Gastric MALT lymphoma and Helicobacter pylori

Primary hepatic mucosa-associated lymphoid tissue lymphoma: a case report and literature review

Objective

To investigate the pathogenesis, clinical manifestations, imaging and pathological features, and treatment methods of primary hepatic lymphoma (PHL).

Case presentation

A 61-year-old male with a history of hepatitis B virus (HBV) infection presented to the hospital complaining of abdominal pain. Preoperative abdominal computed tomography (CT) revealed a mass in the right lobe of the liver, accompanied by an elevated alpha-fetoprotein (AFP) level. Consequently, hepatocellular carcinoma (HCC) was initially suspected. Following a comprehensive multidisciplinary consultation, the patient underwent an anatomical hepatectomy. Histopathological examination post-surgery confirmed the diagnosis of primary hepatic mucosa-associated lymphoid tissue (MALT) lymphoma. The patient received chemotherapy as an adjunct to surgical treatment. During the five-year follow-up period, there was no evidence of tumor recurrence.

Conclusion

Primary hepatic MALT lymphoma is infrequently encountered in clinical practice. Its clinical and radiological presentations are often nonspecific, making the pathological evaluation the definitive diagnostic tool. Surgical resection, in conjunction with chemotherapy, remains the cornerstone of management for this condition. The prognosis for most patients is favorable.

Machine Learning-Driven Classification of Urease Inhibitors Leveraging Physicochemical Properties as Effective Filter Criteria

Urease, a pivotal enzyme in nitrogen metabolism, plays a crucial role in various microorganisms, including the pathogenic Helicobacter pylori. Inhibiting urease activity offers a promising approach to combating infections and associated ailments, such as chronic kidney diseases and gastric cancer. However, identifying potent urease inhibitors remains challenging due to resistance issues that hinder traditional approaches. Recently, machine learning (ML)-based models have demonstrated the ability to predict the bioactivity of molecules rapidly and effectively. In this study, we present ML models designed to predict urease inhibitors by leveraging essential physicochemical properties. The methodological approach involved constructing a dataset of urease inhibitors through an extensive literature search. Subsequently, these inhibitors were characterized based on physicochemical properties calculations. An exploratory data analysis was then conducted to identify and analyze critical features. Ultimately, 252 classification models were trained, utilizing a combination of seven ML algorithms, three attribute selection methods, and six different strategies for categorizing inhibitory activity. The investigation unveiled discernible trends distinguishing urease inhibitors from non-inhibitors. This differentiation enabled the identification of essential features that are crucial for precise classification. Through a comprehensive comparison of ML algorithms, tree-based methods like random forest, decision tree, and XGBoost exhibited superior performance. Additionally, incorporating the "chemical family type" attribute significantly enhanced model accuracy. Strategies involving a gray-zone categorization demonstrated marked improvements in predictive precision. This research underscores the transformative potential of ML in predicting urease inhibitors. The meticulous methodology outlined herein offers actionable insights for developing robust predictive models within biochemical systems.

Feasibility of oral doxycycline as first-line therapy for conjunctival mucosa-associated lymphoid tissue lymphoma

OBJECTIVES

To investigate the long-term outcomes of oral doxycycline as first-line treatment in patients with conjunctival extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma).

METHODS

In this case series, the medical records of 67 patients with conjunctival MALT lymphoma who received doxycycline as their primary treatment and were followed up for at least 5 years were retrospectively reviewed. Progression-free survival (PFS) was analysed at 3, 5, and 10 years after the initial doxycycline treatment. A Cox proportional hazards model was used to assess the independent risk factors for progression.

RESULTS

After the initial treatment, 25 patients (37.3%) achieved a complete response, 8 patients (11.9%) achieved a partial response, 30 patients (44.8%) showed stable disease, and 4 patients (6.0%) showed disease progression. The median PFS in all patients was 168 months, and the 3-, 5- and 10-year PFS rates for all patients were 70%, 65%, and 62%, respectively. No further progression was observed 6 years after the initial doxycycline treatment. Younger age and TNM stage T1c were significant risk factors for the time to progression in the multivariate Cox regression analysis (p < 0.05). Additional doxycycline (>2 cycles) showed no benefit. There were no serious adverse events associated with doxycycline therapy, and most patients were successfully salvaged by second-line treatments, including radiotherapy and chemotherapy.

CONCLUSION

In this case series, oral doxycycline treatment yielded acceptable long-term PFS with minimal complications. Especially in patients with stage T1a or T1b conjunctival MALT lymphoma, first-line doxycycline treatment could be considered under close monitoring for at least 6 years.

Helicobacter pylori infection: a dynamic process from diagnosis to treatment

Helicobacter pylori, a gram-negative microaerophilic pathogen, causes several upper gastrointestinal diseases, such as chronic gastritis, peptic ulcer disease, and gastric cancer. For the diseases listed above, H. pylori has different pathogenic mechanisms, including colonization and virulence factor expression. It is essential to make accurate diagnoses and provide patients with effective treatment to achieve positive clinical outcomes. Detection of H. pylori can be accomplished invasively and noninvasively, with both having advantages and limitations. To enhance therapeutic outcomes, novel therapeutic regimens, as well as adjunctive therapies with probiotics and traditional Chinese medicine, have been attempted along with traditional empiric treatments, such as triple and bismuth quadruple therapies. An H. pylori infection, however, is difficult to eradicate during treatment owing to bacterial resistance, and there is no commonly available preventive vaccine. The purpose of this review is to provide an overview of our understanding of H. pylori infections and to highlight current treatment and diagnostic options.

An Overview of Selected Bacterial Infections in Cancer, Their Virulence Factors, and Some Aspects of Infection Management

In cancer development and its clinical course, bacteria can be involved in etiology and secondary infection. Regarding etiology, various epidemiological studies have revealed that Helicobacter pylori can directly impact gastric carcinogenesis. The Helicobacter pylori-associated virulence factor cytotoxin-associated gene A perhaps plays an important role through different mechanisms such as aberrant DNA methylation, activation of nuclear factor kappa B, and modulation of the Wnt/β-catenin signaling pathway. Many other bacteria, including Salmonella and Pseudomonas, can also affect Wnt/β-catenin signaling. Although Helicobacter pylori is involved in both gastric adenocarcinoma and mucosa-associated lymphoid tissue lymphoma, its role in the latter disease is more complicated. Among other bacterial species, Chlamydia is linked with a diverse range of diseases including cancers of different sites. The cellular organizations of Chlamydia are highly complex. Interestingly, Escherichia coli is believed to be associated with colon cancer development. Microorganisms such as Escherichia coli and Pseudomonas aeruginosa are frequently isolated from secondary infections in cancer patients. In these patients, the common sites of infection are the respiratory, gastrointestinal, and urinary tracts. There is an alarming rise in infections with multidrug-resistant bacteria and the scarcity of suitable antimicrobial agents adversely influences prognosis. Therefore, effective implementation of antimicrobial stewardship strategies is important in cancer patients.

Primary hepatic lymphoma of MALT type mimicking hepatic adenoma treated by hepatectomy: a case report and literature review

Background

Primary hepatic lymphoma (PHL) is a rare malignant tumor. Extranodal marginal zone lymphoma of the mucosa-associated lymphoid tissue (MALT) is an indolent lymphoma occurring at extranodal sites. The stomach is the most common organ affected by MALT lymphoma, whereas liver-related lymphoma is rarely reported. Its atypical clinical presentation often delays the diagnosis. Owing to the rarity of PHL, identifying its optimal treatment still remains a challenge. Herein, we report a case of PHL of the MALT type mimicking hepatic adenoma that was treated by hepatectomy without chemotherapy and review the scarce literature. Our findings suggest that surgery is an alternative approach to cure patients with localized hepatic lymphoma.

Case summary

A 55-year-old woman was admitted to our hospital because of upper abdominal discomfort, and a liver lesion was detected by computed tomography. She did not have nausea, fever, fatigue, jaundice, weakness, night sweats, or weight loss before admission. And her previous medical history was unremarkable. There were no positive signs on physical examination. Based on her preoperative examination including magnetic resonance imaging, the liver lesion was suspected to be a hepatic adenoma; however, the possibility of it being a malignancy like hepatocellular carcinoma was not excluded. Therefore, a decision of resection of the lesion was made. During the operation, hepatectomy of segment 4b and cholecystectomy were performed. The patient recovered well; however, after postoperative pathological examination, the lesion was diagnosed as a hepatic lymphoma of MALT type. The patient was reluctant to undergo chemotherapy or radiotherapy. At 18-month follow-up, no significant recurrence was observed, indicating that the treatment had a curative effect.

Conclusion

Notably, primary hepatic lymphoma of MALT type is a rare, low-grade B-cell malignancy. Making an accurate preoperative diagnosis of this disease is usually difficult, and liver biopsy is an appropriate avenue to improve the diagnostic accuracy. In patients with a localized tumor lesion, hepatectomy followed by chemotherapy or radiotherapy should be considered to achieve better outcomes. Although this study describes an unusual type of hepatic lymphoma mimicking a benign tumor, it has its inherent limitations. More clinical studies are required to establish guidelines for the diagnosis and treatment of this rare disease.

Helicobacter pylori infection

Helicobacter pylori infection causes chronic gastritis, which can progress to severe gastroduodenal pathologies, including peptic ulcer, gastric cancer and gastric mucosa-associated lymphoid tissue lymphoma. H. pylori is usually transmitted in childhood and persists for life if untreated. The infection affects around half of the population in the world but prevalence varies according to location and sanitation standards. H. pylori has unique properties to colonize gastric epithelium in an acidic environment. The pathophysiology of H. pylori infection is dependent on complex bacterial virulence mechanisms and their interaction with the host immune system and environmental factors, resulting in distinct gastritis phenotypes that determine possible progression to different gastroduodenal pathologies. The causative role of H. pylori infection in gastric cancer development presents the opportunity for preventive screen-and-treat strategies. Invasive, endoscopy-based and non-invasive methods, including breath, stool and serological tests, are used in the diagnosis of H. pylori infection. Their use depends on the specific individual patient history and local availability. H. pylori treatment consists of a strong acid suppressant in various combinations with antibiotics and/or bismuth. The dramatic increase in resistance to key antibiotics used in H. pylori eradication demands antibiotic susceptibility testing, surveillance of resistance and antibiotic stewardship.

Third-line and rescue therapy for refractory Helicobacter pylori infection: A systematic review

BACKGROUND

Due to increasing resistance rates of Helicobacter pylori (H. pylori) to different antibiotics, failures in eradication therapies are becoming more frequent. Even though eradication criteria and treatment algorithms for first-line and second-line therapy against H. pylori infection are well-established, there is no clear recommendation for third-line and rescue therapy in refractory H. pylori infection.

AIM

To perform a systematic review evaluating the efficacy and safety of rescue therapies against refractory H. pylori infection.

METHODS

A systematic search of available rescue treatments for refractory H. pylori infection was conducted on the National Library of Medicine’s PubMed search platform based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Randomized or non-randomized clinical trials and observational studies evaluating the effectiveness of H. pylori infection rescue therapies were included.

RESULTS

Twenty-eight studies were included in the analysis of mean eradication rates as rescue therapy, and 21 of these were selected for analysis of mean eradication rate as third-line treatment. For rifabutin-, sitafloxacin-, levofloxacin-, or metronidazole-based triple-therapy as third-line treatment, mean eradication rates of 81.6% and 84.4%, 79.4% and 81.5%, 55.7% and 60.6%, and 62.0% and 63.0% were found in intention-to-treat (ITT) and per-protocol (PP) analysis, respectively. For third-line quadruple therapy, mean eradication rates of 69.2% and 72.1% were found for bismuth quadruple therapy (BQT), 88.9% and 90.9% for bismuth quadruple therapy, three-in-one, Pylera^® (BQT-Pylera), and 61.3% and 64.2% for non-BQT) in ITT and PP analysis, respectively. For rifabutin-, sitafloxacin-, levofloxacin-, or metronidazole-based triple therapy as rescue therapy, mean eradication rates of 75.4% and 78.8%, 79.4 and 81.5%, 55.7% and 60.6%, and 62.0% and 63.0% were found in ITT and PP analysis, respectively. For quadruple therapy as rescue treatment, mean eradication rates of 76.7% and 79.2% for BQT, 84.9% and 87.8% for BQT-Pylera, and 61.3% and 64.2% for non-BQT were found in ITT and PP analysis, respectively. For susceptibility-guided therapy, mean eradication rates as third-line and rescue treatment were 75.0% in ITT and 79.2% in PP analysis.

CONCLUSION

We recommend sitafloxacin-based triple therapy containing vonoprazan in regions with low macrolide resistance profile. In regions with known resistance to macrolides or unavailability of bismuth, rifabutin-based triple therapy is recommended.

Transformed diffuse large B-cell lymphoma of the stomach in a patient with Sjögren's disease and systemic sclerosis: case report and literature review

This article describes a case of a transformed diffuse large B-cell lymphoma of the stomach in a patient with Sjögren's disease (SjD) and systemic sclerosis (SSc), as well as a brief review of the literature on lymphoproliferative diseases in SjD and SSc.

Identifying tumor antigens and immune subtypes of gastrointestinal MALT lymphoma for immunotherapy development

MALT lymphoma is an extranodal B-cell lymphoma of the marginal zone of mucosa-associated lymphoid tissue (MALT), caused by malignant transformation of B-cells in the marginal zone. In this work, we aim to explore the potential relationship between MALT lymphoma and DLBCL. Vaccines derived from messenger ribonucleic acid (mRNA) may provide satisfactory results. Despite being a promising treatment option, immunotherapy isn't widely used in treating renal cell carcinoma, as only a few patients respond to the treatment. The Cancer Genome Atlas (TCGA) analysis revealed gene expression profiles and clinical information. Antigen-presenting cells infiltrated the immune system using TIMER tool (http://timer.cistrome.org/). GDSC (Genomics of Drug Sensitivity in Cancer) data were used to estimate drug sensitivity. Immune-related genes were associated with a better prognosis in MALT lymphoma patients and higher levels of antigen-presenting cells. There is a significant relationship between these immune subtypes and immunological checkpoints, immunogenic cell death regulators, and prognostic variables for MALT lymphoma patients. In this study, we provide a theoretical foundation for the development of mRNA vaccines and suggest that KLHL14 could potentially be used as antigens to develop mRNA vaccines for MALT lymphoma.

Perspectives from recent advances of Helicobacter pylori vaccines research

BACKGROUND

Helicobacter pylori (H. pylori) infection is the main factor leading to some gastric diseases. Currently, H. pylori infection is primarily treated with antibiotics. However, with the widespread application of antibiotics, H. pylori resistance to antibiotics has also gradually increased year by year. Vaccines may be an alternative solution to clear H. pylori.

AIMS

By reviewing the recent progress on H. pylori vaccines, we expected it to lead to more research efforts to accelerate breakthroughs in this field.

MATERIALS & METHODS

We searched the research on H. pylori vaccine in recent years through PubMed®, and then classified and summarized these studies.

RESULTS

The study of the pathogenic mechanism of H. pylori has led to the development of vaccines using some antigens, such as urease, catalase, and heat shock protein (Hsp). Based on these antigens, whole-cell, subunit, nucleic acid, vector, and H. pylori exosome vaccines have been tested.

DISCUSSION

At present, researchers have developed many types of vaccines, such as whole cell vaccines, subunit vaccines, vector vaccines, etc. However, although some of these vaccines induced protective immunity in mouse models, only a few were able to move into human trials. We propose that mRNA vaccine may play an important role in preventing or treating H. pylori infection. The current study shows that we have developed various types of vaccines based on the virulence factors of H. pylori. However, only a few vaccines have entered human clinical trials. In order to improve the efficacy of vaccines, it is necessary to enhance T-cell immunity.

CONCLUSION

We should fully understand the pathogenic mechanism of H. pylori and find its core antigen as a vaccine target.

Histopathological Features of Helicobacter pylori Infection in Gastric Mucosa

Objective

To investigate the histopathological characteristics of Helicobacter pylori (Hp) infection in the gastric mucosa in the process from occurrence to intraepithelial neoplasia.

Methods

Specimens obtained from the endoscopic biopsy and endoscopic submucosal dissection of 2457 cases of gastric Hp infection were observed and assessed in detail using histology and immunohistochemistry techniques. The condition was divided according to the histopathological characteristics of gastric mucosal damage caused by Hp infection. The histopathological characteristics and immunophenotype of each stage were subsequently elucidated.

Results

Helicobacter pylori is initially implanted in the mucus layer covered by the epithelium on the surface of the gastric mucosa. It then selectively adheres to the cytoplasm of the surface mucus cells, which makes the oval and spherical particles containing mucus that is wrapped by the bounded membrane in the cytoplasm on the nucleus of the surface mucus cells disappear, while the cytoplasm undergoes spiderweb-like vacuolar degeneration. This leads to the proliferation and transformation of the surface mucous cells before developing into intraepithelial neoplasia. In the process of histomorphology, mucosal ulcers, mucosal lymphoid tissue proliferation, gland atrophy, intestinal epithelial metaplasia, mucosa-associated lymphoid tissue lymphoma, and adenocarcinoma may occur. In this study, the condition was divided into five stages according to the histopathological characteristics of gastric mucosal damage caused by Hp infection, as well as the degree of gastric mucosal damage and involvement depth as follows: the mucus infection stage, the surface epithelial cell infection stage, the lamina propria lesion stage, the mucosal atrophy stage, and the intraepithelial neoplasia stage.

Conclusion

Understanding the histopathological characteristics of gastric Hp infection in terms of its occurrence and development into intraepithelial neoplasia is conducive to the precise treatment and tracking of malignant cell transformation, and is of great significance in controlling the occurrence and development of gastric cancer.

Extra-Nodal Lymphomas of the Head and Neck and Oral Cavity: A Retrospective Study

Disease Overview: Lymphomas, both Hodgkin's and non-Hodgkin's lymphomas, are one of the most common cancers in the head and neck area. The extra-nodal variant of lymphoma is rare, but it is the most common non-Hodgkin's lymphoma (ENHL). Furthermore, it is difficult to diagnose due to its non-specific clinical and radiological features, which can mimic other benign or malignant clinical manifestations. The study: This retrospective study involved 72 patients affected by head and neck ENHL in the period between 2003 and 2017. All patients underwent a diagnostic-therapeutic procedure according to the guidelines, and a 5-year follow-up. Based on the location of the swelling at the time of diagnosis, patients were divided into two groups: oral and non-oral ENHLs. Statistical analysis was performed using Kaplan-Meier analysis with the log-rank test. In addition, Fisher's exact test was applied to the two groups to evaluate and compare variances (the acceptable significance level was set at p < 0.05). Conclusion: ENHL with oral localization is much more aggressive than ENHL with non-oral localization, with a death rate of 40% (versus 4.76 for the non-oral one). In fact, between the two groups, there is a statistically significant difference in mortality, with a p-value of 0.0001 and 0.0002, respectively.

Rare primary rectal mucosa-associated lymphoid tissue lymphoma with curative resection by endoscopic submucosal dissection: A case report and review of literature

BACKGROUND

Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) occurs in approximately 9% of non-Hodgkin B-cell lymphomas. The gastrointestinal tract is the most commonly affected site of the extranodal forms of primary non-Hodgkin’s lymphomas. However, it rarely occurs within the rectum, and at present, there is no consensus on its diagnosis and treatment at this site.

CASE SUMMARY

We report a rare laterally spreading tumour-like rectal MALT lymphoma case in which the diagnosis and the depth of infiltration were determined by magnifying endoscopy and ultrasonic endoscopy. Then, the lesion was en bloc resected by endoscopic submucosal dissection (ESD) alone. The lesion was confirmed as MALT lymphoma by haematoxylin and eosin staining, immunohistochemical staining and gene arrangement analysis. Surveillance exams have indicated a 2-year disease-free survival for this patient.

CONCLUSION

We report a rare primary rectal MALT lymphoma that was curable with resection by ESD. ESD is a safe and effective therapeutic option for rectal MALT lymphoma.

The effects of Helicobacter pylori eradication therapy on salivary pepsin concentration in patients with laryngopharyngeal reflux

OBJECTIVE

To investigate the effect of Helicobacter pylori (HP) eradication therapy on salivary pepsin concentration in laryngopharyngeal reflux (LPR) patients with HP infection.

MATERIALS AND METHODS

A total of 477 patients with suspected LPR were enrolled from June 2020 to September 2021. Reflux symptom index, reflux finding score, the positive rates and disintegrations per minute values of HP infection detected by ¹⁴C urea breath test and salivary pepsin concentrations analyzed using enzyme-linked immunosorbent assay were compared in LPR patients and non-LPR patients with or without HP infection. HP-positive patients were treated with HP eradication therapy while HP-negative patients with PPI therapy.

RESULTS

The scores of nagging cough (0.88 vs. 0.50, P = 0.035), erythema or hyperemia (1.93 vs. 1.78, P = 0.035) and vocal fold edema (1.04 vs. 0.85, P = 0.025) were higher in the LPR (+) Hp (+) subgroup than in LPR (+) Hp (-) subgroup. The concentrations of salivary pepsin in the Hp (+) subgroup were higher than in the Hp (-) subgroup either in LPR patients (75.24 ng/ml vs. 61.39 ng/ml, P = 0.005) or the non-LPR patients (78.42 ng/ml vs. 48.96 ng/ml, P = 0.024). Compared to baseline (before treatment), scores of nagging cough (0.35 vs. 0.84, P = 0.019) and erythema or hyperemia (1.50 vs. 1.83, P = 0.039) and the concentrations of salivary pepsin (44.35 ng/ml vs. 74.15 ng/ml, P = 0.017) in LPR patients with HP infection decreased after HP treatment; yet, this was not observed for the LPR patients without HP infection treated with PPI only (P > 0.05).

CONCLUSION

HP infection may aggravate the symptoms and signs of LPR patients, partly by increasing their salivary pepsin concentration.

Analysis of Lymphoma-Related Genes with Gene Ontology and Kyoto Encyclopedia of Genes and Genomes Enrichment

Lymphoma is a serious malignant tumor that contains more than 70 different types and seriously endangers the body's lymphatic system. The lymphatic system is the regulatory center of the immune system and is important in the immune response to foreign antigens and tumors. Studies showed that multiple genetic variants are associated with lymphoma but determining the pathogenic mechanisms remains a challenge. In the present study, we first applied the Gene Ontology (GO) and KEGG pathway enrichment analyses of lymphoma-associated and lymphoma-nonassociated genes. Next, the Boruta and max-relevance and min-redundancy feature selection methods were performed to filter and rank features. Then, features preselected and ranked using the incremental feature selection method were applied for the decision tree model to identify the best GO terms and KEGG pathways and extract classification rules. Results indicate that our predicted features, such as B-cell activation, negative regulation of protein processing, negative regulation of mast cell cytokine production, and natural killer cell-mediated cytotoxicity, are associated with the biological process of lymphoma, consistent with those of recent publications. This study provides a new perspective for future research on the molecular mechanisms of lymphoma.

Gastrointestinal microbiome and Helicobacter pylori: Eradicate, leave it as it is, or take a personalized benefit-risk approach?

Helicobacter pylori (H. pylori) is generally regarded as a human pathogen and a class 1 carcinogen, etiologically related to gastric and duodenal ulcers, gastric cancer, and mucosa-associated lymphoid tissue lymphoma. However, H. pylori can also be regarded as a commensal symbiont. Unlike other pathogenic/ opportunistic bacteria, H. pylori colonization in infancy is facilitated by T helper type 2 immunity and leads to the development of immune tolerance. Fucosylated gastric mucin glycans, which are an important part of the innate and adaptive immune system, mediate the adhesion of H. pylori to the surface of the gastric epithelium, contributing to successful colonization. H. pylori may have beneficial effects on the host by regulating gastrointestinal (GI) microbiota and protecting against some allergic and autoimmune disorders and inflammatory bowel disease. The potential protective role against inflammatory bowel disease may be related to both modulation of the gut microbiota and the immunomodulatory properties of H. pylori. The inverse association between H. pylori and some potentially proinflammatory and/or procarcinogenic bacteria may suggest it regulates the GI microbiota. Eradication of H. pylori can cause various adverse effects and alter the GI microbiota, leading to short-term or long-term dysbiosis. Overall, studies have shown that gastric Actinobacteria decrease after H. pylori eradication, Proteobacteria increase during short-term follow-up and then return to baseline levels, and Enterobacteriaceae and Enterococcus increase in the short-term and interim follow-up. Various gastric mucosal bacteria (Actinomyces, Granulicatella, Parvimonas, Peptostreptococcus, Prevotella, Rothia, Streptococcus, Rhodococcus, and Lactobacillus) may contribute to precancerous gastric lesions and cancer itself after H. pylori eradication. H. pylori eradication can also lead to dysbiosis of the gut microbiota, with increased Proteobacteria and decreased Bacteroidetes and Actinobacteria. The increase in gut Proteobacteria may contribute to adverse effects during and after eradication. The decrease in Actinobacteria, which are pivotal in the maintenance of gut homeostasis, can persist for > 6 mo after H. pylori eradication. Furthermore, H. pylori eradication can alter the metabolism of gastric and intestinal bacteria. Given the available data, eradication cannot be an unconditional recommendation in every case of H. pylori infection, and the decision to eradicate H. pylori should be based on an assessment of the benefit-risk ratio for the individual patient. Thus, the current guidelines based on the unconditional "test-and-treat" strategy should be revised. The most cautious and careful approach should be taken in elderly patients with multiple eradication failures since repeated eradication can cause antibiotic-associated diarrhea, including severe Clostridioides difficile-associated diarrhea and colitis and antibiotic-associated hemorrhagic colitis due to Klebsiella oxytoca. Furthermore, since eradication therapy with antibiotics and proton pump inhibitors can lead to serious adverse effects and/or dysbiosis of the GI microbiota, supplementation of probiotics, prebiotics, and microbial metabolites (e.g., butyrate + inulin) should be considered to decrease the negative effects of eradication.

Follow-up analysis and histopathological study of gastric mucosa in patients with Helicobacter pylori infection

Objective

To investigate the histomorphological characteristics of the gastric mucosa and the prognosis in patients with Helicobacter pylori infection.

Methods

Progressive damage to the gastric mucosa was examined by immunohistochemistry in 2294 patients with H. pylori infection and follow-up information was analyzed.

Results

H. pylori initially colonized the mucus layer covered by the gastric mucosa epithelium, then selectively adhered to and destroyed the surface mucus cells causing intra-gastric and extra-gastric lesions. Gastric mucosal damage induced by H. pylori was divided into five stages according to the depth of H. pylori invasion and degree of lesion deterioration: mucilaginous, surface mucocellular, lamina propria lesion, mucosal atrophy, and intraepithelial neoplasia stages. Morphological follow-up analysis revealed no significant difference in 6-month curative effects between stage I and stage II, but significant differences were found between stages II and III, stages III and IV, and between stages IV and stage V, respectively.

Conclusions

This novel staging strategy may be a valuable tool for diagnosing and predicting the results of gastric mucosal damage induced by H. pylori infection.

A Random Walk-Based Method to Identify Candidate Genes Associated With Lymphoma

Lymphoma is a serious type of cancer, especially for adolescents and elder adults, although this malignancy is quite rare compared with other types of cancer. The cause of this malignancy remains ambiguous. Genetic factor is deemed to be highly associated with the initiation and progression of lymphoma, and several genes have been related to this disease. Determining the pathogeny of lymphoma by identifying the related genes is important. In this study, we presented a random walk-based method to infer the novel lymphoma-associated genes. From the reported 1,458 lymphoma-associated genes and protein–protein interaction network, raw candidate genes were mined by using the random walk with restart algorithm. The determined raw genes were further filtered by using three screening tests (i.e., permutation, linkage, and enrichment tests). These tests could control false-positive genes and screen out essential candidate genes with strong linkages to validate the lymphoma-associated genes. A total of 108 inferred genes were obtained. Analytical results indicated that some inferred genes, such as RAC3, TEC, IRAK2/3/4, PRKCE, SMAD3, BLK, TXK, PRKCQ, were associated with the initiation and progression of lymphoma.

Therapeutic Influence on Important Targets Associated with Chronic Inflammation and Oxidative Stress in Cancer Treatment

Chronic inflammation and oxidative stress are the interconnected pathological processes, which lead to cancer initiation and progression. The growing level of oxidative and inflammatory damage was shown to increase cancer severity and contribute to tumor spread. The overproduction of reactive oxygen species (ROS), which is associated with the reduced capacity of the endogenous cell defense mechanisms and/or metabolic imbalance, is the main contributor to oxidative stress. An abnormal level of ROS was defined as a predisposing factor for the cell transformation that could trigger pro-oncogenic signaling pathways, induce changes in gene expression, and facilitate accumulation of mutations, DNA damage, and genomic instability. Additionally, the activation of transcription factors caused by a prolonged oxidative stress, including NF-κB, p53, HIF1α, etc., leads to the expression of several genes responsible for inflammation. The resulting hyperactivation of inflammatory mediators, including TNFα, TGF-β, interleukins, and prostaglandins can contribute to the development of neoplasia. Pro-inflammatory cytokines were shown to trigger adaptive reactions and the acquisition of resistance by tumor cells to apoptosis, while promoting proliferation, invasion, and angiogenesis. Moreover, the chronic inflammatory response leads to the excessive production of free radicals, which further aggravate the initiated reactions. This review summarizes the recent data and progress in the discovery of mechanisms that associate oxidative stress and chronic inflammation with cancer onset and metastasis. In addition, the review provides insights for the development of therapeutic approaches and the discovery of natural substances that will be able to simultaneously inhibit several key oncological and inflammation-related targets.

Vaccine development against Helicobacter pylori: from ideal antigens to the current landscape

Introduction: The interest of the world scientific community for an effective vaccine against Helicobacter pylori infection arises from its high prevalence and association with many diseases. Moreover, with an immunological response that is not always effective for the eradication of the bacteria and an increasing antibiotic resistance in the treatment of this infection, the search for a vaccine and new therapeutic modalities to control this infection is urgent.Areas covered: We bring an overview of the infection worldwide, discussing its prevalence, increasing resistance to antibiotics used in its therapy, in addition to the response of the immune system to the infection registered so far. Moreover, we address the most used antigens and their respective immunological responses expected or registered up to now. Finally, we address the trials and their partial results in development for such vaccines.Expert opinion: Although several studies for the development of an effective vaccine against this pathogen are taking place, many are still in the preclinical phase or even without updated information. In this sense, taking into account the high prevalence and association with important comorbidities, the interest of the pharmaceutical industry in developing an effective vaccine against this pathogen is questioned.

Department of biology, Faculty of Science, University of Kufa, Iraq, Muhammad Rashad JMB, Jaloob Aljanaby AAJ, Department of biology, Faculty of Science, University of Kufa, Iraq. ROLE OF INTERLEUKIN-2, INTERLEUKIN-4 AND CLUSTER OF DIFFERENTIATION-22 AS AN IMMUNE MARKERS IN INDIVIDUALS INFECTED WITH Helicobacter pylori

Helicobacter pylori is a gram-negative, intracellular, microaerophilic bacteria which causing Peptic ulcer. This bacterium can change its shape which helps the bacteria to survive in the host gastric microenvironment. The Peptic ulcer caused by this bacterium stimulates the humoral and cellular immune response in individuals. The current study was carried out to access the role of interleukin-2, interleukin-4, and cluster differentiation-22 as immune markers in the identification of H. pylori infection. The presence of H. pylori has been diagnosed by feces test (antigen rapid test). In this study, the presence of three immunological markers viz., IL-2, IL-4, and CD22 were measured in the serum of 60 individuals infected with H. pylori and 30 healthy individuals by the Enzyme-Linked Immune-sorbent Assay method. Results of this study indicated a significant increase (P-value=0.0307*) in the concentration of IL-2 (294.27ng/ml), IL-4(151.28ng/ml), and CD22 (492.73ng/ml) in the serum of individuals infected with H. pylori while these concentrations were reported 235.98ng/ml, 116.14ng/ml and 369.33ng/ml respectively in the healthy individuals. Results of the study can be concluded that H.pylori infection stimulates the Cellular and humoral immune response which resulted in the increased production of IL-2, IL-4, and CD22.

Rituximab-induced Ileocolitis in a Patient with Gastric MALToma: A Case Report and Literature Review

Rituximab (RTX) is effective for treating cancer, but reports of RTX-associated enterocolitis are limited. We herein report the case of a 65-year-old man who developed RTX-induced ileocolitis. He was diagnosed with gastric mucosa-associated lymphoid tissue lymphoma (MALToma) and treated with RTX. He complained of bloody diarrhea after RTX. Mucosal inflammation on colonoscopy indicated RTX-induced ileocolitis. He was treated with corticosteroids, and his symptoms improved. We reviewed the RTX-associated gastrointestinal adverse events and classified the features into ulcerative colitis, Crohn's disease, microscopic colitis, and ileocolitis. To our knowledge, this is the first case of a Japanese patient who developed RTX-induced ileocolitis.

Tumor-Associated Microbiome: Where Do We Stand?

The study of the human microbiome in oncology is a growing and rapidly evolving field. In the past few years, there has been an exponential increase in the number of studies investigating associations of microbiome and cancer, from oncogenesis and cancer progression to resistance or sensitivity to specific anticancer therapies. The gut microbiome is now known to play a significant role in antitumor immune responses and in predicting the efficacy of immune-checkpoint inhibitors in cancer patients. Beyond the gut, the tumor-associated microbiome-microbe communities located either in the tumor or within its body compartment-seems to interact with the local microenvironment and the tumor immune contexture, ultimately impacting cancer progression and treatment outcome. However, pre-clinical research focusing on causality and mechanistic pathways as well as proof-of-concept studies are still needed to fully understand the potential clinical utility of microbiome in cancer patients. Moreover, there is a need for the standardization of methodology and the implementation of quality control across microbiome studies to allow for a better interpretation and greater comparability of the results reported between them. This review summarizes the accumulating evidence in the field and discusses the current and upcoming challenges of microbiome studies.

Radiotherapy for non-gastric intestinal versus gastric MALT lymphoma: a comparison of treatment outcomes

Background

Radiotherapy is often used for treating patients with gastric mucosa-associated lymphoid tissue (MALT) lymphomas who fail to respond to Helicobacter pylori eradication. However, non-gastric intestinal MALT lymphoma is rare, and no standard therapeutic strategies have been established. This study was designed to assess the long-term prognosis of non-gastric intestinal MALT lymphoma treated with radiotherapy and to compare the outcomes with that of post-radiotherapy gastric MALT lymphoma.

Methods

The study included 34 patients with stage I EA gastrointestinal MALT lymphoma according to the Ann Arbor classification who underwent definitive radiotherapy. The primary site was the rectum in 3, the duodenum in 1, and the stomach in 30 patients. The radiotherapy dose was 1.5‒2.0 Gy (median, 1.5 Gy) and the total dose was 30‒40 Gy (median, 30 Gy). The clinical target volume (CTV) was defined as the volume of the entire organ with the lymphoma. Adjacent lymph node areas were not routinely included in the CTV.

Results

Complete response (CR) was achieved in all patients. There were no local recurrences, and two cases of recurrence were observed at other sites. The 5-year overall survival rates for non-gastric and gastric MALT lymphomas were 100% and 94.7%, respectively, and the 5-year disease-free survival rates were 100% and 95.7%, respectively. None of the patients died of the current illness.

Conclusion

Radiotherapy for non-gastric intestinal MALT lymphoma is expected to result in good local control and long-term survival, similar to that for gastric MALT lymphoma.

Colonic Mucosa-associated Lymphoid Tissue Lymphoma Treated by Radiation Therapy: Report of a Case and Literature Review

Mucosa-associated lymphoid tissue (MALT) lymphoma predominantly involves the gastrointestinal tract, with the stomach being the most commonly affected site. Colonic involvement is quite rare. Hence, the etiology, clinical characteristics, treatment, and outcome of colonic MALT lymphoma are not well established. This paper reports a case of MALT lymphoma of the transverse colon, presenting as a subepithelial tumor in a 50-year-old woman. The patient received 3,060 cGy in 17 fractions with external beam radiation therapy for three weeks. At 2 months after radiation therapy, a colonoscopy examination revealed complete resolution and a scar change of the lesion. The follow-up at 24 months revealed no evidence of tumor recurrence after radiation therapy.

How does Helicobacter pylori cause gastric cancer through connexins: An opinion review

Helicobacter pylori (H. pylori) is a Gram-negative bacterium with a number of virulence factors, such as cytotoxin-associated gene A, vacuolating cytotoxin A, its pathogenicity island, and lipopolysaccharide, which cause gastrointestinal diseases. Connexins function in gap junctional homeostasis, and their downregulation is closely related to gastric carcinogenesis. Investigations into H. pylori infection and the fine-tuning of connexins in cells or tissues have been reported in previous studies. Therefore, in this review, the potential mechanisms of H. pylori-induced gastric cancer through connexins are summarized in detail.