Frequent promoter hypermethylation of TGFBI in epithelial ovarian cancer

Gynecol Oncol. 2010 Jul;118(1):58-63. doi: 10.1016/j.ygyno.2010.03.025. Epub 2010 Apr 24.


Objectives: Using pharmacologic unmasking and genome-wide differential methylation analysis, we identified a novel methylated gene in ovarian cancers.

Methods: Two ovarian cancer cells (OVCAR-3, ES-2) that showed synergistic growth inhibition by 5-aza-dC and cisplatin were selected. After treatment with 5-aza-dC, differential expression profiles were compared using microarray that contained 38,500 genes. Reactivation of candidate genes and their promoter methylation were validated by real-time RT-PCR, MS-PCR and bisulfite sequencing. Methylation status was tested by MS-PCR in 56 patients with epithelial ovarian cancer and compared to the 38 normal ovarian tissues.

Results: We identified 103 candidate genes that were reactivated by 5-aza-dC treatment. Among those, SFN and TGFBI were commonly reactivated in both cells. Since SFN is a well known methylated marker, we selected TGFBI for further validation. Bisulfite sequencing revealed complete promoter methylation in ES-2 and partial methylation in OVCAR-3. In addition, silencing of TGFBI at the transcription level was reversed by 5-aza-dC treatment. TGFBI methylation was observed in 23 out of 38 (60.5%) cases of ovarian cancer, in no normal ovarian tissues (0 of 38, P=0.001), and in 5 out of 18 (27.8%) borderline tumors (P=0.044). In our cohort, we did not observe any association between methylation of TGFBI and clinicopathologic variables or clinical outcomes.

Conclusion: Our results confirm that TGFBI is frequently methylated in ovarian cancer. Its methylation can be used as a novel epigenetic biomarker in discriminating ovarian cancer from non-cancer or borderline tumors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenocarcinoma / genetics
  • Adenocarcinoma / pathology
  • Adenocarcinoma, Clear Cell / genetics
  • Adenocarcinoma, Clear Cell / pathology
  • Adult
  • Aged
  • Cell Line, Tumor
  • DNA Methylation*
  • Epithelial Cells / pathology
  • Extracellular Matrix Proteins / genetics*
  • Female
  • Humans
  • Middle Aged
  • Oligonucleotide Array Sequence Analysis
  • Ovarian Neoplasms / genetics*
  • Ovarian Neoplasms / pathology
  • Promoter Regions, Genetic
  • Reverse Transcriptase Polymerase Chain Reaction
  • Transforming Growth Factor beta / genetics*


  • Extracellular Matrix Proteins
  • Transforming Growth Factor beta
  • betaIG-H3 protein