Increased Risk Of Gastric Cancer Research Articles

Impacts of Matrix Metalloproteinase-8 Genotypes, Smoking, Alcohol Drinking, and Helicobacter Pylori Infection on Gastric Cancer.

In gastric cancer (GCa) tissues, mRNA expression of matrix metalloproteinase-8 (MMP-8) is notably reduced compared to healthy tissues. Furthermore, abnormally low or elevated serum levels of MMP-8 have been linked to a significantly poor prognosis. The involvement of MMP-8 genotypes in susceptibility to GCa remains underexplored. We aimed to assess the influence of MMP-8 genotypes on GCa susceptibility and their potential interactions with smoking, alcohol consumption, and Helicobacter pylori (H. pylori) infection. The study utilized polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) to analyze MMP-8 rs11225395, rs34009635, and rs35866072 genotypes in 161 GCa patients and 483 controls. No statistically significant difference was detected in the distribution of genotypic (p for trend=0.3635) or allelic (p=0.1954) frequencies of MMP-8 rs11225395. Under a dominant model, combined CT+TT genotypes showed no association with GCa risk [odds ratio (OR)=0.77, 95% confidence interval (95%CI)=0.54-1.10, p=0.1852]. Similarly, no association was observed for MMP-8 rs34009635 or rs35866072. Importantly, individuals with the MMP-8 rs11225395 CC genotype demonstrated a significant increase in GCa risk when exposed to smoking (OR=4.04, 95%CI=2.28-7.16, p=0.0001), alcohol consumption (OR=2.83, 95%CI=1.64-4.89, p=0.0002), and H. pylori infection (OR=3.53, 95%CI=2.12-5.90, p=0.0001). The findings indicate that individuals carrying the MMP-8 rs11225395 CC genotype have increased susceptibility to GCa, especially when combined with risk factors, such as smoking, alcohol consumption, and H. pylori infection. These results suggest that MMP-8 genotype-based preventive strategies, including lifestyle alterations and targeted infection treatments, may be valuable in mitigating GCa development.

Associations between CDH1 gene polymorphisms and the risk of gastric cancer: A meta-analysis based on 44 studies.

Numerous studies have investigated the association between CDH1 polymorphisms and gastric cancer (GC) risk. However, the results have been inconsistent and controversial. To further determine whether CDH1 polymorphisms increase the risk of GC, we conducted a meta-analysis by pooling the data. Relevant case-control studies were collected from PubMed, Embase, Web of Science and Cochrane databases up to January 7, 2024. Subsequently, odds ratios (ORs) with 95% confidence intervals (CIs) were used to evaluate the strength of correlations. A sensitivity analysis was performed to evaluate the robustness and reliability of these included studies. A total of 25 articles including 44 studies, were included in this meta-analysis, including 26 studies on rs16260, 6 studies on rs3743674, 7 studies on rs5030625, and 5 studies on rs1801552. The pooled results showed that rs16260 was remarkably associated with an increased GC risk of GC among Caucasians. Moreover, the rs5030625 variation dramatically enhanced GC predisposition in the Asian population. However, no evident correlations between CDH1 rs3743674 and rs1801552 polymorphisms and GC risk were observed. Our findings suggested that CDH1 gene polymorphisms were significantly correlated with GC risk, especially in rs16260 and rs5030625 polymorphisms.

Interaction Between Hypoxia-Inducible Factor 1-alpha Gene Polymorphism and Helicobacter pylori Infection on Gastric Cancer in a Chinese Tibetan Population.

To investigate the impact of four single nucleotide polymorphisms (SNPs) of the HIF1α gene and its interaction with Helicobacter pylori (H. pylori) infection on susceptibility to gastric cancer (GC).Logistic regression was used to test the relationship between four SNPs of HIF1α gene and the susceptibility of GC. A generalized multifactor dimensionality reduction (GMDR) model was used to assess the HIF1α gene-H. pylori infection interaction.Logistic regression analysis indicated that both the rs11549465-CT genotype and the T allele were associated with an increased risk of GC, adjusted OR (95% CI) were 1.63 (1.09-2.20) (CT vs. CC) and 1.70 (1.13-2.36) (T vs. C), respectively. We also found that both the rs11549467-A allele and rs11549467-GA genotype were associated with an increased risk of GC, and adjusted OR (95% CI) were 2.21 (1.61-2.86) (GA vs. GG), 2.13 (1.65-2.65) (A vs. G), respectively. However, no statistically significant impact of rs2057482 or rs1957757 on risk of GC was found. The GMDR model indicated a statistically significant two-dimensional model combination (including rs11549467 and H. pylori infection). The selected model had testing balanced accuracy of 0.60 and the best cross-validation consistencies of 10/10 (p = 0.0107). Compared with H. pylori infection negative participants with rs11549467-GG genotype, H. pylori positive participants with the rs11549467-GA genotype had the highest GC risk, the OR (95% CI) was 3.04 (1.98-4.12).The rs11549467-A allele and rs11549467-GA genotype was associated with increased GC risk. Additionally, the gene-environment interaction between HIF-1α-rs11549467 and H. pylori infection was also correlated with an increased risk of GC.

Ethnic-specific associations between body mass index and gastric cancer: a Mendelian randomization study in European and Korean populations.

Given the uncertainties surrounding the associations in previous epidemiological studies, we conducted linear and nonlinear Mendelian randomization (MR) studies to evaluate whether body mass index (BMI) associated with gastric cancer (GC) risk in European and Korean. Genome-wide association study-summary statistics were used from the Pan-UK Biobank, the Genetic Investigation of Anthropometric Traits consortium, the K-CHIP consortium, and BioBank Japan. BMI-associated single nucleotide polymorphisms (SNPs) were used as instrumental variables (IVs) in MR to identify the association between BMI and GC. Both linear and nonlinear MR analyses were performed. Sensitivity analyses were also conducted for individuals below or above a BMI of 24kg/m2. The study used 22 and 55 SNPs as IVs for BMI in European and Korean populations, respectively. Genetically predicted BMI was positively associated with GC risk in the European population (Odds ratio per 1kg/m2 increase; 95% CI = 1.17; 1.01-1.36 using simple median method), but no significant association was observed in the Korean population. However, the nonlinear MR identified a U-shaped association between BMI and GC in the Korean population, with both low and high BMIs associated with increased GC risk. A BMI of 24kg/m2 presented the lowest risk. Sensitivity analyses did not yield any genome-wide significant SNPs. While MR analysis suggests a linear association between BMI and GC in those of European ancestry, nonlinear MR hints at a U-shaped association in Koreans. This suggests the association between BMI and GC risk may vary according to ethnic ancestry.

Update on the association of miR-149 rs2292832 C>T polymorphism with gastric cancer risk: A meta-analysis study of gastrointestinal cancers.

Single nucleotide polymorphisms in microRNAs are believed to affect the occurrence and progression of cancer by altering the expression and biological functions of microRNAs. Several studies investigated the role of the miR-149 rs2292832 C>T polymorphism on the risk of gastric cancer (GC), but got conflicting results. We performed a comprehensive and systematic search through the PubMed MEDLINE, Google Scholar, Science Direct, Scopus, CNKI, and Web of science, 8 studies were included in the meta-analysis to determine whether miR-149 rs2292832 C>T polymorphism contributed to the risk of GC. Pooled data indicated that miR-149 rs2292832 C>T polymorphism was not associated with GC risk. In the stratified analysis by ethnicity, miR-149 rs2292832 C>T polymorphism significantly increased GC risk under the allele comparison model (odds ratio [OR] = 1.27, 95% CI = 1.04-1.55, Pheterogeneity = 0.18, P = .02), recessive model (OR = 1.44, 95% CI = 1.04-2.01, Pheterogeneity = 0.19, P = .03) among Caucasians; but decreased GC risk under the allele comparison model (OR = 0.89, 95% CI = 0.81-0.98, Pheterogeneity = 0.22, P = .02) and dominant model (OR = 0.82, 95% CI = 0.72-0.93, Pheterogeneity = 0.15, P = .01) among Asian. Our meta-analysis suggests a positive correlation between miR-149 rs2292832 C>T polymorphism and GC development among Caucasians, but negative correlation among Asian population.

Impact of interaction between interleukin-6 gene polymorphism and Helicobacter pylori infection on susceptibility to gastric cancer.

This study aimed to evaluate the association between four single nucleotide polymorphisms (SNPs) of the interleukin-6 (IL-6) gene and gastric cancer (GC), and impact of interaction between IL-6 SNPs and Helicobacter pylori (H. pylori ) infection on susceptibility to GC. Logistic regression was used to test the relationships between four SNPs of IL-6 gene and GC susceptibility. A generalized multifactor dimensionality reduction (GMDR) model was employed to assess the interaction effect between IL-6 gene and H. pylori infection on GC risk. Logistic regression analysis indicated that the rs1800795-C allele was associated with increased GC risk, adjusted ORs (95% CI) were 1.80 (1.21-2.41) (CC vs. GG) and 1.68 (1.09-2.30) (C vs. G), respectively. The rs10499563-C allele was associated with decreased risk of GC, and adjusted ORs (95% CI) were 0.62 (0.31-0.93) (TC vs. TT), 0.52 (0.18-0.89) (CC vs. TT) and 0.60 (0.29-0.92) (C vs. T), respectively. GMDR methods found a two-dimensional model combination (including rs1800795 and H. pylori infection) was statistically significant. The selected model had testing balanced accuracy of 59.85% and the best cross-validation consistencies of 10/10 ( P = 0.0107). Compared with H. pylori -negative subjects with rs1800795- GG genotype, H. pylori -positive participants with GC or CC genotype had the highest risk of GC, the OR (95% CI) was 3.34 (1.78-4.97). The rs1800795-C allele was associated with increased GC risk and the rs10499563-C allele was associated with decreased GC risk. The interaction between rs1800795 and H. pylori infection was also correlated with increased risk of GC.

Gastric Cancer Risk in Patients with Long-Term Use of Proton Pump Inhibitors: A Systematic Review and Meta-Analysis of Observational and Interventional Studies.

A growing number of studies that differ in design, quality, and results report an association between the use of proton pump inhibitors (PPIs) and the risk of gastric cancer (GC). We conducted a systematic review and meta-analysis, when possible, of observational and interventional studies examining PPI use and risk of GC. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We identified studies fully published in English through January 2023 using MeSH and non-MeSH keywords. We used random effects models to calculate pooled risk estimates with 95% confidence interval (CI) between PPI use and overall GC, cardia GC, and non-cardia GC. We estimated heterogeneity (I2) among studies. We examined the effect of study design and quality, GC site, H. pylori infection, and PPI duration. We assessed quality using the Newcastle-Ottawa Quality Assessment Scale and Risk Of Bias In Non-randomized Studies of Interventions. We identified 15 observational studies, of which 13 were included in the meta-analysis (six cohort and seven case-control). There was a modest 1.67-fold increase in overall GC risk (95% CI 1.39, 2.00) and no increase in cardia GC risk [odds ratio (OR) 1.12; 95% CI 0.80, 1.56] with PPI use. However, there was high heterogeneity (I2 = 61.3%, p = 0.004) among studies. All but one study had at least moderate risk of bias. In the six studies accounting for H. pylori, GC risk associated with PPI use increased slightly (OR 1.78; 95% CI 1.25, 2.52). Duration response was not reported consistently to allow pooled estimates. We identified only one interventional randomized controlled study that included GC as an outcome of interest, and it did not show increased GC risk. The overall available evidence is not supportive of a meaningful change in GC risk, either cardia or non-cardia, with PPI use.

Gastric cancer risk in the elderly is associated with omeprazole use and inversely associated with aspirin use.

The association between long-term omeprazole use and gastric cancer (GC) risk is controversial. The aim of this study was to investigate the incidence of GC in elderly community-dwelling omeprazole chronic users with/without aspirin compared to non-users. The registry of a large health management organization was searched for all community-dwelling members aged ≥65 years from January 2002 to December 2016. Data on demographics, background parameters, and chronic omeprazole and aspirin use (>11 prescriptions/year) were retrieved. Those diagnosed with new-onset GC during the study period (from January 2003) were identified. Of 51 405 subjects who met the inclusion criteria, 197 were diagnosed with GC during a mean follow-up period of 8.74 ± 4.16 years. This group accounted for 0.7% of PPI chronic users (72/11 008) and 0.3% (125/40 397) of nonusers (P < 0.001). GC risk was directly associated with omeprazole chronic use [hazard ratio (HR) 2.03, 95% confidence interval (CI): 1.51-2.73, P < 0.001] and inversely associated with aspirin chronic use (HR 0.55, 95% CI: 0.40-0.75, P < 0.001). Each year of omeprazole use increased GC risk by 9%, and each year of aspirin use decreased GC risk by 10% among omeprazole chronic users. The lowest rate of GC was found in omeprazole nonusers/ aspirin chronic users, and the highest, in omeprazole chronic users/aspirin nonusers. Higher GC rate was associated with omeprazole chronic use and inversely associated with aspirin chronic use relative to omeprazole nonuse in community-dwelling elderly.

Mutual association between family history of gastric and colorectal cancer and risk of gastric and colorectal cancer.

We evaluated the associations between gastric cancer (GC) family history (FH) and colorectal cancer (CRC) risk and between CRC FH and GC/gastric adenoma risk. We used data of participants who underwent national cancer screening between 2013 and 2014. Participants with GC or CRC FH in first-degree relatives (n=1 172 750) and those without cancer FH (n=3 518 250) were matched 1:3 by age and gender. Of the 1 172 750 participants with a FH, 871 104, 264 040, and 37 606 had FHs of only GC, only CRC, and both GC and CRC, respectively. The median follow-up time was 4.8years. GC and CRC FHs were associated with increased GC and CRC risks, respectively. GC FH was associated with CRC risk (adjusted hazard ratio 1.05; 95% confidence interval [CI] 1.01-1.10), whereas CRC FH was not associated with the risk of GC or gastric adenoma. However, gastric adenoma risk increased 1.62-fold (95% CI 1.40-1.87) in participants with FHs of both GC and CRC, demonstrating a significant difference with the 1.39-fold (95% CI 1.34-1.44) increase in participants with only GC FH. Furthermore, GC risk increased by 5.32 times (95% CI 1.74-16.24) in participants with FHs of both GC and CRC in both parents and siblings. GC FH was significantly associated with a 5% increase in CRC risk. Although CRC FH did not increase GC risk, FH of both GC and CRC further increased the risk of gastric adenoma. FHs of GC and CRC may affect each other's neoplastic lesion risk.

STUDY ON THE PRESENCE OF OIPA AND DUPA GENES OF HELICOBACTER PYLORI IN GASTRIC CANCER PATIENTS

Objectives: To determine the percentage of Helicobacter pylori (H. pylori) carrying the outer inflammatory protein A (oipA), duodenal ulcer promotion (dupA) genes, and their relationship with endoscopic imaging, histopathology, and the risk of gastric cancer (GC). Subjects and methods: A cross-sectional study on 89 GC patients, compared with 90 patients with chronic gastritis (CG) with H. pylori infection, diagnosis based on histopathological results at Military Hospital 103 and Central Military Hospital 108 from August 2019 to May 2022. Determination of oipA, dupA genes of H. pylori by realtime-PCR technique on biopsy tissue samples of the gastric mucosa. Results: The percentage of H. pylori carrying the oipA and dupA genes was 30.2% and 10.1%, respectively. The relationship between bacterial infection harboring these 2 genes and endoscopic images and histopathology of GC has not been recorded. There was no difference in the prevalence of H. pylori carrying the oipA and dupA genes infection between the GC and CG groups (p &gt; 0.05). Conclusion: The infection of H. pylori with oipA and dupA genes positive may not increase GC risk in Vietnamese.

Exposure to Commonly Used Drugs and the Risk of Gastric Cancer: An Umbrella Review of Meta-Analyses.

Recently, attention has been paid to some medications and gastric cancer (GC) risk. This review aimed to evaluate associations between commonly used drugs and GC risk and to grade evidence from published systematic reviews and meta-analyses. This umbrella review was registered in PROSPERO (CRD42022320276). The systematic reviews and meta-analyses of observational studies were retrieved by searching Embase, PubMed, and Web of Science. The evidence strength of commonly used drugs and GC risk was categorized into four grades: weak, suggestive, highly suggestive, and strong. Of 19 associations between commonly used drugs and GC risk and its subtypes, none was supported by convincing or highly suggestive evidence. The risk of GC related to non-steroidal anti-inflammatory drugs (NSAIDs), non-aspirin NSAIDs, and acid-suppressive drugs, as well as the risk of non-cardia GC related to NSAIDs and aspirin, was supported by suggestive evidence. The results showed that a reduced GC risk was associated with two drug types (NSAIDs and non-aspirin NSAIDs), and an increased GC risk was associated with acid-suppressing drugs at the suggestive evidence level. Moreover, NSAIDs and aspirin reduced non-cardia GC risk as supported by suggestive evidence. However, the evidence supporting statins or metformin in reducing GC risk was weak, and thus future studies are required to clarify these associations.

Association between the TP53 Arg72Pro Polymorphisms and Gastric Cancer Risk: An Updated Meta-Analysis and Re-Analysis of Systematic Meta-Analyses

Background: A latest Meta-analysis on TP53 Arg72Pro polymorphism with gastric cancer (GC) risk was published in 2015 including 20 literatures, while our study included 43 studies. Moreover, the results of previously published original studies were inconsistent and the credibility of the significant correlation between the statistical results has been ignored. Therefore, an updated Meta-analysis was conducted to further explore these associations. Objective: To explore whether these two gene polymorphisms are related to the risk, clinical manifestations, and pathological features of GC. Methods: We searched several Chinese and English databases. The crude odds ratio (OR) with 95% confidence interval (CI) was used to evaluate the correlation. In addition, false positive reporting probability (FPRP), bayesian false discovery probability (BFDP), and Venice criteria were used to assess the reliability of statistically significant correlation. Results: Overall, the TP53 Arg72Pro polymorphism was related to a significantly increased GC risk (AP vs. AA: OR = 1.12, 95% CI = 1.02 - 1.24; PP + AP vs. AA: OR = 1.12, 95% CI = 1.02 - 1.24; P vs. A: OR = 1.07, 95% CI = 1.00 - 1.15). However, after excluding the low quality and Hardy–Weinberg Disequilibrium (HWD) studies, significant changes were found on the TP53 Arg72Pro polymorphism with GC risk in Caucasians (PP vs. AA: OR = 1.48, 95% CI = 1.01 - 2.16) and non-gastric cancer control groups (PP vs. AP + AA: OR = 1.33, 95% CI = 1.07 - 1.64)). However, the above significant results were considered unreliable after being adjusted with Bayesian error detection probability (BFDP) and false positive reporting probability (FPRP). These unreliable results were confirmed again, and no new reliable results were found in the further sensitivity analysis (only studies that met the quality assessment criteria). Conclusions: After considering the quality of the study and the reliability of the results, this Meta-analysis showed that TP53 codon 72 polymorphisms had no significant correlation with GC risk. Because of various confounding factors, the result that these polymorphisms increase GC risk is more likely to be a false positive result.

Sex-dependent associations between MAP3K1 gene polymorphisms and soy products with the gastric cancer risk in Korea: a case-control study

Background/ObjectivesThe hormone-dependent effect of MAP3K1 gene polymorphisms may explain sex-specific differences in gastric cancer (GC) risk. Phytoestrogens have been shown to interact with this genetic factor. Here, we investigated the association between MAP3K1 gene polymorphisms and GC risk by sex and whether these associations differ depending on soy products intake.MethodsParticipants aged 20–79 years were recruited from two hospitals between December 2002 and September 2006. In all, 440 cases and 485 controls were recruited, among, 246 pairs of cases and controls, matched by sex, age (± 5 years), study admission period (± 1 years), and hospital, were included for the analysis.ResultsIn dominant model, men with the A allele of rs252902 showed significantly increased GC risk (odd ratio; OR=2.19, 95% confidence interval; CI=1.31–3.64) compared to GG homozygotes. When stratified by intake of soy products, men with the A allele of rs252902 and low intake of soy products showed significantly higher GC risk (OR=3.29, 95% CI=1.55–6.78) than that in GG homozygotes.ConclusionsMen with the risk allele of MAP3K1 had a significantly increased GC risk compared to GG homozygotes; this trend was more pronounced in those with low intake of soy products.

Interaction Between Vascular Endothelial Growth Factor Gene Polymorphism and Smoking on Gastric Cancer Risk in Chinese Han Population.

Aim: In this study, we aimed to evaluate the associations of vascular endothelial growth factor (VEGF) gene single nucleotide polymorphisms (SNPs) and its interaction with current smoking with gastric cancer (GC) risk in the Chinese Han population. Methods: We used logistic regression model to test the association between VEGF gene polymorphism and the risk of GC. The association strength was evaluated by odds ratio (OR) and 95% confidence interval (CI) calculated using logistic regression. Generalized multifactor dimensionality reduction (GMDR) was used to analyze the effect of the interaction between VEGF gene and current smoking on GC risk. Results: Logistic regression analysis showed that the risk of GC was significantly higher in rs10434 -G allele carriers than that in AA genotype carriers (AG + GG and AA), and the adjusted OR (95% CI) = 1.64 (1.24–2.08). In addition, we found a significantly higher GC risk in subjects with rs833061-T allele than those with CC allele (CT + TT and CC), adjusted or (95% CI) = 1.43 (1.10–1.87). We also found a statistically significant two- locus model (p = 0.018), including rs10434 and current smoking, indicating a significant interaction between rs10434 and current smoking on the risk of GC. Hierarchical analysis found that current smokers with AG or GG genotype have the highest GC risk, compared to never- smokers with AA genotype, OR (95% CI) = 2.43 (1.64–3.28). Conclusion: We found that rs10434 -G and rs833061-T alleles, gene- environment interaction between rs10434, and current smoking were all related to increased GC risk.

MTRR rs1532268 polymorphism and gastric cancer risk: evidence from a meta-analysis.

ObjectiveThe methionine synthase reductase (MTRR) gene encodes the MTRR enzyme involved in the metabolic pathway of homocysteine. Several studies investigated the effect of the MTRR rs1532268 gene polymorphism on the risk of gastric cancer (GC), but the results have been inconsistent.MethodsWe performed a comprehensive and systematic search of PubMed, Google Scholar, MEDLINE, Science Direct, Scopus, CNKI, and Web of Science. Five studies were included in this meta-analysis to determine whether MTRR rs1532268 polymorphism contributes to the risk of GC.ResultsPooled data indicated that the MTRR rs1532268 polymorphism significantly increased GC risk under the allele comparison model (odds ratio [OR] = 1.14, 95% confidence interval [CI] = 1.01–1.29) and dominant model (OR = 1.14, 95% CI = 1.00–1.30). In the analysis stratified by ethnicity, no relationship was found in Whites or Asians.ConclusionOur meta-analysis suggests a positive correlation between MTRR rs1532268 polymorphism and GC development.

Rs2671655 single nucleotide polymorphism modulates the risk for gastric cancer in Helicobacter pylori-infected individuals: a genome-wide association study in the Korean population.

ObjectiveTo identify genetic variations which is associated with gastric cancer (GC) risk according to Helicobacter pylori infection.MethodsThis study incorporated 527 GC patients and 441 controls from a cohort at Seoul National University Bundang Hospital. The associations between GC risk and single nucleotide polymorphisms were calculated, stratified by H. pylori status, adjusting for age, sex, and smoking. mRNA expression from non-cancerous gastric mucosae was evaluated using reverse transcription quantitative polymerase chain reaction.ResultsIn the entire cohort, genome-wide association study showed no significant variants reached the genome-wide significance level. In the H. pylori–positive group, rs2671655 (chr17:47,468,020;hg19, GH17J049387 enhancer region) was identified at a genome-wide significance level, which was more pronounced in diffuse type GC. There was no significant variant in the H. pylori–negative group, indicating the effect modification of rs2671655 by H. pylori. Among the target genes of GH17J049387 enhancer (PHB1, ZNF652 and SPOP), PHB1 mRNA was expressed more in cases than in controls, who were not affected by H. pylori. By contrast, an increase in ZNF652 and SPOP in GC was observed only in the H. pylori–negative group (P < 0.05). Mediation analysis showed that PHB1 (P = 0.0238) and SPOP (P = 0.0328) mediated the effect of rs2671655 on GC risk. The polygenic risk score was associated with the number of rs2671655 risk alleles only in the H. pylori–positive group (P = 0.0112).ConclusionAfter H. pylori infection, rs2671655 may increase GC risk, especially in diffuse-type GC, by regulating the expression of several genes that consequently modify susceptibility to GC.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10120-022-01285-x.

Heritable Variants in the Chromosome 1q22 Locus Increase Gastric Cancer Risk via Altered Chromatin Looping and Increased UBAP2L Expression.

Genome-wide association studies (GWAS) have implicated the 1q22 gastric cancer risk locus in disease, but little is known about its underlying oncogenic functions. This study represents a systematic investigation of the biological significance and potential mechanism associated with the gastric cancer risk of SNP rs2075570(C>T) in 1q22. We identified two functional germline variations (rs2049805-C and rs2974931-G) in an active enhancer in a 64.8 kb high-linkage disequilibrium block of rs2075570. The enhancer upregulated ubiquitin associated protein 2 like (UBAP2L) gene expression over a 960 kb distance by chromatin looping. Gastric cancer tissues expressed significantly higher levels of UBAP2L than was observed in the matched noncancerous tissues, and the UBAP2L expression was negatively correlated with patient survival. Downregulation of UBAP2L inhibited the proliferation and invasion of human gastric cancer cells in vitro and in a xenograft mouse model. Notably, the two mutant variations significantly enforced the enhancer activity and UBAP2L expression. In conclusion, this study revealed two causal variations in the 1q22 region using tag-SNP rs2075570 as a genetic marker. These variations may affect the occurrence and progression of gastric cancer by reinforcing the expression of the 1q22-Enh enhancer-regulated UBAP2L target gene. IMPLICATIONS: Our study provides an important clue of how noncoding germline variations contribute to gastric cancer, which gives a novel insight into understanding the genetic mechanism of gastric cancer.

Riboflavin intake, MTRR genetic polymorphism (rs1532268) and gastric cancer risk in a Korean population: a case-control study.

The vitamin B group, including riboflavin, plays paramount roles in one-carbon metabolism (OCM), and disorders related to this pathway have been linked to cancer development. The variants of genes encoding OCM enzymes and the insufficiency of B vitamins could contribute to carcinogenesis. Very few observational studies have revealed a relationship between riboflavin and gastric cancer (GC), especially under conditions of modified genetic factors. We carried out a study examining the association of riboflavin intake and its interaction with MTRR (rs1532268) genetic variants with GC risk among 756 controls and 377 cases. The OR and 95 % CI were evaluated using unconditional logistic regression models. We observed protective effects of riboflavin intake against GC, particularly in the female subgroup (OR = 0·52, 95 % CI 0·28, 0·97, Ptrend = 0·031). In the MTRR (rs1532268) genotypes analysis, the dominant model showed that the effects of riboflavin differed between the CC and CT + TT genotypes. Compared with CC carriers, low riboflavin intake in T+ carriers was significantly associated with a 93 % higher GC risk (OR = 1·93, 95 % CI 1·09, 3·42, Pinteraction = 0·037). In general, higher riboflavin intake might help reduce the risk of GC in both CC and TC + TT carriers, particularly the T+ carriers, with marginal significance (OR = 0·54, 95 % CI 0·28, 1·02, Pinteraction = 0·037). Our study indicates a protective effect of riboflavin intake against GC. Those who carry at least one minor allele and have low riboflavin intake could modify this association to increase GC risk in the Korean population.

GJA1 rs2071165 A > G Variant Increased Gastric Cancer Risk in Females of Northwest China: A Case-Control Study.

Gastric cancer (GC) is one of the most common malignancies, and its incidence rates vary widely between men and women. Previous studies have suggested that connexin 43 (Cx43, encoded by gap junction protein alpha 1 (GJA1)) and secretory carrier membrane protein 1 (SCAMP1) are key functional proteins in tumors. Herein, the association between GJA1 and SCAMP1 polymorphisms and GC susceptibility and prognosis was evaluated. A total of three single-nucleotide polymorphisms among 681GC patients and 756 controls were tested using the Agena MassARRAY RS1000 system, including GJA1 rs2071165, SCAMP1 rs4530741, and SCAMP1 rs6874309. The strength of the association with GC risk was assessed by the odds ratios (ORs) and 95% confidence intervals (CIs) generated from the logistic regression model. Kaplan–Meier curve, long-rank tests, and a multivariate Cox proportional hazard model were used for prognosis analysis. The expression of GJA1 was assessed by immunohistochemistry. The GJA1 rs2071165 AA/AG genotype significantly increased the risk of GC in the female Chinese population (OR = 1.55, 95% CI = 1.03–2.32, p=0.034). Furthermore, the risk effect of GJA1 rs2071165 was more evident in the subgroups of female patients with GC, stratified by age, clinical stage, tumor size, and recurrence/metastasis. However, no obvious differences in Cx43 expression in GC tissues were observed between males and females. Furthermore, no significant association between SCAMP1 rs4530741 and rs6874309 polymorphisms and GC risk or prognosis was observed. In conclusion, this study suggests for the first time that the GJA1 rs2071165 polymorphism is associated with increased GC risk in females, revealing a potential new clinical marker for assessing GC risk in females.

Association study between KCNQ1 and KCNQ1OT1 genetic polymorphisms and gastric cancer susceptibility and survival in a Chinese Han population: a case-control study.

BackgroundThe present study analyzed gene polymorphisms in the potassium voltage-gated channel KQT-like subfamily member 1 (KCNQ1) and the long noncoding RNA, KCNQ1OT1, and their impacts on genetic susceptibility and survival in a Chinese Han population with gastric cancer (GC).MethodsWe designed a case-control study that included 681 patients with GC and 756 healthy controls. Three single-nucleotide polymorphisms (SNPs) in the KCNQ1 gene region and eight SNPs in the KCNQ1OT1 gene region were selected for further research.ResultsAmong the 11 SNPs, we found no significant differences in the genotype and allele frequencies between GC patients and the healthy population. Hierarchical analysis by the log-additive model indicated that the KCNQ1 rs231348 CT genotype was significantly associated with an increased GC risk in individuals aged ≥55 years, regardless of gender. The KCNQ1OT1 rs231352 CC and rs7128926 AA genotypes increased the risk of GC in individuals with stage III/IV tumors larger than 5 cm in diameter. On evaluating the genotype polymorphism and survival analysis, we detected that the AA genotypes of the KCNQ1OT1 rs7128926 and rs7939976 polymorphisms presented a significant survival advantage over the GA/GG genotypes, especially in patients with the following characteristics: age >55, Helicobacter pylori infection, BMI >24, tumor in the non-cardia region with a diameter greater than 5 cm, clinical stage II, and postoperative adjuvant chemotherapy.ConclusionsOur results suggest that the KCNQ1 rs231348 and KCNQ1OT1 rs231352 polymorphisms might be independent predictors of the risk of GC susceptibility depending on certain factors, such as the age of the individual and the tumor stage and diameter. Simultaneously, genotype polymorphism of the rs7128926 and rs7939976 loci of the KCNQ1OT1 gene independently predicted the recurrence-free survival (RFS) and overall survival (OS) of GC patients.