Molecular subtyping of gastric cancer combining genetic and epigenetic anomalies provides distinct clinicopathological features and prognostic impacts.

Both genetic and epigenetic abnormalities play important roles in gastric cancer (GC) development. We investigated whether the molecular subtypes of gastric cancer by combining genetic and epigenetic anomalies define its clinicopathological features and prognosis. The CpG island methylator phenotype (CIMP), MLH1 methylation, TP53, and KRAS mutation statuses were characterized in 214 GCs in relation to their clinicopathological features and prognosis. The molecular subtypes based on CIMP and TP53 hot spot mutation status (R175, G245, R248, R273, and R282) best predicted prognosis of GC. These subtypes contained 120 CIMP-positive (CIMP+) TP53 hot spot mutation-negative (TP53 hot spot-) cases, 81 CIMP-negative (CIMP-) TP53 hot spot- cases, 8 CIMP+TP53 hot spot mutation-positive (TP53 hot spot+) cases, and 5 CIMP- TP53 hot spot+ cases. The CIMP-TP53 hot spot+ group presented the worst overall survival (OS) and progression-free survival (PFS), followed by the CIMP+TP53 hot spot+, CIMP-TP53 hot spot- and CIMP+TP53 hot spot- groups (both P < 0.0001). These subtypes also correlated well with several aggressive clinicopathological features in that order. The molecular subtypes were independent factors for predicting overall survival (hazard ratio = 1.66, 95% CI = 1.07-2.57, P = 0.006). The molecular subtypes combining the CIMP and TP53 hot spot mutation status provide distinct clinicopathological features and prognostic impacts in GC.

DNA methylation accumulation in gastric mucosa adjacent to cancer after Helicobacter pylori eradication.

Molecular irreversibleness with Helicobacter pylori (H. pylori) infection might have a role in gastric tumorigenesis after H. pylori eradication. We performed comprehensive DNA methylation profiling of gastric mucosa after H. pylori eradication with or without gastric cancer. Using four different groups of biopsies obtained from gastric body without history of H. pylori infection (Hp-), gastric body without cancer after H. pylori eradication (cancer-free body), gastric body with early gastric cancer diagnosed after H. pylori eradication (EGC body) and their paired samples from adjacent mucosa of cancer (EGC ADJ), methylation status of five candidate genes (MYOD1, SLC16A12, IGF2, RORA and PRDM5) was examined by the bisulfite pyrosequencing. An Infinium Methylation EPIC BeadChip array was also used to characterize the methylation status of greater than 850,000 CpG sites. The EGC ADJ group showed highest methylation levels of five candidate genes among the four groups of biopsies. In the gastric body (cancer-free body + EGC body), methylation levels were significantly decreased in patients with longer period after eradication, while such association was not observed in EGC ADJ group. Hyper methylated samples were associated with shorter telomere, an indicator for rapid cell turnover, and higher DNMT1 protein expression, an enzyme related to methyl transfer reaction. The genome-wide methylation analysis demonstrated strikingly higher methylation levels especially at CpG islands in the EGC ADJ group. Exclusively hypermethylated promoter CpG islands in the same group frequently coded zinc finger proteins. Our data show that DNA methylation accumulation is associated with molecular irreversibleness and gastric carcinogenesis after H. pylori eradication.

Gastric Mucosal Microarchitectures Associated with Irreversibility with Helicobacter pylori Eradication and Downregulation of Micro RNA (miR)-124a.

To investigate the molecular mechanisms of gastric carcinogenesis after Helicobacter pylori (H. pylori) eradication, expression of miR-124a, miR-34b, and miR-34c was examined in nonneoplastic gastric specimens after successful H. pylori eradication. The magnifying narrow-band imaging (NBI) endoscopic features of gastric mucosa were also examined. The atrophic type, an informative endoscopic feature for histological intestinal metaplasia, showed lower expression of miR-124a. Lower expression of miR-124a correlated with hypermethylation of the miR-124a3 locus. The atrophic type represents gastric microarchitectures associated with irreversibility with H. pylori eradication and downregulation of miR-124a.

In vivo diagnosis of early-stage gastric cancer found after Helicobacter pylori eradication using probe-based confocal laser endomicroscopy.

BACKGROUND AND AIM: Early-stage gastric cancer (EGC) found after Helicobacter pylori (Hp) eradication often displays non-tumorous regenerative epithelium and/or maturated tumorous epithelium overlying the cancerous tissue, which may confuse endoscopic and histological diagnosis. Probe-based confocal laser endomicroscopy (pCLE) enables in vivo real-time optical biopsy. We compared the diagnostic yields for these EGC cases using conventional white light endoscopy (WL), magnifying endoscopy with narrow-band imaging (ME-NBI), pCLE, and endoscopic biopsy; we also compared the accuracy of the horizontal extent diagnosis between ME-NBI and pCLE. METHODS: This study enrolled 30 patients with 36 EGC lesions after successful Hp eradication. Diagnostic yields of WL, ME-NBI, pCLE, and endoscopic biopsy were prospectively compared. Four points of cancerous margins (oral, anal, anterior, and posterior sites) were also prospectively evaluated with M-NBI and pCLE to determine the horizontal extent of the EGC. RESULTS: Diagnostic yield was significantly higher with pCLE than with WL and endoscopic biopsy (97 vs 72%, 97 vs 72%, P = 0.0159, 0.0077, respectively), whereas it did not differ from ME-NBI (88.9%, P = 0.371). Height of non-tumorous regenerative epithelium or maturated atypical glands was 104.7 ± 34.2 µm in the pCLE-positive cases, whereas it was 188.3 ± 27.1 µm in a pCLE-negative case (P = 0.0004). Diagnostic accuracy of the horizontal margin of EGC was significantly higher with pCLE than with ME-NBI (92 vs 70%, P = 0.0159). CONCLUSION: pCLE may be helpful for the diagnosis of ambiguous ECG found after Hp eradication because it enables real-time scanning throughout the lesion and detection of subsurface microstructure.

Magnifying NBI Patterns of Gastric Mucosa After Helicobacter pylori Eradication and Its Potential Link to the Gastric Cancer Risk.

BACKGROUND: Gastric cancer develops after successful H. pylori eradication in patients with severe atrophic gastritis. We classified atrophic and non-atrophic mucosa of gastric body using magnifying NBI endoscopy in patients after successful H. pylori eradication. MATERIALS AND METHODS: One hundred and twenty-five patients after successful H. pylori eradication (median period after eradication: 36 months) were enrolled. Magnifying NBI patterns in the uninvolved gastric body were divided into the following: restored-small, round pits, accompanied with honeycomb-like subepithelial capillary networks; atrophic-well-demarcated oval or tubulovillous pits with clearly visible coiled or wavy vessels. The subjects were also classified into the three types: Grade 0-restored pattern is shown in all or almost the entire area of gastric body; Grade 1-mixture of restored and atrophic pattern, there is a considerable portion of the atrophic area in the lesser curvature; Grade 2-atrophic pattern is shown in all or almost the entire area of the gastric body. RESULTS: Sensitivity and specificity for atrophic type for detection of histological intestinal metaplasia were 95.9 and 98.3%, respectively. No association was observed between the prevalence of Grades 0, 1 and 2 and duration after eradication, while grades 1 and 2 were significantly frequent in gastric cancer patients diagnosed both before (27/35: 77%) and after (23/31: 74%) eradication, compared to the cancer-free subjects (15/59: 25%) (P < 0.001). The grades 1 and 2 were also common in patients who underwent H. pylori eradication for gastric ulcer. CONCLUSIONS: Magnifying the NBI pattern well correlates with pathological status of gastric mucosa after H. pylori eradication and may predict gastric cancer occurrence.

Fusobacterium detected in colonic biopsy and clinicopathological features of ulcerative colitis in Japan.

BACKGROUND AND AIMS: Fusobacterium species are part of the gut microbiome in humans, but some species have been recognized as opportunistic pathogens implicated in inflammatory diseases including inflammatory bowel diseases. Here, we performed prevalence screening of Fusobacterium in ulcerative colitis (UC) in Japanese patients. METHODS: We examined Fusobacterium nucleatum (F. nucleatum) and whole Fusobacterium species (Pan-fusobacterium) by quantitative real-time PCR in 163 inflamed mucosae from 152 UC patients. Data were correlated with clinical subtypes of UC. RESULTS: In an initial prevalence screen, F. nucleatum and Pan-fusobacterium were detected in 6.3 % (4/64) and 53.1 % (34/64). For all 163 mucosae, the prevalence of Pan-fusobacterium was 54.6 % (89/163). Pan-fusobacterium status was concordant in inflamed and normal adjacent samples, and the matched cases during 1-year follow-up colonoscopy. The higher amount of Pan-fusobacterium was observed in chronic continuous type compared to one attack and relapse/remitting type (p = 0.039). The higher amount of Pan-fusobacterium was also associated with rather mild clinical course of disease, such as non-steroid dependency (p = 0.015), non-refractory phenotype (p = 0.013), and non-severe phenotype (p = 0.04). Based on the distribution of Pan-fusobacterium measurable cases, we identified 10 cases as having a high amount of Pan-fusobacterium (FB-high). The clinicopathological features of FB-high UC cases were also highlighted by chronic continuous type and mild phenotypes of disease. CONCLUSION: Whole Fusobacterium species, but not F. nucleatum, are common in UC patients and have a role in persistence of colonic inflammation in UC. However, Fusobacterium infection is associated with rather mild clinical phenotypes of UC.

Light blue crest and ridge/villous patterns in the uninvolved gastric antrum by magnifying NBI endoscopy correlate with serum pepsinogen and gastric cancer occurrence.

BACKGROUND/AIMS: Combining the magnifying endoscopy and the narrow-band imaging (NBI) system is an endoscopic imaging technique for the enhanced visualization of mucosal microscopic structure and capillaries of the superficial mucosal layer. Light blue crest (LBC) and, ridge/villous pattern have been thought to be suggestive signs for gastric intestinal metaplasia (IM) of magnifying NBI endoscopy. Since the IM is related to gastric cancer risk (GC), the prevalence of LBC and ridge/villous pattern in the nonneoplastic gastric antrum was examined in relation to gastric cancer (GC) risk and serological severity of gastritis. METHODOLOGY: In 100 subjects including 13 GC patients, gastric mucosal pattern were examined using magnifying NBI. The mucosal patterns in the antrum were classified according to the presence of LBC or ridge/villous pattern. Serum pepsinogen (PG) levels were also examined. RESULTS: The sensitivity and specificity for predicting IM was the best when LBC and ridge/villous patterns were combined (sensitivity 95.2%, specificity 98.7%). Both LBC and ridge/villous pattern showed lower serum PGI and PGI/II ratio than those without (P = 0.046, 0.0005, respectively.) In particular, PGI/II ratio was lowest in ridge/villous pattern. The LBC and ridge/villous pattern showed higher incidence of all GC and diffuse GC compared to those without (P = 0.002, 0.002, respectively). CONCLUSIONS: LBC and ridge/villous pattern in uninvolved gastric antrum by magnifying NBI endoscopy are useful signs for predicting gastric atrophy in the entire stomach and GC risk.

Clinical, Pathological and Endoscopic Features of Neoplastic or Non-neoplastic Reddish Depressed Lesions after Helicobacter pylori Eradication.

BACKGROUND AND AIMS: Early gastric cancers (EGCs) after Helicobacter pylori (H. pylori) eradication often appear as reddish depressed lesions (RDLs); the same features are also appeared in benign stomachs after eradication. We compared clinic-pathological and endoscopic features of benign and neoplastic RDLs after H. pylori eradication. METHODS: 228 neoplastic RDLs after H. pylori eradication were studied. All lesions were divided into neoplastic RDLs (differentiated carcinoma or adenoma, n=114) and benign RDLs (n=114) according to the histology. Clinical and pathological characteristics were compared in neoplastic and benign groups. Endoscopic diagnostic yields using the white light (WL) endoscopy, chromoendoscopy (CE) using indigo carmine dye and the magnifying endoscopy with narrow-band imaging (ME-NBI) were also evaluated in relation to the pathological diagnosis. RESULTS: Size of neoplastic RDLs was larger than that of benign RDLs (p<0.01). Sensitivity, specificity and accuracy for predicting pathological types of RDLs was 70.1%, 52.6% and 61.4% for the WL, 65.8%, 63.1% and 65.4% for the CE, while the ME-NBI scored better with the 88.6%, 88.6%, 99.1% and 93.9% of sensitivity, specificity and accuracy. The accuracy of the ME-NBI was 99.9% (113/114) in the benign RDLs and 89.4% (101/114) for the neoplastic RDLs. Undiagnosed neoplastic RDLs using the ME-NBI were associated with more differentiated tumors such as adenoma and well-differentiated adenocarcinoma (tub1) and the presence of an unclear demarcation line. CONCLUSIONS: ME-NBI is useful to diagnose RDLs after H. pylori eradiation, while some of neoplastic lesions are difficult to diagnose using the ME-NBI.

A case of chronic gastric anisakiasis coexisting with early gastric cancer.

Background: Anisakiasis is a parasitic disease caused by the consumption of raw or undercooked fish that is infected with Anisakis third-stage larvae. In countries, such as Japan, Italy, and Spain, where people have a custom of eating raw or marinated fish, anisakiasis is a common infection. Although anisakiasis has been reported in the gastrointestinal tract in several countries, reports of anisakiasis accompanied by cancer are rare. Case presentation: We present the rare case of a 40-year-old male patient with anisakiasis coexisting with mucosal gastric cancer. Submucosal gastric cancer was suspected on gastric endoscopy and endoscopic ultrasonography. After laparoscopic distal gastrectomy, granulomatous inflammation with Anisakis larvae in the submucosa was pathologically revealed beneath mucosal tubular adenocarcinoma. Histological and immunohistochemical investigation showed cancer cells as intestinal absorptive-type cells that did not produce mucin. Conclusion: Anisakis larvae could have invaded the cancer cells selectively because of the lack of mucin in the cancerous epithelium. Anisakiasis coexisting with cancer is considered reasonable rather than coincidental. In cancer with anisakiasis, preoperative diagnosis may be difficult because anisakiasis leads to morphological changes in the cancer.

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

BACKGROUND: Several 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. METHODS: Using 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. RESULTS: Most 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%). CONCLUSION: Micro vascular patterns by using magnifying NBI provides meaningful information for predicting the histopathology of gastric protruding/or polypoid lesions.

Presence of minimal change esophagitis closely correlates with pathological conditions in the stomach.

INTRODUCTION: It is suggested that minimal change (grade M) esophagitis is a spectrum of gastric acid reflux disease. We evaluated the clinical significance of grade M esophagitis, including its subtypes (reddish change: MR and whitish change: MW), especially with attempt to pathological conditions in the stomach that relates to gastric acid secretion. MATERIALS AND METHODS: Using 241 subjects undergoing esophagogastroduodenoscopy for various indications, we investigated the association between grade M esophagitis with histological and serological severity of gastritis and endoscopic degree of atrophy. We also examined its association with ulcer diseases and various symptoms. RESULTS: When grade M cases were divided into MR and MW, all MR cases had MW in considerable degrees. Dyspeptic symptoms were more likely to be associated with H. pylori negative grade M cases, while presence of duodenal ulcer and its scar were associated with Helicobacter pylori-positive grade M cases. In all subjects, histological parameters, especially in the corpus, were lower in grade M cases compared to normal appearance. In grade M cases, degree of acute and chronic inflammation, and atrophy in corpus were lowest in cases that have grade MR. Grade M cases were also associated with higher pepsinogen I/II ratio and lower endoscopic atrophy. CONCLUSIONS: Pathological conditions of the stomach relate to higher gastric acid secretion correlates with grade M esophagitis. In grade M cases, appearance of MR may reflect higher gastric acid secretion or severe acid reflux than cases that have grade MW only.

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.

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.

Synergistic effect of IL-1ß and TNF-α polymorphisms on the H. pylori-related gastric pre-malignant condition.

BACKGROUND/AIMS: We investigated the effect of IL-1ß and TNF-α polymorphisms, and its synergistic effect with age, gender and H. pylori status on the gastric pre-malignant condition. METHODOLOGY: IL-1ß-31(T>C) and -511(C>T) and TNF-α-857 (C>T) polymorphisms were genotyped in 123 cancer free subjects. Degree of histological gastritis in both antrum and corpus, and extension of endoscopic gastric atrophy were also evaluated. RESULTS: Significant associations were found between degrees of mononuclear cell infiltration (p=0.007) and atrophy (p=0.01) in the antrum with IL-1ß-31(T>C) polymorphism, and degree of endoscopic gastric atrophy with both IL-1ß-31(T>C), -511(C>T) polymorphisms (p=0.03, 0.04, respectively). When subjects were divided into the 3 groups according to the histological severity of gastric mucosal atrophy: the non-atrophic gastritis (NA) group (atrophy score=0 and metaplasia score=0), the severe atrophic gastritis (SA) group (atrophy score>=2 or metaplasia score>=2), and the mild atrophic gastritis (MA) group (all others), synergistic effect was found between numbers of IL-1ß-31C, IL-1ß-511T variant alleles with co-factors on the development of gastric atrophy in the antrum (gender + H. pylori + number of IL-1ß-31C allele: p=0.001, age + gender + H. pylori + number of IL-1ß-31C allele: p=0.0008, gender + H. pylori + number of IL-1ß-511T allele: p=0.016, age + gender + H. pylori + number of IL-1ß-511T allele: p=0.013), while such association was found for TNF-α-857 T allele in the antrum and all genotypes in the corpus. CONCLUSIONS: IL-1ß-31C, IL-1ß-511T variant alleles may accelerate gastric mucosal inflammation and atrophy, not only by themselves, but also through the interaction with co-factors.

Complete omission of second-look endoscopy after gastric endoscopic submucosal dissection in real-world practice.

Gastric endoscopic submucosal dissection (ESD) is increasingly performed in patients receiving antithrombotic therapy. Second-look endoscopy (SLE) has been performed empirically in several clinical settings. We investigated whether SLE omission was associated with an increased risk of postESD bleeding in all patients, including those administered antithrombotic agents. Between July 2016 and June 2018, 229 patients were treated with a clinical pathway for gastric ESD that involved SLE on the day after ESD (SLE group). Between September 2018 and May 2020, 215 patients were treated using a clinical pathway that did not include SLE (nonSLE group). We retrospectively compared the incidence of postESD bleeding among the propensity score-matched cohorts and determined the risk factors for postESD bleeding using multivariate analysis. The propensity score-matched cohorts showed no significant differences in the incidence of postESD bleeding between the SLE (3.2%) and nonSLE (5.1%) groups. Multivariate analysis revealed that the presence of lesions in the lower gastric body (adjusted odds ratio [OR] 2.17, 95% confidence interval [CI] 1.06-4.35, P.03) was a significant risk factor for postESD bleeding during admission, whereas resected specimen size ≥ 40 mm (adjusted OR 3.21, 95% CI 1.19-8.19, P.02) and antiplatelet therapy (adjusted OR 4.16, 95% CI 1.47-11.80, P.007) were significant risk factors after discharge. Complete omission of SLE after gastric ESD does not increase postESD bleeding in clinical practice.

Association study of common genetic variants in pre-microRNAs in patients with ulcerative colitis.

BACKGROUND: Common single-nucleotide polymorphisms (SNPs) in microRNAs (miRNA) have been shown to be associated with susceptibility to several human diseases. We evaluated the associations of three SNPs (rs11614913, rs2910164, and rs3746444) in pre-miRNAs (miR-196a2, miR-146a, and miR-499) with the risk of ulcerative colitis (UC) in a Japanese population. METHODS: The rs11614913 (T > C), rs2910164 (C > G), and rs3746444 (A > G) SNPs were genotyped in 170 UC and 403 control subjects. RESULTS: The rs3746444 AG genotype was significantly higher among the UC group (odds ratio (OR) = 1.51, 95% CI = 1.03-2.21, p = 0.037). The rs3746444 AG genotype was associated with onset at an older age (OR = 1.70, 95% CI = 1.04-2.78, p = 0.035), left-sided colitis and pancolitis (left-sided colitis, OR = 2.10, 95% CI = 1.12-3.94, p = 0.024; pancolitis, OR = 1.81, 95% CI = 1.09-3.01, p = 0.028, left-sided colitis + pancolitis, OR = 1.91, 95% CI = 1.26-2.92, p = 0.003), higher number of times hospitalized (OR = 2.63, 95% CI = 1.22-5.69, p = 0.017), steroid dependence (OR = 2.63, 95% CI = 1.27-5.44, p = 0.014), and refractory phenotypes (OR = 2.76, 95% CI = 1.46-5.21, p = 0.002) while the rs3746444 AA genotype was inversely associated with the number of times hospitalized (2∼, OR = 0.36, 95% CI = 0.17-0.79, p = 0.012), steroid dependence (OR = 0.42, 95% CI = 0.21-0.88, p = 0.021), and refractory phenotypes (OR = 0.38, 95% CI = 0.20-0.72, p = 0.003). The rs1161913 TT genotype also held a significantly higher risk of refractory phenotype (T/T vs. T/C + C/C, OR = 2.21, 95% CI = 1.17-4.18, p = 0.016). CONCLUSIONS: Our results provided the first evidence that rs3746444 SNP may influence the susceptibility to UC, and both rs3746444 and rs11614913 SNPs may influence the pathophysiological features of UC.

Effect of polymorphisms of IL-1ß and TNF-α genes on CpG island hyper methylation (CIHM) in the nonneoplastic gastric mucosa.

CpG island hyper methylation (CIHM) is one of the major events in gastric carcinogenesis. To evaluate the influence of host genetic factors in CIHM related carcinogenesis, we investigated the association between common polymorphisms in IL-1ß and TNF-α genes, with CIHM status in the nonneoplastic gastric mucosa. Polymorphisms in the IL-1ß gene (-31T>C and -511C>T) and the TNF-α gene (-857C>T) were genotyped in 385 cancer-free subjects. CIHM of four candidate genes: p16 (INK4a), p14 (ARF), E-cadherin (CDH1), and death-associated protein kinase (DAP-kinase), were determined by methylation-specific-polymerase chain reaction (MSP). CIHM high was defined as two or more CpG islands methylated. CIHM of all four genes and CIHM high were significantly associated with Helicobacter pylori infection status. In over all, significant marginal association was found between IL-1ß-511 TT genotype and reduced susceptibility to CIHM of DAP-kinase (adjusted OR = 0.48, 95% CI = 0.29-0.78) and CIHM high (adjusted OR = 0.53, 95% CI = 0.32-0.86). This association was more enhanced in subjects 65 yr or younger age. We also found positive association between TNF-α-857T carrier and increased susceptibility to CIHM of CDH (adjusted OR = 1.78, 95% CI = 1.01-3.16), and CIHM high (adjusted OR = 1.86, 95% CI = 1.04-3.33) in the same generation. The mean number of CIHM was lower in subjects with IL-1ß-511TT genotype, while the mean number was higher in subjects with TNF-α-857 T carrier especially in subjects 65 yr and younger patients. IL-1ß-511 TT genotype is associated with reduced susceptibility to CIHM especially in younger generation. Furthermore, the TNF-α-857T carrier is associated with increased susceptibility of CIHM in the same generation.

Polymorphisms of DNA repair and xenobiotic genes predispose to CpG island methylation in non-neoplastic gastric mucosa.

BACKGROUND: Genetic factors, related to DNA repair or xenobiotic pathways might confer different degrees of susceptibility to gastric carcinogenesis. CpG island hyper methylation (CIHM) is a major event in gastric carcinogenesis. We evaluated the association between XRCC1, GSTP1, GSTT1 and GSTM1 polymorphisms with CIHM status in non-neoplastic gastric mucosa. METHODS: XRCC1 Arg399Gln, and Arg194Trp, GSTP1 Ile104Val, and GSTT1, GSTM1 null polymorphisms were genotyped in 415 cancer free subjects, in relation to four candidate CpG (p14, p16, DAP-kinase and CDH1) loci, assessed by Methylation-Specific-Polymerase Chain Reaction (MSP). CIHM high was defined as two or more CpG islands methylated. RESULTS: Significant association between XRCC1 codon 399 Gln/Gln genotype and reduced susceptibility to CIHM of DAP-kinase (adjusted OR = 0.30, 95%CI = 0.13-0.71, p = .0055) and CIHM high (OR = 0.42, 95%CI = 0.19-0.97, p = .04). XRCC1 codon 399 Gin/Gln genotype also presented lower number of CIHM when compared with both Arg/Gln, and Arg/Arg + Arg/Gln genotypes (p = .02, .046, respectively) When subjects were divided according to age (>50 and <50), an association was found between GSTM1 null genotype and increased susceptibility to CIHM high in the 50 years and older generations (OR = 1.63, 95%CI = 1.01-2.62, p = .045). CONCLUSION: XRCC1 codon 399 Gln/Gln genotype is associated with reduced susceptibility to CIHM especially DAP-kinase. GSTM1 null genotype may increase the susceptibility to CIHM especially in older patients. Genetic factors, related to DNA repair or xenobiotic pathways may have a role in CIHM-related gastric carcinogenesis.

Usefulness of transnasal endoscopy where endoscopic submucosal dissection is difficult.

BACKGROUND: Early gastric cancer located from the pyloric ring to inside the duodenal bulb (DB) is not easily treated by endoscopic submucosal dissection (ESD). The endoscope needs to be reversed inside the DB to set the resection line at a safe distance from the anal side. Because of the space limitations and limited flexibility of conventional endoscopy (CE), there have been increasing possibilities of complications. Here we report a new ESD technique using a transnasal endoscope (TN-E) that is reversed inside the DB. METHODS: The subjects were 5 patients with early gastric cancer or adenoma, at locations ranging from the pyloric ring to inside the DB, who were all treated by ESD. We compared results in these patients (TN-E group) with results in five patients with similar disease characteristics who were treated by ESD before July 2008, when the TN-E treatment method was introduced (CE group). In the TN-E group, after marking by CE, we switched the endoscope to the TN-E, and performed the reversing procedure inside the DB, and cut the anal side of the lesion in a semicircle. We switched back to CE to dissect the remaining half on the oral side. We compared the average resection time, en-bloc resection rate, and safety margin between the TN-E and CE groups. RESULTS: Reversing inside the DB and the anal-side procedures proved easy and there were no complications. No bleeding or perforation occurred. The average resection times and en-bloc resection rates were not different between the two groups. All the resections by the TN-E were more than 5 mm away from the tumor margin, whereas a resection rate with a safety margin of more than 5 mm was 80% by CE. CONCLUSIONS: In conclusion, the TN-E was safe and effective for use inside the DB. ESD using the TN-E contributed to accurate pathological diagnosis, because the size of the resected specimen was sufficient to prevent the burning effect caused by the ESD.

Usefulness of magnifying narrow-band imaging endoscopy in the Helicobacter pylori-related chronic gastritis.

Combining the narrow-band imaging (NBI) system and magnifying endoscopy allows simple and clear visualization of microscopic structures of the superficial mucosa and its capillary patterns, which may be useful for precise endoscopic diagnosis in the gastrointestinal tract, being more closely to histopathological diagnosis. In the non-neoplastic gastric mucosa, there have been reports showing a potential usefulness of magnifying NBI for the diagnosis of Helicobacter pylori infection, degree of histological gastritis, and intestinal metaplasia. We have shown that magnifying NBI appearances in the non-neoplastic gastric mucosa also predicts pepsinogen levels, which indicates extension of gastric atrophy in the entire stomach, and gastric cancer occurrence. Furthermore, we have shown that magnifying NBI appearances predicts the result of H. pylori treatment. Clear visualization of fine mucosal and capillary patterns, obtained by magnifying NBI, allows prediction of the histological condition, more in detail without biopsy, and it may also be useful for less invasive, and cost-effective endoscopic gastric cancer surveillance, and prediction of H. pylori eradication.