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- Duell, Eric J, et al.
(författare)
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Vitamin C transporter gene (SLC23A1 and SLC23A2) polymorphisms, plasma vitamin C levels, and gastric cancer risk in the EPIC cohort
- 2013
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Ingår i: Genes & Nutrition. - : Springer Berlin/Heidelberg. - 1555-8932 .- 1865-3499. ; 8:6, s. 549-560
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Tidskriftsartikel (refereegranskat)abstract
- Vitamin C is known to protect mucosal tissues from oxidative stress and inhibit nitrosamine formation in the stomach. High consumption of fruits, particularly citrus, and higher circulating vitamin C concentrations may be inversely associated with gastric cancer (GC) risk. We investigated 20 polymorphisms in vitamin C transporter genes SCL23A1 and SCL23A2 and GC risk in 365 cases and 1,284 controls nested within the European Prospective Investigation into Cancer and Nutrition cohort. We also evaluated the association between these polymorphisms and baseline plasma vitamin C levels in a subset of participants. Four SNPs were predictors of plasma vitamin C levels (SLC23A1 rs11950646 and rs33972313; SLC23A2 rs6053005 and rs6133175) in multivariable linear regression models. One SNP (SLC23A2 rs6116569) was associated with GC risk, in particular non-cardia GC (OR = 1.63, 95 % CI = 1.11-2.39, based on 178 non-cardia cases), but this association was attenuated when plasma vitamin C was included in the logistic regression model. Haplotype analysis of SLC23A1 yielded no associations with GC. In SLC23A2, one haplotype was associated with both overall and non-cardia GC, another haplotype was associated with GC overall, and a third was associated with intestinal-type GC. Common variants in SLC23A1 and SLC23A2 may influence plasma vitamin C concentration independent of dietary intake, and variation in SLC23A2 may influence GC risk. Additional prospective studies in large populations and consortia are recommended. Investigation of variation in vitamin C transporter genes may shed light on the preventative properties of vitamin C in gastric carcinogenesis.
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| 2. |
- Espinosa-Parrilla, Yolanda, et al.
(författare)
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Genetic association of gastric cancer with miRNA clusters including the cancer-related genes MIR29, MIR25, MIR93 and MIR106: Results from the EPIC-EURGAST study
- 2014
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Ingår i: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 135:9, s. 2065-2076
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Tidskriftsartikel (refereegranskat)abstract
- MicroRNAs (miRNAs) are post-transcriptional gene regulators involved in a wide range of biological processes including tumorigenesis. Deregulation of miRNA pathways has been associated with cancer but the contribution of their genetic variability to this disorder is poorly known. We analyzed the genetic association of gastric cancer (GC) and its anatomical and histological subtypes, with 133 single-nucleotide polymorphisms (SNPs) tagging 15 isolated miRNAs and 24 miRNA clusters potentially involved in cancer, in 365 GC cases and 1,284 matched controls within the European Prospective Investigation into Cancer and Nutrition cohort. Various SNPs were associated with GC under the log-additive model. Furthermore, several of these miRNAs passed the gene-based permutation test when analyzed according to GC subtypes: three tagSNPs of the miR-29a/miR-29b-1 cluster were associated with diffuse subtype (minimum p-value=1.7 x 10(-4); odds ratio, OR=1.72; 95% confidence interval, CI=1.30-2.28), two tagSNPs of the miR-25/miR-93/miR-106b cluster were associated with cardia GC (minimum p-value=5.38 x 10(-3); OR=0.56, 95% CI=0.37-0.86) and one tagSNP of the miR-363/miR-92a-2/miR-19b-2/miR-20b/miR-18b/miR-106a cluster was associated with noncardia GC (minimum p-value=5.40 x 10(-3); OR=1.41, 95% CI=1.12-1.78). Some functionally validated target genes of these miRNAs are implicated in cancer-related processes such as methylation (DNMT3A, DNMT3B), cell cycle (E2F1, CDKN1A, CDKN1C), apoptosis (BCL2L11, MCL1), angiogenesis (VEGFA) and progression (PIK3R1, MYCN). Furthermore, we identified genetic interactions between variants tagging these miRNAs and variants in their validated target genes. Deregulation of the expression of these miRNAs in GC also supports our findings, altogether suggesting for the fist time that genetic variation in MIR29, MIR25, MIR93 and MIR106b may have a critical role in genetic susceptibility to GC and could contribute to the molecular mechanisms of gastric carcinogenesis.
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