consequences. Our findings suggest that in people with advanced GC, H. pylori pIRES2-DsRed-Express-ureF DNA vaccines may have immunotherapeutic utility.

The role of microbiota in esophageal squamous cell carcinoma: A review of the literature

Esophageal squamous cell carcinoma (ESCC) exhibits high incidence with poor prognosis. Alcohol drinking, cigarette smoking, and betel nut chewing are well-known risk factors. Dysbiosis, an imbalance of the microbiota residing in a local environment, is known to be associated with human diseases, especially cancer. This article reviews the current evidence of esophageal microbiota in ESCC carcinogenesis, including initiation, progression, and drug resistance. Articles involving the esophageal microbiota, diagnosis, treatment, and the progression of esophageal cancer were acquired using a comprehensive literature search in PubMed in recent 10 years. Based on 16S rRNA sequencing of human samples, cell, and animal studies, current evidence suggests dysbiosis of the esophagus promotes ESCC progression and chemotherapy resistance, leading to a poor prognosis. Smoking and drinking are associated with esophageal dysbiosis. Specific bacteria have been reported to promote carcinogenesis, involving either progression or drug resistance in ESCC, for example Porphyromonas gingivalis and Fusobacterium nucleatum. These bacteria promote ESCC cell proliferation and migration via the TLR4/NF-κB and IL-6/STAT3 pathways. F. nucleatum induces cisplatin resistance via the enrichment of immunosuppressive myeloid-derived suppressor cells (MDSCs). Correcting the dysbiosis and reducing the abundance of specific esophageal pathogens may help in suppressing cancer progression. In conclusion, esophageal dysbiosis is associated with ESCC progression and chemoresistance. Screening the oral and esophageal microbiota is a potential diagnostic tool for predicting ESCC development or drug-resistance. Repairing esophageal dysbiosis is a novel treatment for ESCC. Clinical trials with probiotics in addition to current chemotherapy are warranted to study the therapeutic effects.

The Lung Microbiome in COPD and Lung Cancer: Exploring the Potential of Metal-Based Drugs

Chronic obstructive pulmonary disease (COPD) and lung cancer 17 are two of the most prevalent and debilitating respiratory diseases worldwide, both associated with high morbidity and mortality rates. As major global health concerns, they impose a substantial burden on patients, healthcare systems, and society at large. Despite their distinct aetiologies, lung cancer and COPD share common risk factors, clinical features, and pathological pathways, which have spurred increasing research interest in their co-occurrence. One area of particular interest is the role of the lung microbiome in the development and progression of these diseases, including the transition from COPD to lung cancer. Exploring novel therapeutic strategies, such as metal-based drugs, offers a potential avenue for targeting the microbiome in these diseases to improve patient outcomes. This review aims to provide an overview of the current understanding of the lung microbiome, with a particular emphasis on COPD and lung cancer, and to discuss the potential of metal-based drugs as a therapeutic strategy for these conditions, specifically concerning targeting the microbiome.

Artesunate Dry Emulsion Formulation Combined with Antibiotics for Treatment of Helicobacter pylori Infections: In Vitro/In Vivo Evaluation

Helicobacter pylori is the primary pathogen responsible for causing gastroduodenal ulcers and stomach cancer. The standard treatment for H. pylori typically involves a combination of antibiotics and acid-reducing medications. However, the recurrence of ulcers is closely linked to the emergence of antibiotic resistance in H. pylori, necessitating the development of alternative drugs. This report focuses on the investigation of artesunate as a potential alternative to reduce antibiotic use and enhance effectiveness against H. pylori. Unfortunately, commercial artesunate is available in an acid form, which has poor solubility, especially in gastric acid fluid. The aim of this study is to utilize a water-soluble formulation of artesunate called dry emulsion formulation (ADEF) and combine it with amoxicillin to eradicate H. pylori. In vitro studies were conducted to evaluate the activity of ADEF against H. pylori and determine its inhibitory concentrations. In addition, pharmacokinetic parameters of orally administered ADEF and native artesunate were investigated in rats for in vivo studies. The results showed that when combined with amoxicillin and pantoprazole, ADEF exhibited effectiveness against H. pylori. It is worth noting that the solubility of ADEF in gastric acid appears to be a critical factor for achieving successful treatment. Consequently, ADEF could be considered a promising candidate for H. pylori therapy.

Expression Assessment of the Helicobacter pyloribabA and sabA Genes in Patients with Peptic Ulcer, Duodenal Ulcer and Gastric Cancer

Helicobacter pylori as a common gastrointestinal (GI) pathogen must possess certain virulence characteristics to colonize the stomach, evade host immune responses, and subsequently induce GI diseases. This research aimed to investigate the expression level of two important genes, the sialic acid-binding adherence (SabA) and the blood group antigen-binding adhesion (BabA) in H. pylori strains isolated from adult patients living in the northern part of Iran, and their association with peptic ulcer disease (PUD) and gastric cancer (GC). This cross-sectional study was carried out on adult patients referring to the GI clinic of the hospitals affiliated to Babol University of Medical Sciences, Iran. New cases diagnosed with gastritis, peptic ulcer or gastric cancer were included. Endoscopic-guided gastric biopsies were examined and H. pylori positive colonies were analyzed to determine the expression of babA and sabA genes, utilizing specific primers and the SYBR Green dye. Among 175 patients with mean age of 51.6±15.6 years, 101 (57.7%) of the individuals tested positive for H. pylori infection. Statistical analysis revealed a significant correlation between sabA (P=0.003) and babA (P=0.002) gene expression and development of PUD and GC. Smoking (P=0.052), gender (P=0.004) and positive babA gene expression (P=0.009) had the greatest association with occurrence of PUD or GC in H. pylori positive patients.  In summary, the presence of the sabA gene in people infected with H. pylori increased the risk of GC compared to gastritis, while, the presence of the babA gene was significantly increased in gastric ulcer patients. Considering the diversity of H. pylori isolates and the varying results observed in different geographical regions, further comprehensive studies are required to evaluate the function of these genes in H. pylori pathogenesis and their relationship with clinical outcomes.