A Possible Link between Gastric Mucosal Atrophy and Gastric Cancer after Helicobacter pylori Eradication

FZHWT alleviates chronic atrophic gastritis by inhibiting inflammatory pathways and promoting mucosal repair

BACKGROUND

Chronic atrophic gastritis (CAG) is a prevalent chronic digestive disorder that, through sustained inflammation, can lead to severe mucosal damage and even gastric cancer. Current treatments offer limited efficacy, whereas Fu-Zheng-Huo-Wei Decoction (FZHWT), a traditional Chinese medicine (TCM) formulation, shows promising potential in treating CAG.

PURPOSE

This study aims to identify the key active components of FZHWT and evaluate its therapeutic effects on CAG.

METHODS

UPLC-MS/MS was used to identify the bioactive compounds in FZHWT. A CAG rat model was established to assess its therapeutic effects, and transcriptome sequencing was conducted to identify key targets and mechanisms. A CAG cell model was used for validation of the transcriptomic findings, and histological techniques and molecular biology methods were employed for further validation.

RESULTS

A total of 1362 chemical components were identified in FZHWT, of which 25 are bioavailable compounds. Differential metabolite analysis revealed four key active ingredients: Nicotiflorin, Stachydrine, 5-O-p-Coumaroylquinic acid, and N-(4-oxopentyl)-acetamide. In the CAG rat model, FZHWT significantly reduced inflammation and gastric mucosal damage. Transcriptome sequencing highlighted Sema5a as a key target and revealed the involvement of several inflammatory signaling pathways. In the CAG cell model, FZHWT alleviated CAG by inhibiting inflammation and promoting gastric mucosal repair.

CONCLUSIONS

FZHWT demonstrates significant therapeutic potential in treating CAG by modulating inflammatory pathways and promoting mucosal repair. This study provides new insights into the treatment of CAG and supports the modernization of multi-component TCM formulas.

Helicobacter pylori and Gastrointestinal Cancers: Recent Advances and Controversies

Helicobacter pylori (H pylori), a gastric bacterium, has been extensively studied for its association with gastritis, peptic ulcers, and gastric cancer. However, recent evidence suggests its potential implications beyond the stomach, linking it to other gastrointestinal malignancies, such as esophageal cancer, liver cancer, pancreatic cancer, gallbladder cancer, and colorectal cancer. In light of the expanding research landscape and the increasing interest in exploring H pylori broader role in gastrointestinal tumorigenesis, this comprehensive review aims to elucidate the relationship between H pylori and gastrointestinal tumors. This review encompasses recent epidemiological studies, research progress, and emerging perspectives, providing a comprehensive assessment of the relationship between H pylori and gastrointestinal tumors. The findings highlight the captivating world of H pylori and its intricate involvement in gastrointestinal malignancies.

An explainable artificial intelligence system for diagnosing Helicobacter Pylori infection under endoscopy: a case-control study

BACKGROUND

Changes in gastric mucosa caused by Helicobacter pylori (H. pylori) infection affect the observation of early gastric cancer under endoscopy. Although previous researches reported that computer-aided diagnosis (CAD) systems have great potential in the diagnosis of H. pylori infection, their explainability remains a challenge.

OBJECTIVE

We aim to develop an explainable artificial intelligence system for diagnosing H. pylori infection (EADHI) and giving diagnostic basis under endoscopy.

DESIGN

A case-control study.

METHODS

We retrospectively obtained 47,239 images from 1826 patients between 1 June 2020 and 31 July 2021 at Renmin Hospital of Wuhan University for the development of EADHI. EADHI was developed based on feature extraction combining ResNet-50 and long short-term memory networks. Nine endoscopic features were used for H. pylori infection. EADHI's performance was evaluated and compared to that of endoscopists. An external test was conducted in Wenzhou Central Hospital to evaluate its robustness. A gradient-boosting decision tree model was used to examine the contributions of different mucosal features for diagnosing H. pylori infection.

RESULTS

The system extracted mucosal features for diagnosing H. pylori infection with an overall accuracy of 78.3% [95% confidence interval (CI): 76.2-80.3]. The accuracy of EADHI for diagnosing H. pylori infection (91.1%, 95% CI: 85.7-94.6) was significantly higher than that of endoscopists (by 15.5%, 95% CI: 9.7-21.3) in internal test. And it showed a good accuracy of 91.9% (95% CI: 85.6-95.7) in external test. Mucosal edema was the most important diagnostic feature for H. pylori positive, while regular arrangement of collecting venules was the most important H. pylori negative feature.

CONCLUSION

The EADHI discerns H. pylori gastritis with high accuracy and good explainability, which may improve the trust and acceptability of endoscopists on CADs.

PLAIN LANGUAGE SUMMARY

An explainable AI system for Helicobacter pylori with good diagnostic performance Helicobacter pylori (H. pylori) is the main risk factor for gastric cancer (GC), and changes in gastric mucosa caused by H. pylori infection affect the observation of early GC under endoscopy. Therefore, it is necessary to identify H. pylori infection under endoscopy. Although previous research showed that computer-aided diagnosis (CAD) systems have great potential in H. pylori infection diagnosis, their generalization and explainability are still a challenge. Herein, we constructed an explainable artificial intelligence system for diagnosing H. pylori infection (EADHI) using images by case. In this study, we integrated ResNet-50 and long short-term memory (LSTM) networks into the system. Among them, ResNet50 is used for feature extraction, LSTM is used to classify H. pylori infection status based on these features. Furthermore, we added the information of mucosal features in each case when training the system so that EADHI could identify and output which mucosal features are contained in a case. In our study, EADHI achieved good diagnostic performance with an accuracy of 91.1% [95% confidence interval (CI): 85.7-94.6], which was significantly higher than that of endoscopists (by 15.5%, 95% CI: 9.7-21.3%) in internal test. In addition, it showed a good diagnostic accuracy of 91.9% (95% CI: 85.6-95.7) in external tests. The EADHI discerns H. pylori gastritis with high accuracy and good explainability, which may improve the trust and acceptability of endoscopists on CADs. However, we only used data from a single center to develop EADHI, and it was not effective in identifying past H. pylori infection. Future, multicenter, prospective studies are needed to demonstrate the clinical applicability of CADs.

Evolution of the Correa's cascade steps: A long-term endoscopic surveillance among non-ulcer dyspepsia and gastric ulcer after H. pylori eradication

BACKGROUND

This study is aimed toward investigating the evolution of each Correa's step after Helicobacter pylori eradication in a long-term follow-up and exploring the factors correlated with a high-risk of gastric cancer.

METHODS

A total of 1824 H. pylori-infected subjects were enrolled to receive screening endoscopy. Among them, 491 received surveillance endoscopy. The patients were divided into Correa's steps I to VI, from normal to gastric cancer. A group-based trajectory model was used to classify patients as persistent high-risk status or not.

RESULTS

The prevalence rates of positive corpus-predominant gastritis index (CGI) were 20%-40% in all age groups and Correa's steps IV-V increased >35% after 50 years based on screening endoscopy. Successful eradication of H. pylori regressed CGI after the 1st year-and-thereafter (P < 0.05) and decreased Correa's step progression (Relative risk 0.66 [95% CI 0.49-0.89], P = 0.01); however, it did not regress OLGA and OLGIM. Not only in steps IV-V, but also in step III, the patients had a risk of developing gastric cancer (11.13-76.41 and 4.61 per 1000 person-years). Age (Hazard ratio 1.012 [1.003-1.020], P = 0.01), OLGA stages ≥ I (2.127 [1.558-2.903], P < 0.001), and OLGIM stages ≥ I (1.409 [1.119-1.774], P = 0.004) were correlated independently with a persistent high-risk status.

CONCLUSION

The patients in Correa's steps III-V, but not I-II, were at risk of gastric cancer after H. pylori eradication. Age, OLGA stages ≥ I, and OLGIM stages ≥ I were independent factors correlated to a persistent high-risk of gastric cancer. The data may be useful when scheduling surveillance endoscopy for subjects in each Correa's step (NCT04527055).

Gastric epithelial histology and precancerous conditions

The most common histological type of gastric cancer (GC) is gastric adenocarcinoma arising from the gastric epithelium. Less common variants include mesenchymal, lymphoproliferative and neuroendocrine neoplasms. The Lauren scheme classifies GC into intestinal type, diffuse type and mixed type. The WHO classification includes papillary, tubular, mucinous, poorly cohesive and mixed GC. Chronic atrophic gastritis (CAG) and intestinal metaplasia are recommended as common precancerous conditions. No definite precancerous condition of diffuse/poorly/undifferentiated type is recommended. Chronic superficial inflammation and hyperplasia of foveolar cells may be the focus. Presently, the management of early GC and precancerous conditions mainly relies on endoscopy including diagnosis, treatment and surveillance. Management of precancerous conditions promotes the early detection and treatment of early GC, and even prevent the occurrence of GC. In the review, precancerous conditions including CAG, metaplasia, foveolar hyperplasia and gastric hyperplastic polyps derived from the gastric epithelium have been concluded, based on the overview of gastric epithelial histological organization and its renewal.

Chronic inflammation and long-lasting changes in the gastric mucosa after Helicobacter pylori infection involved in gastric cancer

OBJECTIVE

Helicobacter pylori (H. pylori) infects approximately half of the world's population, as one of the most common chronic infections. H. pylori infection has been widely recognized as a major risk factor for gastric cancer (GC).

METHODS

Eradication treatment is considered to abolish the inflammatory response and prevent progression to GC. However, only 1-3% of H. pylori-infected patients develop GC, whereas GC can occur even after eradicating H. pylori. In addition, the incidence of GC following H. pylori infection is significantly higher compared to the gross incidence induced by all causes, although eradicating H. pylori reduces the risk of developing GC.

RESULTS

Therefore, it is reasonable to hypothesize that H. pylori infection results in changes that persist even after its eradication. Several of these changes may not be reversible within a short time, including the status of inflammation, the dysfunction of immunity and apoptosis, mitochondrial changes, aging and gastric dysbacteriosis.

CONCLUSION

The present review article aimed to discuss these potential long-lasting changes induced by H. pylori infection that may follow the eradication of H. pylori and contribute to the development of GC.

Therapeutic effects of placenta derived-, umbilical cord derived-, and adipose tissue derived-mesenchymal stem cells in chronic Helicobacter pylori infection: comparison and novel mechanisms

Supported with significant rejuvenating and regenerating actions of mesenchymal stem cells (MSCs) in various gastrointestinal diseases including Helicobacter pylori (H. pylori)-associated gastric diseases, we have compared these actions among placenta derived-MSCs (PD-MSCs), umbilical cord derived-MSCs (UC-MSCs), and adipose tissue derived-MSCs (AD-MSCs) and explored contributing genes implicated in rejuvenation of H. pylori-chronic atrophic gastritis (CAG) and tumorigenesis. In this study adopting H. pylori-initiated, high salt diet-promoted gastric carcinogenesis model, we have administered three kinds of MSCs around 15-18 weeks in H. pylori infected C57BL/6 mice and sacrificed at 24 and 48 weeks, respectively, in order to either assess the rejuvenating capability or anti-tumorigenesis. At 24 weeks, MSCs all led to significantly mitigated atrophic gastritis, for which significant inductions of autophagy, preservation of tumor suppressive 15-PGDH, attenuated apoptosis, and efficient efferocytosis was imposed with MSCs administration during atrophic gastritis. At 48 weeks, MSCs administered during H. pylori-associated atrophic gastritis afforded significant blocking the progression of CAG, as evidenced with statistically significant reduction in H. pylori-associated gastric tumor (p<0.05) accompanied with significant decreases in IL-1β, COX-2, STAT3, and NF-κB. Combined together with the changes of stanniocalcin-1 (STC-1), thrombospondin-1 (TSP-1), and IL-10 known as biomarkers reflecting stem cell activities at 48 weeks after H. pylori, PD-MSCs among MSCs afforded the best rejuvenating action against H. pylori-associated CAG via additional actions of efferocytosis, autophagy, and anti-apoptosis at 24 weeks. In conclusion, MSCs, especially PD-MSCs, exerted rejuvenating actions against H. pylori-associated CAG via anti-mutagenesis of IL-10, CD-36, ATG5 and cancer suppressive influences of STC-1, TSP-1, and 15-PGDH.

Characteristics and Early Diagnosis of Gastric Cancer Discovered after Helicobacter pylori Eradication

The prevalence of gastric cancer after eradication (GCAE) is increasing dramatically in Japan. GCAE has characteristic features, and we must understand these features in endoscopic examinations. Differentiated cancer types were frequently found after eradication and included characteristic endoscopic features such as reddish depression (RD). However, benign RD can be difficult to distinguish from gastric cancer because of histological alterations in the surface structures (nonneoplastic epithelium or epithelium with low-grade atypia [ELA]) as well as multiple appearances of RD. Recently, we clarified similar alterations in genetic mutations between ELA and gastric cancer, suggesting that ELA is derived from gastric cancer. Clinically, submucosal invasive cancer was frequently found in patients after eradication therapy even if they received annual endoscopic surveillance. We can improve the diagnostic ability using image-enhanced endoscopy with magnified observation.

The Role and Impact of Deep Learning Methods in Computer-Aided Diagnosis Using Gastrointestinal Endoscopy

At present, the application of artificial intelligence (AI) based on deep learning in the medical field has become more extensive and suitable for clinical practice compared with traditional machine learning. The application of traditional machine learning approaches to clinical practice is very challenging because medical data are usually uncharacteristic. However, deep learning methods with self-learning abilities can effectively make use of excellent computing abilities to learn intricate and abstract features. Thus, they are promising for the classification and detection of lesions through gastrointestinal endoscopy using a computer-aided diagnosis (CAD) system based on deep learning. This study aimed to address the research development of a CAD system based on deep learning in order to assist doctors in classifying and detecting lesions in the stomach, intestines, and esophagus. It also summarized the limitations of the current methods and finally presented a prospect for future research.

Use of endoscopic assessment of gastric atrophy for gastric cancer risk stratification to reduce the need for gastric mapping

Background/Aims: Stratification for gastric cancer risk typically involves histologic grading of gastric biopsies. This study aimed to compare endoscopic assessment of gastric atrophy and histologic gastric mapping for gastric cancer risk stratification in a region with relatively high risk of gastric cancer.Methods: Endoscopic and histologic gastric cancer risk stratification were compared in Vietnamese patients with functional dyspepsia. Endoscopic gastric atrophy was graded according to the Kimura-Takemoto classification. High-risk histologic lesions were defined as gastric dysplasia, Operative Link on Gastritis Assessment (OLGA) gastritis stage III/IV, intestinal metaplasia in both the antrum and the corpus or incomplete intestinal subtype at any site. Two experienced pathologists, blinded to endoscopic information, jointly examined all specimens and reached a consensus. The presence of high-risk histologic lesions was compared among patients with different endoscopic grades of gastric atrophy.Results: There were 280 subjects (mean age, 46.1 ± 10 years, and male, 50%). The numbers of patients with moderate/severe grade of endoscopic gastric atrophy and high-risk histologic lesions were 126 (45.0%) and 46 (16.4%), respectively. The sensitivity, specificity, positive and negative likelihood ratios of moderate/severe endoscopic atrophic grade for detecting high-risk histologic lesions were 93% (95% CI 86%-100%), 65% (95% CI 58%-71%), 2.64 (95% CI 2.18 - 3.18) and 0.10 (95% CI 0.03 - 0.30), respectively.Conclusions: Gastric cancer risk assessment using endoscopic or histologic methods provided similar results such that the absence or a mild grade of endoscopic gastric atrophy would preclude the need for histologic mapping.

Gastric cancer and gastrin: on the interaction of Helicobacter pylori gastritis and acid inhibitory induced hypergastrinemia

Gastric cancer, a disease with a reduced frequency for decades, now appears to be on the rise again in young Americans. The epidemiology of gastric cancer differs between tumors in the cardia and those of the more distal parts of the stomach. The tumors are divided into the intestinal type showing glandular growth pattern and the diffuse type with a different pattern. The latter often expresses neuroendocrine and more specifically ECL-cell markers suggesting that they originate from the ECL cell, the target cell for the antral hormone, gastrin. Helicobacter pylori gastritis is accepted as the major cause of gastric cancer, but only after having induced oxyntic atrophy which reduces gastric acid secretion and thus induces hypoacidity leading to hypergastrinemia. Long-term hypergastrinemia is known to induce malignant neoplasia in the stomach of animals as well as man. Recently treatment with proton pump inhibitor after Helicobacter pylori eradication in patients with gastroesophageal reflux disease, has been reported to predispose to gastric cancer. Since profound acid inhibition is a well-known cause of gastric neoplasia, it is to be expected that Helicobacter pylori infection and profound acid inhibition has an additive or possibly potentiating effect on the development of gastric cancer.

Assessment of Endoscopic Gastric Atrophy according to the Kimura-Takemoto Classification and Its Potential Application in Daily Practice

The assessment of endoscopic gastric atrophy (EGA) according to the Kimura-Takemoto classification has been reported to correlate well with histological assessment. Although agreement among beginner endoscopists was less than that among experienced endoscopists, it has been shown that agreement level could markedly improve and remained stable after proper training. Several cohort studies have consistently shown that the severity of EGA at baseline is significantly associated with the presence of advanced precancerous gastric lesions and gastric cancer, as well as the development of gastric cancer in future. Patients with moderate-to-severe EGA still have high risk of gastric cancer even after successful Helicobacter pylori eradication and should be candidates for gastric cancer surveillance. The assessment of EGA, therefore, could be used as a preliminary tool to identify individuals at high risk for gastric cancer. In this paper, we review the agreement on mucosal atrophy assessment between the Kimura-Takemoto classification and histology as well as the potential application of this endoscopic classification to identify precancerous gastric lesions and gastric cancer in daily practice.

DNA methylation accumulation in gastric mucosa adjacent to cancer after Helicobacter pylori eradication

Molecular irreversibleness with Helicobacter pylori (H. pylori) infection might have a role in gastric tumorigenesis after H. pylori eradication. We performed comprehensive DNA methylation profiling of gastric mucosa after H. pylori eradication with or without gastric cancer. Using four different groups of biopsies obtained from gastric body without history of H. pylori infection (Hp-), gastric body without cancer after H. pylori eradication (cancer-free body), gastric body with early gastric cancer diagnosed after H. pylori eradication (EGC body) and their paired samples from adjacent mucosa of cancer (EGC ADJ), methylation status of five candidate genes (MYOD1, SLC16A12, IGF2, RORA and PRDM5) was examined by the bisulfite pyrosequencing. An Infinium Methylation EPIC BeadChip array was also used to characterize the methylation status of greater than 850,000 CpG sites. The EGC ADJ group showed highest methylation levels of five candidate genes among the four groups of biopsies. In the gastric body (cancer-free body + EGC body), methylation levels were significantly decreased in patients with longer period after eradication, while such association was not observed in EGC ADJ group. Hyper methylated samples were associated with shorter telomere, an indicator for rapid cell turnover, and higher DNMT1 protein expression, an enzyme related to methyl transfer reaction. The genome-wide methylation analysis demonstrated strikingly higher methylation levels especially at CpG islands in the EGC ADJ group. Exclusively hypermethylated promoter CpG islands in the same group frequently coded zinc finger proteins. Our data show that DNA methylation accumulation is associated with molecular irreversibleness and gastric carcinogenesis after H. pylori eradication.

Gastric Cancer Screening by Combined Determination of Serum Helicobacter pylori Antibody and Pepsinogen Concentrations: ABC Method for Gastric Cancer Screening

Objective:

Gastroscopy combined with gastric mucosa biopsies is currently regarded as a gold standard for diagnosis of gastric cancer. However, its application is restricted in clinical practice due to its invasive property. A new noninvasive population screening process combining the assay of anti-Helicobacter pylori antibody and serum pepsinogen (PG) (ABC method) is adopted to recognize the high-risk patients for further endoscopy examination, avoiding the unnecessary gastroscopy for most population and saving the cost consumption for mass screening annually. Nevertheless, controversies exist for the grouping of ABC method and the intervals of gastroscopy surveillance for each group. In this review, we summarized these popular concerned topics for providing useful references to the healthcare practitioner in clinical practice.

Data Sources:

The PubMed databases were systematically searched from the inception dates to November 22, 2017, using the keywords “Helicobacter pylori,” “Pepsinogens,” and “Stomach Neoplasms.”

Study Selection:

Original articles and reviews on the topics were selected.

Results:

Anti-H. pylori antibody and serum PG concentration showed significant changes under the different status of H. pylori infection and the progression of atrophic gastritis, which can be used for risk stratification of gastric cancer in clinic. In addition, anti-H. pylori antibody titer can be used for further risk stratification of gastric cancer contributing to determine better endoscopy surveillance interval.

Conclusions:

The early detection and diagnosis of gastric cancer benefit from the risk stratification, but the cutoff values for H. pylori antibody and serum PG concentration require further modification.

Shenqi Yiwei decoction for treatment of atrophic gastritis of spleen-stomach deficiency cold type: Clinical efficacy and influence on TXB2 and 6-keto-PGF1α

AIM

To evaluate the clinical efficacy of Shenqi Yiwei decoction in the treatment of atrophic gastritis of spleen-stomach deficiency cold type and investigate its influence on TXB₂ and 6-keto-PGF1α.

METHODS

Eighty-six patients with atrophic gastritis of spleen-stomach deficiency cold type were selected from January 2016 to October 2017 at the Third Affiliated Hospital of Zhejiang Chinese Medicine University, and the patients were randomly divided into either an experimental group (n = 43) or a control group (n = 43). The control group was treated with omeprazole, while the experimental group was treated with Shenqi Yiwei decoction. The patients in both groups were treated for 8 wk. The effective rates of the two groups were compared. Main symptom scores (including abdominal distension, dry mouth, anorexia, fatigue, and indigestion), endoscopic scores (including mucosal appearance, mucosal erosion, bile reflux, mucous folds, and blood vessels), TXB₂ and 6-keto-PGF1α, and complications were also compared between the two groups.

RESULTS

The total effective rate was significantly higher in the experimental group than in the control group (95.35% vs 81.40%, χ² = 4.0741, P = 0.0436). Before treatment, abdominal distension, dry mouth, anorexia, fatigue, and indigestion scores were not statistically significant between the two groups (P > 0.05); after treatment, these scored significantly decreased in both groups (P < 0.05), and the decrease was more significant in the experimental group. Before treatment, scores of mucosal appearance, mucosal erosion, bile reflux, mucous folds, and blood vessels were not statistically significant between the two groups (P > 0.05); after treatment, these scores were significantly improved in both groups (P < 0.05), and the improvement was more significant in the experimental group (P < 0.05). Before treatment, TXB₂ and 6-keto-PGF1α differed significantly between the two groups (P > 0.05); after treatment, TXB₂ decreased significantly and 6-keto-PGF1α increased significantly in both groups (P < 0.05), and the changes were more significant in the experimental group (P < 0.05). Adverse reactions such as constipation and vomiting did not occur in either group.

CONCLUSION

Shenqi Yiwei decoction has a good therapeutic effect in atrophic gastritis of spleen-stomach deficiency cold type, and it can significantly reduce clinical symptoms and improve endoscopic changes possibly by regulating TXB₂ and 6-keto-PGF1α.

Deep learning analyzes Helicobacter pylori infection by upper gastrointestinal endoscopy images

BACKGROUND AND STUDY AIMS

Helicobacter pylori (HP)-associated chronic gastritis can cause mucosal atrophy and intestinal metaplasia, both of which increase the risk of gastric cancer. The accurate diagnosis of HP infection during routine medical checks is important. We aimed to develop a convolutional neural network (CNN), which is a machine-learning algorithm similar to deep learning, capable of recognizing specific features of gastric endoscopy images. The goal behind developing such a system was to detect HP infection early, thus preventing gastric cancer.

PATIENTS AND METHODS

 For the development of the CNN, we used 179 upper gastrointestinal endoscopy images obtained from 139 patients (65 were HP-positive: ≥ 10 U/mL and 74 were HP-negative: < 3 U/mL on HP IgG antibody assessment). Of the 179 images, 149 were used as training images, and the remaining 30 (15 from HP-negative patients and 15 from HP-positive patients) were set aside to be used as test images. The 149 training images were subjected to data augmentation, which yielded 596 images. We used the CNN to create a learning tool that would recognize HP infection and assessed the decision accuracy of the CNN with the 30 test images by calculating the sensitivity, specificity, and area under the receiver operating characteristic (ROC) curve (AUC).

RESULTS

 The sensitivity and specificity of the CNN for the detection of HP infection were 86.7 % and 86.7 %, respectively, and the AUC was 0.956.

CONCLUSIONS

 CNN-aided diagnosis of HP infection seems feasible and is expected to facilitate and improve diagnosis during health check-ups.