title: [Expression and significance of DNMT1 in human keloid fibroblast].
abstract: OBJECTIVE
  To investigate the expression and significance of DNA methyltransferase 1 (DNMT1) in different parts and formation time of keloid fibroblasts.
  
  
  METHODS
  Specimen were collected from fifty-three patients with keloid. The keloids were grouped according to formation time. Immunohistochemistry was used to assay the expression of DNMT1 in normal skin, invasive part, proliferative part and aged part. RT-PCR was adopted to assay the expression of DNMT1 mRNA in each group.
  
  
  RESULTS
  DNMT1 is mainly distributed in the nucleus of fibroblasts. The expression of DNMT1 protein and DNMTl mRNA in keloid (72%) is higher than that in normal skin fibroblasts (8%) (P = 0.001). The expression rate of DNMT1 protein and DNMT1 mRNA in shorter formation time group (100%, Score:10.47 +/- 1.85) is higher than a longer formation time group (45%,Score: 7.71 +/- 1.80) (P = 0.007). The expression rate of DNMT1 protein and DNMT1 mRNA in the invasive part of keloid (100%, Score: 10.47 +/- 1.85) is higher than the proliferative part (78%, Score: 6.63 +/- 1.75) and aged part (38%, Score: 5.53 +/- 1.55) (P = 0.001).
  
  
  CONCLUSIONS
  DNMT1 plays an important role in keloid. The expression of DNMT1 tends to decrease along with the increase of the formation time in keloid. It is also related to the part of keloid. DNMT1 plays an important role in the process of keloid growth and is closely related to infiltrative growth in keloid.
authors.affiliation: Department of Plastic and Burning Surgery, the First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China.
authors.forename: E
authors.initials: E
authors.lastname: Yang
authors.forename: Qi-Pa
authors.initials: QP
authors.lastname: Zou
authors.forename: Heng-Shu
authors.initials: HS
authors.lastname: Zhang
mesh_terms: D000293:Adolescent; D000328:Adult; D002478:Cells, Cultured; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000235:genetics / Q000378:metabolism*; D005260:Female; D005347:Fibroblasts / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007627:Keloid / Q000378:metabolism* / Q000473:pathology; D008297:Male; D012333:RNA, Messenger / Q000235:genetics; D055815:Young Adult
chemical_list: D012333:RNA, Messenger; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases; C000619380:DNMT1 protein, human