Phospholipase C epsilon 1 (PLCE1) (an effector of Ras) belonging to the phospholipase family plays crucial roles in carcinogenesis and progression of several cancers, including squamous cell carcinoma of the head and neck (SCCHN). A single nucleotide polymorphism (SNP, rs2274223) in PLCE1 has been identified as a novel susceptibility locus in genome-wide association studies (GWAS) of esophageal squamous cell carcinoma (ESCC) and gastric cardia adenocarcinoma (GCA) that share similar risk factors with SCCHN. Therefore, we investigated the association between potentially functional SNPs in PLCE1 and susceptibility to SCCHN.
We genotyped three potentially functional SNPs (rs2274223A/G, rs3203713A/G and rs11599672T/G) of PLCE1 in 1,098 SCCHN patients and 1,090 controls matched by age and sex in a non-Hispanic white population.
Although none of three SNPs was alone significantly associated with overall risk of SCCHN, their combined effects of risk alleles (rs2274223G, rs3203713G and rs11599672G) were found to be associated with risk of SCCHN in a locus-dose effect manner (Ptrend = 0.046), particularly for non-oropharyngeal tumors (Ptrend = 0.017); specifically, rs2274223 was associated with a significantly increased risk (AG vs. AA: adjusted OR = 1.29, 95% CI = 1.01-1.64; AG/GG vs. AA: adjusted OR = 1.30, 95% CI = 1.03-1.64), while rs11599672 was associated with a significantly decreased risk (GG vs. TT: adjusted OR = 0.54, 95% CI = 0.34-0.86; TG/GG vs. TT: adjusted OR = 0.76, 95% CI = 0.61-0.95).
Our findings suggest that PLCE1 variants may have an effect on risk of SCCHN associated with tobacco and alcohol exposure, particularly for those tumors arising at non-oropharyngeal sites. These findings, although need to be validated by larger studies, are consistent with those in esophageal and gastric cancers.
PLCE1; polymorphism; SCCHN; risk; susceptibility
In recent years, the PLCE1 rs2274223 polymorphism has been extensively investigated as a potential risk factor for upper gastrointestinal cancers, including squamous cell carcinoma (ESCC) and gastric cancer. However, the results of these studies have been inconsistent.
A meta-analysis of 13 case-control studies was performed including more than 11,000 subjects with genotyped PLCE1 rs2274223 polymorphisms. Odds ratios (OR) with 95% confidence intervals (CI) were employed to assess the association of the PLCE1 rs2274223 polymorphism with a susceptibility to ESCC or gastric cancer.
A statistically significant increase in the risk of ESCC was associated with the PLCE1 rs2274223 polymorphism. This included the homozygous genetic model (OR = 1.46), heterozygous genetic model (OR = 1.25) and allelic genetic model (OR = 1.23). Similar results were consistently found for gastric cancer. In a subgroup analysis, the PLCE1 rs2274223 polymorphism was found to be a very sensitive marker for gastric cardia cancer as shown by the homozygous genetic model (OR = 2.23), heterozygous genetic model(OR = 1.59) and allelic genetic model (OR = 1.47). The risk associations of all of the gastric cardia cancer models were statistically significant. In contrast, none of the genetic models for non-cardia gastric cancer were significant.
In this meta-analysis, the PLCE1 rs2274223 polymorphism was confirmed to have a statistically significant association with an increasing risk of ESCC and gastric cancer. The increase risk was especially observed for gastric cardia cancer.
Background And Objective
Two recent genome-wide association studies have identified a shared susceptibility variation PLCE1 rs2274223 for esophageal squamous cell carcinoma (ESCC) and gastric cardia adenocarcinomas (GCA). Subsequent case-control studies have reported this association in other populations. However, the findings were controversial and the effect remains undetermined. Our aim is to provide a precise quantification of the association between PLCE1 rs2274223 variation and the risk of ESCC and GCA.
Studies were identified by a literature search in MEDLINE and EMBASE databases. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the association in allele, dominant, recessive, homozygous, and heterozygous models.
Ten articles were identified, including 22156 ESCC cases and 28803 controls, 5197 GCA cases and 17613 controls. Overall, PLCE1 rs2274223 G allele (G vs. A: OR=1.26, 95% CI: 1.15-1.39 for ESCC; OR=1.51, 95% CI: 1.35–1.69 for GCA) and its carrier (GG +AG vs. AA: OR = 1.23; 95% CI =1.02-1.49 for ESCC; OR =1.62; 95% CI =1.15-2.29 for GCA) were significantly associated with the risk of ESCC and GCA. In stratified analysis by ethnicity, significant association of PLCE1 rs2274223 G allele and the risk of ESCC (OR=1.33, 95% CI 1.21–1.45) and GCA (OR =1.56, 95% CI: 1.47-1.64) was observed in Chinese population.
Our meta-analysis results indicated that PLCE1 rs2274223 G allele significantly contributed to the risk of ESCC and GCA, especially in Chinese population.
To date, the association between phospholipase C epsilon 1 (PLCE1) rs2274223 A>G and risk of digestive tract cancer (DTC) remains inconclusive. To derive a more precise estimation of the association, we conducted a meta-analysis on all eligible case–control studies involving 8281 cases and 10,532 controls.
A comprehensive search was conducted to identify all eligible studies of PLCE1 rs2274223 polymorphism and digestive tract cancer risk. The pooled odds ratio (OR) and the 95% confidence interval (95% CI) were calculated using a fixed or random effect model. Heterogeneity, publication bias, and sensitivity analysis were also explored.
Overall, the PLCE1 rs2274223 A>G polymorphism was associated with risk of DTC in all genetic models (GA vs. AA: OR = 1.21, 95% CI = 1.14–1.29, P<0.001; GG vs. AA: OR = 1.30, 95% CI = 1.06–1.60, P = 0.012; GG/GA vs. AA: OR = 1.20, 95% CI = 1.10–1.32, P<0.001; GG vs. GA/AA: OR = 1.21, 95% CI = 1.01–1.46, P = 0.040). The recessive model did not reach statistically significance when the P values were Bonferroni corrected to 0.0125. In the stratified analysis by cancer type, ethnicity, and source of controls, significantly increased risk was observed for esophagus cancer, Asians in three genetic models (heterozygote comparison, homozygote comparison and dominant model), population-based studies in all genetic models, and for gastric cancer in the heterozygote comparison and dominant model after Bonferroni correction. However, in the subsite of gastric cancer, no significant association was found either in cardia or non-cardia gastric cancer.
Our study indicated that PLCE1 rs2274223 A>G polymorphism was significantly associated with increased risk of DTC, especially among Asian populations. Due to some minor limitations, our findings should be confirmed in further studies.
Phospholipase C epsilon 1 (PLCE1) plays a crucial role in carcinogenesis and progression of several types of cancers. A single nucleotide polymorphism (SNP, rs2274223) in PLCE1 has been identified as a novel susceptibility locus. The aim of the present study was to investigate the role of three potentially functional SNPs (rs2274223A > G, rs3765524C > T, and rs7922612C > T) of PLCE1 in gastric cancer patients from Kashmir Valley.
Patients and Methods:
The study was conducted in 108 GC cases and 195 healthy controls from Kashmir Valley. Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism method. Data were statistically analyzed using χ2 test and logistic regression models. A P value of less than 0.05 was regarded as statistically significant.
The frequency of PLCE1 A2274223C3765524T7922612, G2274223C3765524T7922612, and G2274223T3765524C7922612 haplotypes were higher in patients compared with controls, conferred high risk for GC [odds ratio (OR) =6.29; P = 0.001; Pcorr = 0.003], (OR = 3.23; P = 0.011; Pcorr = 0.033), and (OR = 5.14; P = 0.011; Pcorr = 0.033), respectively. Smoking and salted tea are independent risk factors for GC, but we did not find any significant modulation of cancer risk by PLCE1 variants with smoking or excessive consumption of salted tea.
These results suggest that variation in PLCE1 may be associated with GC risk in Kashmir Valley.
Gastric cancer; Kashmir Valley; haplotype; PLCE1 and PCR-RFLP
Three recent genome-wide association studies (GWASs) have reported that three SNPs (rs4072037, rs13361707 and rs2274223) located on genes related to host inflammatory response are significantly associated with susceptibility to gastric cancer (GC) in Chinese populations. Helicobacter pylori infection is also an important risk factor for GC through causing inflammatory response in the gastric mucosa. However, no study has established whether there are potential gene-environment interactions between these genetic variants and H. pylori infection to the risk of GC.
We genotyped three polymorphisms (rs4072037 at 1q22, rs13361707 at 5p13, and rs2274223 at 10q23) in 335 Chinese gastric adenocarcinoma patients and 334 controls. H. pylori serology was examined by enzyme-linked immunosorbent assay. Multivariable logistic regression models were used to evaluate the association between the variables and GC risk.
We confirmed that the three SNPs (rs4072037, rs13361707 and rs2274223) were significantly associated with GC susceptibility. H. pylori infection also significantly increased the risk of GC. Furthermore, there were joint effects between H. pylori infection and the three SNPs on the risk of GC. The most elevated risk of GC was found in subjects with H. pylori seropositivity and AA genotypes for rs4072037 [odds ratio (OR), 3.95; 95% confidence interval (CI), 2.29–6.79], H. pylori seropositivity and CT/CC genotypes for rs13361707 (OR, 2.68; 95% CI, 1.62–4.43), H. pylori seropositivity and AG/GG genotypes for rs2274223 (OR, 2.45; 95% CI, 1.55–3.88) compared with those with H. pylori seronegativity and other genotypes of each SNP. Significant interactions were observed between H. pylori seropositivity and the three SNPs (all PG× E <0.05) to the risk of GC.
These findings indicate that the three SNPs (rs4072037, rs13361707 and rs2274223) identified in the GWASs may interact with H. pylori infection to increase the risk of GC.
Several genetic variants including PSCA rs2294008 C>T and rs2976392 G>A, MUC1 rs4072037 T>C, and PLCE1 rs2274223 A>G have shown significant association with stomach cancer risk in the previous genome-wide association studies (GWASs).
To evaluate associations of these SNPs in the Han Chinese, an independent hospital based case-control study was performed by genotyping these four polymorphisms in a total of 692 stomach cancer cases and 774 healthy controls acquired by using frequency matching for age and gender. False-positive report probability (FPRP) analysis was also performed to validate all statistically significant findings.
In the current study, significant association with stomach cancer susceptibility was observed for all the four polymorphisms of interest. Specifically, a significant increased stomach cancer risk was associated with PSCA rs2294008 (CT vs. CC: adjusted OR = 1.37, 95% CI = 1.07–1.74, and CT/TT vs.CC: adjusted OR = 1.30, 95% CI = 1.03–1.63), PSCA rs2976392 (AG vs. GG: adjusted OR = 1.30, 95% CI = 1.02–1.65, and AG/AA vs. GG: adjusted OR = 1.26, 95% CI = 1.00–1.59), or PLCE1 rs2274223 (AG vs. AA: adjusted OR = 1.48, 95% CI = 1.15–1.90, and AG/GG vs. AA: adjusted OR = 1.45, 95% CI = 1.14–1.84), respectively. In contrast, MUC1 rs4072037 was shown to decrease the cancer risk (CT vs. TT: adjusted OR = 0.77, 95% CI = 0.60–0.98). Patients with more than one risk genotypes had significant increased risk to develop stomach cancer (adjusted OR = 1.30, 95% CI = 1.03–1.64), when compared with those having 0–1 risk genotypes. Stratified analysis indicated that the increased risk was more pronounced in younger subjects, men, ever smokers, smokers with pack years ≤ 27, patients with high BMI, or non-cardia stomach cancer.
This study substantiated the associations between four previous reported genetic variants and stomach cancer susceptibility in an independent Han Chinese population. Further studies with larger sample size and different ethnicities are warranted to validate our findings.
Recently, two large genome wide association studies, conducted in Chinese populations, reported associations between upper gastrointestinal (GI) cancer and the rs2274223, rs13042395 and rs4072037 polymorphisms in PLCE1, C20orf54 and MUC1 respectively. We set out to determine whether similar associations existed for Caucasian populations.
We genotyped two population-based, case-control studies of upper GI cancer; the first included 290 gastric cancer cases and 376 controls; the second study included 306 gastric cancer cases, 107 oesophageal adenocarcinoma cancer cases, 52 oesphageal squamous cell cancer cases, and 211 controls. Odds ratios (OR) and 95% confidence intervals (CI) were computed from logistic models and adjusted for confounding variables.
The rs4072037 polymorphism in MUC1 was associated with a reduced risk of gastric cancer of intestinal histological type (OR 0.4; 95% CI 0.2–0.9), and a reduced risk of oesophageal squamous cell cancer (OR 0.5; 95% CI 0.2–1.0), but not oesphageal adenocarcinoma. Likewise, rs2274223 in PLCE1 was associated with a reduced risk of oesophageal squamous cell cancer (OR 0.5; 95% CI 0.3–1.0) but not oesphageal adenocarcinoma. We observed no association between rs13042395 in Corf54 and risk of gastric or oesphageal cancer in either of the two studies.
Our findings for rs4072037 and gastric cancer risk are in keeping with one previous report for a Caucasian population. To the best of our knowledge this is the first study to report an association between rs2274223 and rs4072037 and risk of oesophageal squamous cell carcinoma in a Caucasian population.
Two recent genome-wide association studies reported significant associations of genetic variants at 1q22, 10q23 and 20p13 with gastric cancer (GC) risk in Chinese populations. However, these findings have not been confirmed in other independent studies. Here, we performed an independent case–control study in a Chinese population by genotyping three loci (rs4072037A>G at 1q22, rs2274223A>G at 10q23 and rs13042395C>T at 20p13) in 1681 GC cases and 1858 controls. We found that rs4072037 at 1q22 and rs2274223 at 10q23 were significantly associated with risk of GC with per allele odds ratio (OR) of 0.72 [95% confidence interval (CI): 0.63–0.81; P = 2.98 × 10−7] and 1.42 (95% CI: 1.27–1.58; P = 9.68 × 10−10), respectively. The association was more prominent for rs2274223 in female (OR = 1.86, 95% CI: 1.49–2.32) and gastric cardia adenocarcinoma (GCA) (OR = 1.71, 95% CI: 1.49–1.95). Furthermore, we combined the two single-nucleotide polymorphisms to evaluate the joint effect and found that the GC risk significantly increased with the number of risk allele increasing with a trend P value of 6.66 × 10−16, and individuals with four risk alleles had a 3.28-fold (95% CI: 1.75–6.13) risk of GC compared with those having no risk alleles. However, no significant association was detected between rs13042395 at 20p13 and GC risk (OR = 1.04, 95% CI: 0.94–1.15; P = 0.452). In conclusion, our results indicate that genetic variants at 1q22 and 10q23 but not 20p13 may serve as candidate markers for GC susceptibility in the Chinese population.
We previously showed that human papillomavirus (HPV) serostatus was not an independent risk factor for esophageal squamous cell carcinoma(ESCC) in nonsmokers and nondrinkers; however, HPV increased the risk in smokers.
Here we investigated possible interactions between HPV16 serostatus and three susceptibility loci identified in GWASs at apoptosis associated genes with regard to risk of ESCC in a case–control study of 313 patients with ESCC and 314 healthy controls. The loci (CHK2 rs738722, C12orf51 rs2074356, and PLCE1 rs2274223) were genotyped, and the presence or absence of HPV16 in serum was measured by ELISA. Multivariable logistic regression was used to evaluate possible interactions of HPV16 serostatus and the three loci on the risk of ESCC.
A significant interaction was found between HPV16 serology and rs2074356 (P = 0.005, odds ratio [OR] 1.40, 95% confidence interval [CI] 1.11–1.77) or rs2274223 (P < 0.001, OR 1.53, 95% CI 1.23–1.91), but not for rs738722. For rs2074356, risk of ESCC was increased substantially in smokers (P < 0.001, OR 8.25, 95% CI 3.84–17.71) and drinkers (OR4.04, P = 0.001, 95% CI 1.79–9.10) who carried risk alleles (TT or TC genotype) and were HPV16-seropositive. Similar results were observed for rs2274223 in smokers (P < 0.001, OR6.06, 95% CI 2.85–12.88) and drinkers (P < 0.001, OR 5.43, 95% CI 2.51–11.76), but not for rs738722.
Consistent with the previous study, loci at rs2074356 and rs2274223 could increase the risk of ESCC, furthermore, there were significant interactions between HPV sero-status and the susceptibility loci on the risk of ESCC. This effect could be modified obviously by smoking and drinking.
Esophageal squamous cell carcinoma; Apoptosis; Genome-wide association study; HPV16; Single nucleotide polymorphism; Smoking; Drinking
We conducted a genome-wide association study of gastric cancer (GC) and esophageal squamous cell carcinoma (ESCC) in ethnic Chinese subjects in which we genotyped 551,152 single nucleotide polymorphisms (SNPs). We report a combined analysis of 2,240 GC cases, 2,115 ESCC cases, and 3,302 controls drawn from five studies. In logistic regression models adjusted for age, sex, and study, multiple variants at 10q23 had genome-wide significance for GC and ESCC independently. A notable signal was rs2274223, a nonsynonymous SNP located in PLCE1, for GC (P=8.40×10−9; per allele odds ratio (OR) = 1.31) and ESCC (P=3.85×10−9; OR = 1.34). The association with GC differed by anatomic subsite. For tumors located in the cardia the association was stronger (P=4.19 × 10−15; OR= 1.57) and for those located in the noncardia stomach it was absent (P=0.44; OR=1.05). Our findings at 10q23 could provide insight into the high incidence rates of both cancers in China.
We conducted a genome-wide association study of gastric cancer (GC) and esophageal squamous cell carcinoma (ESCC) in ethnic Chinese subjects in which we genotyped 551,152 single nucleotide polymorphisms (SNPs). We report a combined analysis of 2,240 GC cases, 2,115 ESCC cases, and 3,302 controls drawn from five studies. In logistic regression models adjusted for age, sex, and study, multiple variants at 10q23 had genome-wide significance for GC and ESCC independently. A notable signal was rs2274223, a nonsynonymous SNP located in PLCE1, for GC (P=8.40×1010; per allele odds ratio (OR) = 1.31) and ESCC (P=3.85×10−9; OR = 1.34). The association with GC differed by anatomic subsite. For tumors located in the cardia the association was stronger (P=4.19 × 10−15; OR= 1.57) and for those located in the noncardia stomach it was absent (P=0.44; OR=1.05). Our findings at 10q23 could provide insight into the high incidence rates of both cancers in China.
Phospholipase C epsilon 1 (PLCE1) plays an important role in cell growth, differentiation and oncogenesis. An increasing number of individual studies have investigated the association between PLCE1 rs2274223 polymorphism and cancer risk, but the conclusions are inconclusive. To obtain a comprehensive conclusion, we performed a meta-analysis of 22 studies with 13188 cases and 14666 controls. The pooled results indicated that PLCE1 rs2274223 A > G polymorphism was associated with an increased risk of overall cancer (G vs. A: OR = 1.15, 95% CI = 1.06–1.25; GG vs. AA: OR = 1.30, 95% CI = 1.10–1.55; GA vs. AA: OR = 1.18, 95% CI = 1.08–1.30; GG/GA vs. AA: OR = 1.20, 95% CI = 1.08–1.32; GG vs. GA/AA: OR = 1.22, 95% CI = 1.04–1.42). The stratification analysis showed the polymorphism was significantly associated with an increased risk of esophageal squamous cell carcinoma (ESCC) other than gastric cancer (GC), especially among the subgroups of Asian, high quality score, sample size > 1000 and the studies consistent with Hardy-Weinberg equilibrium (HWE). This meta-analysis demonstrated that PLCE1 rs2274223 A > G polymorphism may be associated with increased susceptibility to cancer, especially for ESCC. However, due to the substantial heterogeneities across the studies, the conclusion might be not conclusive that need more studies to confirm.
A recent genome-wide association study (GWAS) identified susceptibility loci for dengue shock syndrome (DSS) at MICB rs3132468 and PLCE1 rs3740360. The aim of this study was to define the extent to which MICB (rs3132468) and PLCE1 (rs3740360) were associated with less severe clinical phenotypes of pediatric and adult dengue.
3961 laboratory-confirmed dengue cases and 5968 controls were genotyped at MICB rs3132468 and PLCE1 rs3740360. Per-allele odds ratios (OR) with 95% confidence intervals (CI) were calculated for each patient cohort. Pooled analyses were performed for adults and paediatrics respectively using a fixed effects model.
Pooled analysis of the paediatric and adult cohorts indicated a significant association between MICB rs3132468 and dengue cases without shock (OR = 1.15; 95%CI: 1.07 – 1.24; P = 0.0012). Similarly, pooled analysis of pediatric and adult cohorts indicated a significant association between dengue cases without shock and PLCE1 rs3740360 (OR = 0.92; 95%CI: 0.85 – 0.99; P = 0.018). We also note significant association between both SNPs (OR = 1.48; P = 0.0075 for MICB rs3132468 and OR = 0.75, P = 0.041 for PLCE1 rs3740360) and dengue in infants.
This study confirms that the MICB rs3132468 and PLCE1 rs3740360 risk genotypes are not only associated with DSS, but are also associated with less severe clinical phenotypes of dengue, as well as with dengue in infants. These findings have implications for our understanding of dengue pathogenesis.
Oesophageal squamous cell carcinoma (OSCC) has a high prevalence in the Black and Mixed Ancestry populations of South Africa. Recently, three genome-wide association studies in Chinese populations identified five new OSCC susceptibility loci, including variants at PLCE1, C20orf54, PDE4D, RUNX1 and UNC5CL, but their contribution to disease risk in other populations is unknown. In this study, we report testing variants from these five loci for association with OSCC in the South African Black (407 cases and 849 controls) and Mixed Ancestry (257 cases and 860 controls) populations. The RUNX1 variant rs2014300, which reduced risk in the Chinese population, was associated with an increased risk of OSCC in the Mixed Ancestry population [odds ratio (OR) = 1.33, 95% confidence interval (CI) = 1.09–1.63, P = 0.0055], and none of the five loci were associated in the Black population. Since PLCE1 variants increased the risk of OSCC in all three Chinese studies, this gene was investigated further by sequencing in 46 Black South Africans. This revealed 48 variants, 10 of which resulted in amino acid substitutions, and much lower linkage disequilibrium across the PLCE1 locus than in the Chinese population. We genotyped five PLCE1 variants in cases and controls, and found association of Arg548Leu (rs17417407) with a reduced risk of OSCC (OR = 0.74, 95% CI = 0.60–0.93, P = 0.008) in the Black population. These findings indicate several differences in the genetic contribution to OSCC between the South African and Chinese populations that may be related to differences in their genetic architecture.
Caspase 7 (CASP7) is an important regulator and executioner in the apoptosis pathway and plays a crucial role in cancer development and progression. However, few studies have evaluated associations between functional single nucleotide polymorphisms (SNPs) in the 3′ untranslational region (UTR) of CASP7 and risk of gastric cancer.
In a case-control study of 1117 patients with gastric cancer and 1146 cancer-free controls with frequency matching on age and sex, we genotyped four potentially functional SNPs (rs4353229T>C, rs10787498T>G, rs1127687G>A and rs12247479G>A) located in the microRNA binding sites of the CASP7 3′ UTR by using Taqman assays and evaluated their associations with risk of gastric cancer by using logistic regression analyses as well as multifactorial dimension reduction (MDR) analysis.
In the single-locus analysis, only the CASP7 rs4353229 TT genotype was associated with 0.83-fold decreased risk (95% confidence interval [CI] = 0.70–0.98) of gastric cancer under a recessive model, compared with the CT/CC genotypes. In the combined analysis of all four SNPs, we found that the risk of gastric cancer decreased by 19% in those carrying any of the risk genotypes (adjusted odds ratio = 0.81, 95% CI = 0.68–0.96), compared with those carrying zero risk genotypes, and this risk was more evident in subgroups of younger age (<59 years), females, non-smokers, non-drinkers and patients with non-gastric cardia adenocarcinoma. Further MDR analysis suggested some evidence of interactions between the combined genotypes and other risk factors for gastric cancer.
Potentially functional CASP7 variants may contribute to risk of gastric cancer. Larger studies with different ethnic populations are warranted to validate our findings.
Dengue shock syndrome (DSS), a severe life-threatening form of dengue infection, mostly occurs in children. A recent genome wide association study (GWAS) identified two SNPs, rs3132468 of major histocompatibility complex class I polypeptide-related sequence B (MICB) and rs3765524 of phospholipase C, epsilon 1 (PLCE1), associated with DSS in Vietnamese children. In this study, to examine whether an identical association is found in a different population, the association of these two SNPs with DSS was assessed in Thai children with dengue.
The rs3132468 and rs3765524 SNPs were genotyped in 917 Thai children with dengue: 76 patients with DSS and 841 patients with non-DSS. The allele frequencies were compared between DSS and non-DSS groups by one-sided Fisher’s exact test. The association of rs3132468 and rs3765524 with the mRNA expression levels of MICB and PLCE1 were assessed in EBV-transformed lymphoblastoid cell lines.
The reported DSS-risk alleles were significantly associated with DSS in Thai patients with dengue (one-sided P = 0.0213 and odds ratio [OR] = 1.58 for rs3132468-C and one-sided P = 0.0252 and OR = 1.49 for rs3765524-C). The rs3132468-C allele showed a significant association with lower mRNA level of MICB (P = 0.0267), whereas the rs3765524-C allele did not. These results imply that the MICB molecule may play an important role in the prevention of DSS in dengue infection.
Together with previous association studies, we conclude that rs3132468-C at MICB and rs3765524-C at PLCE1 confer risk of DSS in Southeast Asians.
Association; Dengue shock syndrome (DSS); Expression; MICB; PLCE1; Polymorphism
Inherited functional single nucleotide polymorphisms (SNPs) in DNA repair genes may alter DNA repair capacity and thus contribute to cancer risk.
Three ERCC1 functional SNPs (rs2298881C>A, rs3212986C>A and rs11615G>A) and two XPF/ERCC4 functional SNPs (rs2276466C>G and rs6498486A>C) were genotyped for 1125 gastric adenocarcinoma cases and 1196 cancer-free controls by Taqman assays. Odds ratios (OR) and 95% confidence intervals (CI) were used to estimate risk associations, and false-positive report probabilities (FPRP) were calculated for assessing significant findings.
ERCC1 rs2298881C and rs11615A variant genotypes were associated with increased gastric cancer risk (adjusted OR = 1.33, 95% CI = 1.05–1.67 for rs2298881 AC/CC and adjusted OR = 1.23, 95% CI = 1.05–1.46 for rs11615 AG/AA, compared with their common genotype AA and GG, respectively). Patients with 2–3 ERCC1 risk genotypes had significant increased risk (adjusted OR = 1.56, 95% CI = 1.27–1.93), compared with those with 0–1 ERCC1 risk genotypes, and this risk was more significantly in subgroups of never drinkers, non-gastric cardia adenocarcinoma (NGCA) and clinical stage I+II. All these risks were not observed for XPF SNPs.
These findings suggest that functional ERCC1 SNPs may contribute to risk of gastric cancer. Larger and well-designed studies with different ethnic populations are needed to validate our findings.
In a population-based case-control study in the U.S., we examined risks of histologically confirmed esophageal and gastric adenocarcinomas in relation to polymorphisms of the following genes: GSTP; GSTM1; GSTT1; NAT1; and CYP1A1. For the GSTP1 Val/Val genotype (vs. Ile/Ile), the respective ORs of esophageal, cardia, and other gastric adenocarcinomas were 1.73 (0.75–4.02), 1.46 (0.57–3.73), and 1.22 (0.48–3.09), while no consistent patterns of elevated risk were associated with the null GSTM1 or GSTT1 genotypes, one or two copies of NAT1*10 or *11 alleles, or CYP1A1 Val/Val or Ile/Val genotypes (vs. Ile/Ile).
Polymorphisms in glutathione-S-transferase (GST), N-acetyltransferase (NAT) 1, and CYP1A1 genes have been suggested as susceptibility factors for esophageal and gastric adenocarcinomas, but have not been consistently linked to elevated risks. In a population-based case-control study, we examined risks in relation to polymorphisms of the following genes: GSTP; GSTM1; GSTT1; NAT1; and CYP1A1.
Histologically confirmed incident cases, ages 30–79, were identified in three U.S. locations. Population controls from the same catchment areas were frequency matched to expected age and sex distributions of esophageal and gastric cardia adenocarcinomas. DNA was extracted from buffy coat for PCR-based assays, with interpretable genotyping results obtained from 209 controls, 67 esophageal adenocarcinomas, 60 gastric cardia adenocarcinomas, and 56 noncardia gastric adenocarcinomas. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated among whites, adjusting for age, sex, and study center.
In all histologic subgroups, ORs were somewhat elevated for the GSTP1 Val/Val genotype (vs. Ile/Ile), although 95% CIs included 1.00. The respective ORs for esophageal, cardia, and other gastric adenocarcinomas were 1.73 (0.75–4.02), 1.46 (0.57–3.73), and 1.22 (0.48–3.09). No consistent patterns of elevated risk were associated with the null GSTM1 or GSTT1 genotypes, one or two copies of NAT1*10 or *11 alleles, or CYP1A1 Val/Val or Ile/Val genotypes (vs. Ile/Ile).
Additional research in larger samples is needed to further assess polymorphisms and their interactions with epidemiologic risk factors, particularly for esophageal adenocarcinoma, which has been increasing markedly in incidence.
polymorphism; genetic; cancer risk; gastrointestinal cancer; adenocarcinoma; esophageal; adenocarcinoma; gastric; epidemiology
Hereditary hemochromatosis (HH) is a strong risk factor for hepatocellular cancer, and mutations in the HFE gene associated with HH and iron overload may be related to other tumors, but no studies have been reported for gastric cancer (GC). A nested case–control study was conducted within the European Prospective Investigation into Cancer and Nutrition (EPIC), including 365 incident gastric adenocarcinoma and 1284 controls matched by center, sex, age and date of blood collection. Genotype analysis was performed for two functional polymorphisms (C282Y/rs1800562 and H63D/rs1799945) and seven tagSNPs of the HFE genomic region. Association with all gastric adenocarcinoma, and according to anatomical localization and histological subtype, was assessed by means of the odds ratio (OR) and 95% confidence interval (CI) estimated by unconditional logistic regression adjusted for the matching variables. We observed a significant association for H63D with OR (per rare allele) of 1.32 (CI = 1.03–1.69). In subgroup analyses, the association was stronger for non-cardia anatomical subsite (OR = 1.60, CI = 1.16–2.21) and intestinal histological subtype (OR = 1.82, CI = 1.27–2.62). Among intestinal cases, two tagSNPs (rs1572982 and rs6918586) also showed a significant association that disappeared after adjustment for H63D. No association with tumors located in the cardia or with diffuse subtype was found for any of the nine SNPs analyzed. Our results suggest that H63D variant in HFE gene seems to be associated with GC risk of the non-cardia region and intestinal type, possibly due to its association with iron overload although a role for other mechanisms cannot be entirely ruled out.
Gastric cancer including the cardia and non-cardia types is the second frequent cause of cancer-related deaths worldwide. A subset of non-cardia gastric cancer genetic susceptibility loci have been addressed among Asian through genome-wide association studies (GWASs). This study was to evaluate the effects of single nucleotide polymorphisms (SNPs) of long intergenic non-coding RNAs (lincRNAs) on non-cardia gastric cancer susceptibility in Chinese populations. We selected long intergenic noncoding RNAs (lincRNAs) located in non-cardia gastric cancer risk-related loci and identified 10 SNPs located within lincRNA exonic regions. We examined whether genetic polymorphisms in lincRNAs exons are associated with non-cardia gastric cancer risk in 438 non-cardia gastric cancer patients and 727 control subjects in Chinese populations using logistic regression. Functional relevance was further examined by biochemical assays. We found that lincRNA-NR_024015 rs8506AA carrier was significantly associated with risk of non-cardia gastric cancer (adjusted odds ratio [OR] = 1.56, 95%CI = 1.03–2.39, compared with the rs8506 AG or GG genotype. Further stratification analysis showed that the risk effect was more pronounced in subgroups of smokers (P = 0.001). Biochemical analysis demonstrated that the G to A base change at rs8506G>A disrupts the binding site for has-miR-526b, thereby influencing the transcriptional activity of lincRNA-NR_024015 and affecting cell proliferation. Our present study established a robust association between the rs8506G>A polymorphism in the lincRNA-NR_024015 exon and the risk of non-cardia gastric cancer.
Incidence of esophageal adenocarcinoma (EAC) has increased rapidly over the past forty years and accumulating evidence suggests that obesity, as measured by body mass index (BMI), is a major risk factor. However, it remains unclear whether abdominal obesity is associated with esophageal and gastric adenocarcinoma.
Cox proportional hazards regression was used to examine associations between overall and abdominal obesity with EAC and gastric adenocarcinoma among 218,854 participants in the prospective NIH-AARP cohort.
253 incident EAC, 191 gastric cardia adenocarcinomas, and 125 gastric non-cardia adenocarcinomas accrued to the cohort. Overall obesity (BMI) was positively associated with EAC and gastric cardia adenocarcinoma risk (highest [≥35 kg/m2] versus referent [18.5–<25 kg/m2]; hazard ratio (HR) 95% confidence interval (95% CI); 2.11 (1.09–4.09) and 3.67 (2.00–6.71), respectively). Waist circumference was also positively associated with EAC and gastric cardia adenocarcinoma risk, (highest versus referent; HR (95% CI) 2.01 (1.35–3.00) and 2.22 (1.43–3.47), respectively), whereas waist-to-hip ratio (WHR) was positively associated with EAC risk only (highest versus referent; HR (95% CI) 1.81 (1.24–2.64)); persisted in patients with normal BMI (18.5–<25 kg/m2). Mutual adjustment of WHR and BMI attenuated both, but did not eliminate the positive associations for either with risk of EAC. In contrast, the majority of the anthropometric variables were not associated with adenocarcinomas of the gastric non-cardia.
Overall obesity was associated with a higher risk of EAC and gastric cardia adenocarcinoma, whereas abdominal obesity was found to be associated with increased EAC risk; even in people with normal BMI.
adenocarcinoma; epidemiology; esophageal cancer; gastric adenocarcinoma; obesity
Incidence rates for adenocarcinomas of the esophagus and gastric cardia have been increasing rapidly, while rates for non-cardia gastric adenocarcinoma and esophageal squamous cell carcinoma have declined. We examined food group intake as a risk factor for subtypes of esophageal and gastric cancers in a multi-center, population-based case-control study in Connecticut, New Jersey, and western Washington state. Associations between food groups and risk were estimated using adjusted odds ratios (OR), based on increasing intake of one serving per day. Total vegetable intake was associated with decreased risk of esophageal adenocarcinoma (OR = 0.85, 95% CI = 0.75, 0.96). Conversely, total meat intake was associated with increased risk of esophageal adenocarcinoma (OR = 1.43, 95% CI = 1.11, 1.83), gastric cardia adenocarcinoma (OR = 1.37, 95% CI = 1.08, 1.73), and non-cardia gastric adenocarcinoma (OR = 1.39, 95% CI = 1.12, 1.71), with red meat most strongly associated with esophageal adenocarcinoma risk (OR = 2.49, 95% CI = 1.39, 4.46). Poultry was most strongly associated with gastric cardia adenocarcinoma (OR = 1.89, 95% CI = 1.15, 3.11) and non-cardia gastric adenocarcinoma (OR = 1.90, 95% CI = 1.19, 3.03). High-fat dairy was associated with increased risk of both esophageal and gastric cardia adenocarcinoma. Higher intake of meats, particularly red meats, and lower intake of vegetables were associated with an increased risk of esophageal adenocarcinoma, while higher intake of meats, particularly poultry, and high-fat dairy was associated with increased risk of gastric cardia adenocarcinoma.
Esophageal neoplasms; gastric neoplasms; food groups; case-control
In the last decades, the incidence of oesophageal and gastric cardia adenocarcinoma has increased rapidly in the Western world. We investigated the association between body mass index (BMI), height and risk of oesophageal and gastric cardia adenocarcinoma.
The Netherlands Cohort Study was initiated in 1986. All participants (n = 120 852), aged 55–69 years, completed a self administered questionnaire. Cases were identified through annual record linkage with the Netherlands Cancer Registry. After 13.3 years of follow‐up, excluding the first follow‐up year, complete data from 4552 subcohort members, 133 oesophageal and 163 gastric cardia adenocarcinomas were available for case‐cohort analyses. Incidence rate ratios (RRs) and corresponding 95% confidence intervals were estimated using Cox proportional hazard models.
The RRs (95% CI) of oesophageal adenocarcinoma were 1.40 (0.95 to 2.04) and 3.96 (2.27 to 6.88) for overweight (BMI 25.0–29.9 kg/m2) and obese subjects (BMI ⩾30.0 kg/m2), respectively, compared to subjects with normal weight (BMI 20.0–24.9 kg/m2). For gastric cardia adenocarcinoma, these RRs were 1.32 (0.94 to 1.85) and 2.73 (1.56 to 4.79). Also change in BMI during adulthood was positively associated with the risk of oesophageal and gastric cardia adenocarcinoma (p trend 0.001 and 0.02, respectively), while no association was found with BMI in early adulthood (p trend 0.17 and 0.17, respectively). None of the tumour types investigated was significantly associated with height.
These results confirm higher risks of oesophageal and gastric cardia adenocarcinoma with increasing BMI. This implies that the increasing prevalence of obesity may be one of the explanations for the rising incidence of oesophageal and gastric cardia adenocarcinoma in the Western world.
cohort study; oesophageal cancer; stomach cancer; risk factors; body mass index
The purpose of this study was to determine the genotype and allele frequencies of hMLH1 (-93G>A and I219V) and hMSH2 (-118T>C and IVS12-6T>C) polymorphisms in patients with gastric carcinoma and normal controls, and to evaluate the association between these polymorphisms and the risk of gastric cancer in a hospital-based Chinese population. Genomic DNA was extracted from peripheral blood lymphocytes. A TaqMan assay was used to determine the genotype and allele frequencies of hMLH1 and hMSH2 polymorphisms in data obtained from 554 gastric cancer cases and 592 controls. Unconditional logistic regression was used to assess the association between the four single nucleotide polymorphisms (SNPs) and gastric carcinoma risk. No evidence of an association among any of the four polymorphisms and the risk of gastric cancer was observed. However, when gastric cancer patients were further stratified by age, gender, smoking status, alcohol use and clinicopathological characteristics, and compared with the control populations, the combined variant genotype hMSH2 -118T>C (TC+CC) was not only associated with an increased risk of gastric cancer in subgroups of younger subjects [ages ≤63years; adjusted odds ratio (OR)=1.51, 95% confidence interval (CI), 1.05–2.16], but also with diffuse tumors (adjusted OR=1.41, 95% CI, 1.01–1.96). These data indicate that the polymorphisms of -93G>A, I219V and IVS12-6T>C are not associated with the risk of gastric cancer. However, hMSH2-118T>C combined with variant genotypes (TC+CC) may confer a potential risk of gastric cancer in the Chinese population.
gastric cancer; polymorphism; hMLH1; hMSH2