title: Methylation of CDX2 as a Predictor in Poor Clinical Outcome of Patients with Colorectal Cancer.
abstract: OBJECTIVE
  Increased DNA methylation within the promoter regions of tumor suppressor genes has been associated with gene silencing in various cancers. CDX2, a caudal-related homeobox transcription factor, represents a key tumor suppressor in colorectal cancer. However, the pathological role of its promoter methylation has not yet been well defined in colorectal cancer.
  
  
  METHODS
  We measured CDX2 promoter methylation by methylation-specific PCR (MSP) and CDX2 mRNA levels by real-time quantitative reverse transcription-PCR in both tumor and normal control tissues collected from 108 colorectal cancer patients and then performed correlation analyses. We also determined whether CDX2 promoter methylation status was associated with any clinicopathological features and prognosis in these patients.
  
  
  RESULTS
  CDX2 was expressed in all normal mucosa, but only in 38 (35.2%) tumor tissues. CDX2 promoter methylation was detected in 43 (39.8%) tumor samples, but in none of the normal tissue specimens. DNA methylation correlated with decreased mRNA level in these tumors (p < 0.05). The methylation of the CDX2 promoter was associated with enhanced lymph node metastases and shorter survival time (p = 0.0273), but was independent of tumor stage, tumor differentiation, gender, and age.
  
  
  CONCLUSIONS
  Enhanced CDX2 promoter methylation is associated with gene silencing in a subgroup of colorectal cancer patients with lymph node metastasis and shorter survival times.
authors.affiliation: 1 Department of Pathology, The First Affiliated Hospital of Zhengzhou University , Zhengzhou, China .
authors.forename: Guozhong
authors.initials: G
authors.lastname: Jiang
authors.affiliation: 2 Department of Oncology, The Zhengzhou Central Hospital Affiliated to Zhengzhou University , Zhengzhou, China .
authors.forename: Chenglin
authors.initials: C
authors.lastname: Luo
authors.affiliation: 3 Department of Pathology, Henan Tumor Hospital , Zhengzhou, China .
authors.forename: Miaomiao
authors.initials: M
authors.lastname: Sun
authors.affiliation: 1 Department of Pathology, The First Affiliated Hospital of Zhengzhou University , Zhengzhou, China .
authors.forename: Zhihua
authors.initials: Z
authors.lastname: Zhao
authors.affiliation: 1 Department of Pathology, The First Affiliated Hospital of Zhengzhou University , Zhengzhou, China .
authors.forename: Wencai
authors.initials: W
authors.lastname: Li
authors.affiliation: 1 Department of Pathology, The First Affiliated Hospital of Zhengzhou University , Zhengzhou, China .
authors.forename: Kuisheng
authors.initials: K
authors.lastname: Chen
authors.affiliation: 4 School of Basic Medicine, Zhengzhou University , Zhengzhou, China .
authors.forename: Tianli
authors.initials: T
authors.lastname: Fan
mesh_terms: D000328:Adult; D000071616:CDX2 Transcription Factor / Q000235:genetics* / Q000378:metabolism; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000378:metabolism; D019175:DNA Methylation; D005260:Female; D016147:Genes, Tumor Suppressor; D005820:Genetic Testing; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011401:Promoter Regions, Genetic; D016896:Treatment Outcome
chemical_list: D000071616:CDX2 Transcription Factor; C491270:CDX2 protein, human
keywords: CDX2; colorectal cancer; methylation