title: Loss of imprinting of insulin-like growth factor 2 is associated with increased risk of lymph node metastasis and gastric corpus cancer.
abstract: BACKGROUND
  The aim of this study was to determine the clinicopathological features of gastric cancers with loss of imprinting (LOI) of LIT1. Insulin-like growth factor 2 (IGF2) and H19 in Chinese patients.
  
  
  METHODS
  DNA and RNA from tumours were amplified and then digested with RsaI, ApaI and HinfI, and RsaI respectively to determine the LOI status. The demographic and clinicopathological characteristics in LOI positive and LOI negative patients were compared and tested with Statistical analysis.
  
  
  RESULTS
  Of the 89 patients enrolled for analysis, 22, 40 and 35 were heterozygous and thus informative for LIT1, IGF2 and H19 LOI analyses respectively. The positive rate of LIT1, IGF2 and H19 LOI of gastric cancer tissues were 54.6% (12/22), 45% (18/40) and 8.6% (3/32) in Chinese patients. Gastric corpus cancer (8/10, 80%) were more likely to have LOI of IGF2 in tumours than antrum cancers (10/30, 33.3%){odds ratio (OR) = 8, 95% confidence intervals (CI) = 1.425-44.920, p = 0.018)}. LOI of IGF2 in tumours was also associated with the lymph node metastasis (LNM) (OR = 4.5, 95% CI = 1.084-18.689, p = 0.038).
  
  
  CONCLUSIONS
  IGF2 LOI is present in high frequency in Chinese gastric cancer patients, especially those with gastric corpus cancer.
authors.affiliation: Research Center for Medicine, China Medical University the Shengjing Hopital, No 36, Sanhao ST, Heping District, Shenyang 110004, PR China. luyang7408@163.com
authors.forename: Yang
authors.initials: Y
authors.lastname: Lu
authors.forename: Ping
authors.initials: P
authors.lastname: Lu
authors.forename: Zhi
authors.initials: Z
authors.lastname: Zhu
authors.forename: Huimian
authors.initials: H
authors.lastname: Xu
authors.forename: Xike
authors.initials: X
authors.lastname: Zhu
mesh_terms: D000368:Aged; D044466:Asian People; D005260:Female; D020022:Genetic Predisposition to Disease; D018392:Genomic Imprinting; D006801:Humans; D007335:Insulin-Like Growth Factor II / Q000235:genetics*; D019656:Loss of Heterozygosity; D008207:Lymphatic Metastasis / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D024642:Potassium Channels, Voltage-Gated / Q000235:genetics; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated / Q000235:genetics; D012307:Risk Factors; D013274:Stomach Neoplasms / Q000235:genetics* / Q000473:pathology
chemical_list: C094335:H19 long non-coding RNA; C035170:IGF2 protein, human; C485621:KCNQ1OT1 long non-coding RNA, human; D024642:Potassium Channels, Voltage-Gated; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated; D007335:Insulin-Like Growth Factor II