Naoko Maruyama

Selenoprotein S (SEPS1) gene -105G>A promoter polymorphism influences the susceptibility to gastric cancer in the Japanese population

BackgroundInflammation is a key factor in the process of carcinogenesis from chronic gastritis induced by Helicobacter pylori. Selenoprotein S (SEPS1) is involved in the control of the inflammatory response in the endoplasmic reticulum (ER). Recently the -105G>A polymorphism in the promoter of SEPS1 was shown to increase pro-inflammatory cytokine expression. We examined the association between this polymorphism and the risk of gastric cancer.MethodsWe took stomach biopsies during endoscopies of 268 Japanese gastric cancer patients (193 males and 75 females, average age 65.3), and 306 control patients (184 males and 122 females, average age 62.7) and extracted the DNA from the biopsy specimens. All subjects provided written informed consent. For the genotyping of the SEPS1 promoter polymorphism at position -105G>A, PCR-RFLP methods were used and the PCR products were digested with PspGI.Logistic-regression analysis was used to estimate odds ratios (OR) and 95% confidence intervals (CI), adjusting for age, sex, and H. pylori infection status.ResultsAmong cases, the distribution of genotypes was as follows: 88.4% were GG, 11.2% were GA, and 0.4% were AA. Among controls, the distribution was as follows: 92.5% were GG, 7.2% were GA, and 0.3% were AA. Among males, carrying the A allele was associated with an increased odds of gastric cancer, compared with the GG genotype (OR: 2.0, 95% CI 1.0–4.1, p = 0.07). Compared with the GG genotype, carrying the A allele was significantly associated with increased risks of intestinal type gastric cancer (OR: 2.0, 95%CI 1.0–3.9, p < 0.05) as well as of gastric cancer located in the middle third of the stomach (OR: 2.0, 95%CI 1.0–3.9, p < 0.05).ConclusionThe -105G>A promoter polymorphism of SEPS1 was associated with the intestinal type of gastric cancer. This polymorphism may influence the inflammatory conditions of gastric mucosa. Larger population-based studies are needed for clarifying the relation between inflammatory responses and SEPS1 polymorphism.

Increased number of methylated CpG islands correlates with Helicobacter pylori infection, histological and serological severity of chronic gastritis.

Background Promoter hypermethylation of tumor suppressor genes is one of the major events in gastric carcinogenesis. Promoter hypermethylation is also present in non-neoplastic gastric epithelium as age-related phenomenon and some reports suggest the potential association between promoter hypermethylation and Helicobacter pylori infection. Here, we examined whether methylation of multiple promoter CpG islands would occur by H. pylori infection and correlate with histological or serological severity of chronic gastritis. Methods One hundred and ninety-one gastric mucosa samples were obtained by endoscopy. The promoter methylation status of the p14, p16, DAP-kinase and CDH1 genes were determined by methylation-specific-polymerase chain reaction. The degree of gastritis in the antrum was assessed according to the updated Sydney system in 150 participants. The pepsinogen (PG) I/II ratio was calculated based on the data of serum PG I and PG II levels measured by radioimmunoassay in 54 selected cases. Results CpG island methylation was found in 32.5% for p14, 35.1% for p16, 43.5% for DAP-kinase and 36.1% for CDH1, whereas non, 1, 2, 3, and all methylation of four promoter CpG sites were present in 46 (24.1%), 59 (30.9%), 46 (24.1%), 30 (15.7%), and 10 (5.2%) participants, respectively. A strong association between the increased number of methylated CpG islands and H. pylori infection was observed (P<0.0001). An increased number of methylated CpG islands was also associated with severity of neutrophil infiltration (P<0.0001), mononuclear cell infiltration (P<0.0001) and atrophy (P=0.0021) in all, and severity of neutrophil infiltration (P=0.0177) and mononuclear cell infiltration (P=0.0004) in H. pylori-positive participants. An increased number of methylated CpG islands correlated with lower PG I/II ratio in all (P=0.0105) and H. pylori-infected participants (P=0.074). Conclusion Multiple promoter CpG islands would be methylated by H. pylori infection, and an increased number of methylated CpG sites correlate with histological and serological severity of chronic gastritis.

Correlation between magnifying narrow band imaging and histopathology in gastric protruding/or polypoid lesions: a pilot feasibility trial

BackgroundSeveral study showed usefulness of microscopic capillaries, seen by magnifying narrow band imaging (NBI) endoscopy for predicting histopathology among superficial depressed or flat elevated gastric neoplasia (GN). Here we assessed the diagnostic efficacy of magnifying NBI for predicting histopathology among gastric protruding/or polypoid lesions.MethodsUsing endoscopic pictures of magnifying NBI from 95 protruding/or polypoid lesions (19 fundic gland polyps: FGP, 47 hyperplastic polyps: HP, and 29 GN), fine mucosal patterns were classified into four categories: small round, prolonged, villous or ridge, and unclear patterns, and micro vascular patterns were classified into five categories: honey comb, dense vascular, fine net work, core vascular, and unclear patterns.ResultsMost suggestive micro vascular patterns for predicting FGP, and HP were honeycomb (sensitivity 94.7%, specificity 97.4%), and dense vascular patterns (sensitivity 93.6%, specificity 91.6%), respectively. Fine net work, core vascular, and unclear patterns presented higher specificity (97%, 100%, and 100%) for predicting GN, and diagnostic efficacy of combined of those patterns was favorable (sensitivity 86.2%, specificity 97.0%).ConclusionMicro vascular patterns by using magnifying NBI provides meaningful information for predicting the histopathology of gastric protruding/or polypoid lesions.

Downregulation of anti-oncomirs miR-143/145 cluster occurs before APC gene aberration in the development of colorectal tumors

Accumulating data indicate that some microRNAs (miRNAs or miRs) can function as tumor suppressors or oncogenes and as such are important in cancer development. We previously reported that miR-143 and -145 are frequently downregulated in colon adenomas and cancers, acting as tumor suppressors. In this present study, we investigated the relationship between the downregulation of the miR-143/145 cluster and genetic aberrations of adenomatous polyposis coli (APC), which are early genetic events in the development of colorectal tumors. The expression levels of both miRs were determined by performing real-time PCR on tissue samples of familial adenomatous polyposis (FAP), colorectal adenoma, colorectal cancer, and paired non-tumorous tissues. Also, the expression of C- or N-terminus of the APC protein and that of the p53 protein in these tissues were examined immunohistochemically. Our data clearly indicated that the decreased expression of miR-143 and -145 frequently occurred before APC gene aberrations. The downregulation of miR-143 and -145 is thus an important genetic event for the initiation step in colorectal tumor development.

Increased Number of CpG Island Hypermethylation in Tumor Suppressor Genes of Non-Neoplastic Gastric Mucosa Correlates with Higher Risk of Gastric Cancer

Background/Aim: We investigated the relationship of gastric cancer (GC) and CpG island hypermethylation (CIHM) in tumor suppressor genes of non-neoplastic gastric mucosa. Methods: Gastric mucosa samples were obtained from 125 GC and 180 non-GC subjects. CIHM of p14, p16, DAP-kinase and CDH1 genes were determined by methylation-specific polymerase chain reaction. High CIHM was defined as three or all methylated CpG islands. Results: Rates of CIHM of p14, CDH1, DAP-kinase, and high CIHM were significantly higher in all GC samples than non-GC samples (p14: 32.2 vs. 50.4%; OR = 1.70, 95% CI = 1.03–2.80, p = 0.04, CDH1: 36.1 vs. 84.0%; OR = 8.65, 95% CI = 14.74–15.77, p < 0.0001, DAP-kinase: 42.2 vs. 83.2%; OR = 5.98, 95% CI = 3.37–10.62, p < 0.0001, and high CIHM: 44.4 vs. 80.8%; OR = 4.40, 95% CI = 2.51–7.72, p < 0.0001). CIHM in CDH1 and DAP-kinase were associated with a greater risk of GC including all of its different subtypes. An increased number of CIHM was associated with an increased risk of all GC (1 CIHM; OR = 2.33, 95% CI = 0.82–6.64, p = 0.11, 2 CIHM; OR = 4.89, 95% CI = 1.79–13.37, p = 0.002, 3 CIHM; OR = 9.43, 95% CI = 3.20–27.78, p < 0.0001, and all CIHM OR = 24.71, 95% CI = 6.70–91.18, p < 0.0001). Three and all CIHM were closely associated with a higher risk of intestinal-type GC, Helicobacter pylori-positive infection status, male gender, and middle and older GC while 3 CIHM was closely associated with a higher risk of diffuse-type GC, H. pylori-negative infection status and younger GC. Conclusions: CIHM of CDH1 and DAP-kinase in non-neoplastic gastric mucosa corresponded to a risk of GC regardless of histological subtype, H. pylori infection status, gender and generation. An increased number of CIHM correlates with a higher GC risk including its various clinico-pathological subtypes.

A Genetic Variant of the CD14 C-159T in Patients with Functional Dyspepsia (FD) in Japanese Subjects.

Inflammatory changes in the gastric mucosa are commonly observed in Japanese patients with functional dyspepsia (FD). However, detailed data regarding the relationship between the genetic regulatory factors of inflammation and FD are not available. CD14 is an important mediator of the inflammatory response in the first line of host defense by recognition of Lipopolysaccharide (LPS). We aimed to investigate the association between CD14 promoter C-159T polymorphism and FD in a Japanese population. 108 patients with FD and 99 non-dyspeptic subjects enrolled in this study. Dyspeptic symptoms were divided according to Rome III criteria. CD14 gene C-159T polymorphism was determined by polymerase chain reaction-restriction fragment length polymorphism. In the non-dyspeptics, the CD14 genotype distribution was 28CC (28.3%), 51CT (51.5%), 21TT (21.2%). Meanwhile, the CD14 genotype distribution in FD was 31CC (28.4%), 56CT (51.4%), 22TT (20.2%). The genotype distribution was not significantly different. There was no significant difference between two groups in the genotype distribution. We did not found any association between CD14 genotypes and dyspeptic patients in different gender and Helicobacter pylori infection status. No significant association was also found between CD14 polymorphism and any of different subtypes of FD according to Rome III while there was a weak correlation between TT genotype and PDS in male subjects (TT vs others, OR = 3.18, 95% CI = 0.98−10.26, p = 0.06). In conclusion, our results suggest that CD14 polymorphism is unlikely to associate with susceptibility of dyspeptic symptoms. The role of inflammation related-gene polymorphisms to the development of dyspepsia needs to further evaluation.

Role of heat-shock protein (HSP) 70-2 genotype in peptic ulcer in Japanese population.

BACKGROUND/AIMS There have been reports showing the protective role of inducible heat-shock protein (HSP) 70 in gastric epithelial cells. An A to G transition at the 1267 position HSP70-2 gene has been shown to be associated with a different level of HSP70 mRNA expression. We aimed to clarify the effect of HSP70-2 polymorphism on the risk of peptic ulcer diseases in a Japanese population. METHODOLOGY A total of 519 subjects participated in this study. All subjects underwent upper gastroscopy. Restriction fragment length polymorphism analysis was performed for polymorphisms at 1267 of HSP70-2 gene in all the subjects. RESULTS After gastroscopy, 109, 53 and 357 subjects were diagnosed as gastric ulcer, duodenal ulcer and non-ulcer subjects, respectively. Although, there were no significant differences of HSP70-2 genotype distributions among nonulcer subjects, overall ulcer, gastric and duodenal ulcers when the subjects were divided into two groups according to age distribution, logistic regression analysis showed that the BB genotype increased the risk of duodenal ulcer in subjects 60 years and older. (Gender, status of H. pylori infection and NSAID use adjusted OR=3.12, 95%CI=1.33-7.35, p=0.009). CONCLUSIONS It appears that polymorphism of HSP70-2 gene is not directly associated with the susceptibility to peptic ulcer diseases but BB genotype is associated with an increased risk of duodenal ulcer in older subjects in the Japanese population.

Mannan-binding lectin B allele is associated with a risk of developing more severe gastric mucosal atrophy in Helicobacter pylori-infected Japanese patients.

Objective Mannan-binding lectin (MBL) is an important constituent of the innate immune system, and deficiency of MBL has been reported to increase the overall susceptibility of an individual to infectious disease. Codon 54 G/A variant of exon 1 (B allele) affects MBL2 gene and alters its activity. We investigated the influence of MBL2 variant on the risk of gastroduodenal diseases and on the severity of Helicobacter pylori-induced gastritis in a Japanese population. Methods One hundred and two gastric ulcers, 48 duodenal ulcers, 275 nonulcer participants were included in this study. B allele of the MBL2 gene was detected by polymerase chain reaction based restriction fragment length polymorphism. The severity of the histological chronic gastritis in antral biopsy specimens were classified according to the updated Sydney system. Results MBL2 B allele was significantly associated with severity of gastric mucosal atrophy and intestinal metaplasia (atrophy, G/G vs. G/A vs. A/A; P=0.02, A/A vs. others; P=0.009, intestinal metaplasia; G/G vs. G/A vs. A/A; P=0.03, A/A vs. others; P=0.004). When participants were divided into the following three groups according to the severity of gastric atrophy: the nonatrophic gastritis (NA) group, the severe atrophic gastritis (SA) group, and mild atrophic gastritis (MA) group, the frequency of A/A was significantly higher in the SA group than in others (SA vs. MA; odds ratio=8.42, 95% confidence interval=1.05–67.45, SA vs. others; odds ratio=10.06, 95% confidence interval=1.26–80.45). Conclusion Our data suggest that the MBL2 codon 54 B allele is associated with a risk of developing more severe gastric mucosal atrophy in H. pylori-infected Japanese patients.

Examination of serum pepsinogen in functional dyspepsia.

BACKGROUND/AIMS Although serum pepsinogen (PG) is considered as a marker of gastric atrophy, it also reflects gastric acid secretion, which closely influences dyspeptic symptoms. We investigated serum PG levels and PGI/PGII ratios in dyspeptic patients, in relation to various different subtypes of symptoms including Rome III classifications. METHODOLOGY Serum PGs were measured in 75 subjects with dyspeptic symptoms and 42 asymptomatic healthy subjects. RESULTS PG II level was significantly higher (p=0.0001) and PG I/II ratio was significantly lower (p<0.0001) in subjects with H. pylori infection than those without, while no associations were found between PG levels and usage of H2 receptor antagonists or proton-pump inhibitors. In all subjects with pain in stomach, abdominal bloating and PDS-like symptoms according to Rome III criteria, presented significantly higher levels of PGI, compared to subjects without symptoms (p=0.043, 0.015 and 0.037, respectively). In addition, burning sensation and abdominal pain presented significantly higher PGI/II ratios (p=0.0005 and 0.003, respectively), and higher PGI/II ratio was also positively correlated with a number of symptoms (p=0.04). When subjects were divided according to H. pylori infection status, higher PGI/II ratio was significantly associated with abdominal pain in H. pylori negative subjects (p=0.03), while higher PGI level was significantly associated with functional esophageal disorders (FEG) according to Rome III criteria, and higher number of dyspeptic symptoms in H. pylori positive subjects (p=0.016). CONCLUSIONS Our data suggest that subjects with higher PGI level, and PG I/II ratio are more likely to develop several dyspeptic symptoms.

Gastrointestinal Stromal Tumor of the Stomach with Narrow Stalk-Like Based, Uneven Protruding Appearance Presenting with Severe Acute Anemia despite Small Size

We report the case of a 56-year-old woman who had a gastrointestinal stromal tumor (GIST) of the stomach. She was admitted to our hospital for epigastric pain, nausea, and severe acute anemia (hemoglobin level 4.3 g/dl). Esophagogastroduodenoscopy revealed a narrow stalk-like based, hemorrhagic and uneven protruding lesion in the lesser curvature of the gastric upper corpus. Although the tumor was less than 2 cm in diameter and was probably a benign GIST according to histology, laparoscopy-assisted local resection was needed because the patient had continuous severe anemia and epigastric pain. Histological assessment showed that the elongated spindle-like tumor cells originated from the intrinsic muscle layer, and was shown with growth to the mucosal side, cropping out to the surface in most areas of the protruding lesion. Only a small part of the tumor was within nontumoral gastric mucosa. Most of the tumor cells demonstrated immunoreactivity for KIT and CD34 in the cytoplasm but not for αSMA, S100, and desmin. Mitotic activity (0/50 high power field) and the labeling index for MIB-1 (about 1%) were low. The GIST of the stomach described in this report was a rare case with a narrow stalk-like based, uneven protruding mass presenting with severe acute anemia despite small size.