Genome-wide association studies (GWAS) of gastric cancer have reported differences in single-nucleotide polymorphism associations for tumor subtypes, particularly when divided by location into the gastric cardia versus the non-cardia.
Dr Christian Abnet and colleagues from Maryland, USA present results for a GWAS using 2350 East Asian gastric cancer cases divided as 1189 gastric cardia and 1027 gastric non-cardia cases and 2708 controls.
The researchers included up to 3042 cardia cases, 4359 non-cardia cases and 7548 controls for replication from 2 Chinese studies and 1 Korean study.
|The team confirmed a previously reported association for rs4072037 in MUC1 for total gastric cancer |
From the GWAS, the team selected 12 top single-nucleotide polymorphisms for each gastric cancer subtype, 4 top single-nucleotide polymorphisms for total gastric cancer, and 1 single-nucleotide polymorphism in MUC1 for replication testing.
The research team observed genome-wide significant associations for rs10074991 in PRKAA1 at 5p13.1 for cardia and non-cardia cancers with per allele odds ratio for the combined endpoint of 0.80.
The researchers observed that at 6p21.1, rs2294693 near UNC5CL was significantly associated with gastric non-cardia cancer risk, with odds ratio of 1.18, but there was only a nominal association for cardia cancer.
The team also confirmed a previously reported association for rs4072037 in MUC1 for total gastric cancer and similar estimates for cardia and non-cardia cancers.
The team found that 3 single-nucleotide polymorphisms in PSCA previously reported to be associated with gastric non-cardia cancer showed no apparent association for cardia cancer.
Dr Abnet's team comments, "Our results suggest that associations for single-nucleotide polymorphisms with gastric cancer show some different results by tumor location in the stomach."