Epithelial cell turnover in relation to ongoing damage of the gastric mucosa in patients with early gastric cancer: increase of cell proliferation in paramalignant lesions

Background Gastric cancer is typically an end result of Helicobacter pylori-associated chronic gastritis. The pathogenesis is thought to involve effects on gastric mucosal epithelial cell turnover. In this study, we aimed to compare apoptosis and proliferation in the noncancer-containing mucosa of H. pylori-positive patients with early gastric cancer with these phenomena in H. pylori-positive controls.Methods Two specimens each were obtained from the greater and lesser curvatures of the corpus and from the greater curvature of the antrum. The histopathological grading used was the updated Sydney System. Apoptotic epithelial cells were detected using the terminal deoxy nucleotidyl transferase-mediated deoxy-uridine triphosphate (dUTP) biotin nick-end labeling (TUNEL) method. The expression of Ki 67 was evaluated by immunostaining.Results Forty-five H. pylori-positive patients with endoscopic mucosal resection for early gastric cancer and 52 H. pylori-positive controls were studied. Gastric cancer was associated with a higher frequency of incomplete intestinal metaplasia (IM; odds ratio [OR], 19.1; 95% confidence interval [CI], 6.9–53.2; P < 0.001). The apoptotic index (AI) in the greater curvature of the corpus and the proliferation index (PI) in each part were significantly higher in cancer patients than in the control group. The median PI in the antrum was significantly higher in the incomplete IM group than that in the complete IM group (17.6 vs 12.6; P = 0.009). The PI and the AI in the greater curvature of the corpus correlated with the activity score, and the PI correlated with the IM score.Conclusions In the cancer patients, H. pylori-induced gastritis was associated with increased cell proliferation and apoptosis compared with mucosal findings in the controls. IM seems to be one of the most important factors affecting cell proliferation and may be one of the components of carcinogenesis that results in proliferation-dominant cell kinetics.     

Histological characteristics of gastric mucosa prior to Helicobacter pylori eradication may predict gastric cancer

Abstract

Objective. Although Helicobacter pylori (H. pylori) eradication has been shown to inhibit gastric cancer, it does not completely suppress it. Therefore, risk factors of gastric cancer development following H. pylori eradication were examined. Material and methods. A total of 2355 patients (1501 males and 824 females) underwent successful eradication of H. pylori. Endoscopic atrophy, histological gastritis, atrophy, intestinal metaplasia (IM), and operative link for gastritis assessment (OLGA) staging were subsequently evaluated. Results. Following eradication, 33/2355 patients (25 males and 8 females) developed gastric cancer. Compared to a nongastric cancer group that was matched according to gender and age, the incidence of endoscopic atrophy (3.52 ± 1.45 vs. 4.85 ± 1.18, p < 0.001), histological atrophy at the greater curvature of the antrum (1.42 ± 0.80 vs. 1.95 ± 0.86, p = 0.0059), inflammation (2.05 ± 0.59 vs. 2.33 ± 0.66, p = 0.031), IM at the greater curvature of the corpus (0.06 ± 0.30 vs. 0.24 ± 0.54, p = 0.029), the ratio of OLGA-stage 0–II/III, IV (13/8 vs. 55/11, p = 0.038) were significantly higher for the gastric cancer group. Multivariate analysis also showed the highest odds ratio (6.26, 95% confidence interval or CI, 1.28–30.60, p = 0.023) for IM at the greater curvature of the corpus. Conclusions. Severe endoscopical atrophy, OLGA staging, histological atrophy at the antrum, inflammation, and particularly IM at the corpus, were identified as risk factors for gastric cancer development following H. pylori eradication. Therefore, eradication should be performed before these predictors develop.     

Helicobacter pylori in promotion of gastric carcinogenesis

Gastric atrophy and intestinal metaplasia are considered the earliest phenotypic changes in the cascade of events leading from normal mucosa to intestinal-type gastric cancer, and epidemiological evidence linksHelicobacter pylori to gastric epithelial malignancies. To evaluate any causal relationship between bacterial infection and atrophic metaplastic lesions, gastric pathology was histologically and histochemically evaluated in 267 consecutive, nonulcerous, untreated subjects, with attention given to the phenotypes of intestinal metaplasia. The prevalence ofHelicobacter pylori infection was 61%. Intestinal metaplasia (particularly types II and III) was significantly associated with bothHelicobacter pylori detection (x _LR ² :P<0.002) and increasing age (x _LR ² :P<0.002). Using logistic regression analysis, the development of intestinal metaplasia proved more significantly linked withHelicobacter pylori infection [odds ratio=4.55 (95% confidence interval: 1.51–13.7)], than with age [odds ratio =1.03 (95% CI: 1.01–1.06)], with no interaction. In conclusion,Helicobacter pylori can be considered among the major causal agents of mucosal lesions involved in the multistep process of gastric carcinogenesis, justifying any attempt to eradicate this bacterial infection.     

Atrophy–metaplasia–dysplasia–carcinoma sequence in the stomach: a reality or merely an hypothesis?

The results of recent investigations have suggested that the old hypothesis of an atrophy–metaplasia–dysplasia–carcinoma sequence in the stomach needs to be qualified. The most common cause of intestinal metaplasia is Helicobacter pylori gastritis. The consequence of this intestinal metaplasia is focal atrophy.Helicobacter pylori infection may also trigger an autoimmune gastritis of the corpus mucosa, with atrophy and intestinal metaplasia. Most intestinal metaplasias are only ‘paracancerous’ but not ‘precancerous’ lesions. Diffuse gastric carcinomas, such as the signet ring cell carcinoma, arise independently of intestinal metaplasia. Histogenetically, numerous carcinomas of the stomach are primarily of the gastric type, and may secondarily change into the intestinal type.High-grade intra-epithelial neoplasias (dysplasias) detected during the biopsy-based diagnostic work-up appear to be a marker for carcinoma and must, therefore, be removed endoscopically.The detection of intestinal metaplasia in routinely obtained biopsy material is subject to sampling error and is, therefore, not a suitable marker for an increased risk of a gastric carcinoma developing. As an alternative, the concept of gastritis of the carcinoma phenotype, which is more frequently found in early gastric carcinomas and in the relatives of gastric carcinoma patients, has been developed. In this concept, the diffuse parameters of grade and activity of the gastritis in the antrum and corpus, which are independent of sampling error, are subjected to a comparative analysis. A risk gastritis of the carcinoma phenotype is diagnosed when the grade and activity of the gastritis in the corpus are at least equally as pronounced as in the antrum. Currently, this concept is being tested in a prospective ongoing study. Future studies must show whether, and if so which, immunohistochemical or molecular-genetically detectable changes can be applied as risk markers in the diagnostic work-up.Helicobacter pylori eradication probably does not lead to complete regression of the intestinal metaplasia and ensuing focal atrophy. However, eradication ofH. pylori does lead to the normalization of changes that can lead to mutations of the stem cells of the gastric mucosa (free radicals, nitric oxide, cell proliferation and vitamin C secretion).     

Role of intestinal metaplasia subtyping in the risk of gastric cancer in Korea

Background and Aim:  Gastric cancer is believed to develop by a multistage process. Intestinal metaplasia (IM) is regarded as a premalignant condition; it is classified into subtypes I, II and III. The aim of this study was to evaluate whether the subtypes of IM were associated with progression to gastric cancer.
Methods:  The study cohort consisted of 861 subjects, categorized as controls, gastric ulcers, dysplasia and cancer. The IM was scored histologically using the Sydney classification for the antrum and the body of the stomach. The biopsies were stained with high iron diamine and alcian blue (pH 2.5) (HID-AB2.5), and the IM was subtyped as I, II or III.
Results:  The proportion of IM subtypes I, II and III were 14.5%, 47.2% and 38.3% in the antrum, and 28.1%, 57.8% and 14.1% in the body of the stomach, respectively. These distributions did not show significant differences depending on disease or Helicobacter pylori positivity. In cases that were H. pylori -positive, the prevalence of IM subtype II in the cancer and dysplasia groups was higher than in the control group in the body of the stomach ( P  < 0.05). The proportion of IM subtype III in the antrum increased in proportion with age ( P  = 0.036).
Conclusions:  IM subtyping was not found to play a major role in the prediction of gastric cancer development in Korea. IM subtype III was associated with aging, and IM subtype II appeared to be related to gastric carcinogenesis in the presence of H. pylori infection.     

Advanced gastric cancer associated with nodular gastritis in a young patient

A 20-year-old female underwent an endoscopy for epigastralgia that revealed many small, elevated nodules in the antrum that were diagnosed as nodular gastritis. The endoscopy also showed an ulcerative lesion with an uneven round wall at the greater curvature of the middle corpus. Biopsy of the ulcerative lesion yielded a diagnosis of poorly differentiated adenocarcinoma. A distal gastrectomy was performed on the basis of a diagnosis of gastric cancer associated with nodular gastritis. The intraoperative findings revealed serosal invasion of the gastric cancer and the patient tested positive for peritoneal cytology. The pathological findings revealed poorly differentiated adenocarcinoma showing invasive growth with fibrosis on the corpus and large and superficial lymphoid follicles on the miliary nodules at the antrum. The patient was positive for Helicobacter pylori infection by both the serum Helicobacter pylori antibody and histopathological findings.     

Association Between Gastric Atrophy and Helicobacter pylori Infection in Japanese Children: A Retrospective Multicenter Study

The purpose of this study was to determine whether Helicobacter pylori infection and mucosal inflammation result in gastric atrophy in Japanese children. A total of 196 patients ages 1–16 years were retrospectively studied: 131 patients were infected with H. pylori and 65 patients were uninfected. Antral (n = 196) and corpus biopsy specimens (n = 70) were investigated based on the Updated Sydney system. In both the antrum and corpus, H. pylori-infected patients showed significantly higher degrees of inflammation and activity of gastritis, compared with noninfected patients. The prevalence of grade 2 or 3 atrophy in the antrum was 10.7% in H. pylori-infected patients and 0% in the noninfected patients (P < .01) and in corpus 4.3% and 0%, respectively (P = .20). The frequency of intestinal metaplasia in the 2 study groups was 4.6% and 4.6% in the antrum and 0% and 4.2% in the corpus, respectively. Among H. pylori-infected patients, the antrum showed significantly higher degrees of H. pylori density, inflammation and activity of gastritis, and atrophy than the corpus. In the antrum, atrophy was significantly correlated with activity, whereas in the corpus, atrophy correlated with H. pylori density, inflammation, and activity. H. pylori-induced gastric inflammation can cause atrophy in Japanese children, predominantly in the antrum. It remains to be determined whether H. pylori-infected children with gastric atrophy are at increased risk for gastric cancer.     

Evaluation of the association between serum anti-Lewis X antibody and inflammatory infiltration into the gastric mucosa infected with Helicobacter pylori

BACKGROUND: Lipopolysaccharides of Helicobacter pylori have an antigenic structure that mimics Lewis X occurring in gastric mucosa. The pathogenic role of antigenic mimicry in Helicobacter pylori-induced gastritis has been of recent interest. AIM: To examine whether this molecular mimicry affects gastric mucosal inflammation in patients infected with Helicobacter pylori. PATIENTS: A total of 59 patients (mean age 58.0 years, 35 males, 24 females) were studied. METHODS: Serum samples were collected to measure IgG antibodies to Helicobacter pylori and Lewis X. Biopsy specimens were obtained from the antrum and corpus for the grading of gastritis. Correlation coefficients between serum Lewis X antibody titre and histological grades of inflammatory infiltration were determined. RESULTS: There was no significant correlation between anti-Lewis X antibody titre and the grade of mononuclear or polymorphonuclear cell infiltration. High titre of anti-Lewis X antibody was seen only in patients who had increased inflammatory infiltration in the corpus. CONCLUSIONS: Serum anti-Lewis X antibody, possibly induced by Helicobacter pylori infection, does not seem to play a major role in gastric mucosal inflammation in patients with Helicobacter pylori infection.     

Study ofHelicobacter pylori colonization of patches of heterotopic gastric mucosa (HGM) at the upper esophagus

Helicobacter pylori (HP), known to cause active chronic gastritis, has primarily been found in gastric-type mucosa. Even in the duodenum, the organism was detected in islands of metaplastic gastric mucosa. HP has also been found in gastric metaplasia of Barrett's esophagus in 15–50%. The aim of our study was to determine: (1) the frequency with which HP is found on histopathological sections of heterotopic gastric mucosa (HGM) patch(es) at the upper esophagus, as compared to that of the stomach proper, and (2) the histopathological significance of infection in the HGM patches. From 63 patients with HGM patches at the upper esophagus, 48 patients were found to have concurrent adequate specimen from the stomach for modified Steiner's stain. In 22 patients (45.8%), pair sections from HGM and stomach were negative for HP. Of 26 patients (54.1%) HP-positive on sections from the antrum and/or body (both in 21 cases) nine patients (18.7%) demonstrated HP in the HGM patches. Whereas focal acute inflammatory changes on the H&E section of HGM was present in six patients, HP was detected in HGM only in one. Chronic inflammatory cell infiltration was detected in all nine HP-positive HGM patches and in 37 of 39 HP-negative patches. A mixed acute and chronic inflammatory cell infiltration was found in five of these 37 patients. Our data demonstrate that HP infection of HGM patches at the upper esophagus is part of the HP gastritis and an independent colonization of HGM patches without gastric infection does not occur. No correlation was found between the presence of acute and chronic inflammatory changes in H&E-stained section and positivity of HP in modified Steiner's section of HGM.This study was presented in part, as poster, at the Digestive Disease Week of the AGA, May 12–18, 1990, in San Antonio, Texas.     

Regression of duodenal gastric metaplasia in Helicobacter pylori positive patients with duodenal ulcer disease

Background. It is unclear whether the extent of duodenal gastric metaplasia is due to Helicobacter pylori and/or acid.Aims. To investigate the role of Helicobacter pylori eradication in the regression of duodenal gastric metaplasia in patients with duodenal ulcer maintained in acid suppression conditions.Methods. Duodenal (anterior, superior, inferior walls of first part of duodenum) and gastric antrum biopsies were obtained from 44 Helicobacter pylori positive duodenal ulcer patients. Helicobacter pylori infection was diagnosed by rapid urease test, histology and ¹³C-Urea Breath Test. Patients were treated with 20 mg omeprazole tid associated with 250 mg clarithromycin and 500 mg amoxycillin four times daily for 10 days and maintained with 20 mg omeprazole daily for 18 weeks. Control endoscopies were performed at 6 and 18 weeks after beginning treatment.Results. Duodenal gastric metaplasia regression was observed in all ( ) patients in whom Helicobacter pylori was eradicated, but in only 3 out of 6 patients in whom eradication was not achieved (p<0.001).Conclusions. The present results suggest that Helicobacter pylori eradication associated with prolonged acid suppression may represent a good therapeutic strategy to achieve duodenal gastric metaplasia regression and highlight the combined role of acid and Helicobacter pylori in the pathogenesis of duodenal gastric metaplasia.     

Implication of anti-parietal cell antibody levels in gastrointestinal diseases,including gastric carcinogenesis

We investigated serum levels of anti-parietal cell antibody (APCA) in relation to various gastric diseases. Subjects were 224 Japanese patients including 58 with gastric cancer. All patients underwent gastroscopy, and APCA was investigated by enzyme-linked immunosorbent assay. Unexpectedly, there was no difference in APCA levels between patients with gastric cancer and those with gastritis. Among H. pylori-positive patients, APCA levels were closely correlated with grades of atrophy when no gastric cancer was present, but no correlation was found when gastric cancer was present. APCA-negative gastric cancer was found mainly in males and was characterized by massive infiltration of neutrophils in the background mucosa. The 24 patients with gastric cancer were APCA-negative and showed low pepsinogen levels. The odds ratio for the incidence of gastric cancer in these patients was 7.90 (95% CI 3.4–18.4). This suggests APCA-negative gastric cancer is the predominant form of gastric cancer in Japan.     

Serum Pepsinogens as a Predicator of the Topography of Intestinal Metaplasia in Patients with Atrophic Gastritis

The importance of atrophic gastritis with intestinal metaplasia is related to the fact that it increases the risk of gastric cancer development. The aim of this study is to evaluate the diagnostic potential of serum pepsinogens in predicting the topography of intestinal metaplasia. Both dye endoscopy and 13C-urea breath test were carried out in 878 subjects. Serum pepsinogen I, pepsinogen II, and IgG antibody to Helicobacter pylori were measured. The overall prevalence of intestinal metaplasia was higher in subjects with lower PG I/II ratios and lower PG I values. Based on ROC curves, a cutoff value for pepsinogen I/II ratio of less than 3.0 would have identified intestinal metaplasia with a sensitivity of 71.7% and a specificity of 66.7% in Helicobacter pylori-positive subjects. It is possible that serum pepsinogens could be used as a screening test for high-risk subjects with intestinal metaplasia.     

Relationship between the diversity of the cagA gene of Helicobacter pylori and gastric cancer in Okinawa, Japan

Background Helicobacter pylori CagA protein is considered to be one of the virulence factors associated with gastric cancer. CagA is injected into gastric epithelial cells, undergoes tyrosine phosphorylation, and binds to Src homology 2 domain-containing protein-tyrosine phosphatase (SHP-2). Two major subtypes of CagA have been observed in the SHP-2-binding site, the Western and East Asian types. The East Asian-type CagA binds to SHP-2 more strongly than the Western-type CagA. The diversity of CagA, which collectively determines the binding affinity of CagA to SHP-2, may be an important variable in determining the clinical outcome of infection by different H. pylori strains. Methods We investigated the relationship between the diversity of CagA and clinical outcome in Okinawa, Japan. A total 24 strains, 13 gastric cancer strains and 11 duodenal ulcer strains, were studied. We sequenced full-length cagA genes and analyzed the phylogenetic relationships between Okinawa isolates and previously characterized Western H. pylori strains. Results All isolates examined were cagA positive. The prevalence of East Asian CagA-positive strains was significantly higher in patients with gastric cancer (84.6%) than in patients with duodenal ulcer (27.3%) (χ-squared = 8.06, P = 0.011). The phylogenetic analysis showed that all gastric cancer strains with East Asian-type CagA were in the East Asian cluster, and that most duodenal ulcer strains were in the Western cluster. Conclusions The origins of H. pylori isolates are different between gastric cancer strains and duodenal ulcer strains, and East Asian CagA-positive H. pylori infection is associated with gastric cancer. The strain diversity observed in Okinawa may affect the difference in the prevalence of disease associated with H. pylori infection in Japan.     

Antibody response to Helicobacter pylori CagA and heat-shock proteins in determining the risk of gastric cancer development

OBJECTIVE: To investigate whether the systemic antibody response to Helicobacter pylori heat shock protein B can be considered, in addition to anti cytotoxin-associated protein [CagA) antibody determination, a further serological marker of increased risk of gastric cancer development. METHODS: A total of 98 Giemsa positive Helicobacter pylori patients (28 with gastric cancer, 30 with duodenal ulcer and 40 with nonulcer dyspepsia) were studied. Serum samples obtained from all patients were tested for IgG antibodies to CagA (116 kDa), VacA [89kDa) and heat skock protein B (54 kDa) antigens of Helicobacter pylori by the Western blot technique. RESULTS: 26/28 patients [(92.9% with gastric carcinoma, 29/30 patients [96.7%) with duodenal ulcer and 30/40 patients (75.0%) with non-ulcer dyspepsia were seropositive for CagA protein. The prevalence of serum IgG antibody to CagA in the cancer patients was not significantly higher than in duodenal ulcer and non-ulcer dyspepsia patients. The prevalence of antibodies to VacA was not significantly different between gastric carcinoma and non-ulcer dyspepsia patients. In contrast the prevalence of systemic antibodies to heat skock protein B was significantly higher in gastric cancer patients (78.6%) than in duodenal ulcer (36.7%, p=0.002) or nonulcer dyspepsia patients (52.5%, p=0.029). CONCLUSIONS: The detection of antibodies to heat shock protein B is proposed as an additional test which, in association with the determination of serum antibodies to CagA, could help in determining the risk of developing severe gastroduodenal disease, and gastric cancer, in particular.