title: PGC TagSNP and its interaction with H. pylori and relation with gene expression in susceptibility to gastric carcinogenesis.
abstract: BACKGROUND
  Pepsinogen C (PGC) plays an important role in sustaining the cellular differentiation during the process of gastric carcinogenesis. This study aimed to assess the role of PGC tagSNPs and their interactions with Helicobacter pylori (H. pylori) in the development of gastric cancer and its precursor, atrophic gastritis.
  
  
  METHODS
  Four PGC tagSNPs (rs6941539, rs6912200, rs3789210 and rs6939861) were genotyped by Sequenom MassARRAY platform in a total of 2311 subjects consisting of 642 gastric cancer, 774 atrophic gastritis, and 895 healthy control subjects. The mRNA and protein expression levels of PGC in gastric tissues and in serum were respectively measured by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR), immunohistochemistry, and Eenzyme-linked immunoabsorbent assay (ELISA).
  
  
  RESULTS
  We found associations between PGC rs3789210 CG/GG genotypes and reduced gastric cancer risk and between PGC rs6939861 A variant allele and increased risks of both gastric cancer and atrophic gastritis. As for the haplotypes of PGC rs6941539-rs6912200-rs3789210-rs6939861 loci, the TTCA and TTGG haplotypes were respectively associated with increased and reduced risks of both gastric cancer and atrophic gastritis; additionally, the CTCA haplotype was associated with increased atrophic gastritis risk. Very interestingly, rs6912200 CT/TT genotypes had a positive interaction with H. pylori, synergistically elevating the gastric cancer risk. Moreover, healthy subjects who carried rs6912200 CT, TT and CT/TT variant genotypes had lower histological and serum expression levels of PGC protein.
  
  
  CONCLUSIONS
  Our findings highlight an important role of PGC rs3789210 and rs6939861 in altering susceptibility to atrophic gastritis and/or gastric cancer. Moreover, people who carry rs6912200 variant genotypes exhibit higher gastric cancer risk in case of getting H. pylori infection, which strongly suggest a necessity of preventing and/or eliminating H. pylori infection in those individuals.
authors.affiliation: Tumor Etiology and Screening Department of Cancer Institute and General Surgery, the First Affiliated Hospital of China Medical University, and Key Laboratory of Cancer Etiology and Prevention (China Medical University), Liaoning Provincial Education Department, Shenyang, China; Department of Molecular Diagnostics of Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Guangzhou, China.
authors.forename: Cai-Yun
authors.initials: CY
authors.lastname: He
authors.affiliation: Tumor Etiology and Screening Department of Cancer Institute and General Surgery, the First Affiliated Hospital of China Medical University, and Key Laboratory of Cancer Etiology and Prevention (China Medical University), Liaoning Provincial Education Department, Shenyang, China.
authors.forename: Li-Ping
authors.initials: LP
authors.lastname: Sun
authors.affiliation: Tumor Etiology and Screening Department of Cancer Institute and General Surgery, the First Affiliated Hospital of China Medical University, and Key Laboratory of Cancer Etiology and Prevention (China Medical University), Liaoning Provincial Education Department, Shenyang, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Xu
authors.affiliation: Tumor Etiology and Screening Department of Cancer Institute and General Surgery, the First Affiliated Hospital of China Medical University, and Key Laboratory of Cancer Etiology and Prevention (China Medical University), Liaoning Provincial Education Department, Shenyang, China.
authors.forename: Jing-Wei
authors.initials: JW
authors.lastname: Liu
authors.affiliation: Tumor Etiology and Screening Department of Cancer Institute and General Surgery, the First Affiliated Hospital of China Medical University, and Key Laboratory of Cancer Etiology and Prevention (China Medical University), Liaoning Provincial Education Department, Shenyang, China.
authors.forename: Jing-Yi
authors.initials: JY
authors.lastname: Jiang
authors.affiliation: Tumor Etiology and Screening Department of Cancer Institute and General Surgery, the First Affiliated Hospital of China Medical University, and Key Laboratory of Cancer Etiology and Prevention (China Medical University), Liaoning Provincial Education Department, Shenyang, China.
authors.forename: Nan-Nan
authors.initials: NN
authors.lastname: Dong
authors.affiliation: Tumor Etiology and Screening Department of Cancer Institute and General Surgery, the First Affiliated Hospital of China Medical University, and Key Laboratory of Cancer Etiology and Prevention (China Medical University), Liaoning Provincial Education Department, Shenyang, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Yuan
mesh_terms: D002471:Cell Transformation, Neoplastic / Q000235:genetics; D005753:Gastric Mucosa / Q000378:metabolism; D005757:Gastritis, Atrophic / Q000235:genetics*; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D005838:Genotype; D016481:Helicobacter Infections / Q000382:microbiology / Q000473:pathology*; D016480:Helicobacter pylori / Q000302:isolation & purification / Q000472:pathogenicity*; D006801:Humans; D020115:Pepsinogen C / Q000097:blood / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D012333:RNA, Messenger / Q000096:biosynthesis; D013270:Stomach / Q000382:microbiology / Q000473:pathology; D013274:Stomach Neoplasms / Q000097:blood / Q000235:genetics*
chemical_list: D012333:RNA, Messenger; D020115:Pepsinogen C