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.     

Gastric mucosal plasminogen activators inHelicobacter pylori infection

Long-termH. pylori associated gastritis is recognized as a pathogenic factor in gastric carcinogenesis. In gastric carcinomas the amount and activity of the tissue-type plasminogen activator (t-PA) have been reported to be decreased, whereas those of the urokinase-type plasminogen activator (u-PA) were increased, contributing to the neoplastic and invasive process. The present study was performed to determine t-PA and u-PA levels and activity in gastric mucosa from 102 patients and to investigate whether these levels are influenced byH. pylori infection. The antigen concentration and activity of t-PA and u-PA in corpus mucosa were low (P<0.001) compared with those in antral mucosa, although for the u-PA activity this did not reach statistical significance. InH. pylori-associated antral gastritis the mucosal t-PA antigen concentration and activity were found to be decreased (P<0.001) compared with normal mucosa, whereas inH. pylori-associated pangastritis the corpus t-PA levels were not affected. The antigen concentration and activity of u-PA were found to be significantly (P<0.005) increased, both inH. pylori-associated gastritis of antrum and corpus mucosa. Levels of u-PA in histologically normal corpus mucosa of patients with anH. pylori-associated antral gastritis were also found to be increased (P<0.05). In conclusion, the alterations in the plasminogen activator profile found inH. pylori-associated gastritis, ie, a decrease in t-PA and an increase in u-PA, show a similar tendency as the previously found alterations in gastric carcinomas, which provides additional support for the possible involvement ofH. pylori-associated gastritis in the pathogenesis of gastric carcinoma.     

Helicobacter pylori infection accelerates human gastric mucosal cell proliferation

Helicobacter pylori causes chronic atrophic gastritis and intestinal type gastric cancer arises against a background of atrophic gastritis. Increased proliferation of epithelial cells is an important indicator of increased risk for gastric adenocarcinoma. We investigated gastric mucosal cell proliferation inH. pylori-associated gastritis and the effect of eradication therapy on this proliferation in 45 patients endoscopically diagnosed (31 with persistent eradication and 14 in whomH. pylori) recurred.H. pylori status was determined by culture and histology in biopsied specimens from the gastric antrum and corpus. Eradication of the infection was defined as reversal to negative on both tests. In vitro Ki-67 immunostaining of endoscopic biopsy specimens was used to measure mucosal cell proliferation inH. pylori-associated gastritis before and after therapy. The proliferative zone was defined as the distance of Ki-67-positive gastric epithelial cells between the highest and the lowest cells. In patients in whomH. pylori was eradicated, cell proliferation in both the antral and corpus mucosa had decreased 4 weeks after completion of the eradication therapy (P<0.01,P<0.001), and 6 months later, it had markedly decreased (P<0.05,P<0.05) and returned to normal. In patients in whomH. pylori recurred, only antral epithelial cell proliferation was reduced 4 weeks after eradication therapy, but whenH. pylori recurred, determined by culture and histology, cell proliferation level was the same as that before eradication. These results suggest thatH. pylori infection accelerates cell proliferation in gastric mucosa and may play a causal role in the chain of events leading to gastric carcinoma.     

Gastric epithelial cell turnover and mucosal protection in Japanese children with Helicobacter pylori infection

Background In adults, epithelial cell proliferation and apoptosis of the gastric mucosa are induced by Helicobacter pylori infection and are associated with gastric atrophy or gastric carcinoma. In children, there are few studies about such epithelial changes. To elucidate the role of H. pylori infection in gastric mucosal inflammation, we immunohistochemically examined gastric mucosa of Japanese children.Methods Biopsy specimens obtained from the gastric antrum and corpus of H. pylori-infected (n = 13) and noninfected children (n = 15) were studied for immunolocalization of Ki-67, single-strand DNA, manganese superoxide dismutase (Mn-SOD), and CD68, and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling. In 10 patients with successful eradication, pre- and posttreatment results were compared.Results In both gastric antrum and corpus, neutrophil and mononuclear cell infiltration, epithelial cell proliferation, and apoptosis significantly increased in H. pylori-infected patients, predominantly in the antrum. In the antrum of H. pylori-infected patients, there was positive correlation between the degrees of neutrophil infiltration and cell proliferation (P < 0.05) or apoptosis (P < 0.05). H. pylori eradication improved mucosal inflammation, cell proliferation (P < 0.001), and apoptosis (P < 0.01) in the antrum. Mn-SOD immunoreactivity and CD68-positive macrophages in the antrum, which significantly increased in H. pylori-infected patients, decreased after the eradication.Conclusions H. pylori infection induced gastric mucosal inflammation and epithelial cell turnover in children. Moreover, gastric mucosal defense mechanism against H. pylori infection was activated. H. pylori eradication in childhood might prevent the accumulation of gastric epithelial cell damage.     

Critical role of <Emphasis Type="Italic">Helicobacter pylori</Emphasis> in the pattern of gastritis and carditis in residents of an area with high prevalence of gastric cardia cancer

We have investigated the role of Helicobacter pylori infection and of other risk factors of gastritis and carditis in residents of a high-risk area for gastric cardia cancer. During a national population-based endoscopic survey, 508 randomly-selected participants aged ≥40 were enrolled. Mucosal biopsies were obtained from six standard sites. Polymorphonuclear (PMN) and mononuclear (MN) infiltration and combined inflammatory scores (CIS) for chronic gastritis and H.pylori were assessed. Relationships of H.pylori and reflux esophagitis with these variables were calculated for cardia and non-cardia subsites. Both PMN and MN infiltrations correlated strongly with H.pylori infection. For PMN the relationship was maximum for the antrum (odds ratio (OR) = 9.4 (5.2–17.1)) and minimum for the gastric body (OR = 1.7 (1.0–2.9)). There was a significant relationship between carditis and H.pylori (OR = 2.8 (1.7–4.9)). A similar relationship was obtained for MN infiltration. In 56% of subjects the mean MN score for the corpus was equal to or greater than that for the antrum. For 59% of subjects the MN score for the cardia was greater than or equal to the antral score. Use of logistic regression revealed that was the main risk factor for gastritis and carditis in all sites. There was an inverse relationship between reflux esophagitis and carditis. H.pylori is the main risk factor for gastritis for all sites of the stomach including the cardia; but this relationship is stronger for the antrum and cardia than for the body. Continuous cardia inflammation may contribute to the high incidence of gastric cardia cancer in this region.     

Characterization of the Gastric Cardia in Volunteers from the General Population

The aim of this research was to characterize the mucosa of the gastric cardia in relation to infection with Helicobacter pylori and the occurrence of chronic gastritis in other parts of the stomach in a sample of the general population. In this study, 80 adult volunteers underwent esophagogastroscopy with biopsies from the gastric cardia, corpus, and antrum. Gastritis was classified according to the Sydney system. Chronic gastritis (cardia excepted) was diagnosed in 35 subjects, 30 with H. pylori infection. Epithelial proliferative activity (Ki-67), p53- and p21 expression were examined quantitatively with cell counting after immunohistochemical stainings. Esophagitis was diagnosed macroscopically. Fourty eight subjects had cardia-type and 32 corpus-type mucosa in the anatomical cardia. The prevalence of esophagitis (nine cases) did not differ between these groups. Carditis was more prevalent among subjects with cardia-type mucosa (73 vs. 28%, P < 0.0001). H. pylori was present in 48% of those with cardia-type and 25% of those with corpus-type mucosa (P = 0.06). Of the 44 subjects with carditis, 31 had H. pylori in this location. The group with H. pylori infection had significantly higher mucosal proliferative activity when compared to uninfected subjects. Among the subjects with H. pylori-associated carditis, more p53-positive epithelial cells were detected compared to both the non-infected group (P = 0.0004) and to subjects with non-H. pylori-associated carditis (P = 0.03). In subjects with cardia-type mucosa, and both carditis and gastritis, the degree of chronic inflammation was higher in the cardia compared to the corpus and antrum and the p53 expression was significantly higher in the cardia compared to the corpus, but similar to that in the antrum. The proliferative activity was significantly higher in the antrum compared to the cardia and corpus, respectively. In conclusion, H. pylori infection, carditis, and increased p53 expression are more common in subjects with cardia- than corpus-type mucosa in the gastric cardia. Carditis is mainly related to H. pylori infection. There are some differences regarding inflammation, proliferative activity, and p53 expression between the cardia and other regions of the stomach, yet the significance of these differences remains to be clarified.     

Helicobacter pylori infection induces a reversible expression of the CDX2 transcription factor protein in human gastric epithelium

Objective. The homeobox gene CDX2 is implicated in the appearance of intestinal metaplasia in Helicobacter pylori gastritis. The aim of this study was to investigate whether CDX2 expression in gastric mucosa occurs before the appearance of overt intestinal metaplasia in H. pylori gastritis, and whether or not this expression is reversible. Material and methods. CDX2 was studied by immunohistochemistry in a cohort of 38 patients with H. pylori gastritis before and after eradication (mean follow-up 6.3 years) of H. pylori. A cohort of 49 individuals with healthy stomachs was analysed as a control. Results. In the control group no immunostaining of CDX2 in the epithelial cells of the gastric body was found, while in 57% of the cases a mild, aberrant nuclear immunostaining of CDX2 in the non-metaplastic epithelial cells in antrum, designated as “positive staining of single cells” (PSSC), was found. In H. pylori gastritis, the PSSC was seen in antrum and corpus in 100% and 26% of the cases, respectively. The prevalence of antral PSSC was significantly increased (on average by 4-fold) in H. pylori gastritis as compared with controls. After eradication of H. pylori, the prevalence of PSSC decreased significantly in antrum but not in corpus. Conclusions. Expression of CDX2 at low intensity is common in the epithelium of normal antrum, and this expression is enhanced in H. pylori gastritis. Expression of CDX2 is reversible at least in antrum after eradication of H. pylori infection.     

Nodular gastritis in Japanese young adults: endoscopic and histological observations

Background Endoscopic findings of nodular gastritis (NG) are characterized by the presence of Helicobacter pylori infection and follicular gastritis. A possible association with diffuse-type gastric cancer has recently been suggested from observations in Japanese. Our aim was to analyze antral nodularity and histological scores in young adults. Methods Subjects (55 men and 45 women; age range, 18–25 years) with upper gastrointestinal (GI) symptoms or positive H. pylori antibodies underwent endoscopy. One specimen each was obtained from the greater and lesser curvatures (curves) of the corpus and from those of the antrum. Endoscopic appearance was assessed using 0.2% indigo carmine, and histopathological grading was evaluated by the updated Sydney System. Results Antral nodularity was identified in none of 17 H. pylori-negative subjects and in 55 of 83 (66.3%) H. pylori-positive subjects. By the distribution of nodular or granular elevated lesions in the antrum, NG was divided into diffuse (n = 27) or nondiffuse (n = 28) types. The diffuse-type NG predominantly affected women (odds ratio, 3.9; 95% confidence interval, 1.5–10). The atrophy scores in the lesser curve of the antrum were significantly higher in the nondiffuse than in the diffuse group. However, the scores for activity, inflammation, and H. pylori density were not significantly different among the three groups. Conclusions Diffuse-type NG depended on sex, and antral nodularity seemed to change from the diffuse to the nondiffuse type in association with atrophy.     

Risk of Recurrence of Gastric Ulcer,Chronic Gastritis,and Grade of Helicobacter pylori Colonization: A Long-Term Follow-up Study of 25 Patients

Maaroos H-I, Kekki M, Vorobjova T, Salupere V, Sipponen P. Risk of recurrence of gastric ulcer, chronic gastritis, and grade of Helicobacter pylori colonization. A long-term follow-up study of 25 patients. Scand J Gastroenterol 1994;29:532-536.

Background: We describe here our observations on colonization of the gastric mucosa by Helicobacter pylori in a long-term follow-up of 25 patients with gastric ulcer (GU).

Methods: All patients were followed-up endoscopically for more than 10 years (mean, 16 years) and endoscopically verified to have GU in the angular or corpus area of the stomach. None had received treatment with H₂ blockers or omeprazole or had undergone any maintenance therapy or surgery. On the basis of the endoscopic findings on the activity of GU at follow-up endoscopies, the patients were divided into a group of subjects with 'low risk' of recurrence (15 patients who either had no (7 patients) or only a single recurrence (8 patients) at the first follow-up endoscopy but not thereafter) and into those with a 'high risk' of recurrence (10 patients who had at least 2 episodes of recurrence at follow-up endoscopies).

Results: A severe bilateral (antrum and corpus) colonization of the gastric mucosa by H. pylori at the first re-examination (1-6 years after the initial diagnosis of GU) was the most important characteristic feature in the patients with high risk of recurrence as compared with those with low risk. In the course of the follow-up, colonization of the corpus mucosa by H. pylori remained rather unchanged in both high- and low-risk subjects but decreased in grade in antrum particularly in those with low risk (no bacteria at the last endoscopy in 13 of 16 low-risk patients and in 2 of 8 high-risk patients). In both low-and high-risk groups corpus gastritis developed progressively into atrophic gastritis (11 of 25 patients had severe corpus atrophy at the last endoscopy). On the other hand, antral gastritis showed a tendency to heal (13 of 24 patients had normal or only slightly gastritic antrum at the last endoscopy).

Conclusions: The observations indicate that the H. pylori plays a role in and associates closely with the long-term course of angular or corpus GU disease and is related to the tendency of these ulcers to recur.     

Apoptosis in Different Compartments of Antrum and Corpus Mucosa in Chronic Helicobacter pylori Gastritis. An 18-Year Follow-up Study

Background: The association of apoptosis was analysed in three different compartments (foveolar cells- FC, proliferating zone-PZ and glandular part-GP) of antrum and corpus mucosa specimens with development of atrophy and the extent of apoptosis as depending on grade of chronic inflammation, activity of gastritis and Helicobacter pylori colonization at two time points of an 18-year follow-up in an adult population from Saaremaa, Estonia, with a high prevalence of H. pylori infection were compared. Methods: A total of 68 persons (31 men, 37 women; median age, 39 years in 1979) from a primary sample of 304 subjects, endoscoped in 1979 and reinvestigated by endoscopy and biopsy in 1997, were included in the study. The state of the gastric mucosa and the presence of H. pylori in the antrum and corpus mucosa were assessed in accordance with the Sydney system. The dynamics of apoptotic index (AI) between two time points in 1979 and 1997 was evaluated in antrum biopsies of 49 persons and in corpus biopsies of 64 persons. Apoptosis was measured using terminal deoxyuridine nucleotide nick end labelling (TUNEL) histochemistry. Results: The antrum as well as the corpus of 2/68 persons were H. pylori negative at both time points. Atrophy developed in 9/68 persons in the antrum and in 23/68 in the corpus. In PZ and GP of the corpus mucosa as well as in GP of the antrum mucosa, AI decreased significantly during 18 years compared with initial values (P &lt; 0.05), which was not associated with development of atrophy. In all compartments of the antrum and corpus mucosa, studied at the initial and end points of observation, AI did not reveal a difference in persons with and without development of atrophy (P &gt; 0.05). In the samples of 1979 the highest independent effect on the value of AI in the FC compartment for the antrum was exerted by grade of activity of gastritis (P = 0.01) and in GP by degree of chronic inflammation (P = 0.03), while in the samples of 1997 the highest effect was exerted by grade of H. pylori colonization (P = 0.02 and 0.03 in FC and GP, respectively). For the corpus mucosa AI was most strongly affected also by grade of activity of gastritis in FC compartment (P = 0.02) and by degree of chronic inflammation in PZ (P = 0.04), but not by grade of H. pylori colonization. Conclusion: AI was not associated with development of atrophy, but was largely dependent on grade of activity of gastritis and degree of chronic inflammation; in the antrum mucosa AI depended also on grade of H. pylori colonization.     

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.     

High acid secretion may protect the gastric mucosa from injury caused by ammonia produced by Helicobacter pylori in duodenal ulcer patients

The aim of the present study was to investigate the mechanism by which gastric atrophy does not tend to occur in patients with duodenal ulcer despite frequent Helicobacter pylori infection. This investigation was performed in 60 patients with duodenal ulcer and 63 age-matched gastritis patients. Endoscopic findings in the antrum and corpus were classified as normal, atrophic and superficial changes. Biopsy specimens were taken from the antrum and corpus. Ninety per cent of patients with duodenal ulcer and 63.5% of patients with gastritis had H. pylori infection (P<0.01). The incidence of normal findings in duodenal patients was 30% in antral regions and 50% in the corpus (P<0.05). Atrophic change was observed in 21.7% of patients in the antrum and 3.3% of patients in the corpus (P<0.01). The grade of inflammation in duodenal ulcer specimens was significantly higher in the antrum than in the corpus (P<0.01). >H. pylori density was significantly higher in the antrum than in the corpus in ulcer patients (P<0.01). No significant difference in endoscopic findings, >H. pylori density or the grade of inflammation was found between the antrum and corpus in patients with gastritis. The mean intragastric ammonia concentration was 10.3 mg/dL in duodenal ulcer patients and 6.2 mg/dL in gastritis patients (P<0.01). The mean pH was 3.5 and 4.6 in ulcer and gastritis specimens, respectively (P<0.01). Our data suggest that gastric mucosa injury is less frequently associated with duodenal ulcers than with gastritis due to the low >H. pylori density in the corpus and to the higher acid output that neutralizes the ammonia produced by H. pylori.     

Frequency of Helicobacter pylori and Gastritis in Healthy Subjects without Gastrointestinal Symptoms

To investigate the frequency of Helicobacter pylori and gastritis in asymptomatic adults, 30 healthy volunteers underwent upper endoscopy. Biopsy specimens were obtained from the corporeal and antral mucosa of the stomach. The specimens were examined by light microscopy for gastritis and the occurrence of H. pylori. In 12 subjects signs of gastritis were noted at endoscopy, but only in 7 of them was this diagnosis confirmed histologically. No other abnormalities were observed by the endoscopist. Histologic examination was normal in 17 subjects, but in 13 subjects (43%) inflammation was found in the gastric specimens. Ten had inflammation both in the corpus and in the prepyloric specimens, and in six of these subjects H. pylori was discovered. H. pylori was only found in subjects with inflammation in both the corpus and the antrum. Subjects with gastritis were slightly older than subjects with normal gastric mucosa (median age, 47 versus 37 years; not significant). In the group of subjects with gastritis, persons with H. pylori were older than those without (median age, 53.5 versus 36 years; p = 0.05). The results of our study indicate that gastritis is present before colonization with H. pylori occurs. This could imply that H. pylori is not the cause of gastritis but that the presence of gastritis is a prerequisite for colonization of the bacterium in the stomach.     

Helicobacter pylori Infection Is the Major Risk Factor for Gastric Inflammation in the Cardia

We attempted to clarify the pathogenesis of gastric inflammation in the cardia. Eighty Japanese participated in this study. Biopsy specimens of the gastric antrum, corpus, and cardia (1 cm from the squamocolumnar junction) were obtained, and histological gastritis was evaluated. Cardiac inflammation was also evaluated using magnifying gastroscopy. We examined Helicobacter pylori infection, gastric juice pH/bile acid (BA), serum pepsinogen and gastrin levels, gastroesophageal reflux disease (GERD), and habitual smoking and assessed the relations between these factors and cardiac inflammation. The prevalence of H. pylori infection was statistically higher in patients with cardiac inflammation than in those without inflammation (P < 0.05). The relationship was also demonstrated by magnifying gastroscopy. Cardiac inflammation was linked to low acid output but not linked to the BA concentration or habitual smoking. Cardiac inflammation was more pronounced in patients without GERD. These results suggest that H. pylori is a major risk factor for cardiac inflammation in the Japanese.     

Gastric epithelial proliferation and p53 and p21 expression in a general population sample: relations to age,sex, and mucosal changes associated with H. pylori infection

Helicobacter pylori infection is the main cause of chronic gastritis. The infection has been linked to altered proliferative activity and changes in various cell cycle regulating proteins. To determine, in a general population sample, the proliferative activity and expression of p53 and p21 in males and females of different age groups with and without H. pylori-associated chronic gastritis, gastric biopsies from 273 subjects (188 with and 85 without H. pylori infection) randomly selected from a general population were examined immunohistochemically for Ki-67, p53, and p21. One thousand epithelial cells, including the surface, neck, and glandular areas, were counted in both the corpus and the antrum. Results are expressed as the percentage of positive cells. Subjects with H. pylori infection showed significantly increased proliferative activity and expression of p53 compared to uninfected individuals. Regarding the expression of p21, no difference was detected. Multiple linear regression analysis showed significant associations between chronic inflammation or inflammatory activity, on the one hand, and the degree of proliferation in both the corpus and the antrum, on the other hand. In the antrum, the degree of H. pylori colonization was related to the expression of p53. H. pylori seems to cause increased proliferation and increased expression of p53 (but not p21) in the gastric mucosa, neither of which is age or sex dependent. The proliferative activity is related mainly to events associated with inflammation, while the expression of p53 in the antrum is associated with the degree of H. pylori infection. The action of p53 appears to be independent of p21 activity.     

Helicobacter pylori stimulates inducible nitric oxide synthase in diverse topographical patterns in various gastroduodenal disorders

Overproduction of nitric oxide by inducible nitric oxide synthase (iNOS) acts cytotoxically and contributes to inflammation. We explored the roles of iNOS in the pathogenesis of Helicobacter pylori-associated diseases. Using reverse-transcribed PCR, we examined topographical patterns of iNOS mRNA expression in the gastroduodenal mucosa in H. pylori-negative controls and H. pylori-positive patients with duodenal ulcer (DU), gastric ulcer (GU), and ulcer-free gastritis. iNOS expression showed topographical variations among the tested disorders. As compared to controls, DU had a significantly higher expression of iNOS mRNA in the duodenum, GU in the antrum and duodenum, and gastritis in the antrum and corpus. H. pylori eradication yielded a significant reduction of iNOS mRNA in the duodenum of DU and in the antrum of GU. Diverse topographical patterns of H. pylori-induced iNOS expression may contribute to mechanisms by which H. pylori elicits different clinical disorders.     

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).     

Helicobacter pylori infection and histological changes in siblings of young gastric cancer patients

Background and Aim: Helicobacter pylori infection is a risk factor for gastric cancer. We evaluated whether H. pylori infection and premalignant histological changes are more prevalent in siblings of young gastric cancer patients. Methods: Young (age ≤ 40) gastric cancer patients (n = 185), their young siblings (n = 130), and young control participants (n = 287) were recruited. H. pylori infection and histological changes were assessed using the updated Sydney system in biopsy specimens from three regions. We analyzed the association of H. pylori infection and histological changes with gastric cancer using logistic regression analysis. Results: The H. pylori infection rate was significantly higher in young cancer patients than their siblings (odds ratio [OR] = 2.42, P = 0.001) or control participants (OR = 3.60, P < 0.001). In H. pylori‐infected subjects, corpus gastritis and premalignant changes of the corpus lesser curvature (LCv) were also more prevalent in patients than in siblings or controls. In terms of the antrum, intestinal metaplasia was more prevalent in H. pylori‐infected patients than in siblings or controls, while atrophy was not affected. Siblings also had a higher H. pylori infection rate (OR = 1.60, P = 0.046) and higher prevalence of intestinal metaplasia at the corpus LCv (OR = 2.88, P = 0.027) than control participants. Conclusions: Even in young adults, H. pylori infection is a risk factor for gastric cancer. Young adults with histological findings including corpus predominant gastritis, corpus atrophy, or intestinal metaplasia are at increased risk. Since young siblings share risk factors, screening and treatment should be considered for these family members.     

Does Serum Nitrite Concentration Reflect Gastric Carcinogenesis in Japanese Helicobacter pylori-Infected Patients?

This study investigated whether the serum nitrite concentration reflects Helicobacter pylori-induced inflammation and atrophic changes of gastric mucosa. Ninety-seven patients underwent biopsy of both antrum and fundus. Samples were analyzed by the rapid urease test and histopathological examination according to the updated Sydney system. Fasting serum samples from each subject were analyzed for specific IgG Helicobacter pylori antibodies, pepsinogen I and II concentrations, and NO₂ ^–/NO₃ ^– content. Eleven patients had H. pylori eradicated with proton pump-based triple therapy. There was a strong positive correlation between the Helicobacter pylori density in the gastric mucosa and the serum nitrite concentration, but a negative correlation existed between the atrophic grade of the gastric mucosa and both serum nitrite concentration and Helicobacter pylori density in the gastric mucosa. Serum nitrite concentrations decreased significantly after successful eradication of Helicobacter pylori. Therefore, serum nitrite concentration may be a useful marker for oxidative DNA damage and apoptosis associated with Helicobacter pylori infection.