Federico Sopena

Gastric Cancer Susceptibility Is Not Linked to Pro- and Anti-Inflammatory Cytokine Gene Polymorphisms in Whites: A Nationwide Multicenter Study in Spain

BACKGROUND AND AIMS:Recent studies have reported an association between cytokine gene polymorphisms and GC risk. However, results are inconsistent among studies from different geographic regions and ethnic groups. Our goal was to evaluate the influence of Helicobacter pylori (H. pylori) infection and host genetic factors on GC susceptibility in a population of Spanish white GC patients.METHODS: DNA from 404 unrelated patients with GC and 404 sex- and age-matched healthy controls was typed for several functional polymorphisms in pro- (IL-1B, TNFA, LTA, IL-12p40) and anti-inflammatory (IL-4, IL-1RN, IL-10, TGFB1) genes by PCR, RFLP, and TaqMan assays. H. pylori infection and CagA/VacA antibody status were also determined by western blot serology.RESULTS: Logistic regression analysis identified H. pylori infection with cagA strains (OR 2.54, 95% CI 1.77–3.66), smoking habit (OR 1.91, 95% CI 1.25–2.93), and positive family history of GC (OR 3.67, 95% CI 2.01–6.71) as independent risk factors for GC. None of the cytokine gene polymorphisms analyzed in this study were associated with susceptibility to GC development, whether GC patients were analyzed as a group or categorized according to anatomic location or histological subtype. Some simultaneous combinations of proinflammatory genotypes reportedly associated with greater GC risk yielded no significant differences between patients and controls.CONCLUSIONS: Our results show that, at least in some white populations, the contribution of the cytokine gene polymorphisms evaluated in this study (IL-1B, IL-1RN, IL-12p40, LTA, IL-10, IL-4, and TGF-B1) to GC susceptibility may be less relevant than previously reported.

Relevance of GSTM1, GSTT1, and GSTP1 gene polymorphisms to gastric cancer susceptibility and phenotype

Human glutathione S-transferases (GSTs) are phase II metabolizing enzymes that play a key role in protecting against cancer by detoxifying numerous potentially cytotoxic/genotoxic compounds. The genes encoding the human GST isoenzymes GSTM(mu)1, GSTT(theta)1 and GSTP(pi)1 harbour polymorphisms, which have been considered important modifiers of the individual risk for environmentally induced cancers such as gastric cancer (GC). However, results are inconsistent among studies from different geographic areas and ethnic groups. Our goal was to perform a nationwide, case-control study in Spain to evaluate the relevance of several functional GST gene polymorphisms and environmental factors to GC risk and phenotype. DNA from 557 GC patients and 557 sex- and age-matched healthy controls (HC) was typed for two deletions in the GSTM1 and GSTT1 genes and two SNPs in the GSTP1 gene (rs1695 and rs1138272) using polymerase chain reaction-restriction fragment length polymorphism methods. Logistic regression analysis identified Helicobacter pylori infection with CagA strains [odds ratio (OR): 2.36; 95% confidence interval (CI): 1.78-3.15], smoking habit (OR: 2.10; 95% CI: 1.48-2.97) and family history of GC (OR: 3.2; 95% CI: 2.02-5.16) as independent risk factors for GC. No differences in the frequencies of GSTM1 or GSTT1 null genotypes were observed between cases and controls (GSTM1: 50.8% vs. 48%; GSTT1: 21.5% vs. 21%). Moreover, simultaneous carriage of both, the GSTM1 and the GSTT1 null genotypes, was almost identical in both groups (10.7% in GC vs. 10.6% in HC). In addition, no significant differences in GSTP1 Ile105Val (rs1695) and GSTP1 Val114Ala (rs1138272) genotype distribution were observed between GC patients and controls. Subgroup analysis for age, gender, Helicobacter pylori status, smoking habits, family history of GC, anatomic location and histological subtype revealed no significant association between GST variants and GC risk. Our results show that the GST polymorphisms evaluated in this study are not relevant when determining the individual susceptibility to GC or phenotype in a South-European population.

CagA-positive Helicobacter pylori infection is not associated with decreased risk of Barrett's esophagus in a population with high H. pylori infection rate

Background & aimThe role that H. pylori infection plays in the development of and Barretts esophagus (BE) is uncertain. We tested the hypothesis that infection with cagA+ Helicobacter pylori strains protects against the development of BE.MethodsWe studied 104 consecutive patients, residents in an area with a high prevalence of H. pylori infection, with BE and 213 sex- and age-matched controls. H. pylori infection and CagA antibody status were determined by western blot serology.ResultsH. pylori prevalence was higher in patients with BE than in controls (87.5% vs. 74.6%; OR. 2.3; 95% CI: 1.23–4.59). Increasing age was associated with a higher prevalence of H. pylori (p < 0.05). The prevalence of CagA+ H. pylori serology was similar in patients with BE and controls (64.4% vs. 54.5%; NS). Type I H. pylori infection (CagA+ and VacA+) was similar in patients with BE and controls (44.2% vs. 41.3%; NS). Logistic regression analysis identified alcohol (O.R. 7.09; 95% CI 2.23–22.51), and H. pylori infection (OR: 2.41; 95%CI: 1.20–4.84) but not CagA+ serology as independent factors.ConclusionNeither H. pylori infection nor H. pylori infection by CagA+ strains reduce the risk of BE in a population with high prevalence of H. pylori infection.

Identification of the tumour transition states occurring during EMT

In cancer, the epithelial-to-mesenchymal transition (EMT) is associated with tumour stemness, metastasis and resistance to therapy. It has recently been proposed that, rather than being a binary process, EMT occurs through distinct intermediate states. However, there is no direct in vivo evidence for this idea. Here we screen a large panel of cell surface markers in skin and mammary primary tumours, and identify the existence of multiple tumour subpopulations associated with different EMT stages: from epithelial to completely mesenchymal states, passing through intermediate hybrid states. Although all EMT subpopulations presented similar tumour-propagating cell capacity, they displayed differences in cellular plasticity, invasiveness and metastatic potential. Their transcriptional and epigenetic landscapes identify the underlying gene regulatory networks, transcription factors and signalling pathways that control these different EMT transition states. Finally, these tumour subpopulations are localized in different niches that differentially regulate EMT transition states.Epithelial-to-mesenchymal transition in tumour cells occurs through distinct intermediate states, associated with different metastatic potential, cellular properties, gene expression, and chromatin landscape

Relevance of IL-1 and TNF gene polymorphisms on interleukin-1β and tumor necrosis factor-α gastric mucosal production

We aimed to evaluate the influence of Helicobacter pylori infection and IL-1/TNF gene polymorphisms on interleukin (IL)-1beta and tumor necrosis factor (TNF)-alpha gastric mucosal production. IL-1beta and TNF-alpha levels in homogenized biopsy specimens taken from the antrum and corpus of 81 patients were measured by enzyme-linked immunosorbent assay. Genomic DNA was typed for the IL1B-511, IL1B+3954, variable number of tandem repeat (VNTR) IL1RN, TNFA-308, TNFA-238, LTA NcoI, and LTA Bsi gene polymorphisms by polymerase chain reaction, restriction fragment length polymorphism, and TaqMan assays. H. pylori infection and CagA/VacA antibody status were determined by Western blot. IL-1beta and TNF-alpha protein levels were significantly higher in the gastric antrum of patients infected with H. pylori compared with uninfected patients [9.54 (5.07-16.28) vs. 4.55 (3.69-8.28) pg IL-1beta/mg protein, p = 0.004, and 1.5 (0.7-2.71) vs. 0.63 (0.3-1.26) pg TNF-alpha/mg protein, p = 0.001]. Among H. pylori-infected individuals, carriers of the IL1RN*2 allele had significantly higher antrum mucosal IL-1beta levels than noncarriers [15.97 (9.59-26.6) vs. 10.08 (7.72-13.33), p = 0.008]. No association between gastric mucosal TNF-alpha levels and genotypes of the TNFA and LTA gene polymorphisms was reported. Our results indicate that the VNTR polymorphism of the IL1RN gene influences IL-1beta gastric mucosal production in patients infected with H. pylori.

Association of PSCA rs2294008 gene variants with poor prognosis and increased susceptibility to gastric cancer and decreased risk of duodenal ulcer disease.

Two recent genome‐wide association studies in Asians have reported the association between the PSCA (prostate stem cell antigen) rs2294008C>T gene polymorphism and two Helicobacter pylori infection‐related diseases such as gastric cancer (GC) and duodenal ulcer (DU). Since rs2294008 allele frequencies differ notably among ethnicities, we aimed to assess the role of rs2294008 on the susceptibility to GC and DU in a Caucasian population in Spain. Moreover, the relevance of rs2294008 on GC prognosis was evaluated. Genomic DNA from 603 Spanish patients with primary GC, 139 with DU and 675 healthy controls was typed for the PSCA rs2294008C>T polymorphism by PCR‐TaqMan assays. H. pylori infection [odds ratio (OR): 8.27; 95% confidence interval (CI): 3.45–15.33] and nonsteroidal anti‐inflammatory drugs (OR: 6.54; 95% CI: 3.19–12.43) were identified as independent risk factors for DU whereas the rs2294008T allele was associated with reduced risk of developing the disease (OR: 0.52; 95% CI: 0.33–0.82). Infection with CagA strains (OR: 2.10; 95% CI: 1.63–2.34), smoking (OR: 1.93; 95% CI: 1.54–2.61), family history of GC (OR: 2.83; 95% CI: 2.01–3.83), and the rs2294008T allele (OR: 1.46; 95% CI: 1.07–1.99) were associated with increased risk of GC. Interestingly, the association with the rs2294008T allele was restricted to noncardia GC (OR: 1.43; 95% CI: 1.12–1.82), particularly of the diffuse histotype (OR: 1.59; 95% CI: 1.16–1.92). Finally, Cox regression analysis identified the rs2294008T variant as a prognosis factor associated with worse overall survival in patients with diffuse‐type GC (hazard ratio: 1.85; 95% CI: 1.12–3.06). From these results we conclude that the PSCA rs2294008 polymorphism is involved in the susceptibility to GC and DU, as well as in the prognosis of the diffuse‐type of GC in Caucasians.

Prognostic Role of Host Cyclooxygenase and Cytokine Genotypes in a Caucasian Cohort of Patients with Gastric Adenocarcinoma

Background Genetic factors influencing the prognosis of gastric adenocarcinoma (GAC) are not well known. Given the relevance of cytokines and other pro-inflammatory mediators in cancer progression and invasiveness, we aimed to assess the prognostic role of several functional cytokine and cyclooxygenase gene polymorphisms in patients with GAC. Methodology Genomic DNA from 380 Spanish Caucasian patients with primary GAC was genotyped for 23 polymorphisms in pro-inflammatory (IL1B, TNFA, LTA, IL6, IL12p40), anti-inflammatory (IL4, IL1RN, IL10, TGFB1) cytokine, and cyclooxygenase (PTGS1 and PTGS2) genes by PCR, RFLP and TaqMan assays. Clinical and histological information was collected prospectively. Survival curves were estimated by the Kaplan-Meier method and compared using the log rank test. Outcome was determined by analysis of Cox proportional hazards, adjusting for confounding factors. Results The median follow-up period and median overall survival (OS) time were 9.9 months (range 0.4–120.3) and 10.9 months (95% CI: 8.9–14.1), respectively. Multivariate analysis identified tumor stages III (HR, 3.23; 95% CI:2–5.22) and IV (HR, 5.5; 95% CI: 3.51–8.63) as independent factors associated with a significantly reduced OS, whereas surgical treatment (HR: 0.44; 95%CI: 0.3–0.6) was related to a better prognosis of the disease. Concerning genetic factors, none of the 23 polymorphisms evaluated in the current study did influence survival. Moreover, no gene-environment interactions on GAC prognosis were observed. Conclusions Our results show that, in our population, the panel of selected pro- and anti-inflammatory cytokine, and cyclooxygenase gene polymorphisms are not relevant in determining the prognosis of gastric adenocarcinoma.

Esophageal motility and intraesophageal pH patterns in patients with esophagitis and chronic nonsteroidal anti-inflammatory drug use.

Clinical reports suggest that nonsteroidal anti-inflammatory drugs (NSAIDs) use might induce esophageal symptoms and damage, including esophagitis, but experimental data are conflicting, and some indicate that NSAIDs improve mucosal damage. It is not known whether patients with endoscopically diagnosed esophagitis during NSAID use have different baseline reflux patterns from patients with reflux esophagitis and no NSAID use. Two groups of patients with and without chronic NSAID use and esophagitis were prospectively studied. Twenty-four-hour pH monitoring and esophageal manometry were performed in all patients who were free of NSAID and any other drug use during tests. Esophageal motility and reflux patterns did not differ in patients with esophagitis regardless of the presence or absence of NSAID use. However, the subgroup of patients with grades II and III esophagitis and chronic NSAID use had a significantly greater lower esophageal sphincter (LES) pressure and a less severe intraesophageal pH profile than patients without NSAID use. In agreement with clinical reports, these results suggest that NSAID use may aggravate an otherwise milder acid-related esophageal disease in a subgroup of patients.

Relevance of DNA repair gene polymorphisms to gastric cancer risk and phenotype

Variations in DNA repair genes have been reported as key factors in gastric cancer (GC) susceptibility but results among studies are inconsistent. We aimed to assess the relevance of DNA repair gene polymorphisms and environmental factors to GC risk and phenotype in a Caucasian population in Spain. Genomic DNA from 603 patients with primary GC and 603 healthy controls was typed for 123 single nucleotide polymorphisms in DNA repair genes using the Illumina platform. Helicobacter pylori infection with CagA strains (odds ratio (OR): 1.99; 95% confidence interval (CI): 1.55–2.54), tobacco smoking (OR: 1.77; 95% CI: 1.22–2.57), and family history of GC (OR: 2.87; 95% CI: 1.85–4.45) were identified as independent risk factors for GC. By contrast, the TP53 rs9894946A (OR: 0.73; 95% CI: 0.56–0.96), TP53 rs1042522C (OR: 0.76; 95% CI: 0.56–0.96), and BRIP1 rs4986764T (OR: 0.55; 95% CI: 0.38–0.78) variants were associated with lower GC risk. Significant associations with specific anatomopathological GC subtypes were also observed, most notably in the ERCC4 gene with the rs1799801C, rs2238463G, and rs3136038T variants being inversely associated with cardia GC risk. Moreover, the XRCC3 rs861528 allele A was significantly increased in the patient subgroup with diffuse GC (OR: 1.75; 95% CI: 1.30–2.37). Our data show that specific TP53, BRIP1, ERCC4, and XRCC3 polymorphisms are relevant in susceptibility to GC risk and specific subtypes in Caucasians.

Evidence for PTGER4,PSCA, and MBOAT7 as risk genes for gastric cancer on the genome and transcriptome level

Genetic associations between variants on chromosome 5p13 and 8q24 and gastric cancer (GC) have been previously reported in the Asian population. We aimed to replicate these findings and to characterize the associations at the genome and transcriptome level. We performed a fine‐mapping association study in 1926 GC patients and 2012 controls of European descent using high dense SNP marker sets on both chromosomal regions. Next, we performed expression quantitative trait locus (eQTL) analyses using gastric transcriptome data from 143 individuals focusing on the GC associated variants. On chromosome 5p13 the strongest association was observed at rs6872282 (P = 2.53 × 10−04) and on chromosome 8q24 at rs2585176 (P = 1.09 × 10−09). On chromosome 5p13 we found cis‐eQTL effects with an upregulation of PTGER4 expression in GC risk allele carrier (P = 9.27 × 10−11). On chromosome 8q24 we observed cis‐eQTL effects with an upregulation of PSCA expression in GC risk allele carrier (P = 2.17 × 10−47). In addition, we found trans‐eQTL effects for the same variants on 8q24 with a downregulation of MBOAT7 expression in GC risk allele carrier (P = 3.11 × 10−09). In summary, we confirmed and refined the previously reported GC associations at both chromosomal regions. Our data point to shared etiological factors between Asians and Europeans. Furthermore, our data imply an upregulated expression of PTGER4 and PSCA as well as a downregulated expression of MBOAT7 in gastric tissue as risk‐conferring GC pathomechanisms.