Effect of various noise sources on the detective quantum efficiency of phosphor screens

Association between interleukin 10 (IL-10) polymorphisms and leishmaniasis progression: a systematic review and meta-analysis

Interleukin 10 (IL-10) is associated with the progression of leishmaniasis because it inhibits the leishmanicidal action of macrophages and the production of mediators such as IFN-γ and nitric oxide. Studies have shown that specific polymorphisms are associated with the regulatory role of IL-10 and the development of more relevant clinical forms of leishamaniasis. We performed a systematic review and meta-analysis to determine whether single nucleotide polymorphisms (SNPs) of IL-10 influence the progression of leishmaniasis. The selected articles were read in full and only those consistent with the eligibility criteria were included in our study. Seven studies were eligible according to the inclusion criteria and were included in the present systematic review, but only five were subjected to statistical analysis. The pooled odds ratios showed no significant association between the rs1800871 SNP and the progression of leishmaniasis in all genotype models, including the dominant, recessive, homozygote, heterozygote, and allelic models. Regarding the association between rs1800896 SNP and the progression of leishmaniasis, the pooled odds ratios showed no association under all genotype models. Hence, IL-10 SNPs did not show significant association and were not considered a risk factor for the progression of leishmaniasis.

Immune response to Helicobacter pylori infection and gastric cancer development

Gastric adenocarcinoma is a global health concern, and Helicobacter pylori (H. pylori) infection is the main risk factor for its occurrence. Of note, the immune response against the pathogen seems to be a determining factor for gastric oncogenesis, and increasing evidence have emphasized several host and bacterium factors that probably influence in this setting. The development of an inflammatory process against H. pylori involves a wide range of mechanisms such as the activation of pattern recognition receptors and intracellular pathways resulting in the production of proinflammatory cytokines by gastric epithelial cells. This process culminates in the establishment of distinct immune response profiles that result from the cytokine-induced differentiation of T naïve cells into specific T helper cells. Cytokines released from each type of T helper cell orchestrate the immune system and interfere in the development of gastric cancer in idiosyncratic ways. Moreover, variants in genes such as single nucleotide polymorphisms have been associated with variable predispositions for the occurrence of gastric malignancy because they influence both the intensity of gene expression and the affinity of the resultant molecule with its receptor. In addition, various repercussions related to some H. pylori virulence factors seem to substantially influence the host immune response against the infection, and many of them have been associated with gastric tumorigenesis.

MicroRNA-1224 Inhibits Tumor Metastasis in Intestinal-Type Gastric Cancer by Directly Targeting FAK

Intestinal-type gastric cancer (GC) of the Lauren classification system has specific epidemiological characteristics and carcinogenesis patterns. MicroRNAs (miRNAs) have prognostic significance, and some can be used as prognostic biomarkers in GC. In this study, we identified miR-1224 as a potential survival-related miRNA in intestinal-type GC patients by The Cancer Genome Atlas (TCGA) analysis. Using quantitative real-time PCR (qRT-PCR), we showed that the relative expression of miR-1224 was significantly decreased in intestinal-type GC tissues compared to matched adjacent normal mucosa tissues (p < 0.01). We found that high miR-1224 expression was associated with no lymph-node metastasis (p < 0.05) and good prognosis (p = 0.028) in 90 intestinal-type GC tissues. Transfection of intestinal-type GC cells with miR-1224 mimics showed that miR-1224 suppressed cell migration in vitro (wound healing assay and Transwell migration assay), whereas the transfection of cells with miR-1224 inhibitor promoted cell migration in vitro. miR-1224 also suppressed intestinal-type GC cell metastasis in a xenograft mouse model. Furthermore, bioinformatics, luciferase reporter, Western blotting, and immunohistochemistry (IHC) studies demonstrated that miR-1224 directly bound to the focal adhesion kinase (FAK) gene, and downregulated its expression, which decreased STAT3 and NF-κB signaling and subsequent the epithelial-to-mesenchymal transition (EMT). Repression of FAK is required for the miR-1224-mediated inhibition of cell migration in intestinal-type GC. The present study demonstrated that miR-1224 is downregulated in intestinal-type GC. miR-1224 inhibits the metastasis of intestinal-type GC by suppressing FAK-mediated activation of the STAT3 and NF-κB pathways, and subsequent EMT. miR-1224 could represent an important prognostic factor in intestinal-type GC.

Association of host immunity with Helicobacter pylori infection in recurrent gastric cancer

Background

Helicobacter pylori infection is associated with the incidence of gastric cancer. Endoscopic resection has been developed as a proper technique to treat early stage of gastric cancer. However, some patients develop recurrent gastric cancer within 5 years after endoscopic treatment. The aim of the present study is to explore a biomarker for detecting people who has high risk of gastric cancer recurrence.

Methods

We analyzed the Interleukin-10 (IL-10) single nucleotide polymorphism (SNP) and IgG subclass responses to the bacteria in patients with early gastric cancer and recurrent gastric cancer.

Results

Patients with hetero-type in the 1082 SNP and CC genotype in the 592 SNP were at high risk of recurrence of gastric cancer. In patients with genotype carrying high risk of recurrence, IgG1 level tended to be higher than that in patients with other genotypes.

Conclusions

Dominance of T helper 2 (Th2) immunity controlled by IL-10 cytokine may be associated with H. pylori-associated gastric cancer recurrence.

Genetic Polymorphisms in Inflammatory and Other Regulators in Gastric Cancer: Risks and Clinical Consequences

Helicobacter pylori infection is associated with the development of a chronic inflammatory response, which may induce peptic ulcers, gastric cancer (GC), and mucosa-associated lymphoid tissue (MALT) lymphoma. Chronic H. pylori infection promotes the genetic instability of gastric epithelial cells and interferes with the DNA repair systems in host cells. Colonization of the stomach with H. pylori is an important cause of non-cardia GC and gastric MALT lymphoma. The reduction of GC development in patients who underwent anti-H. pylori eradication schemes has also been well described. Individual susceptibility to GC development depends on the host's genetic predisposition, H. pylori virulence factors, environmental conditions, and geographical determinants. Biological determinants are urgently sought to predict the clinical course of infection in individuals with confirmed H. pylori infection. Possible candidates for such biomarkers include genetic aberrations such as single-nucleotide polymorphisms (SNPs) found in various cytokines/growth factors (e.g., IL-1β, IL-2, IL-6, IL-8, IL-10, IL-13, IL-17A/B, IFN-γ, TNF, TGF-β) and their receptors (IL-RN, TGFR), innate immunity receptors (TLR2, TLR4, CD14, NOD1, NOD2), enzymes involved in signal transduction cascades (PLCE1, PKLR, PRKAA1) as well as glycoproteins (MUC1, PSCA), and DNA repair enzymes (ERCC2, XRCC1, XRCC3). Bacterial determinants related to GC development include infection with CagA-positive (particularly with a high number of EPIYA-C phosphorylation motifs) and VacA-positive isolates (in particular s1/m1 allele strains). The combined genotyping of bacterial and host determinants suggests that the accumulation of polymorphisms favoring host and bacterial features increases the risk for precancerous and cancerous lesions in patients.

Preliminary analysis of single-nucleotide polymorphisms in IL-10, IL-4, and IL-4Rα genes and profile of circulating cytokines in patients with gastric Cancer

Background

Gastric Cancer is highly prevalent and deadly worldwide. In Colombia, it is the most lethal form of cancer. Some single-nucleotide polymorphisms in IL-10, IL-4, and IL-4Rα genes have been associated with an anti-inflammatory environment and a Th2 profile in detriment of the antitumor Th1 response. This research sought to detect single-nucleotide polymorphisms in promoter sequences, like − 1082 (G/A), − 592 (C/A), and − 819 (C/T), as well as − 590 (C/T) of the IL-10 and IL-4 genes, respectively; in addition to the IL-4Rα mutation variants, Ile50Val and Q576R, together with circulating levels of IL-4, TNF-α, IL-10, and IFN-γ in patients with gastric carcinoma in Cúcuta, Colombia.

Methods

In a cross-sectional study, 17 patients and 30 healthy individuals were genotyped for the six polymorphisms mentioned through PCR-RFLP of DNA obtained from peripheral blood cells and serum samples were analyzed by sandwich ELISA to quantify cytokines. Statistical difference between groups was determined along with the association between the presence of polymorphisms and the risk of gastric cancer, as well as the mortality in patients, using Mann-Whitney U test and logistic regression analysis, respectively.

Results

An association between the − 1082 (G/A) and the risk of gastric cancer was found (OR = 7.58, range 0.77–74.06, P = 0.08). Furthermore, patients had a significant increase in IL-4 serum levels (P < 0.01) compared to healthy individuals, both variables showed a higher estimated risk of mortality in patients, although without statistical association (P > 0.05).

Conclusion

We infer that two possible biomarkers (one immunological and one genetic) could be considered in association with gastric cancer in our population, which should be confirmed by subsequent studies involving a greater number of individuals.

Association of IL10 gene promoter polymorphisms with risks of gastric cancer and atrophic gastritis

OBJECTIVE

To investigate the association between polymorphisms of the interleukin 10 ( IL10) gene and risk of gastric cancer (GC) and atrophic gastritis (AG).

METHODS

This study enrolled patients with GC, patients with AG and healthy control subjects. Demographic data were collected and the IL10 gene -1082A/G, -819C/T and -592A/C polymorphisms were genotyped. An enzyme-linked immunosorbent assay was performed to detect Helicobacter pylori infection.

RESULTS

The study enrolled 556 participants including 208 in the GC group, 116 in the AG group and 232 controls (CON group). In a recessive model of the IL10-819C/T polymorphism, a significantly decreased risk of GC was found compared with AG and non-cancer subjects, respectively (AG→GC: odds ratio OR 0.41; non-cancer→GC: OR 0.57). The CC genotype demonstrated a significantly increased risk of AG compared with CON. Similar significant results were detected in males and H. pylori-negative subgroups. The ACC haplotype was associated with a decreased risk of GC compared with AG. The ATC haplotype was associated with a decreased risk of AG compared with the CON group, but it was associated with an increased risk of GC compared with AG.

CONCLUSION

The IL10 gene promoter -819C/T (rs1800871) polymorphism was associated with the risk of GC and AG in a Chinese population.

ASSOCIATION OF INTERLEUKIN-10 -1082 A/G (RS1800896) POLYMORPHISM WITH SUSCEPTIBILITY TO GASTRIC CANCER: META-ANALYSIS OF 6,101 CASES AND 8,557 CONTROLS

BACKGROUND

The promoter -1082 A/G (rs1800896) polymorphism of Interleukin-10 (IL-10) gene have been widely reported and considered to have a significant role on gastric cancer risk, but the results are inconsistent.

OBJECTIVE

To clarify the association, we conducted a meta-analysis to investigate the associations IL-10 -1082 A/G polymorphism with gastric cancer.

METHODS

Eligible articles were identified by searching databases including PubMed, Web of Science, and Google Scholar up to August 03, 2017. Odds ratios (OR) with corresponding 95% confidence intervals (CIs) were used to assess the association.

RESULTS

A total of 30 case-control studies with 6,101 cases and 8,557 controls were included in this meta-analysis. Overall, a significant association between IL-10 -1082 A/G polymorphism and gastric cancer risk was observed under the allele model (G vs A: OR=1.305, 95% CI=1.076-1.584; P=0.007), heterozygote model and (GA vs AA: OR=1.252, 95% CI=1.252-1.054; P=0.011) and dominant model (GG+GA vs AA: OR=1.264, 95% CI=1.053-1.516; P=0.012). In the subgroup analysis by ethnicity, increased gastric cancer risk were found in Asians under the allele model (G vs A: OR=1.520, 95% CI=1.172-1.973; P=0.002), homozygote model (GG+GA vs AA: OR=1.571, 95% CI=1.023-2.414; P= 0.039), heterozygote model (GA vs AA: OR=1.465, 95% CI=1.192-1.801; P≤0.001) and dominant model (GG+GA vs AA: OR=1.448, 95% CI=1.152-1.821; P=0.002), but not among Caucasian and Latinos populations.

CONCLUSION

These results suggested that the IL-10 -1082 A/G (rs1800896) polymorphism might contribute to the gastric cancer susceptibility, especially among Asians.

Interleukin 10 gene rs1800896 polymorphism is associated with the risk of prostate cancer

Numerous studies have uncovered the association of Interleukin-10 (IL-10) gene rs1800896 polymorphism with the risk of prostate cancer (PCa); however, their conclusions were inconsistent. Therefore, we conducted this meta-analysis to evaluate the role of IL-10 rs1800896 polymorphism in the risk of PCa. 16 eligible studies in 15 articles involving 6,301 cases and 6,510 controls were identified by researching PubMed, Google, CNKI, and EMBASE up to April 1, 2017. Our results revealed that IL-10 rs1800896 polymorphism was associated with the decreased risk of PCa under the homozygous model. Subgroup analysis by ethnicity revealed that rs1800896 polymorphism decreased the risk of PCa among Caucasians. In conclusion, IL-10 gene rs1800896 polymorphism is associated with the decreased risk of PCa. Larger studies with more diverse ethnic populations are needed to confirm these results.

Inflammatory breast cancer: High incidence of GCC haplotypes (−1082A/G, −819T/C, and −592A/C) in the interleukin-10 gene promoter correlates with over-expression of interleukin-10 in patients’ carcinoma tissues

Interleukin-10 is involved in carcinogenesis by supporting tumor escape from the immune response. The aim of this study was to assess the single nucleotide polymorphisms, −1082A/G, −819T/C and −592A/C, in interleukin-10 gene promoter in inflammatory breast cancer compared to non–inflammatory breast cancer and association of these polymorphisms with interleukin-10 gene expression. We enrolled 105 breast cancer tissue (72 non–inflammatory breast cancer and 33 inflammatory breast cancer) patients and we determined the three studied single nucleotide polymorphisms in all samples by polymerase chain reaction restriction fragment length polymorphism and investigated their association with the disease and with various prognostic factors. In addition, we assessed the expression of interleukin-10 gene by real-time quantitative reverse transcription polymerase chain reaction and the correlation between studied single nucleotide polymorphisms and interleukin-10 messenger RNA expression. We found co-dominant effect as the best inheritance model (in the three studied single nucleotide polymorphisms in non–inflammatory breast cancer and inflammatory breast cancer samples), and we didn’t identify any association between single nucleotide polymorphisms genotypes and breast cancer prognostic factors. However, GCC haplotype was found highly associated with inflammatory breast cancer risk (p < 0.001, odds ratio = 43.05). Moreover, the expression of interleukin-10 messenger RNA was significantly higher (p < 0.001) by 5.28-fold and 8.95-fold than non–inflammatory breast cancer and healthy control, respectively, where GCC haplotype significantly increased interleukin-10 gene expression (r = 0.9, p < 0.001).

Host pathogen interactions in Helicobacter pylori related gastric cancer

Helicobacter pylori (H. pylori), discovered in 1982, is a microaerophilic, spiral-shaped gram-negative bacterium that is able to colonize the human stomach. Nearly half of the world's population is infected by this pathogen. Its ability to induce gastritis, peptic ulcers, gastric cancer and mucosa-associated lymphoid tissue lymphoma has been confirmed. The susceptibility of an individual to these clinical outcomes is multifactorial and depends on H. pylori virulence, environmental factors, the genetic susceptibility of the host and the reactivity of the host immune system. Despite the host immune response, H. pylori infection can be difficult to eradicate. H. pylori is categorized as a group I carcinogen since this bacterium is responsible for the highest rate of cancer-related deaths worldwide. Early detection of cancer can be lifesaving. The 5-year survival rate for gastric cancer patients diagnosed in the early stages is nearly 90%. Gastric cancer is asymptomatic in the early stages but always progresses over time and begins to cause symptoms when untreated. In 97% of stomach cancer cases, cancer cells metastasize to other organs. H. pylori infection is responsible for nearly 60% of the intestinal-type gastric cancer cases but also influences the development of diffuse gastric cancer. The host genetic susceptibility depends on polymorphisms of genes involved in H. pylori-related inflammation and the cytokine response of gastric epithelial and immune cells. H. pylori strains differ in their ability to induce a deleterious inflammatory response. H. pylori-driven cytokines accelerate the inflammatory response and promote malignancy. Chronic H. pylori infection induces genetic instability in gastric epithelial cells and affects the DNA damage repair systems. Therefore, H. pylori infection should always be considered a pro-cancerous factor.

A Causal Role of Genetically Elevated Circulating Interleukin-10 in the Development of Digestive Cancers: Evidence from Mendelian Randomization Analysis Based on 29,307 Subjects

Recent studies have observed a high level of circulating interleukin-10 (IL-10) in patients with digestive cancers, yet whether elevated IL-10 is causally associated with digestive cancers so far remained unresolved. We therefore meta-analyzed available observational studies with Mendelian randomization method to explore this causal association by employing IL-10 gene 3 variants (-592C>A, -819C>T, and -1082A>G) as instruments. Data were available from 52 articles encompassing 29,307 subjects. Subgroup analysis by cancer type indicated that -1082A>G was associated with increased risk of gastric cancer (odds ratio [OR] = 1.19; 95% confidence interval [CI]: 1.05-1.35; P = 0.006), and the association was reinforced for intestinal type gastric cancer (OR = 1.26; 95%CI: 1.09-1.44; P = 0.001). By ethnicity, risk estimate for -1082G allele carriers was increased by 21% for digestive cancers in East Asians (95%CI: 1.05-1.40; P = 0.009). As for the genotype-phenotype association, carriers of -1082G allele had an overall 20.21 pg/mL higher IL-10 level than those with -1082AA genotype (P = 0.023). In further Mendelian randomization analysis, the predicted OR for 10 pg/mL increment in IL-10 was 1.14 (95%CI: 1.01-16.99) in gastric cancer. Our findings provided evidence for a causal role of genetically elevated IL-10 in the development of gastric cancer, especially in East Asians and for intestinal type gastric cancer.

Helicobacter pylori infection and gastric carcinoma: Not all the strains and patients are alike

Gastric carcinoma (GC) develops in only 1%-3% of Helicobacter pylori (H. pylori) infected people. The role in GC formation of the bacterial genotypes, gene polymorphisms and host's factors may therefore be important. The risk of GC is enhanced when individuals are infected by strains expressing the oncoprotein CagA, in particular if CagA has a high number of repeats containing the EPIYA sequence in its C'-terminal variable region or particular amino acid sequences flank the EPIYA motifs. H. pylori infection triggers an inflammatory response characterised by an increased secretion of some chemokines by immunocytes and colonised gastric epithelial cells; these molecules are especially constituted by proteins composing the interleukin-1beta (IL-1β) group and tumour necrosis factor-alpha (TNF-α). Polymorphisms in the promoter regions of genes encoding these molecules, could account for high concentrations of IL-1β and TNF-α in the gastric mucosa, which may cause hypochlorhydria and eventually GC. Inconsistent results have been attained with other haplotypes of inflammatory and anti-inflammatory cytokines. Genomic mechanisms of GC development are mainly based on chromosomal or microsatellite instability (MSI) and deregulation of signalling transduction pathways. H. pylori infection may induce DNA instability and breaks of double-strand DNA in gastric mucocytes. Different H. pylori strains seem to differently increase the risk of cancer development run by the host. Certain H. pylori genotypes (such as the cagA positive) induce high degrees of chronic inflammation and determine an increase of mutagenesis rate, oxidative-stress, mismatch repair mechanisms, down-regulation of base excision and genetic instability, as well as generation of reactive oxygen species that modulate apoptosis; these phenomena may end to trigger or concur to GC development.

Association between pro-(IL-8) and anti-inflammatory (IL-10) cytokine variants and their serum levels and H. pylori-related gastric carcinogenesis in northern India

BACKGROUND

Interleukin (IL)-8 -251 T/A and IL-10 (-1082 G/A and -819/592 C/T) polymorphisms and their expression may influence gastritis, atrophy, intestinal metaplasia (IM) and gastric cancer (GC) following H. pylori infection.

METHODS

Genotyping of these genes was performed (ASO-PCR) in 200, 182 and 250 with GC, functional dyspepsia (FD) and healthy controls (HC), respectively. Anti-H. pylori IgG-antibody was tested in all and serums IL-8 and IL-10 were measured randomly in 60 subjects of each group by ELISA.

RESULTS

Pro-(IL-8)-251 AA and anti-inflammatory (IL-10)-819 TT genotypes were commoner among GC than HC (p = 0.023, OR 1.86 [1.09-3.2] and p = 0.020, OR 2.0 [1.11-3.5]) but comparable with FD. IL-8 AA and IL-10-819 T allele carriage was also commoner in H. pylori-infected GC than HC (p = 0.011, OR 2.47 [1.23-5.0], and p = 0.018, OR 2.3 (1.16-4.59). IL-10-1082 G/A genotype and haplotypes (ACC, GCC, ATA and GTA) were comparable in all groups. Circulating levels of IL-8 and IL-10 were higher among GC than HC but comparable to FD (IL-8; 57.64 [6.44-319.46] vs. 54.35 [4.24-318.96] and 26.33 [4.67-304.54] pg/ml, p < 0.001 and IL-10; 15.47 [1.01-270.87] vs. 12.28 [0.96-64.88] and 3.79 [1.24-56.65], p < 0.001 for GC vs. HC). IL-8/IL-10 ratio was lower among GC than HC but higher than FD (3.7 [0.18-38.41] vs. 6.59 [0.98-130.2], p < 0.001 and 4.22 [0.15-61.4], p < 0.01). Circulating levels of IL-8, IL-10 and IL-8/lL-10 ratios were different among H. pylori-infected and non-infected GC than HC (p < 0.001, p < 0.001 and p < 0.01).

CONCLUSIONS

Pro-(IL-8)-251 T/A and anti-inflammatory (IL-10)-819 C/T gene polymorphisms and their circulating levels may play a role in H. pylori-associated gastric carcinogenesis in northern India.

Association between pro-(IL-8) and anti-inflammatory (IL-10) cytokine variants and their serum levels and H. pylori-related gastric carcinogenesis in northern India

BACKGROUND

Interleukin (IL)-8 -251 T/A and IL-10 (-1082 G/A and -819/592 C/T) polymorphisms and their expression may influence gastritis, atrophy, intestinal metaplasia (IM) and gastric cancer (GC) following H. pylori infection.

METHODS

Genotyping of these genes was performed (ASO-PCR) in 200, 182 and 250 with GC, functional dyspepsia (FD) and healthy controls (HC), respectively. Anti-H. pylori IgG-antibody was tested in all and serums IL-8 and IL-10 were measured randomly in 60 subjects of each group by ELISA.

RESULTS

Pro-(IL-8)-251 AA and anti-inflammatory (IL-10)-819 TT genotypes were commoner among GC than HC (p = 0.023, OR 1.86 [1.09-3.2] and p = 0.020, OR 2.0 [1.11-3.5]) but comparable with FD. IL-8 AA and IL-10-819 T allele carriage was also commoner in H. pylori-infected GC than HC (p = 0.011, OR 2.47 [1.23-5.0], and p = 0.018, OR 2.3 (1.16-4.59). IL-10-1082 G/A genotype and haplotypes (ACC, GCC, ATA and GTA) were comparable in all groups. Circulating levels of IL-8 and IL-10 were higher among GC than HC but comparable to FD (IL-8; 57.64 [6.44-319.46] vs. 54.35 [4.24-318.96] and 26.33 [4.67-304.54] pg/ml, p < 0.001 and IL-10; 15.47 [1.01-270.87] vs. 12.28 [0.96-64.88] and 3.79 [1.24-56.65], p < 0.001 for GC vs. HC). IL-8/IL-10 ratio was lower among GC than HC but higher than FD (3.7 [0.18-38.41] vs. 6.59 [0.98-130.2], p < 0.001 and 4.22 [0.15-61.4], p < 0.01). Circulating levels of IL-8, IL-10 and IL-8/lL-10 ratios were different among H. pylori-infected and non-infected GC than HC (p < 0.001, p < 0.001 and p < 0.01).

CONCLUSIONS

Pro-(IL-8)-251 T/A and anti-inflammatory (IL-10)-819 C/T gene polymorphisms and their circulating levels may play a role in H. pylori-associated gastric carcinogenesis in northern India.

Noncoding Genomics in Gastric Cancer and the Gastric Precancerous Cascade: Pathogenesis and Biomarkers

Gastric cancer is the fifth most common cancer and the third leading cause of cancer-related death, whose patterns vary among geographical regions and ethnicities. It is a multifactorial disease, and its development depends on infection by Helicobacter pylori (H. pylori) and Epstein-Barr virus (EBV), host genetic factors, and environmental factors. The heterogeneity of the disease has begun to be unraveled by a comprehensive mutational evaluation of primary tumors. The low-abundance of mutations suggests that other mechanisms participate in the evolution of the disease, such as those found through analyses of noncoding genomics. Noncoding genomics includes single nucleotide polymorphisms (SNPs), regulation of gene expression through DNA methylation of promoter sites, miRNAs, other noncoding RNAs in regulatory regions, and other topics. These processes and molecules ultimately control gene expression. Potential biomarkers are appearing from analyses of noncoding genomics. This review focuses on noncoding genomics and potential biomarkers in the context of gastric cancer and the gastric precancerous cascade.

Pattern-recognition receptors and gastric cancer

Chronic inflammation has been associated with an increased risk of several human malignancies, a classic example being gastric adenocarcinoma (GC). Development of GC is known to result from infection of the gastric mucosa by Helicobacter pylori, which initially induces acute inflammation and, in a subset of patients, progresses over time to chronic inflammation, gastric atrophy, intestinal metaplasia, dysplasia, and finally intestinal-type GC. Germ-line encoded receptors known as pattern-recognition receptors (PRRs) are critical for generating mature pro-inflammatory cytokines that are crucial for both Th1 and Th2 responses. Given that H. pylori is initially targeted by PRRs, it is conceivable that dysfunction within genes of this arm of the immune system could modulate the host response against H. pylori infection, and subsequently influence the emergence of GC. Current evidence suggests that Toll-like receptors (TLRs) (TLR2, TLR3, TLR4, TLR5, and TLR9), nucleotide-binding oligomerization domain (NOD)-like receptors (NLRs) (NOD1, NOD2, and NLRP3), a C-type lectin receptor (DC-SIGN), and retinoic acid-inducible gene (RIG)-I-like receptors (RIG-I and MDA-5), are involved in both the recognition of H. pylori and gastric carcinogenesis. In addition, polymorphisms in genes involved in the TLR (TLR1, TLR2, TLR4, TLR5, TLR9, and CD14) and NLR (NOD1, NOD2, NLRP3, NLRP12, NLRX1, CASP1, ASC, and CARD8) signaling pathways have been shown to modulate the risk of H. pylori infection, gastric precancerous lesions, and/or GC. Further, the modulation of PRRs has been suggested to suppress H. pylori-induced inflammation and enhance GC cell apoptosis, highlighting their potential relevance in GC therapeutics. In this review, we present current advances in our understanding of the role of the TLR and NLR signaling pathways in the pathogenesis of GC, address the involvement of other recently identified PRRs in GC, and discuss the potential implications of PRRs in GC immunotherapy.

Variants of interleukin-16 associated with gastric cancer risk

AIM

We conducted a case-control matched study to investigate the role of IL-16 gene polymorphisms, rs4072111, rs1131445, rs4778889 and rs11556218, in the risk of gastric cancer in a Chinese population, also performing subgroup analysis by subsites.

METHODS

To test the hypothesis of involvement, we analyzed the four SNPs of IL16 in 347 cancer patients and 368 controls. Demographic data and other information were collected using a newly designed questionnaire. Genotyping of IL16 (rs4072111, rs1131445, rs4778889 and rs11556218) was performed in a 384-well plate format on the MassARRAY® platform.

RESULTS

In our study, we found the gastric cancer patients were more likely to be male and have a family history of cancer (P < 0.05). We found the rs4778889 CC and rs11556218 GG genotype was significantly associated with 1.97 and 1.84-fold increased risk of non-cardia gastric cancer, while we did not find significant association between the four IL-16 SNPs and cardia gastric cancer.

CONCLUSIONS

In conclusion, our study indicated that IL-16 rs4778889 CC and rs11556218 GG genotypes are associated with an increased risk of non-cardia gastric cancer in a Chinese population. Our results offer insights into the influence of IL-16 on development of gastric cancer.

Ethnic differences in gastric cancer genetic susceptibility: Allele flips of interleukin gene

Polymorphisms in promoter regions of inflammatory cytokines have been widely studied, and potentially functional polymorphisms have been discovered. Conflicting results from meta-analyses of interleukin (IL)-1B and IL-10 polymorphisms show differences in gastric cancer susceptibilities between Caucasian and Asian populations. In particular, we note the suggestion of an allele flip in IL-1B and IL-10 gene polymorphisms. In Asian populations, the IL-1B-1464G/-511C/-31T haplotype indicates risk for gastric cancer, while the opposite haplotype, IL-1B-1464C/-511T/-31C is the risk-related allele in Caucasians. Furthermore, while IL-10-1082G/-819C/-592C is associated with gastric cancer in Asians, IL-10-1082A/-819T/-592T is linked to gastric cancer risk in Caucasians. These seemingly contradictory results may be attributed to distinct carcinogenic mechanisms underlying the different gastric cancer subtypes. The allele flip observed in IL-10 and gastric cancer appears to reflect allelic heterogeneity, similar to that observed in IL-1B. In this review, we focus on the allele flip phenomenon observed between different ethnic groups in an effort to resolve certain controversial results from recent studies on interleukin polymorphism. In addition, we re-emphasize the importance of stratifying gastric cancer subtypes based on anatomical site and Lauren classification to prevent false associations arising through dilution of true ones.

Genetic susceptibility and gastric cancer risk: the importance of meta-analyses as a statistical tool

Gastric cancer (GC) is a complex disease and a worldwide health burden due to its high prevalence and poor prognosis. A deeper knowledge of the factors involved in the development and progression of GC could help to identify subpopulations at risk that therefore require surveillance or early treatment strategies. Current research is based on the study of genetic variants that confer a higher risk of GC and their interactions with environmental exposure. Recently, meta-analysis has emerged as an important statistical method involving pooling of data from individual association studies to increase statistical power and obtain more conclusive results. Given the importance of chronic inflammation in the process of gastric carcinogenesis, the present article reviews the most recent meta-analyses of the contribution of cytokine gene polymorphisms to GC risk.

Biomarkers of Helicobacter pylori-associated gastric cancer

Helicobacter pylori-associated gastric cancer is a major cause of morbidity and mortality worldwide, and is predicted to become even more common in developing countries as the population ages. Since gastric cancer develops slowly over years to decades, and typically progresses though a series of well-defined histologic stages, cancer biomarkers have potential to identify asymptomatic individuals in whom surgery might be curative, or even those for whom antibiotics to eradicate H. pylori could prevent neoplastic transformation. Here we describe some of the challenges of biomarker discovery, summarize current approaches to biomarkers of gastric cancer, and explore some recent novel strategies.

Why interleukin-10 supplementation does not work in Crohn’s disease patients

Inflammatory bowel diseases (IBD) such as Crohn’s disease (CD) or ulcerative colitis are chronic intestinal disorders, which are on the increase in “Westernised” countries. IBD can be caused by both genetic and environmental factors. Interleukin-10 (IL-10) is an immunoregulatory cytokine that has been identified as being involved in several diseases including IBD. Studies have shown that polymorphisms in the promoter region reduce serum levels of IL-10 and this reduction has been associated with some forms of IBD. Mouse models have shown promising results with IL-10 supplementation, as such IL-10 supplementation has been touted as being a possible alternative treatment for CD in humans. Clinical trials have shown that recombinant human IL-10 is safe and well tolerated up to a dose of 8 μg/kg. However, to date, the results of the clinical trials have been disappointing. Although CD activity was reduced as measured by the CD activity index, IL-10 supplementation did not result in significantly reduced remission rates or clinical improvements when compared to placebo. This review discusses why IL-10 supplementation is not effective in CD patients currently and what can be addressed to potentially make IL-10 supplementation a more viable treatment option in the future. Based on the current research we conclude that IL-10 supplementation is not a one size fits all treatment and if the correct population of patients is chosen then IL-10 supplementation could be of benefit.

Association of polymorphisms and haplotype in the region of TRIT1, MYCL1 and MFSD2A with the risk and clinicopathological features of gastric cancer in a southeast Chinese population

To explore the association of polymorphisms in the region of three neighboring genes TRIT1, MYCL1 and MFSD2A with risk and clinicopathological features of gastric cancer, 19 tagging SNPs in this region were genotyped using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry in a case-control study of 610 Chinese gastric cancer patients and 608 cancer-free controls. MFSD2A rs4233508 T>C CC genotype was associated with an increased risk of gastric cancer in younger patients and an increased risk of moderately/well-differentiated intestinal-type gastric cancer (adjusted odds ratio [OR], 1.74 and 1.50, respectively). TRIT1 rs11581557 T>G TG was associated with lymph node metastasis (TG versus TT/GG, adjusted OR, 1.64). MFSD2A rs12083239 GC genotype and TRIT1 rs2172362 or rs230310 homozygous genotype were associated with Lauren's classification (GC versus GG, adjusted OR, 1.69; GC versus GG/CC, adjusted OR, 1.74) and tumor site (rs2172362: CC versus CT, adjusted OR, 1.71; CC/TT versus CT, adjusted OR, 1.62; rs230310: CC versus CT, adjusted OR, 1.75; CC/TT versus CT, adjusted OR, 1.67) of gastric cancer, respectively. One TRIT1 haplotype, CCGT, was associated with lymph node metastasis and tumor site of gastric cancer (CCGT versus TTTT, adjusted OR, 1.91 and 1.55). This is believed to be the first report that several tagging SNPs and haplotypes in TRIT1, MYCL1 and MFSD2A region are significantly associated with risk and clinicopathological features of gastric cancer in a Chinese population. The findings might be useful for risk assessment and prognosis prediction of gastric cancer.

Interaction between interleukin-10 (IL-10) polymorphisms and dietary fibre in relation to risk of colorectal cancer in a Danish case-cohort study

Background

More than 50% of the colorectal cancer (CRC) etiology has been attributed to diet. Established or suspected dietary factors modifying risk of CRC are red meat, cereals, fish, and fibre. Diet and lifestyle may be linked to cancer through inflammation. Interleukin-10 (IL-10) is an anti-inflammatory cytokine. We wanted to test if dietary factors and IL10 polymorphisms interact in relation to colorectal carcinogenesis.

Methods

The functional IL10 polymorphism C-592A (rs1800872) and the marker rs3024505 were assessed in relation to diet and lifestyle in a nested case-cohort study of 378 CRC cases and 775 randomly selected participants from a prospective study of 57,053 persons. Genotyping data on the IL10 polymorphism C-592A, smoking and non-steroidal anti-inflammatory drugs (NSAID) was retrieved from Vogel et al. (Mutat Res, 2007; 624:88). Incidence rate ratios (IRR) and 95% Confidence Interval (95% CI) were calculated.

Results

No associations were found between the IL10 rs3024505 polymorphism and risk of CRC. There was interaction between rs3024505 and dietary fibre (P-value for interaction = 0.01). IL10 rs3024505 homozygous wildtype carriers were at 27% reduced risk of CRC per 10 g fibre per day (95% CI: 0.60-0.88) whereas variant carriers had no risk reduction by fibre intake. Also, interaction between IL10 C-592A and intake of fibre was found (P-value for interaction = 0.02). Among those eating <17.0 grams of fibre per day, carriers of an C-592A variant allele had a statistically significantly higher risk of colorectal cancer compared to homozygous wildtypes. No significant differences in colorectal cancer risk were observed between the reference group (CC and <17.0 g/day) and carriers of one C-592A variant allele eating 17.0 or more grams of dietary fibre per day. This suggests that the increased risk due to carrying the variant allele can be overcome by higher fibre intake. No interactions between IL10 polymorphisms and dietary meat, cereal, or fish intake, or between IL10 rs3024505 and smoking or NSAID use were found.

Conclusions

In this northern Caucasian cohort we found interaction between IL10 and dietary fibre in CRC carcinogenesis. High intake of fibre seems to protect against CRC among individuals with IL10 related genetic susceptibility to CRC. This finding should be evaluated in other prospective and population-based cohorts with different ethnic groups.