title: CDH1 methylation in preoperative peritoneal washes is an independent prognostic factor for gastric cancer.
abstract: OBJECTIVE
  To investigate the clinical value of CDH1 methylation in preoperative peritoneal washes (PPW) from gastric cancer patients.
  
  
  METHODS
  CDH1 methylation was detected by real-time methylation specific-PCR in tumor tissues and corresponding PPW from 92 gastric cancer patients, gastric mucosa from 40 chronic gastritis patients and 48 normal persons.
  
  
  RESULTS
  CDH1 methylation was found in 75 of 92 (81.5%) gastric cancer tissues, which significantly correlated with size, growth pattern, differentiation, lymphatic invasion, venous invasion, invasion depth, lymph node metastasis, distant metastasis, and TNM stage of tumor (all P < 0.05), but its relationship to age, gender, tumor site, and H. pylori infection was not found (all P > 0.05). The percentage of CDH1 methylation in PPW was 48.9%, of which the Aζ value of ROC curve was 0.8 compared to that in gastric cancer tissues. Kaplan-Meier analysis showed that there was a significant difference in disease-free survival (DFS) between the patients with or without methylated CDH1 in their PPW (χ(2) = 109.64, P < 0.000). Cox regression analysis revealed CDH1 methylation in PPW was an independent risk factor for gastric cancer patients, with a remarkable decrease in DFS after postoperative 30 months.
  
  
  CONCLUSIONS
  Methylated CDH1 in PPW predicts poor prognosis for gastric cancer patients.
authors.affiliation: Zhejiang Cancer Research Institute, Zhejiang Province Cancer Hospital, Zhejiang Cancer Center, Banshanqiao District, Hangzhou, China.
authors.forename: Qi-Ming
authors.initials: QM
authors.lastname: Yu
authors.forename: Xin-Bao
authors.initials: XB
authors.lastname: Wang
authors.forename: Jun
authors.initials: J
authors.lastname: Luo
authors.forename: Shi
authors.initials: S
authors.lastname: Wang
authors.forename: Xian-Hua
authors.initials: XH
authors.lastname: Fang
authors.forename: Jiang-Liu
authors.initials: JL
authors.lastname: Yu
authors.forename: Zhi-Qiang
authors.initials: ZQ
authors.lastname: Ling
mesh_terms: D000328:Adult; D000368:Aged; D015703:Antigens, CD; D015820:Cadherins / Q000235:genetics*; D018899:CpG Islands; D019175:DNA Methylation; D005260:Female; D005753:Gastric Mucosa / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D010537:Peritoneum / Q000378:metabolism*; D011379:Prognosis; D011401:Promoter Regions, Genetic; D013274:Stomach Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology
chemical_list: D015703:Antigens, CD; C513384:CDH1 protein, human; D015820:Cadherins