Helicobacter Pylori and Gastric Cancer Progression

A review of potential mechanisms and treatments of gastric intestinal metaplasia

Gastric intestinal metaplasia (GIM) is a pathological process where gastric mucosal epithelial cells are replaced by intestinal-type cells, serving as a precursor lesion for gastric cancer. This transformation involves various genetic and environmental factors, affecting key genes and signaling pathways. Recent research has revealed complex mechanisms, including changes in gene expression, abnormal signaling pathway activation, and altered cell behavior. This review summarizes the latest research on GIM, discussing its pathogenesis, current treatment strategies, and potential efficacy of emerging approaches like gene editing, microbiome interventions, and integrative medicine. By exploring these strategies, we aim to provide more effective treatments for GIM and reduce gastric cancer incidence. The review also highlights the importance of interdisciplinary studies in understanding GIM mechanisms and improving treatment strategies.

Comprehensive multiomics analysis of the signatures of gastric mucosal bacteria and plasma metabolites across different stomach microhabitats in the development of gastric cancer

PURPOSE

As an important component of the microenvironment, the gastric microbiota and its metabolites are associated with tumour occurrence, progression, and metastasis. However, the relationship between the gastric microbiota and the development of gastric cancer is unclear. The present study investigated the role of the gastric mucosa microbiome and metabolites as aetiological factors in gastric carcinogenesis.

METHODS

Gastric biopsies from different stomach microhabitats (n = 70) were subjected to 16S rRNA gene sequencing, and blood samples (n = 95) were subjected to untargeted metabolome (gas chromatography‒mass spectrometry, GC‒MS) analyses. The datasets were analysed using various bioinformatics approaches.

RESULTS

The microbiota diversity and community composition markedly changed during gastric carcinogenesis. High Helicobacter. pylori colonization modified the overall diversity and composition of the microbiota associated with gastritis and cancer in the stomach. Most importantly, analysis of the functional features of the microbiota revealed that nitrate reductase genes were significantly enriched in the tumoral microbiota, while urease-producing genes were significantly enriched in the microbiota of H. pylori-positive patients. A panel of 81 metabolites was constructed to discriminate gastric cancer patients from gastritis patients, and a panel of 15 metabolites was constructed to discriminate H. pylori-positive patients from H. pylori-negative patients. receiver operator characteristic (ROC) curve analysis identified a series of gastric microbes and plasma metabolites as potential biomarkers of gastric cancer.

CONCLUSION

The present study identified a series of signatures that may play important roles in gastric carcinogenesis and have the potential to be used as biomarkers for diagnosis and for the surveillance of gastric cancer patients with minimal invasiveness.

MOMAST® Downregulates AQP3 Expression and Function in Human Colon Cells

The water channel AQP3 is an aquaglyceroporin expressed in villus epithelial cells, and it plays a role in water transport across human colonic surface cells. Beyond water, AQP3 can mediate glycerol and H2O2 transport. Abnormal expression and function of AQP3 have been found in various diseases often characterized by altered cell growth and proliferation. Here, the beneficial effects of MOMAST® have been evaluated. MOMAST® is an antioxidant-patented natural phenolic complex obtained from olive wastewater (OWW) of the Coratina cultivar. Treatment of human colon HCT8 cells with MOMAST® reduced cell viability. Confocal studies and Western Blotting analysis demonstrated that treatment with MOMAST® significantly decreased the staining and the expression of AQP3. Importantly, functional studies revealed that the reduction of AQP3 abundance correlates with a significant decrease in glycerol and H2O2 uptake. Indeed, the H2O2 transport was partially but significantly reduced in the presence of MOMAST® or DFP00173, a selective inhibitor of AQP3. In addition, the MOMAST®-induced AQP3 decrease was associated with reduced epithelial-mesenchymal transition (EMT)-related proteins such as vimentin and β-catenin. Together, these findings propose MOMAST® as a potential adjuvant in colon diseases associated with abnormal cell growth by targeting AQP3.

Efficacy of Lactobacillus spp. Supplementation in Helicobacter pylori Eradication: A Systematic Meta-Analysis of Randomized Controlled Trials With Trial Sequential Analysis

BACKGROUND

Helicobacter pylori infection is a major global health concern and has been associated with a number of gastrointestinal disorders. Probiotics, especially Lactobacillus spp., have been suggested to have beneficial effect in managing H. pylori infection. This meta-analysis of randomized control trials (RCTs) aimed to evaluate the effect of Lactobacillus spp. supplementation on H. pylori eradication rates and associated side effects when combined with standard therapy.

MATERIALS AND METHODS

Relevant studies were retrieved from PubMed, Scopus, Google Scholar and the Cochrane Library. Comprehensive Meta-Analysis (CMA) Software 4.0 was used for all the statistical analyses. TSA 0.9.5.10 Beta software was used for the trial sequential analysis (TSA). GRADEpro GDT was used to assess the certainty of evidence.

RESULTS

An analysis of 26 selected studies showed that supplementing with Lactobacillus spp. significantly increased the rates of H. pylori eradication in per-protocol (PP) analysis (Overall risk ratio [RR] = 1.063, p = 0.000, 95% CI of -0.21 to 2.11; adults: RR = 1.050, p = 0.005, 95% CI = -0.55 to 2.03, children: RR = 1.223, p = 0.001, 95% CI = -13.35 to 4.55). In comparison to quadruple therapy, Lactobacillus spp. supplementation to triple therapy showed significant benefit (RR: 1.124; p = 0.000, 95% CI of -0.48 to 2.61). L. reuteri supplementation indicated better efficacy (RR: 1.049; p = 0.055, 95% CI of -0.56 to 3.26) than Lactobacillus GG (RR: 0.980; p = 0.595, 95% CI of -0.69 to 1.21). The 28-30 day (RR: 1.103; p = 0.003, 95% CI of -2.14 to 4.19) and 14-day supplementation periods (RR: 1.102; p = 0.003, 95% CI of -1.69 to 3.51) showed the most improvement. The analysis also revealed that Lactobacillus spp. significantly reduced gastrointestinal side effects: nausea/vomiting (RR: 0.566; p = 0.037, -3.11 to 1.45), diarrhea (RR: 0.324; p = 0.000, -5.46 to 0.48), and abdominal pain (RR: 0.438; p = 0.007, -5.65 to 4.22). The effect on bloating was non-significant (RR: 0.820; p = 0.498, -4.01 to 0.96). TSA graphs validated sufficient evidence for the conclusions.

CONCLUSION

Lactobacillus spp. significantly enhances H. pylori eradication rates and may reduce gastrointestinal side effects when used alongside standard therapy, offering a promising adjunctive treatment option. The evidence was supported by TSA and assessed using GRADEpro, indicating a high certainty of the findings.

Chitosan-modified molybdenum selenide mediated efficient killing of Helicobacter pylori and treatment of gastric cancer

Helicobacter pylori (H. pylori) is one of the major causes of gastrointestinal diseases, including gastric cancer. However, the acidic environment of the stomach and H. pylori resistance severely impair the antimicrobial efficacy of oral drugs. Here, a biocompatible chitosan-modified molybdenum selenide (MoSe2@CS) was designed for the simultaneous photothermal treatment of H. pylori infection and gastric cancer. MoSe2@CS showed a photothermal conversion efficiency was as high as 45.7 %. In the H. pylori-infected mice model, MoSe2@CS displayed a high bacteriostasis ratio of 99.9 % upon near-infrared irradiation. The antimicrobial functionality was also proved by transcriptomic sequencing study, which showed that MoSe2@CS combined with NIR laser irradiation modulated the gene expression of a variety of H. pylori bioprocesses, including cell proliferation and inflammation-related pathways. Further gut flora analysis results indicated that MoSe2@CS mediated PTT of H. pylori did not affect the homeostasis of gut flora, which highlights its advantages over traditional antibiotic therapy. In addition, MoSe2@CS exhibited a good photothermal ablation effect and significantly inhibited gastric tumor growth in vitro and in vivo. The comprehensive application of MoSe2@CS in the PTT of H. pylori infection and gastric cancer provides a new avenue for the clinical treatment of H. pylori infection and related diseases.

GDF6 in gastric cancer upregulated by helicobacter pylori induces epithelial-mesenchymal translation via the TGF-β/SMAD3 signaling pathway

OBJECTIVE

To investigate the association between Helicobacter pylori infection and GDF6 expression in gastric cancer patients, and to determine its influence on prognosis and resistance to capecitabine.

METHODS

Tumor and adjacent non-tumor tissues were collected from 148 gastric cancer patients who underwent surgery in our department from October 2019 to June 2022. Of these patients, 78 tested positive for Helicobacter pylori and 70 tested negative. Hematoxylin-eosin (HE) and immunofluorescence staining were utilized to quantify GDF6 expression in cancerous and adjacent tissues. Patient prognosis was monitored via follow-up. Western blotting analyzed GDF6 expression in common gastric cancer cell lines. HGC27 cells exhibiting high GDF6 expression and BGC823 cells with low expression were used to create GDF6-silenced and overexpressed cell lines. The impact of GDF6 on the proliferation, migration, invasion, and cloning abilities of gastric cancer cells was evaluated using the CCK-8 assay, scratch test, Transwell assay, and plate colony formation assay. Fluorescent quantitative PCR and Western blotting assessed the effects of GDF6 levels on epithelial-mesenchymal transition (EMT) and tumor cell stemness.

RESULTS

GDF6 expression in gastric cancer tissues was significantly correlated with cancer grading and staging (P<0.05). Helicobacter pylori-positive tissues exhibited significantly higher GDF6 expression levels than negative samples (P<0.05). Kaplan-Meier survival analysis indicated that high GDF6 expression was associated with poor survival prognosis. Overexpressed GDF6 enhanced the proliferation, migration, and invasion abilities of gastric cancer cells, while silencing GDF6 yielded opposite results. Increased GDF6 expression upregulated TGF-β expression and the phosphorylation levels of SMAD3, leading to an elevation in mesenchymal cell markers N-cadherin, vimentin, and a reduction in epithelial cell markers cytokeratins, E-cadherin. Moreover, high GDF6 levels contributed to increased resistance to capecitabine and enhanced the expression of tumor stem cell markers Nanog, Sox-2, Oct-4, CD44, amplifying tumor cell stemness.

CONCLUSION

Helicobacter pylori infection is associated with increased GDF6 expression in gastric cancer tissue, correlating with poor survival prognosis. Elevated GDF6 expression promotes the proliferation, migration, and invasion abilities of gastric cancer cells, facilitates EMT via the TGF-β/SMAD3 pathway, and intensifies cell stemness and capecitabine resistance. Consequently, GDF6 presents itself as a potential new target for gastric cancer treatment.

DATA AVAILABILITY STATEMENT

The data that support the findings of this study are available from the corresponding author upon reasonable request.

TREM1 facilitates the development of gastric cancer through regulating neutrophil extracellular traps-mediated macrophage polarization

Triggering receptor expressed on myeloid cell 1 (TREM1) elevation is associated with the unfavorable prognosis of gastric cancer (GC) patients. This work uncovered the effects and mechanism of TREM1 in GC. IHC staining examined TREM1 expression in GC tissues. TREM1-knockout and TREM1 knock-in mice were generated prior to the construction of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced GC mice model. H&E staining detected the pathological alternations of gastric tissues. IHC staining tested Ki67 expression. Wright-Giemsa staining performed neutrophil counting and flow cytometry analysis measured neutrophil infiltration. ELISA analyzed serum and tissue myeloperoxidase (MPO) levels and serum MPO-DNA levels. Immunofluorescence, Western blotting and related kits detected NETs formation. Immunofluorescence and IHC staining evaluated macrophage polarization. In MNNG-treated GES-1 cells and phorbal myristate acetate (PMA)-treated neutrophils, TREM1 expression was also examined. CCK-8 method and Western blotting assayed cell proliferation. Western blotting and immunofluorescence detected NETs formation. Flow cytometry analysis detected the changes of macrophage typing. TREM1 was overexpressed in tumor tissues, MNNG-treated GES-1 cells and PMA-treated neutrophils. TREM1 deficiency hindered tumor growth, reduced neutrophil infiltration, NETs formation and stimulated M1 macrophage polarization in MNNG-induced GC models. Neutrophil extracellular traps (NETs) degrader DNase-1 countervailed the impacts of TREM1 on MNNG-induced GC models in vivo. Collectively, TREM1 knockdown obstructed NETs-mediated M2 macrophage polarization to hamper GC progression.

Dysregulation of autophagy in gastric carcinoma: Pathways to tumor progression and resistance to therapy

The considerable death rates and lack of symptoms in early stages of gastric cancer (GC) make it a major health problem worldwide. One of the most prominent risk factors is infection with Helicobacter pylori. Many biological processes, including those linked with cell death, are disrupted in GC. The cellular "self-digestion" mechanism necessary for regular balance maintenance, autophagy, is at the center of this disturbance. Misregulation of autophagy, however, plays a role in the development of GC. In this review, we will examine how autophagy interacts with other cell death processes, such as apoptosis and ferroptosis, and how it affects the progression of GC. In addition to wonderful its role in the epithelial-mesenchymal transition, it is engaged in GC metastasis. The role of autophagy in GC in promoting drug resistance stands out. There is growing interest in modulating autophagy for GC treatment, with research focusing on natural compounds, small-molecule inhibitors, and nanoparticles. These approaches could lead to breakthroughs in GC therapy, offering new hope in the fight against this challenging disease.

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.

Vonoprazan-based therapies versus PPI-based therapies in patients with H. pylori infection: Systematic review and meta-analyses of randomized controlled trials

BACKGROUND

This study aims to evaluate the efficacy and safety of vonoprazan-amoxicillin (VA), vonoprazan-amoxicillin-clarithromycin (VAC), vonoprazan-based bismuth-containing quadruple therapy (VBQT), and PPI-based triple (PAC) or quadruple therapy (PBQT) for H. pylori infection with the consideration of duration of therapy and amoxicillin dose (H: high; L: low).

MATERIALS AND METHODS

PubMed, Embase, and the Cochrane Central Register of Controlled Trials were searched for eligible randomized controlled trials (RCTs) up to December 15, 2023. The efficacy outcome was eradication rate, and safety outcomes included the rates of adverse events and treatment discontinuation.

RESULTS

Twenty-seven RCTs were included. The pooled eradication rates were 82.8% for VA, 89.1% for VAC, and 91.8% for VBQT, which increased with the higher amoxicillin frequency of administration and extended duration of therapy within each regimen. There were no significant differences in eradication rate when comparing 7-VA versus 7-VAC and 14-VA versus 14-VAC. VA was at least comparable to PAC. The eradication rate did not differ significantly between 10-H-VA or 14-H-VA versus 14-PBQT. 7-L-VAC demonstrated higher eradication rate versus 7-PAC and comparable rate to 14-PAC. 14-VBQT showed higher eradication rates versus 14-PBQT. The adverse events rate was 19.3% for VA, 30.6% for VAC, and 38.4% for VBQT. VA had similar risk of adverse events versus VAC and significantly fewer adverse events compared to PBQT. The treatment discontinuation rate did not differ significantly between treatments.

CONCLUSIONS

The eradication rate of VBQT was the highest at above 90% followed by VAC and VA. VA was as effective as VAC and superior to PPI-based therapies with favorable safety, highlighting the potential of VA therapy as a promising alternative to traditional PPI-based therapies. VPZ-based triple or quadruple therapies was more effective than PPI-based therapies. Further studies are needed to establish the optimal treatment regimen especially in the western countries.

Prognostic Value and Therapeutic Significance of CCL Chemokines in Gastric Cancer

BACKGROUND

Gastric cancer is one of the most common malignant tumours of the gastrointestinal tract, which has a significant negative impact on human health.

AIMS

CCL chemokines play important roles in a variety of tumor microenvironments; nevertheless, gastric cancer has surprisingly limited associations with CCL chemokines.

METHODS

In our study, we comprehensively utilized bioinformatics analysis tools and databases such as cBioPortal, UALCAN, GEPIA, GeneMANIA, STRING, and TRRUST to clarify the clinical significance and biology function of CCL chemokines in gastric cancer.

RESULTS

The mRNA expression levels of CCL1/3/4/5/7/8/14/15/18/20/21/22/26 were up-regulated, while the mRNA expression levels of CCL2/11/13/16/17/19/23/24/25/28 were down-regulated. The chemokine significantly associated with the pathological stage of gastric cancer is CCL2/11/19/21. In gastric cancer, the expression level of CCL chemokines was not associated with disease-free survival, but low expression of CCL14 was significantly associated with longer overall survival. Therein, associated with the regulation of CCL chemokines are only 10 transcription factors (RELA, NFKB1, STAT6, IRF3, REL, SPI1, STAT1, STAT3, JUN and SP1). The major biological process and functional enrichment of CCL chemokines are to induce cell-directed migration.

CONCLUSION

These results may indicate that CCL chemokines may be immunotherapeutic targets and promising prognostic biomarkers for gastric cancer.

Helicobacter pylori-associated Chronic Atrophic Gastritis and Progression of Gastric Carcinogenesis

Chronic inflammation due to a Helicobacter pylori (H. pylori) infection is a representative cause of gastric cancer that can promote gastric carcinogenesis by abnormally activating immune cells and increasing the inflammatory cytokines levels. H. pylori infections directly cause DNA double-strand breaks in gastric epithelial cells and genetic damage by increasing the enzymatic activity of cytidine deaminase. Eventually, gastric cancer is induced through dysplasia. Hypermethylation of tumor suppressor genes is an important cause of gastric cancer because of a H. pylori infection. In addition, the changes in gastric microbiota and the mucosal inflammatory changes associated with a co-infection with the Epstein-Barr virus are associated with gastric cancer development. DNA damage induced by H. pylori and the subsequent responses of gastric stem cells have implications for gastric carcinogenesis. Although the pathogenesis of H. pylori has been established, many uncertainties remain, requiring more study.

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.

Association of PTGER4 and PRKAA1 genetic polymorphisms with gastric cancer

BACKGROUND

Gastric cancer (GC) is one of the most common malignancies, affected by several genetic loci in the clinical phenotype. This study aimed to determine the association between PTGER4 and PRKAA1 gene polymorphisms and the risk of GC.

METHODS

A total of 509 GC patients and 507 age and sex-matched healthy controls were recruited to explore the association between PTGER4 and PRKAA1 genetic polymorphisms and GC susceptibility. Logistic regression analysis was used to study the correlation between these SNPs and GC, with odd ratio (OR) and 95% confidence interval (CI) as indicators. Multifactor dimensionality reduction was utilized to analyze the genetic relationships among SNPs. was conducted to predict gene expression, the impact of SNPs on gene expression, and the signaling pathways involved in PTGER4 and PRKAA1.

RESULTS

Overall, rs10036575 in PTGER4 (OR = 0.82, p = 0.029), rs10074991 (OR = 0.82, p = 0.024) and rs13361707 (OR = 0.82, p = 0.030) in PRKAA1 were associated with susceptibility to GC. Stratification analysis revealed that the effects of these SNPs in PTGER4 and PRKAA1 on GC susceptibility were dependent on smoking and were associated with a reduced risk of adenocarcinoma (p < 0.05). Bioinformatics analysis showed an association between SNPs and corresponding gene expression (p < 0.05), and PRKAA1 may affect GC by mediating RhoA.

CONCLUSION

This study suggests that PTGER4 and PRKAA1 SNPs might affect the susceptibility of GC, providing a new biological perspective for GC risk assessment, pathogenesis exploration, and personalized treatment.

Coding RNA expression profile and transcription factor analysis of H.pylori-associated chronic atrophic gastritis

PURPOSE

Atrophic gastritis, one of the processes leading to gastric cancer (GC), is closely related to Helicobacter pylori (HP) infection. This study aimed to understand how HP causes chronic inflammation that leads to ulcers and stomach problems.

METHODS

Twenty-eight CAG patients were included in the study (9 HP-infected and 19 HP-uninfected). Endoscopy, histopathology, and high-throughput mRNA sequencing were performed. Differentially expressed genes (DEGs) were validated via qRT-PCR.

RESULTS

Principal component analysis (PCA) results showed that more than 88.9 ​% of the samples were classified into the HP (+) group. A total of 157 DEGs were identified, of which 38 were up-regulated and 119 were down-regulated. The DEGs were mainly enriched in the biological process (BP) terms associated with immune system process, adaptive immune response, G protein-coupled receptor signaling pathway, as well as point to numerous key pathways, including fat digestion and absorption, retinol metabolism, steroid hormone biosynthesis, ascorbate and aldarate metabolism, and chemical carcinogenesis. APOA1, APOA4, FOXP3, NR1H4, ABCG5, ACTA1, CCL19, CCR7, CYP3A4, and PDCD had the highest degrees in protein-protein interaction network as the hub genes; they were also included into the transcription factor (TF)-target network except for PDCD. APOA1 and CYP3A4 were extremely significantly up-regulated in HP (+) CAG patients compared with the HP (-) CAG patients, while FOXP3, CCR7 and CCL19 were significantly down-regulated.

CONCLUSION

The expression of APOA1, CYP3A4, FOXP3, CCR7, and CCL19 are the potential indicators for CAG to GC development, being the biomarkers to predict progression of CAG and poor prognosis of GC.

Short-chain fatty acids in cancer pathogenesis

Cancer is a multi-step process that can be viewed as a cellular and immunological shift away from homeostasis in response to selected infectious agents, mutations, diet, and environmental carcinogens. Homeostasis, which contributes importantly to the definition of "health," is maintained, in part by the production of short-chain fatty acids (SCFAs), which are metabolites of specific gut bacteria. Alteration in the composition of gut bacteria, or dysbiosis, is often a major risk factor for some two dozen tumor types. Dysbiosis is often characterized by diminished levels of SCFAs in the stool, and the presence of a "leaky gut," permitting the penetration of microbes and microbial derived molecules (e.g., lipopolysaccharides) through the gut wall, thereby triggering chronic inflammation. SCFAs attenuate inflammation by inhibiting the activation of nuclear factor kappa B, by decreasing the expression of pro-inflammatory cytokines such as tumor necrosis factor alpha, by stimulating the expression of anti-inflammatory cytokines such as interleukin-10 and transforming growth factor beta, and by promoting the differentiation of naïve T cells into T regulatory cells, which down-regulate immune responses by immunomodulation. SCFA function epigenetically by inhibiting selected histone acetyltransferases that alter the expression of multiple genes and the activity of many signaling pathways (e.g., Wnt, Hedgehog, Hippo, and Notch) that contribute to the pathogenesis of cancer. SCFAs block cancer stem cell proliferation, thereby potentially delaying or inhibiting cancer development or relapse by targeting genes and pathways that are mutated in tumors (e.g., epidermal growth factor receptor, hepatocyte growth factor, and MET) and by promoting the expression of tumor suppressors (e.g., by up-regulating PTEN and p53). When administered properly, SCFAs have many advantages compared to probiotic bacteria and fecal transplants. In carcinogenesis, SCFAs are toxic against tumor cells but not to surrounding tissue due to differences in their metabolic fate. Multiple hallmarks of cancer are also targets of SCFAs. These data suggest that SCFAs may re-establish homeostasis without overt toxicity and either delay or prevent the development of various tumor types.

High-Salt Diet Exacerbates H. pylori Infection and Increases Gastric Cancer Risks

Gastric cancer ranks as the fifth-leading contributor to global cancer incidence and the fourth-highest in terms of cancer-related mortality. Helicobacter pylori (H. pylori) infection leads to inflammation and ulceration, atrophic and chronic gastritis, and eventually, increases the risk of developing gastric adenocarcinoma. In this paper, we delve into the combined impact of a high-salt diet (HSD) and concurrent H. pylori infection, which act as predisposing factors for gastric malignancy. A multitude of mechanisms come into play, fostering the development of gastric adenocarcinoma due to the synergy between an HSD and H. pylori colonization. These encompass the disruption of mucosal barriers, cellular integrity, modulation of H. pylori gene expression, oxidative stress induction, and provocation of inflammatory responses. On the whole, gastric cancer patients were reported to have a higher median sodium intake with respect to healthy controls. H. pylori infection constitutes an additional risk factor, with a particular impact on the population with the highest daily sodium intake. Consequently, drawing from epidemiological discoveries, substantial evidence suggests that diminishing salt intake and employing antibacterial therapeutics could potentially lower the susceptibility to gastric cancer among individuals.

An oxidative stress biomarkers predict prognosis in gastric cancer patients receiving immune checkpoint inhibitor

Objective

The development and advance of gastric cancer are inextricably linked to oxidative and antioxidant imbalance. Although immunotherapy has been shown to be clinically effective, the link between oxidative stress and gastric cancer patients treated with immune checkpoint inhibitor (ICIs) remains unknown. This study aims at looking into the prognostic value of oxidative stress scores in gastric cancer patients treated with ICIs.

Methods

By taking the propagation to receiver operating characteristic (ROC) we got the best cut-off values, and divided 265 patients receiving ICIs and chemotherapy into high and low GC-Integrated Oxidative Stress Score (GIOSS) groups. We also used Kaplan-Meier and COX regression models to investigate the relationship between oxidative stress biomarkers and prognosis.

Results

Through both univariate and multivariate analyses, it's shown that GIOSS severs as an independent prognostic factor for progression-free survival (PFS) and Overall survival (OS). Based on GIOSS cutoff values, patients with high GIOSS levels, compared to those with low levels exhibited shorter PFS and OS, both in the high GIOSS group, which performed poorly in the ICIs subgroup and other subgroup analyses.

Conclusion

GIOSS is a biomarker that responds to systemic oxidative stress in the body and can predict prognosis in patients with gastric cancer who are taking ICIs. Additionally, it might come to medical professionals' aid in making more effective or more suitable treatment plans for gastric cancer.

A comparative study of laboratory methods for detecting Helicobacter pylori antibiotic resistance

The rise of antibiotic resistance in H. pylori has led to a decrease in the effectiveness of eradication therapy. Treatment plans are now chosen based on local antibiotic resistance data, with a primary focus on clarithromycin. An approach tailored to individual patients for H. pylori eradication has been proposed, involving the assessment of antibiotic resistance before starting the initial treatment. The objective of this study is to compare and describe phenotypic and molecular-genetic methods for detecting antibiotic resistance in H. pylori, while also evaluating their diagnostic accuracy. Materials and methods. In this study, we examined 25 cultures of H. pylori with known phenotypic sensitivity and resistance to antibacterial agents. We determined resistance to clarithromycin and levofloxacin through a series of dilutions in Mueller-Hinton agar with added sheep blood, following the guidelines of the Clinical and Laboratory Standards Institute (CLSI). Molecular markers of resistance were analyzed using Sanger sequencing and real-time polymerase chain reaction (RT-PCR) with specific primers. To assess the diagnostic accuracy, we compared the results of these molecular methods with those of the phenotypic method. Results. We established a complete agreement between the results obtained through phenotypic and molecular methods when detecting H. pylori resistance to clarithromycin. When evaluating levofloxacin resistance, we observed that cultures displaying phenotypic resistance also harbored mutations in the gyrA gene associated with resistance. Interestingly, some cultures without phenotypic resistance still exhibited characteristic gyrA gene mutations. The molecular methods demonstrated 100% sensitivity in detecting clarithromycin resistance and 100% sensitivity in detecting levofloxacin resistance, with a specificity of 78.57%. Conclusion. This research highlights a strong correlation between phenotypic and molecular resistance assessments in H. pylori, particularly in the case of clarithromycin. Sanger sequencing and RT-PCR consistently yielded reliable results, underscoring the trustworthiness of these methods.

Innate Immune Program in Formation of Tumor-Initiating Cells from Cells-of-Origin of Breast, Prostate, and Ovarian Cancers

Tumor-initiating cells (TICs), also known as cancer stem cells (CSCs), are cancer cells that can initiate a tumor, possess self-renewal capacity, and can contribute to tumor heterogeneity. TICs/CSCs are developed from their cells-of-origin. In breast, prostate, and ovarian cancers, progenitor cells for mammary alveolar cells, prostate luminal (secretory) cells, and fallopian tube secretory cells are the preferred cellular origins for their corresponding cancer types. These luminal progenitors (LPs) express common innate immune program (e.g., Toll-like receptor (TLR) signaling)-related genes. Microbes such as bacteria are now found in breast, prostate, and fallopian tube tissues and their corresponding cancer types, raising the possibility that their LPs may sense the presence of microbes and trigger their innate immune/TLR pathways, leading to an inflammatory microenvironment. Crosstalk between immune cells (e.g., macrophages) and affected epithelial cells (e.g., LPs) may eventually contribute to formation of TICs/CSCs from their corresponding LPs, in part via STAT3 and/or NFκB pathways. As such, TICs/CSCs can inherit expression of innate-immunity/TLR-pathway-related genes from their cells-of-origin; the innate immune program may also represent their unique vulnerability, which can be explored therapeutically (e.g., by enhancing immunotherapy via augmenting TLR signaling).