Effect of RAGE gene polymorphisms and circulating sRAGE levels on susceptibility to gastric cancer: a case–control study

Taijie Li, Weijuan Qin, Yanqiong Liu, Shan Li, Xue Qin, Zhiming Liu

To investigate the influence of polymorphisms in the receptor for advanced glycation end products (RAGE) gene and circulating soluble RAGE (sRAGE) levels on susceptibility to gastric cancer, and identify whether these polymorphisms were correlated with serum sRAGE levels. We performed a hospital-based case-control study involving 200 gastric cancer patients and 207 cancer-free controls. Four well-characterized RAGE genetic polymorphisms, namely, rs1800624, rs1800625, rs184003, and rs2070600 were genotyped by PCR-RFLP. The rs2070600 AG genotype might play a predominant role in the development of gastric cancer (adjusted OR 1.62, 95% CI 1.03-2.58). In contrast, the rs184003 GT genotype represented significantly reduced risk for gastric cancer (adjusted OR 0.62, 95% CI 0.39-0.99). Subgroup analysis demonstrated that rs2070600 AG variant genotype enhanced the gastric cancer risk among nonsmokers (OR 1.71, 95% CI 1.01-2.91), nondrinkers (OR 1.75, 95% CI 1.03-2.97), and patients with tumor stage III (OR 2.00, 95% CI 1.13-3.56). The average sRAGE levels in the gastric cancer patients were significantly decreased compared with those of the healthy controls. Subjects carrying the rs2070600 AG genotype had a decreased ability to produce sRAGE. Subjects carrying the rs184003 T variant allele had an increased ability to sRAGE. These findings suggested that the variant genotypes of rs184003 and rs2070600 in the RAGE gene exhibit significant associations with gastric cancer risk and circulating sRAGE levels inverse change simultaneously, leading to a marked causal estimate between lowered sRAGE levels and increased gastric cancer risk.