Elevated risk for gastric adenocarcinoma can be predicted from histomorphology

Mechanistic insights into Jianpi Qinghua Sanyu Yin treatment of raised erosive gastritis: ceRNA-mediated PI3K/AKT signaling pathways

Background

Raised erosive gastritis (REG) is a chronic gastritis with a high risk of malignant transformation. Current treatments often result in high recurrence rates and complications. Jianpi Qinghua Sanyu Yin (JPQHSYY), a traditional Chinese medicine, shows promise in treating REG. However, the underlying molecular mechanisms remain unclear. This study aimed to investigate the potential mechanism of JPQHSYY's therapeutic effects on REG.

Methods

RNA-seq was employed to systematically analyze mRNA, lncRNA, and miRNA profiles in gastric mucosal tissues from REG patients before and after JPQHSYY treatment. The pivotal lncRNA-miRNA and miRNA-mRNA networks were predicted from sequencing data and bioinformatic analysis, and the results were exported using Cytoscape software. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were used for functional exploration. Real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was performed to validate RNA-seq analysis results. CCK8, cell cycle, apoptosis and western blot were performed to detect the effects of miR-122-5p in GES-1 cells in vitro.

Results

RNA-seq analysis revealed 576 differentially expressed lncRNAs (269 upregulated, 307 downregulated), 33 differentially expressed miRNAs (13 upregulated, 20 downregulated), and 1717 differentially expressed mRNAs (777 upregulated, 940 downregulated) in JPQHSYY-treated REG patients. GO and KEGG analyses highlighted key pathways, including the PI3K/AKT signaling pathway, involved in cell cycle and apoptosis regulation. The ceRNA network analysis suggested that JPQHSYY impacts the miRNA-lncRNA interactions. Validation experiments confirmed that JPQHSYY inhibits the PI3K/AKT pathway, reducing cell viability, colony formation, and promoting apoptosis in miR-122-5p transfected GES-1 cells.

Conclusion

The therapeutic efficacy of JPQHSYY in treating REG might be mediated by the ceRNA-driven PI3K/AKT pathway signaling pathways, which is implicated in the proliferation of gastric mucosal epithelial cells. Furthermore, the investigation of miRNA-lncRNA networks could reveal more information on potential new mechanisms and targets for JPQHSYY in the management of REG.

Low Incidence of Synchronous or Metachronous Tumors after Endoscopic Submucosal Dissection for Early Gastric Cancer with Undifferentiated Histology

Background

Gastric cancer with undifferentiated histology has different clinicopathologic characteristics compared to differentiated type gastric cancer. We aimed to compare the risk of synchronous or metachronous tumors after curative resection of early gastric cancer (EGC) via endoscopic submucosal dissection (ESD), according to the histologic differentiation of the primary lesion.

Methods

Clinicopathological data of patients with initial-onset EGC curatively resected via ESD between January 2007 and November 2014 in a single institution were reviewed. We analyzed the incidence of synchronous or metachronous tumors after ESD with special reference to the differentiation status of the primary lesion.

Results

Of 1,560 patients with EGC who underwent curative resection via ESD, 1,447 had differentiated type cancers, and 113 had undifferentiated type cancers. The cumulative incidence of metachronous or synchronous tumor after ESD was higher in the differentiated cancer group than in the undifferentiated cancer group (P = 0.008). Incidence of metachronous or synchronous tumor was 4.8% and 1.2% per person-year in the differentiated and undifferentiated cancer groups, respectively. The Cox proportional hazard model revealed that undifferentiated cancers were associated with a low risk of synchronous or metachronous tumors after adjusting for confounding variables (hazard ratio [95% confidence interval] = 0.287 [0.090–0.918]).

Conclusions

The rate of synchronous or metachronous tumors after curative ESD was significantly lower for undifferentiated cancers compare to differentiated cancers. These findings suggest that ESD should be actively considered as a possible treatment for undifferentiated type EGCs.

The new modified ABCD method for gastric neoplasm screening

BACKGROUND

The ABCD screening method was developed for risk stratification of gastric cancer. It is unclear whether the ABCD method can predict the risk of gastric neoplasms, including gastric adenomas, as observed for gastric cancer. We aimed to devise a modified ABCD method for predicting gastric neoplasms.

METHODS

We reviewed 562 patients who had undergone upper gastrointestinal tract endoscopy and whose serum IgG anti-Helicobacter pylori antibody, gastrin, and pepsinogen (PG) I and PG II data were available. Patients were classified into the following four groups: H. pylori antibody negative and normal PG level (group A), H. pylori antibody positive and normal PG level (group B), H. pylori antibody positive and low PG level (group C), and H. pylori antibody negative and low PG level (group D).

RESULTS

The PG I/PG II ratio was lower in patients with gastric neoplasms than in patients without these lesions (gastric adenoma vs gastric cancer vs no neoplasm, 3.7 ± 2.0 vs 3.8 ± 1.8 vs 4.9 ± 2.1, P < 0.001). The optimal cutoff values of the PG I/PG II ratio for predicting gastric neoplasms were 3.1 for H. pylori antibody negative patients and 4.1 for H. pylori antibody positive patients. A higher group grade was associated with a significantly higher proportion of gastric neoplasms [odds ratio (95 % confidence interval), group A, reference; group B, 1.783 (1.007-3.156); group C, 3.807 (2.382-6.085); and group D, 5.862 (2.427-14.155)].

CONCLUSIONS

The modified ABCD method using two different cutoff values according to the H. pylori antibody status was useful for predicting the presence of gastric neoplasms. This method might be a supplementary screening tool for both gastric adenoma and gastric cancer. However, further studies will be required to provide a definitive conclusion.

Helicobacter pylori Infection Synergistic with IL-1β Gene Polymorphisms Potentially Contributes to the Carcinogenesis of Gastric Cancer

Helicobacter pylori (H. pylori) infection is the most common chronic bacterial infection in the world and the etiological agent for most gastric cancer (GC). Interleukin-1β (IL-1β) is a potent proinflammatory cytokine, and its deregulation is closely associated with the tumorigenesis of several cancers. Recent studies have revealed that the IL-1β-31 and -511T alleles are closely associated with gastric carcinogenesis due to their roles in the induction of gastric precancerous lesions and hypochlorhydria. Furthermore, H. pylori infection has a synergistic effect on the development of GC with IL-1β gene polymorphisms, and the highest prevalence of severe gastric abnormalities are found in patients with both host and bacterial high-risk genotypes (cagA(+)/vacAs1(+)/IL-1β-511T). Therefore, these recent advances demonstrate that H. pylori synergistic with IL-1β gene polymorphisms contribute to the gastric carcinogenesis by their involvement in precancerous gastric lesions and low gastric acid secretion.

Endoscopic quality indicators for esophagogastroduodenoscopy in gastric cancer screening

BACKGROUND

Quality indicators of screening esophagogastroduodenoscopy are essential to improve the detection rate of gastric cancer. However, a reliable, practical indicator of the performance of endoscopists in screening esophagogastroduodenoscopy has not yet been identified.

AIMS

We aimed to identify quality indicators of esophagogastroduodenoscopy for the detection of early gastric neoplasms, including gastric dysplasia and early gastric cancer, focusing on the endoscopic findings.

METHODS

The records of 54,889 individuals who underwent esophagogastroduodenoscopy for gastric cancer screening at the Yonsei University Severance Hospital Health Promotion Center, Seoul, Korea, between February 2006 and July 2013 were analyzed. The detection rates for various gastric lesions including early gastric neoplasms were analyzed for each endoscopist.

RESULTS

Gastric dysplasia, early gastric cancer, and advanced gastric cancer were detected in 97 (0.18 %), 54 (0.10 %), and 21 (0.04 %) of 54,889 individuals, respectively. Multivariate analysis showed that the detection rates of gastric subepithelial lesions and gastric diverticuli were independent factors associated with the detection rate of early gastric neoplasms (regression coefficients of 0.096 and 0.532, respectively). A quality score formula was deduced using these regression coefficients to predict the ability of an endoscopist to detect early gastric neoplasms. A trend test confirmed that the group of endoscopists with a higher quality score showed a significantly higher rate of early gastric neoplasm detection (P < 0.001).

CONCLUSIONS

The detection rates of gastric subepithelial lesions and gastric diverticuli are well correlated with that of early gastric neoplasms. In addition, the proposed quality scoring system could be a good quality indicator for the detection of early gastric neoplasms.

Clinical factors related with helicobacter pylori infection--is there an association with gastric cancer history in first-degree family members?

BACKGROUND

The aim of this study was to assess clinical factors associated with Helicobacter pylori positivity and to evaluate the incidence of gastric carcinoma in first-degree family members of infected patients. A total of 580 patients (mean age:38±17) with gastrointestinal complaints underwent C-14 urea breath test (UBT). Patients were grouped as: Group-1, untreated patients (n:384); and Group-2, patients who previously treated with eradication triple therapy (n:196). C-14 UBT was performed 1-2 months after the completion of eradication therapy. Associations of H pylori positivity with age, gender, ABO and Rhesus groups, smoking, dietary habits, and history of gastric cancer in first-degree family members were evaluated. The frequency of H pylori positivity was significantly higher in group-1 (58%) compared to group-2 (20%), p=0.001. There were no correlations between H pylori positivity and age, gender, ABO groups, Rhesus subgroups, smoking and dietary habits in both patient groups. The frequency of gastric cancer in family members was significantly higher in patients with H pylori infection among group-1, compared to infected patients among group-2 (56% vs. 28.6% respectively, p=0.03). We observed a significant association between H pylori positivity and the presence of gastric cancer in first-degree relatives of group-1 patients. Our results provide some confirmation of the presence of a link between gastric cancer development and H pylori. C-14 UBT is a sensitive, reliable and a widely recommended test for the detection of H pylori infection and recurrence. We suggest that detection and eradication of H pylori may contribute to a reduced risk of gastric cancer in the family members of infected patients.

[Gastric cancer risk estimate in patients with chronic gastritis associated with Helicobacter pylori infection in a clinical setting]

BACKGROUND/AIM

Severity of chronic gastritis associated with Helicobacter pylori infection (CGAHpI) could play a role in evaluating the potential risk to develop gastric cancer. Our aim was to estimate the risk for gastric cancer in a clinical setting, according to histopathologic criteria, by applying the gastric cancer risk index (GCRI) METHODS: Histopathologic study of the gastric biopsies (corpus-antrum) from consecutive adult patients that underwent gastroesophageal duodenoscopy was carried out, and the GCRI was applied in patients presenting with CGAHpI.

RESULTS

One hundred eleven patients (77% female) with a mean age of 38.6±13.1 years were included. Active Helicobacter pylori infection (aHpi) was diagnosed in 77 cases (69.40%). In 45% of the cases with aHpi, pangastritis (23%) or corpus-predominant gastritis (22%) was diagnosed. Nine cases were diagnosed with intestinal metaplasia (8%), 7 of which (77.70%) were in the aHpi group. Twenty one percent of the patients with aHpi had a GCRI of 2 (18.10%) or 3 (2.50%) points (high risk index), while 79.10% accumulated a GCRI of 0 or 1 points (low risk index). Of the patients with no aHpi, none of them had 3 points (p=0.001). Of the 18 patients that accumulated 2 or 3 points, 6 (33.30%) presented with intestinal metaplasia (all with pangastritis and corpus-predominant gastritis), of which 4 cases (66.60%) had aHpi.

CONCLUSIONS

The estimated gastric cancer risk in patients with CGAHpI in the clinical setting studied was relatively low and 5% of the patients had a histopathologic phenotype associated with an elevated risk for developing gastric cancer.

Magnifying endoscopy with narrow-band imaging helps determine the management of gastric adenomas

BACKGROUND

There are no clear clinical criteria for the management of gastric lesions diagnosed as adenomas (Vienna classification category 3) by pre-treatment biopsy. In the present study, we examined the feasibility of magnifying endoscopy with narrow-band imaging (ME-NBI) in discriminating early gastric cancers (Vienna classification category 4 or 5) from adenomas in lesions diagnosed as adenomas by pre-treatment biopsy.

METHODS

This was a single-center cross-sectional retrospective study at a tertiary referral center. One hundred thirty-seven consecutive cases of gastric lesions diagnosed as adenomas in pre-treatment forceps biopsy were examined with conventional non-magnifying endoscopy under white light, non-magnifying chromoendoscopy, and ME-NBI. We investigated the association between the final pathological diagnoses (carcinoma or adenoma) and the following factors: lesion size (mm), color (red or white), macroscopic type (depressed or others), presence of ulceration, and positive ME-NBI finding. The presence of an irregular microvascular pattern or an irregular microsurface pattern with a demarcation line between the lesion and the surrounding area was regarded as a positive ME-NBI finding.

RESULTS

Lesion size was significantly larger in carcinomas than adenomas (P = 0.005). Depressed lesion (P = 0.011), red color (P < 0.001), and positive ME-NBI finding (P < 0.001) were significant predictive factors for carcinoma. Multivariate logistic regression confirmed that red color (odds ratio [OR] 3.04, 95% confidence interval [CI] 1.26-7.34, P = 0.14) and a positive ME-NBI finding (OR 13.68, 95% CI 5.69-32.88, P < 0.001) were independent predictive factors for carcinomas. A positive ME-NBI finding was the strongest predictive factor.

CONCLUSIONS

ME-NBI is useful in planning the management of lesions diagnosed as adenomas by pre-treatment forceps biopsy.

Association of NOD1 and NOD2 genes polymorphisms with Helicobacter pylori related gastric cancer in a Chinese population

AIM: To investigate the association between the tag single nucleotide polymorphisms (TagSNPs) of NOD1 and NOD2 and the risk of developing gastric cancer.

METHODS: We conducted a hospital-based case-control study including 296 incident gastric cancer patients and 160 gastritis controls. Eight TagSNPs in the NOD1 and NOD2 genes were selected from the Hapmap database using the haploview software and genotyped by the Sequenom MassArray system. The serum levels of anti-Helicobacter pylori (H. pylori) IgG were measured by enzyme-linked immunosorbent assay to indicate H. pylori infection. The odds ratios (OR) and 95% confidence intervals (CI) were calculated by unconditional logistic regression, including sex and age as confounding factors.

RESULTS: The NOD1 rs2907749 GG genotype showed a decreased risk for gastric cancer (OR 0.50, 95% CI: 0.26-0.95, P = 0.04) while the rs7789045 TT genotype showed an increased risk (OR 2.14, 95% CI: 1.20-3.82, P = 0.01). An elevated susceptibility to gastric cancer was observed in the subjects with H. pylori infection and the NaOD1 rs7789045 TT genotype (OR 2.05, 95% CI: 1.07-3.94, P = 0.03) or the NOD2 rs7205423 GC genotype (OR 2.52, 95% CI: 1.05-6.04, P = 0.04). Haplotype analysis suggested that the distribution of AGT (rs2907749, rs2075820 and rs7789045) in NOD1 between the cases and control groups was significantly different (P corrected: 0.04), and the diplotype AGT/AGT was associated with an elevated gastric cancer risk (OR 1.98, 95% CI: 1.04-3.79, P = 0.04). The association of the NOD1 rs7789045 TT genotype and the diplotype AGT/AGT was significant with H. pylori-related diffuse-type gastric cancer (OR 3.00, 95% CI: 1.38-6.53, P = 0.01; OR 4.02, 95% CI: 1.61-10.05, P < 0.01, respectively).

CONCLUSION: Genetic polymorphisms in NOD1 and NOD2 may interact with H. pylori infection and may play important roles in promoting the development of gastric cancer in the Chinese population.

Predictive factors for improvement of atrophic gastritis and intestinal metaplasia after Helicobacter pylori eradication: a three-year follow-up study in Korea

BACKGROUND AND AIMS

To date, data on the effects of anti-Helicobacter therapy on the improvement of atrophic gastritis (AG) and intestinal metaplasia (IM) have been conflicting. This study was performed to investigate whether eradication of H. pylori could lead to the improvement of AG and IM, and the prognostic factors associated with the improvement of AG and IM.

METHODS

Four hundred patients consisting of H. pylori-negative (n = 116) and H. pylori-positive (n = 284) groups were followed up 1 and 3 years after initial H. pylori tests. Serum levels of pepsinogen (PG), bacteria, environmental factors, and genetic polymorphisms were determined.

RESULTS

The grade of corpus atrophy decreased at 1 and 3 years after successful eradication (p < .001 and p = .033, respectively). However, there was no significant change in the IM in the antrum and in the corpus. Prediction factors for the improvement of corpus AG by H. pylori eradication were baseline low PG I/II ratio (≤3), high salt intake, and corpus-predominant gastritis. IM improvement was also associated with spicy food intake and high baseline grade of IM, in addition to these factors. In addition, IL-1B-511 C/T and IL-6-572 C/G alleles were found to inhibit IM improvement. However, H. pylori-negative and noneradicated group did not show any significant change in AG or IM.

CONCLUSION

Corpus AG was reversed by H. pylori eradication, and improvement of IM by H. pylori eradiation was more definite in patients with severe IM, low PG I/II ratio, and corpus-predominant gastritis, suggesting that H. pylori eradication is valuable even in severe cases.

Prevalence of Helicobacter pylori genotypes (vacA, cagA, cagE and virB11) in gastric cancer in Brazilian's patients: an association with histopathological parameters

PURPOSE

To investigate the frequency and the association of vacA alleles, cagA, cagE and virB11 genes of Helicobacter pylori from patients with gastric cancer, considering the clinic histopathological parameters.

METHODS

One hundred and one gastric adenocarcinoma tissues were assessed by PCR to detect H. pylori and vacA alleles, cagA, cagE and virB11.

RESULTS

The distribution of cases according to the presence of the genes studied showed that the group containing vacA s1m1, cagA, cagE and virB11 H. pylori genes was significantly more frequent, followed by the group with at least one marker on the right side and left of the island. They were also present in the early stages and were the most frequent in nearly all histopathological grades.

CONCLUSIONS

This study verified that vacAs1m1 and cag-PAI genes, cagA, cagE and virB11 are important H. pylori markers for gastric cancer development. Also, this study corroborates the importance of cagE and cagA together as cag-PAI marker.

Gastric phenotype in children with Helicobacter pylori infection undergoing upper endoscopy

INTRODUCTION

Helicobacter pylori is a definite risk factor for the development of gastric cancer, especially in the context of corpus-predominant gastritis. The infection is usually acquired in early childhood, implying lifelong exposure to this carcinogen if untreated. Our objective was to analyze the prevalence of H. pylori induced corpus-predominant gastritis in children.

MATERIAL AND METHODS

We analyzed the results of 265 esophagogastroduodenoscopies (EGD) in children performed between February 2006 and August 2008; 34 endoscopies were excluded (24 with follow-up investigations, 5 with incomplete data, 5 adults). H. pylori gastritis was defined by the presence of H. pylori in histology or by a positive rapid urease test. Grade of inflammation was rated according to the updated Sydney Scoring System. Gastritis was classified as corpus-predominant when the degree of chronic inflammation was higher in the corpus than in the antrum and vice versa for antrum-predominant gastritis.

RESULTS

Two hundred thirty-one patients (128 female; mean age ± SEM: 10.5 ± 3.5 years) were analyzed. Eighty-four (36%) were H. pylori positive, 147 (64%) patients were negative for H. pylori. In H. pylori positive patients, 39 (46%) patients had pangastritis (one patient with mucosal atrophy, which is regarded as precancerous lesion), 42 (50%) had antrum-predominant gastritis and 3 (4%) had corpus-predominant gastritis. One female patient (15.6 years old) with severe (grade 3) pangastritis had focal mucosal atrophy in both antrum and corpus, but no patient had intestinal metaplasia.

CONCLUSIONS

Corpus-predominant gastritis develops in H. pylori infected children, while mucosal atrophy and intestinal metaplasia develop later in the course of the infection.

Association between peroxisome proliferator-activated receptor-γ gene polymorphism (Pro12Ala) and Helicobacter pylori infection in gastric carcinogenesis

OBJECTIVE

Helicobacter pylori infection is accompanied by inflammatory processes leading to peptic ulcer and gastric cancer in the minority of infected individuals. The interaction between H. pylori virulence factors, host defense mechanisms and environmental factors determine the outcome of clinical manifestations. One of the host factors involved in the processes of inflammation and carcinogenesis is the peroxisome proliferator-activated receptor-γ (PPAR-γ) molecule. The present case-control study aimed to determine polymorphism of PPAR-γ gene and its association with H. pylori infection and gastrointestinal diseases (peptic ulcer and non-cardia gastric cancer) in Iranian patients.

MATERIALS AND METHODS

One hundred and fifty-five patients with upper gastrointestinal diseases (76 peptic ulcer and 79 non-cardia gastric cancer) and 152 matched controls were genotyped for PPAR-γ gene polymorphism (Pro12Ala) by the PCR-RFLP method. Infection with H. pylori was confirmed by histology, the rapid urease test (RUT) and ELISA assay (IgG anti-H. pylori).

RESULTS

The frequency of PPAR-γ G (Ala 12) allele was significantly higher in H. pylori positive patients with non-cardia gastric cancer than in controls (22.8% vs. 3.9%, p = 0.027; OR = 3.28; 95% CI = 1.21-8.89), But there was no significant difference without infection (p = 0.7). Moreover, the PPAR-γ polymorphism was not associated with peptic ulcer in the presence or absence of H. pylori infection.

CONCLUSION

Our results indicated PPAR-γ G allele may be an important contributor to non-cardia gastric cancer in Iranian H. pylori infected patients.

Genetic instability in gastric epithelial neoplasias categorized by the revised vienna classification

BACKGROUND/AIMS

The aim of this study was to determine the structural chromosomal aberrations, such as loss of heterozygosity (LOH) and microsatellite instability (MSI), at multiple tumor suppressor gene loci in gastric epithelial neoplasia categorized by the revised Vienna classification.

METHODS

All tissue samples were excised by endoscopic mucosal resection. Sixty category 3 (low-grade adenoma) tissue samples and 51 category 4 samples (high-grade adenoma and intramucosal carcinoma with adenoma) were examined at the 7 sets of microsatellite loci linked to the tumor suppressor gene locus.

RESULTS

For category 3 and 4 tissue samples, there were no differences in the frequencies of LOH-positive chromosomes or the extent of chromosomal loss. The Helicobacter-pylori (H. pylori)-positive rate was significantly higher in MSI-positive category 4 samples than in category 3 samples (p=0.04). The frequency of MSI positivity was significantly higher in category 4 samples than in category 3 samples (p=0.003).

CONCLUSIONS

H. pylori infection is associated with genetic instability of the premalignant lesion. MSI occurs in the early stages of gastric carcinogenesis and its occurrence increases during malignant transformation. Detection of MSI in premalignant gastric lesions may be a surveillant of risk of malignant transformation.

Overexpression of p73 as a tissue marker for high-risk gastritis

PURPOSE

Histologic assessment of high-risk gastritis for the development of gastric cancer is not well defined. The identification of tissue markers together with the integration of histologic features will be required for this assessment.

EXPERIMENTAL DESIGN

Matched tumor/nontumor adjacent mucosa (NTAM) of 91 early gastric cancer and 148 chronic gastritis cases were evaluated for histologic characteristics (atrophy, intestinal metaplasia, chronic inflammation, polymorphonuclear infiltration, and Helicobacter pylori) by the Sydney System. Atrophy risk assessment was also evaluated by the Operative Link on Gastritis Assessment (OLGA) staging system. Eight tissue markers (BRCA1, HSP90, STAT1, FHIT, EGFR, p73, p53, p16INK4a) and EBV were also evaluated by tissue microarray/immunohistochemistry/in situ hybridization platform. Data were analyzed by contingency tables (2 x 2) using Fisher's exact two-tailed test (P < 0.001) and integrated by Significance Analysis of Microarrays (SAM) and clustering analysis.

RESULTS

Histologically, NTAM have severe intestinal metaplasia/chronic inflammation and severe atrophy assessed by Sydney and OLGA staging systems. H. pylori infection was similar in both groups, and EBV was found only in 5.5% of the tumor samples. Overexpression of p73 was higher in NTAM (50.5%) than in chronic gastritis (10.8%; P < 0.0001). Integration of histologic features and tissue markers showed that overexpression of p73, severe atrophy, and OLGA stage 4 were the most relevant features in NTAM. Clustering analysis correctly assigned NTAM and control cases (P < 0.0001).

CONCLUSIONS

Overexpression of p73 should be considered for the assessment of high-risk chronic gastritis. SAM allows the integration of histology and tissue markers for this assessment.

Risk factors in malignant transformation of gastric epithelial neoplasia categorized by the revised Vienna classification: endoscopic, pathological, and immunophenotypic features

BACKGROUND

According to the revised Vienna classification, the surgical removal of gastric epithelial neoplasia category 3 (low-grade dysplasia) lesions is not necessary, whereas the removal of category 4 lesions (high-grade dysplasia and intramucosal cancer) is obligatory. However, approximately 15%-30% of low-grade adenomas/dysplasia progress to high-grade lesions or adenocarcinoma, and it is difficult to determine which lesions will advance to true malignancy. The aim of this study was to evaluate the endoscopic, pathological, and immunophenotypic differences between category 3 and 4 lesions according to the revised Vienna classification.

METHODS

All tissue samples were excised by endoscopic mucosal resection. Fifty-two category 3 tissue samples and 54 category 4 samples were evaluated by endoscopic findings; by pathology examination of the surrounding mucosa; and by CD10, MUC2, MUC5AC, MUC6, and RUNX3 immunohistochemical staining.

RESULTS

Univariate analysis showed that the size of the lesion, color change, ulceration, gastritis score of the surrounding mucosa, and positive expression of MUC6 were associated with category 4 lesions. Multivariate analysis showed that the size of the lesion, ulceration, and positive expression of MUC6 were strongly associated with category 4 lesions.

CONCLUSION

Lesions more than 17 mm in diameter or lesions that are associated with ulceration have the potential for malignant transformation. Positive immunoreactivity for MUC6 appears to be a complementary marker for malignant transformation of gastric epithelial neoplasia.

The usefulness of magnifying endoscopy with narrow-band imaging to distinguish carcinoma in flat elevated lesions in the stomach diagnosed as adenoma by using biopsy samples

BACKGROUND

Therapeutic strategies for flat elevated (0-IIa) lesions in the stomach diagnosed as adenoma by biopsy are currently not established, because some difficulties have previously been reported in the evaluation of vascular patterns alone for the differential diagnosis between adenoma and carcinoma.

OBJECTIVE

We attempted to evaluate the 0-IIa lesions diagnosed as adenoma by using magnifying endoscopy with narrow-band imaging (MENBI) to distinguish them as either adenoma or carcinoma.

SETTING

Department of Gastroenterology, Fujita Health University.

PATIENTS

Fourteen adenomatous lesions (6 adenomas and 8 carcinomas confirmed postoperatively) diagnosed with preoperative biopsies from patients who had undergone endoscopic submucosal dissection were evaluated.

INTERVENTIONS

We selected 5 sites per lesion for MENBI. Selected sites were divided into superficial structures (SSs) and irregular microvascular patterns (IMVPs).

MAIN OUTCOME MEASUREMENTS

The rate of SSs and IMVPs in adenoma and carcinoma.

RESULTS

Significant SSs were tubular in the adenoma and unclear in the carcinoma. Regarding IMVP subcategories, (1) slight intrastructual irregular microvascular patterns (ISIMVPs) accounted for 97%, (2) severe ISIMVPs accounted for 0%, (3) fine networks accounted for 3%, and (4) corkscrews accounted for 0% of cases in the adenomas. The corresponding proportions in the carcinomas were (1) 40%, (2) 15%, (3) 45%, and (4) 0%. Severe ISIMVPs and fine networks were significant findings for carcinomas.

LIMITATIONS

The number of cases was limited.

CONCLUSIONS

Our combined evaluation method using MENBI offers the ability to establish proper therapeutic strategies for lesions that are difficult to identify as adenoma or carcinoma.

Association of Helicobacter pylori restriction endonuclease-replacing gene, hrgA with overt gastrointestinal diseases

BACKGROUND AND AIM

Helicobacter pylori has been proven to be responsible for causing various gastrointestinal disorders including gastric adenocarcinoma. Several genes of pathogen (the genes of the cag-PAI, vacA, iceA, and babA) either in combination or independently have been reported to significantly increase the risk of ulceration/gastric carcinoma, with the cagA gene having the strongest predictive value. Pursuit to identify new genes which could serve as a marker of overt disease progression, lead to the discovery of hrgA gene.

METHODS

Fifty-six indigenous strains of H. pylori from subjects with various gastric disorder were screened to assess the status of hrgA gene along with the cagA gene using simple polymerase chain reaction using specific oligonucleotide primers. Post-amplification, amplicons were subjected for sequencing to identify any strain specific variations in sequences from the H. pylori isolated from different disease manifestations. Histopathological analysis was done to ascertain any significant change in the histological scores of subjects infected with cagA+/hrgA+ and cagA-/hrg+ strains.

RESULTS

All the 56 (100%) subjects amplified with the oligonucleotide primers specific to hrgA gene, whereas 81.71% subjects showed the presence of cagA gene. Sequencing of the amplimers showed 99% homology. Histology of the cagA+/hrgA+ and cagA-/hrg+ subjects did not show any significant difference.

CONCLUSION

hrgA gene of Helicobacter pylori is not a ideal surrogate marker for identifying individuals with higher risk of developing overt gastro-duodenal diseases such as neoplasia of the stomach.

Change of Smad4 expression in gastric carcinogenesis and its clinicopathological significance

AIM: To characterize the changes of Smad4 expression in the multistage carcinogenesis of gastric cancer and investigate the correlations between these changes and the clinicopatholo-gical features.

METHODS: The expression of Smad4 was detected by immunohistochemisty in the paraffin-embedded samples from 103 patients with gastric carcinoma (16 cases in early stage, 87 cases in progressive stage). The result was comparatively analyzed with the histopathology.

RESULTS: Among 103 gastric carcinoma samples, 28 cases with intestinal metaplasia and 13 cases with atypical hyperplasia were determined. In 2 cases, intestinal metaplasia and atypical hyperplasia were simultaneously determined in the same tissue. Normal gastric mucosa showed positive Smad4 expression. Smad4 expression decreased in different degrees of lesions, and the reduced rate increased with the lesion progression (P < 0.05). The positive rates of Smad4 expression in intestinal metaplasia and atypical hyperplasia were 89.3% and 76.9% respectively, while it was 54.4% in carcinoma cells. Positive expression of Smad4 was found in 10 (62.5%) of early carcinoma and 46 (52.9%) of advanced one. The expression of Smad4 in gastric carcinoma showed a significant correlation with the differentiation of carcinoma (P < 0.01). The reduced rate of Smad4 expression in poorly-differentiated carcinoma was higher than that in well-differentiated one (63.0% vs 31.6%, P < 0.01). Positive expression of Smad4 was found in 15 of 20 gastric cardia carcinoma (75%), which was significantly higher than that in the other positional carcinoma (P < 0.05). The positive rates of Smad4 expression in gastric carcinoma of fundus, corpus and antrum were 50%, 53.6% and 46.7% respectively. Smad4 expression had no marked correlations with the age of patients, gender, tumor size, lymph node metastasis and the depth of tumor invasion (P > 0.05).

CONCLUSION: Reduced expression of Smad4 is a frequent molecular event in gastric carcinogenesis, and closely correlated with the progression of lesions and differentiation of carcinoma.