title: [Expression of DNA methyltransferase 1, 3A and 3B mRNA in the epithelial ovarian carcinoma].
abstract: OBJECTIVE
  To explore the role of DNA methyltransferases (DNMT) 1, 3A, 3B in the development of epithelial ovarian carcinoma.
  
  
  METHODS
  Semi-quantitative RT-PCR method was used to detect the mRNA levels of DNMT 1, 3A and 3B in the tissues of epithelial ovarian carcinoma from 55 cancer patients (40 primary and 15 recurrent cancer) and 20 normal ovary tissues, and the relevant clinical pathological parameters were analyzed.
  
  
  RESULTS
  DNMT1 mRNA levels were 1.15, 3.11, 2.85, respectively in normal ovary, primary and recurrent ovarian epithelial cancer tissues, with significant difference between them (P < 0.05). DNMT3A mRNA levels had no obvious changes in the different groups, being 1.32, 0.71, 1.24, respectively (P > 0.05). DNMT3B mRNA levels were 0.25, 0.60, 2.12, in normal ovary, primary and recurrent ovarian epithelial cancer tissues, respectively and there was a significant increase in recurrent cancer tissues compared with normal and primary ovary cancer tissues (P < 0.01). In the primary ovarian cancer tissues, DNMT1 mRNA levels were over expressed in the tissues of low-moderate differentiated (4.92, 1.38), stage III-IV (6.02, 2.13) and lymphatic metastasis (8.25, 2.40; P < 0.05). DNMT 1, 3A, 3B mRNA were over expressed in primary carcinoma, serous carcinoma and clear cell carcinoma of the ovary (5.64, 1.00, 0.78), in comparison with the other pathologic types (1.76, 0.44, 0.23), the differences were significant (P < 0.05). Using COX regression analysis, and after analyzing the parameters effecting survival in epithelial ovarian cancer tissues, including DNMT1, 3A, 3B mRNA level and pathologic type, differentiation, surgical staging, lymphatic metastasis as well as residue tumor post cytoreductive surgery, we found that the mRNA level of DNMT3B was the only factor affecting survival of ovarian cancer patients.
  
  
  CONCLUSIONS
  DNMT1, 3B mRNA were overexpressed in primary and recurrent epithelial ovarian carcinoma, and they have some correlation with clinical pathology and prognosis of epithelial ovarian carcinoma.
authors.affiliation: Department of Obstetrics and Gynecology, Peking University First Hospital, Beijing 100034, China.
authors.forename: Chun-ling
authors.initials: CL
authors.lastname: Chen
authors.forename: Xin
authors.initials: X
authors.lastname: Yan
authors.forename: Yu-nong
authors.initials: YN
authors.lastname: Gao
authors.forename: Qin-ping
authors.initials: QP
authors.lastname: Liao
mesh_terms: D015254:DNA Modification Methylases / Q000096:biosynthesis*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000378:metabolism / Q000473:pathology; D009367:Neoplasm Staging; D010051:Ovarian Neoplasms / Q000378:metabolism* / Q000473:pathology*; D012333:RNA, Messenger / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D012333:RNA, Messenger; D015254:DNA Modification Methylases