The rs391957 variant cis-regulating oncogene GRP78 expression contributes to the risk of hepatocellular carcinoma

Carcinogenesis. 2013 Jun;34(6):1273-80. doi: 10.1093/carcin/bgt061. Epub 2013 Feb 15.

Abstract

Glucose-regulated protein 78 (GRP78) is one of the most important responders to disease-related stress. We assessed the association of the promoter polymorphisms of GRP78 with risk of hepatocellular carcinoma (HCC) and GRP78 expression in a Chinese population. We examined 1007 patients undergoing diagnostic HCC and 810 unrelated healthy controls. Mechanisms by which the GRP78 promoter polymorphism modulates HCC risk and GRP78 levels were analyzed. The promoter haplotype and diplotype carrying rs391957 (-415bp) allele G and genotype GG was strongly associated with HCC risk. Luciferase reporter assays indicated that the promoter carrying rs391957 allele G (haplotype GCCd) showed increased activity in HepG2 cells and Hela cells. rs391957 was also shown to increase the affinity of the transcriptional activator Ets-2, the resistance to apoptosis, as well as cell instability in stressful microenvironment. Furthermore, compared with allele A, rs391957 allele G was associated with higher levels of GRP78 mRNA and protein in HCC tissues. These findings provided new insights into the pathogenesis of HCC and an unexpected effect of the interaction between rs391957 and Ets-2 on hepatocarcinogenesis, and especially supported the hypothesis that stress-related and evolutionarily conserved genetic variant(s) influencing transcriptional regulation could predict susceptibilities.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis / genetics
  • Base Sequence
  • Binding Sites
  • Biomarkers, Tumor / genetics
  • Carcinoma, Hepatocellular / genetics*
  • Cell Line, Tumor
  • Endoplasmic Reticulum Chaperone BiP
  • Endoplasmic Reticulum Stress / genetics*
  • Genetic Predisposition to Disease
  • Genetic Variation
  • Genotype
  • HeLa Cells
  • Heat-Shock Proteins / genetics*
  • Hep G2 Cells
  • Humans
  • Liver Neoplasms / genetics*
  • Polymorphism, Single Nucleotide
  • Promoter Regions, Genetic / genetics
  • Proto-Oncogene Protein c-ets-2 / genetics
  • Proto-Oncogene Protein c-ets-2 / metabolism*
  • Risk
  • Sequence Analysis, DNA
  • Transcription, Genetic

Substances

  • Biomarkers, Tumor
  • ETS2 protein, human
  • Endoplasmic Reticulum Chaperone BiP
  • HSPA5 protein, human
  • Heat-Shock Proteins
  • Proto-Oncogene Protein c-ets-2