title: The quantification of HER2 and MYC gene fragments in cell-free plasma as putative biomarkers for gastric cancer diagnosis.
abstract: BACKGROUND
  This study aimed to investigate the significance of circulating HER2 and MYC gene fragments quantification in the diagnosis of gastric cancer.
  
  
  METHODS
  Levels of HER2 and MYC genes were evaluated by fluorescence in situ hybridization and real-time PCR in 81 gastric cancer tissues, and by real-time PCR in 36 gastritis tissues. Real-time PCR for HER2 and MYC products was also performed on 184 plasma samples from 81 gastric cancers, eight gastric adenomas, 63 gastritis patients, and 32 healthy individuals.
  
  
  RESULTS
  HER2/HBB and MYC/HBB ratios in tissue and cell-free plasma from gastric cancer patients were significantly higher than those of gastritis tissue and cancer-free individuals. An optimized cut-off value of plasma target gene to HBB ratio, used to differentiate cancer patients from cancer-free individuals, was evaluated using receiver operating characteristic (ROC) curves. Values of 2.0 were calculated for HER2 [area under the ROC curve (AUC), 0.760] and 2.725 for MYC (AUC, 0.767). A combination model of HER2 and MYC provided a better differentiation condition than that for HER2 or MYC only (AUC, 0.850). HER2/HBB ratios in plasma from gastric cancer patients correlated with MYC/HBB ratios.
  
  
  CONCLUSIONS
  Our findings suggest that the measurement of plasma HER2 and MYC gene levels could improve the screening of gastric cancer.
authors.forename: Kyoung Un
authors.initials: KU
authors.lastname: Park
authors.forename: Hee Eun
authors.initials: HE
authors.lastname: Lee
authors.forename: Soo Kyung
authors.initials: SK
authors.lastname: Nam
authors.forename: Kyung Han
authors.initials: KH
authors.lastname: Nam
authors.forename: Do Joong
authors.initials: DJ
authors.lastname: Park
authors.forename: Hyung-Ho
authors.initials: HH
authors.lastname: Kim
authors.forename: Woo Ho
authors.initials: WH
authors.lastname: Kim
authors.forename: Hye Seung
authors.initials: HS
authors.lastname: Lee
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood / Q000235:genetics*; D005260:Female; D016259:Genes, myc / Q000235:genetics*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000097:blood / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013274:Stomach Neoplasms / Q000097:blood / Q000175:diagnosis* / Q000235:genetics*
chemical_list: D014408:Biomarkers, Tumor; D018719:Erb-b2 Receptor Tyrosine Kinases; C508053:ERBB2 protein, human