Expression profiling identifies altered expression of genes that contribute to the inhibition of transforming growth factor-beta signaling in ovarian cancer

Cancer Res. 2006 Sep 1;66(17):8404-12. doi: 10.1158/0008-5472.CAN-06-0683.


Ovarian cancer is resistant to the antiproliferative effects of transforming growth factor-beta (TGF-beta); however, the mechanism of this resistance remains unclear. We used oligonucleotide arrays to profile 37 undissected, 68 microdissected advanced-stage, and 14 microdissected early-stage papillary serous cancers to identify signaling pathways involved in ovarian cancer. A total of seven genes involved in TGF-beta signaling were identified that had altered expression >1.5-fold (P < 0.001) in the ovarian cancer specimens compared with normal ovarian surface epithelium. The expression of these genes was coordinately altered: genes that inhibit TGF-beta signaling (DACH1, BMP7, and EVI1) were up-regulated in advanced-stage ovarian cancers and, conversely, genes that enhance TGF-beta signaling (PCAF, TFE3, TGFBRII, and SMAD4) were down-regulated compared with the normal samples. The microarray data for DACH1 and EVI1 were validated using quantitative real-time PCR on 22 microdissected ovarian cancer specimens. The EVI1 gene locus was amplified in 43% of the tumors, and there was a significant correlation (P = 0.029) between gene copy number and EVI1 gene expression. No amplification at the DACH1 locus was found in any of the samples. DACH1 and EVI1 inhibited TGF-beta signaling in immortalized normal ovarian epithelial cells, and a dominant-negative DACH1, DACH1-Delta DS, partially restored signaling in an ovarian cancer cell line resistant to TGF-beta. These results suggest that altered expression of these genes is responsible for disrupted TGF-beta signaling in ovarian cancer and they may be useful as new and novel therapeutic targets for ovarian cancer.

Publication types

  • Research Support, N.I.H., Intramural

MeSH terms

  • Female
  • Gene Expression Profiling*
  • Genes, Reporter
  • Humans
  • Neoplasm Staging
  • Neoplasms, Cystic, Mucinous, and Serous / genetics
  • Neoplasms, Cystic, Mucinous, and Serous / pathology
  • Oligonucleotide Array Sequence Analysis
  • Ovarian Neoplasms / genetics*
  • Ovarian Neoplasms / pathology
  • Polymerase Chain Reaction
  • RNA, Neoplasm / genetics
  • RNA, Neoplasm / isolation & purification
  • Signal Transduction
  • Transforming Growth Factor beta / physiology*


  • RNA, Neoplasm
  • Transforming Growth Factor beta