Gastric dysplasia is a neoplastic lesion and a precursor of gastric cancer. The Padova, Vienna, and World Health Organization classifications were developed to overcome the discrepancies between Western and Japanese pathologic diagnoses and to provide a universally accepted classification of gastric epithelial neoplasia. At present, the natural history of gastric dysplasia is unclear. Much evidence suggests that patients with high-grade dysplasia are at high risk of progression to carcinoma or synchronous carcinoma. Therefore, endoscopic resection is required. Although patients with low-grade dysplasia have been reported to be at low risk of progression to carcinoma, due to the marked histologic discrepancies between forceps biopsy and endoscopic specimens, endoscopic resection for this lesion is recommended, particularly in the presence of other risk factors (large size; depressed gross type; surface erythema, unevenness, ulcer, or erosion; and tubulovillous or villous histology). Helicobacter pylori eradication in patients with dysplasia after endoscopic resection appear to reduce the incidence of metachronous lesions.
Anti-Bacterial Agents/therapeutic use ; Biopsy ; Carcinoma in Situ/classification/microbiology/*pathology/*surgery ; Disease Progression ; *Gastrectomy/adverse effects/methods ; Gastric Mucosa/microbiology/*pathology/*surgery ; Gastroscopy ; Helicobacter Infections/drug therapy/microbiology ; Helicobacter pylori/drug effects ; Humans ; Neoplasm Grading ; Precancerous Conditions/classification/microbiology/*pathology/*surgery ; Predictive Value of Tests ; Risk Factors ; Stomach Neoplasms/classification/microbiology/*pathology/*surgery ; Treatment Outcome

BACKGROUND/AIMS: Controversy exists regarding the characteristics of Helicobacter pylori infection-negative gastric cancer (HPIN-GC). The aim of this study was to evaluate clinicopathologic features of HPIN-GC compared to H. pylori infection-positive gastric cancer (HPIP-GC) using a comprehensive analysis that included genetic and environmental factors. METHODS: H. pylori infection status of 705 resectable gastric cancer patients was determined by the rapid urease test, testing for anti-H. pylori antibodies, histologic analysis and culture of gastric cancer tissue samples, and history of H. pylori eradication. HPIN-GC was defined as gastric cancer that was negative for H. pylori infection based on all five methods and that had no evidence of atrophy in histology or serology. RESULTS: The prevalence of HPIN-GC was 4% (28/705). No significant differences with respect to age, sex, smoking, drinking, family history of gastric cancer or obesity were observed between the two groups. HPIN-GC tumors were marginally more likely to involve the cardia (14.3% for HPIN-GC vs 5.3% for HPIP-GC, p=0.068). The Lauren classification, histology, and TNM stage did not differ according to H. pylori infection status. Microsatellite instability was not different between the two groups, but p53 overexpression in HPIN-GC was marginally higher than in HPIP-GC (56.0% for HPIN-GC vs 37.0% for HPIP-GC, p=0.055). CONCLUSIONS: The prevalence of HPIN-GC was extremely low, and its clinicopathologic characteristics were similar to HPIP-GC.
Antibodies, Bacterial/analysis ; Female ; Helicobacter Infections/*complications/epidemiology/microbiology ; *Helicobacter pylori ; Humans ; Male ; Middle Aged ; Prevalence ; Prospective Studies ; Republic of Korea/epidemiology ; Stomach Neoplasms/epidemiology/*microbiology/*pathology/surgery ; Urease/analysis

BACKGROUND/AIMS: Helicobacter pylori cytotoxin-associated gene A (CagA) has been suggested to be involved in the inactivation of Runt-related transcription factor 3 (RUNX3), a known gastric carcinoma tumor suppressor gene. It remains unclear how H. pylori CagA initiates or maintains RUNX3 promoter methylation and inactivates its protein expression in gastric carcinoma. METHODS: RUNX3 promoter methylation status, RUNX3 expression, and H. pylori CagA were investigated in 76 sample pairs of gastric carcinoma tissue. The patients' medical records were reviewed. The association between RUNX3 methylation or loss of RUNX3 expression and clinicopathologic variables according to H. pylori CagA status were investigated. RESULTS: In gastric carcinoma patients with H. pylori CagA-positive infection, RUNX3 methylation did not show association with lymphatic invasion, venous invasion, and TNM stages. However RUNX3 methylation was observed more frequently in poorly differentiated adenocarcinoma and signet ring cell carcinoma (77.8% vs. 20.0%, p=0.023) in early stage. In gastric carcinoma patients with H. pylori CagA-positive infection, loss of RUNX3 expression did not show association with lymphatic invasion, venous invasion, and TNM stages. However loss of RUNX3 expression was observed more frequently in early gastric carcinoma than in advanced gastric carcinoma (84.2% vs. 75.0%, p=0.51), but this difference was not significant. CONCLUSIONS: In gastric carcinoma patients with H. pylori CagA-positive infection, RUNX3 methylation or loss of RUNX3 expression did not show correlation with lymphovascular invasion and TNM stages. In early gastric carcinoma patients with H. pylori CagA-positive infection, RUNX3 methylation was observed more in poorly differentiated adenocarcinoma and signet ring cell carcinoma.
Adult ; Aged ; Aged, 80 and over ; Antigens, Bacterial/*metabolism ; Bacterial Proteins/*metabolism ; Cell Line, Tumor ; Core Binding Factor Alpha 3 Subunit/genetics/*metabolism ; Female ; *Gene Expression Regulation, Neoplastic ; Helicobacter Infections/complications/microbiology ; Helicobacter pylori/isolation & purification/*metabolism ; Humans ; Immunohistochemistry ; Lymphatic Metastasis ; Male ; Methylation ; Middle Aged ; Neoplasm Staging ; Promoter Regions, Genetic ; Retrospective Studies ; Stomach Neoplasms/complications/microbiology/*pathology

OBJECTIVETo investigate the correlation between infection with L-form of Helicobacter pylori (Hp-L) and the expressions of macrophage migration inhibition factor (MIF), matrix metalloproteinase 9 (MMP9), and vascular endothelial growth factor (VEGF) in gastric cancer.

METHODSHp-L was examined in 80 gastric carcinoma and 50 adjacent normal tissues by Gram staining and immunohistochemical staining, and the expressions of MIF, MMP9 and VEGF were detected by immunohistochemical staining; the expression of MIF mRNA was detected by RT-PCR and the expression of MIF, MMP9 and VEGF proteins were detected by Western blotting in 30 fresh gastric cancer tissues and the corresponding adjacent tissues.

RESULTSOf the 80 gastric carcinoma tissues, 57 (71.25%) showed Hp-L positivity detected by both Gram staining and immunohistochemical staining, as compared with a rate of only 14% in the adjacent normal tissues (P<0.05). The gastric carcinoma tissues showed higher expression levels of MIF, MMP9 and VEGF proteins than the corresponding adjacent normal mucosa; the positivity MIF, MMP-9 and VEGF proteins were significantly higher in Hp-L-positive gastric carcinoma than in Hp-L-negative cases (P<0.05). Positive correlations were found between Hp-L positivity and the expressions of MIF, MMP-9 and VEGF (r=0.598, 0.292, 0.341, respectively, P<0.05). The 30 fresh gastric cancer tissues showed also significantly higher MIF mRNA expression and MIF, MMP-9 and VEGF protein expressions than the adjacent tissues (t=3.729, P<0.01). The expressions of MIF and MMP-9 were also related to the clinicopathological factors including lymph node metastasis and depth of invasion (P<0.05).

CONCLUSIONInfection with L-form of Hp-L can be an important factor that contributes to the invasion and metastasis of gastric carcinoma, the mechanism of which involves up-regulated expressions of MIF, MMP-9 and VEGF.

Adult ; Aged ; Aged, 80 and over ; Female ; Helicobacter Infections ; metabolism ; pathology ; Helicobacter pylori ; Humans ; L Forms ; Lymphatic Metastasis ; Macrophage Migration-Inhibitory Factors ; metabolism ; Male ; Matrix Metalloproteinase 9 ; metabolism ; Middle Aged ; Stomach Neoplasms ; metabolism ; microbiology ; pathology ; Vascular Endothelial Growth Factor A ; metabolism

Helicobacter pylori (H. pylori) undergoes decades long colonization of the gastric mucosa of half the population in the world to produce acute and chronic gastritis at the beginning of infection, progressing to more severe disorders, including peptic ulcer disease and gastric cancer. Prolonged carriage of H. pylori is the most crucial factor for the pathogenesis of gastric maladies. Bacterial persistence in the gastric mucosa depends on bacterial factors as well as host factors. Herein, the host and bacterial components responsible for the incipient stages of H. pylori infection are reviewed and discussed. Bacterial adhesion and adaptation is presented to explain the persistence of H. pylori colonization in the gastric mucosa, in which bacterial evasion of host defense systems and genomic diversity are included.
Gastric Mucosa/*microbiology ; Gastritis/*microbiology/pathology ; Helicobacter Infections/*microbiology ; Helicobacter pylori/*physiology ; Humans ; Stomach Neoplasms/pathology

OBJECTIVES: In Fujian Province, China, gastric cancer is one of the leading causes of mortality among all malignant tumors. Nanjing county and Minqing county are located in inland Fujian and have similar general demographics. However, the adjusted mortality rate of gastric cancer in Minqing was found to be much higher than that in Nanjing. We sought to explore factors associated with this increased risk of gastric cancer between the two counties. METHODS: We recruited 231 and 224 residents from Nanjing and Minqing, respectively, and analyzed differences between their dietary habits, Helicobacter pylori infection rates, and concentrations of serum pepsinogen I, pepsinogen II, gastrin-17, and ratio of pepsinogen I:II. RESULTS: Subjects in Minqing had more first-degree relatives who had been diagnosed with upper gastrointestinal tumor, more unhealthy dietary habits, a higher Helicobacter pylori positive rate, and greater proportion of abnormal serum gastrin-17 than those in Nanjing did. CONCLUSIONS: The factors that differed between these two counties might indicate that residents in Minqing have a higher risk for developing gastric cancer than those in Nanjing do.
Adult ; Aged ; China/epidemiology ; Female ; Food Habits ; Gastrins/blood ; Helicobacter Infections/epidemiology/microbiology/pathology ; Helicobacter pylori ; Humans ; Male ; Middle Aged ; Pepsinogen A/blood ; Pepsinogen C/blood ; Risk Factors ; Stomach Neoplasms/*diagnosis

OBJECTIVES: In Fujian Province, China, gastric cancer is one of the leading causes of mortality among all malignant tumors. Nanjing county and Minqing county are located in inland Fujian and have similar general demographics. However, the adjusted mortality rate of gastric cancer in Minqing was found to be much higher than that in Nanjing. We sought to explore factors associated with this increased risk of gastric cancer between the two counties. METHODS: We recruited 231 and 224 residents from Nanjing and Minqing, respectively, and analyzed differences between their dietary habits, Helicobacter pylori infection rates, and concentrations of serum pepsinogen I, pepsinogen II, gastrin-17, and ratio of pepsinogen I:II. RESULTS: Subjects in Minqing had more first-degree relatives who had been diagnosed with upper gastrointestinal tumor, more unhealthy dietary habits, a higher Helicobacter pylori positive rate, and greater proportion of abnormal serum gastrin-17 than those in Nanjing did. CONCLUSIONS: The factors that differed between these two counties might indicate that residents in Minqing have a higher risk for developing gastric cancer than those in Nanjing do.
Adult ; Aged ; China/epidemiology ; Female ; Food Habits ; Gastrins/blood ; Helicobacter Infections/epidemiology/microbiology/pathology ; Helicobacter pylori ; Humans ; Male ; Middle Aged ; Pepsinogen A/blood ; Pepsinogen C/blood ; Risk Factors ; Stomach Neoplasms/*diagnosis

OBJECTIVETo establish an animal model of gastric cancer by long-term infection of Helicobacter pylori (H.pylori) and to elucidate the pathogenesis by proteomics analysis.

METHODSFifty male Mongolian gerbils (4-5 week-old and weighted 60-100 g) were infected with H.pylori and the gastric tissues were obtained after the infection at 3, 6, 12 and 24 months. Histological changes were evaluated by H-E staining of the gastric tissue sections. Detection of H.pylori was performed by in-vitro culture of fresh gastric tissue samples, PCR amplification of H.pylori 16s rRNA and localization by silver staining. In addition, proteins extracted from gastric tissue samples were subjected to two-dimensional electrophoresis (2-DE) at various infection time points. Protein spots with increased quantity over the course of H.pylori infection were selected and analyzed by LC-MS/MS. Finally, differentially expressed proteins between human gastric cancer tissue samples and lymph nodes were analyzed by real-time RT-PCR.

RESULTSColonization of H.pylori was observed in gastric tissue of gerbils as early as 3 months after H.pylori infection, and persisted till 24 months. Pathological examination of infected animals showed various histological changes including acute gastritis, atrophic gastritis, intestinal metaplasia and gastric carcinoma. Seventy-eight differentially expressed proteins were identified by proteomics analysis, among which 36 proteins were up-regulated and 42 were down-regulated. Analyzed by LC-MS/MS, ten proteins were identified, including lactate dehydrogenase, ATP synthase, fatty acid-binding protein, COX5B, peroxiredoxin-4, peroxide reductase, transgelin, succinyl-CoA ligase, keratin and protein disulfide-isomerase A2, among which transgelin, ATP synthase and lactate dehydrogenase were highly expressed in human gastric carcinoma and lymph nodes.

CONCLUSIONSH.pylori infection induces the expression of transgelin, ATP synthase and lactate dehydrogenase, implying possible roles in the pathogenesis of gastric diseases including cancer.

Animals ; Disease Models, Animal ; Gastritis ; microbiology ; pathology ; Gerbillinae ; Helicobacter Infections ; complications ; metabolism ; Helicobacter pylori ; genetics ; Humans ; L-Lactate Dehydrogenase ; metabolism ; Male ; Metaplasia ; Microfilament Proteins ; metabolism ; Muscle Proteins ; metabolism ; Proteomics ; Proton-Translocating ATPases ; metabolism ; RNA, Ribosomal, 16S ; analysis ; Stomach Neoplasms ; metabolism ; microbiology ; Tandem Mass Spectrometry

OBJECTIVE: To explore the relationship between the Helicobacter pylori (H.pylori) infection and gastric mucosa change and blood-lipid in people undergoing the physical examination in Changsha. METHODS: A total of 2 264 people undergoing physical examination were divided into an H. pyloripositive group (n=1 068) and an H. pylori-negative group (n=1 196). Gastric mucosa change was diagnosed by gastroscopy, blood-lipid and blood sugar were detected, and the statistical analysis was performed. RESULTS: The incidence rate of H.pylori infection was 47.2%. The incidence rate of gastric mucosal erosion, gastric ulcer, duodenal ulcer, gastric mucosal atrophy, gastric polyp, dyslipidemia, increase of triglyceride were (TG) and decrease of the high density lipoprotein cholesterol (HDL-C) in the H.pylori-positive group were all higher than those in the H.pylori-negative group (P<0.01 or P<0.05). In the H. pylori-positive group, the level of TG in people with gastric mucosal erosion, gastric ulcer and duodenal ulcer was higher than that in people with normal gastric mucosa or mild gastritis, and HDL-C was lower than that in people with normal gastric mucosa or mild gastritis. CONCLUSION H. pylori infection can induce the gastric mucosa injury and dyslipidemia, which may result in the occurrence and development of coronary heart disease by increasing TG and decreasing HDL-C, thus increasing the risk of atherosclerosis.
Adenomatous Polyps ; Cholesterol, HDL ; blood ; Duodenal Ulcer ; microbiology ; physiopathology ; Dyslipidemias ; microbiology ; Gastric Mucosa ; microbiology ; pathology ; Gastritis ; microbiology ; physiopathology ; Helicobacter Infections ; physiopathology ; Helicobacter pylori ; Humans ; Lipids ; blood ; Physical Examination ; Stomach Neoplasms ; Stomach Ulcer ; microbiology ; physiopathology ; Triglycerides ; blood

Gastric cancer is one of the most common malignancies and a leading cause of cancer mortality worldwide. The pathogenesis mechanisms of gastric cancer are still not fully clear. Inactivation of tumor suppressor genes and activation of oncogenes caused by genetic and epigenetic alterations are known to play significant roles in carcinogenesis. Accumulating evidence has shown that epigenetic silencing of the tumor suppressor genes, particularly caused by hypermethylation of CpG islands in promoters, is critical to carcinogenesis and metastasis. Here, we review the recent progress in the study of methylations of tumor suppressor genes involved in the pathogenesis of gastric cancer. We also briefly describe the mechanisms that induce tumor suppressor gene methylation and the status of translating these molecular mechanisms into clinical applications.
Apoptosis ; Cell Adhesion ; Cell Cycle ; CpG Islands ; genetics ; DNA Methylation ; DNA Repair ; Epigenesis, Genetic ; Genes, Tumor Suppressor ; Helicobacter Infections ; genetics ; Helicobacter pylori ; Humans ; Neoplasm Invasiveness ; Promoter Regions, Genetic ; genetics ; Stomach Neoplasms ; genetics ; metabolism ; microbiology ; pathology ; Tumor Suppressor Proteins ; genetics ; metabolism