Haijuan Gu

Aberrant microRNA (miRNA) expression is presently proposed to correlate with various human cancers and common single-nucleotide polymorphisms (SNP) at miRNA genes can influence the maturation of miRNAs or miRNA-mediated transcriptional regulation. However, whether miRNAs SNP alter gastric cancer susceptibility is still unclear. Here we investigated the possible role of a common A/G polymorphism (rs895819) within hsa-mir-27a in the development or progression of gastric cancer, and assessed the effect of rs895819 on the expression of miR-27a and its target gene Zinc finger and BTB domain containing 10 (ZBTB10). In the present case-control study, we found that subjects with the variant genotypes (AG + GG) showed a significantly increased risk of gastric cancer relative to AA carriers (adjusted odds ratio = 1.48, 95% confidence interval 1.06-2.05; P = 0.019). The elevated risk was especially evident in older subjects (age >58 years), men, nonsmokers and rural subjects. A significant association of hsa-mir-27a variant genotypes with lymph node metastasis was also observed. Further functional analyses indicated that variant genotypes might be responsible for elevated miR-27a levels and reduced ZBTB10 mRNA. Moreover, an inverse correlation was found between ZBTB10 and miR-27a levels. In conclusion, we were the first to show that a common polymorphism (rs895819) in hsa-mir-27a, by modulating miR-27a and ZBTB10 levels, acted as an important factor of the gastric cancer susceptibility.

PURPOSE: It has been shown that the expression of the receptor for advanced glycation end products (RAGE) is closely associated with invasion and metastasis in gastric cancer. A Gly82Ser polymorphism in exon 3 of RAGE gene was identified and thought to have an effect on the functions of its protein. Therefore, the goal of the present study was to investigate whether the polymorphism is involved in the development or progression of gastric cancer. EXPERIMENTAL DESIGN: In the hospital-based case-control study, the RAGE genotypes were determined using PCR-RFLP in 566 individuals (283 gastric cancer patients and 283 age- and sex-matched controls). RESULTS: The distribution of genotype was significantly different between cases and controls (P = 0.038). Compared with the wild-type 82Gly/Gly carriers, subjects with the variant genotypes (82Gly/Ser and 82Ser/Ser) had a significantly higher risk of gastric cancer (adjusted odds ratio, 1.47; 95% confidence interval, 1.05-2.06). Moreover, the elevated gastric cancer risk was especially evident in younger individuals (ages < or =58 years), nonsmokers, and rural subjects. Further analyses revealed that the variant genotypes were associated with adjacent organ invasion in the subanalysis of gastric cancer patients. CONCLUSIONS: Our findings indicate that the RAGE Gly82Ser polymorphism may confer not only an increased risk of gastric cancer but also with invasion of gastric cancer in the Chinese population.