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

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

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

OBJECTIVETo evaluate the H. pylori and Epstein-Barr virus infection in cardiac and distal gastric adenocarcinoma tissues in residents in Cixian county, a high risk area of esophageal cancer in Hebei province, and to explore the putative role of H. pylori and Epstein-Barr virus infection in the carcinogenesis of adenocarcinoma at different subsites of stomach.

METHODSH. pylori and Epstein-Barr virus latent membrane protein 1 (EBV-LMP1) immunopositivities were determined by Elivision(TM) plus immunohistochemical staining in 190 gastric adenocarcinoma tissues including 144 cases of cardiac adenocarcinoma and 46 cases of distal gastric adenocarcinoma. The relationship between H. pylori and Epstein-Barr virus infection and the subsite, Laurén type as well as other clinicopathological features of gastric adenocarcinoma were analyzed.

RESULTSNo significant difference was found between the H. pylori detection rates in cardiac and distal gastric adenocarcinomas(56.9% vs. 65.2%, P > 0.05). The detection rate of H. pylori in intestinal type was significantly higher than that in the diffuse type distal gastric adenocarcinomas (71.8% vs. 28.6%, P < 0.05). No positive expression of EBV-LMP1 was found in the gastric adenocarcinomas in this study.

CONCLUSIONSNo significant differences in H. pylori and EBV-LMP1 infections were found between cardiac and distal gastric adenocarcinomas in Cixian county. H. pylori infection is related with the intestinal type of distal gastric adenocarcinoma.

Adenocarcinoma ; microbiology ; pathology ; virology ; Aged ; Cardia ; China ; Epstein-Barr Virus Infections ; pathology ; Female ; Helicobacter Infections ; pathology ; Helicobacter pylori ; isolation & purification ; Humans ; Male ; Middle Aged ; Stomach Neoplasms ; microbiology ; pathology ; virology ; Viral Matrix Proteins ; metabolism

OBJECTIVETo investigate the regulatory effect of jianpi jiedu Recipe (JJR) on the microvessel density (MVD) and cyclooxygenase-2 (COX-2) in long-term infection of Helicobacter pylori induced gastric cancer of C57BL/6 mice, thus providing experimental bases for its treatment of the H. pylori correlated gastropathy.

METHODSC57BL/6 mouse gastric cancer model induced by H. pylori infection was established by gastrogavage of H. pylori standard strain SS1. Mice were divided into the control group, the model group, low dose JJR group, and the high dose JJR group, 40 in each group. Mice were sacrificed after 72-week medication. Changes of the gastric mucosa MVD of mice in each group were detected by immunohistochemical method. Expressions of COX-2 mRNA and protein were detected by Real-time fluorescent quantitative polymerase chain reaction and immunohistochemical method.

RESULTSThe occurrence rate of gastric cancer in the control group, the model group, the low dose JJR group, and the high dose JJR group was 0, 22.2%, 11.1%, and 10.0%, respectively. The gastric mucosa MVD (number/cm2) of mice in each group was 2.50 +/- 1.54, 18.56 +/- 2.62, 14.61 +/- 3.60, and 7.39 +/- 1.75, respectively. The gastric mucosa MVD in the model group increased more obviously than that in the control group (P < 0.01). The gastric mucosa MVD significantly decreased in the low dose JJR group and the high dose JJR group (P < 0.01). Expressions of COX-2 mRNA and protein in the model group increased more obviously than those in the control group (P < 0.01). Low dose JJR and high dose JJR could decrease their expressions in a dose dependent manner.

CONCLUSIONSH. pylori infection could increase the gastric mucosa MVD of C57BL/6 mice and promote COX-2 expressions, which might play a promoting effect in the incidence of H. pylori induced gastric cancer. JJR could decrease the gastric mucosa MVD and inhibit COX-2 expressions, which might be one of its important mechanisms of preventing and treating gastric cancer.

Animals ; Cyclooxygenase 2 ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Gastric Mucosa ; blood supply ; drug effects ; metabolism ; Helicobacter Infections ; metabolism ; Helicobacter pylori ; Mice ; Mice, Inbred C57BL ; Microvessels ; pathology ; Stomach Neoplasms ; blood supply ; metabolism ; microbiology

Intestinal metaplasia (IM) has been regarded as a premalignant condition. However, the pathogenesis of IM is not fully understood. The aim of this study was to evaluate the role of CDX1 and CDX2 in the formation of IM and the progression to dysplasia and gastric cancer (GC). A total of 270 subjects included 90 with GC, dysplasia and age- and sex-matched controls. Real-time PCR (RT-PCR) was performed with body specimens for CDX1 and CDX2. The expression of CDX2 was significantly higher in H. pylori positive group than H. pylori negative group (P = 0.045). CDX1 and CDX2 expression increased proportional to the IM grade of the body (P < 0.001). CDX2 expression was significantly higher in incomplete type of IM than in complete type (P = 0.045). The expression of CDX1 in dysplasia group was significantly higher than in the control group (P = 0.001); in addition, CDX1 and CDX2 in cancer group was significantly higher than control group (P < 0.001, and P < 0.001, respectively). Aberrant expression of CDX1 and CDX2 correlated with H. pylori infection and grade of IM in the body. Furthermore, the results suggest that CDX1 and CDX2 play a role in the progression to GC and dysplasia.
Aged ; Female ; Helicobacter Infections/complications/microbiology ; Helicobacter pylori/isolation & purification ; Homeodomain Proteins/*genetics/metabolism ; Humans ; Intestinal Diseases/*genetics/microbiology/pathology ; Male ; Metaplasia/pathology ; Middle Aged ; Polymerase Chain Reaction ; Precancerous Conditions/metabolism/pathology ; Stomach Neoplasms/etiology/*genetics/microbiology

OBJECTIVETo investigate the expression feature of heterogeneous nuclear ribonucleoprotein K in gastric carcinoma and its clinical significance, and to explore the relationship between hnRNPK expression and Helicobacter pylori L-form infection.

METHODSThe expression of hnRNPK protein was examined in 100 cases of gastric carcinoma, 50 paracancerous gastric tissues and 30 matched normal gastric mucosa by Elivision immunohistochemistry and hnRNPK-mRNA by in situ hybridization. Hp-L was detected with Gram staining and immunohistochemical staining.

RESULTSThe positive rates of hnRNPK protein and mRNA in gastric carcinoma were 82.0% and 86.0%, respectively, significantly higher than those in the paracancerous gastric tissues and normal controls (P < 0.05). The expression of hnRNPK protein was significantly correlated with histological differentiation, TNM stage and lymph node metastasis (P < 0.05). The positive rates of Hp-L in the three groups were 67.0%, 58.0% and 23.3%, respectively. The positive rate of Hp-L in gastric carcinoma had no significant correlation with it in the paracancerous gastric tissues, but was significantly higher than it in the normal controls (P < 0.05). In gastric carcinoma, the expression of hnRNPK protein was higher in cases of Hp-L positive patients than those of Hp-L negative cases (P < 0.05). Positive correlation existed between the expression of hnRNPK protein and Hp-L infection (r = 0.391, P < 0.01).

CONCLUSIONSThere is a higher expression of hnRNPK in gastric carcinoma. Hp-L infection may be associated with the up-regulated hnRNPK expression. The two factors may play a synergetic role in gastric carcinogenesis.

Adult ; Aged ; Aged, 80 and over ; Female ; Gastric Mucosa ; metabolism ; Helicobacter Infections ; metabolism ; microbiology ; Helicobacter pylori ; Heterogeneous-Nuclear Ribonucleoprotein K ; Humans ; Lymphatic Metastasis ; Male ; Middle Aged ; Neoplasm Staging ; Precancerous Conditions ; metabolism ; microbiology ; pathology ; RNA, Messenger ; metabolism ; Ribonucleoproteins ; genetics ; metabolism ; Stomach Neoplasms ; metabolism ; microbiology ; pathology

Adult ; Aged ; Aged, 80 and over ; Female ; Helicobacter Infections ; metabolism ; Helicobacter pylori ; classification ; pathogenicity ; Humans ; Lymphatic Metastasis ; Male ; Microvessels ; pathology ; Middle Aged ; Neoplasm Invasiveness ; Neovascularization, Pathologic ; microbiology ; pathology ; Stomach Neoplasms ; blood supply ; metabolism ; microbiology ; Vascular Endothelial Growth Factors ; metabolism

OBJECTIVETo investigate the protein expression of cyclooxygenase 2 (COX-2) and nuclear factor kappa B (NF-kappaB) in gastric mucosa-associated lymphoid tissue (MALT) lymphoma and its clinical significance.

METHODSProtein expression of COX-2 and NF-kappaB in gastric MALT lymphoma were examined by immunohistochemistry of Envision two-step method. The correlations of COX-2 and NF-kappaB expression with Helicobacter pylori (Hp) infection, clinical stage, depth of tumor invasion, tumor size, recurrent rate and treatment were analyzed by univariate, multivariate and Pearson analysis.

RESULTSThe positive expression of COX-2 and NF-kappaB in gastric MALT lymphoma were 48.9%(23/47) and 36.2% (17/47) respectively, and a positive correlation was found between these two factors(r=0.326,P<0.05). Moreover, COX-2 expression was positively correlated with Hp infection,clinical stage, depth of invasion and tumor size (P<0.05). Univariate analysis showed that the overall survival of gastric MALT lymphoma patients with positive COX-2 protein (59.9 months) was shorter than that of patients with negative COX-2 protein (77.8 months), but the difference was not significant (P>0.05). The survival was significantly shorter in gastric MALT lymphoma patients with positive NF-kappaB protein (26 months) than that of patients with negative NF-kappaB protein (123.2 months)(P<0.05). Multivariate Cox regression analysis revealed that clinicopathological stage was independent prognostic factor, and associated with short survival.

CONCLUSIONUp-regulated expression of COX-2 and activation of NF-kappaB are associated with Hp infection in gastric MALT lymphoma, and their protein expression is correlated with the development of tumor and prognosis.

Cyclooxygenase 2 ; metabolism ; Female ; Gastric Mucosa ; metabolism ; microbiology ; Helicobacter Infections ; metabolism ; Helicobacter pylori ; Humans ; Lymphoma, B-Cell, Marginal Zone ; metabolism ; microbiology ; pathology ; Male ; Middle Aged ; NF-kappa B ; metabolism ; Neoplasm Staging ; Prognosis ; Stomach Neoplasms ; metabolism ; microbiology ; pathology