title: [Methylation status of p16 gene in colorectal carcinoma and normal colonic mucosa].
abstract: OBJECTIVE
  To investigate the methylation status and its significance of 5' CpG island of p16 gene in colorectal carcinoma and normal colonic mucosa.
  
  
  METHODS
  PCR-based methylation assay was applied to examine a total of 60 samples of colorectal carcinoma and paired 60 samples of the normal colonic mucosa for p16 gene methylation in Hpa II, Sac II, Sma I sites.
  
  
  RESULTS
  Methylation was identified in 5' CpG island of p16 gene in both colorectal carcinoma and normal colonic mucosa, but no significant difference obtained between normal mucosa and carcinoma. The methylation status in 5' CpG island of p16 gene in colorectal carcinoma was not related to the tumor size, type, and metastases of the lymph nodes. Nevertheless, there was a significant difference between the methylation status of Hpa II, Sac II and Sma I sites.
  
  
  CONCLUSIONS
  The methylation in 5' CpG island of p16 gene in colonic mucosa is different in various restriction enzyme sites, and the methylation process of p16 gene in both normal colonic mucosa and colorectal carcinomas is complicated. Anyhow, there is a tendency that the increase of methylation in p16 gene is age dependent.
authors.affiliation: Department of Pathology, Medical College, Zhejiang University, HangZhou 310009, China.
authors.forename: J
authors.initials: J
authors.lastname: Zhang
authors.forename: M
authors.initials: M
authors.lastname: Lai
authors.forename: J
authors.initials: J
authors.lastname: Chen
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics / Q000556:secondary; D002288:Adenocarcinoma, Mucinous / Q000235:genetics / Q000556:secondary; D000328:Adult; D000367:Age Factors; D000368:Aged; D003106:Colon / Q000473:pathology; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology; D018899:CpG Islands; D019175:DNA Methylation; D005260:Female; D019942:Genes, p16; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged