TGFBI promoter hypermethylation correlating with paclitaxel chemoresistance in ovarian cancer

J Exp Clin Cancer Res. 2012 Jan 16;31(1):6. doi: 10.1186/1756-9966-31-6.

Abstract

The purpose of this study is to determine the methylation status of Transforming growth factor-beta-inducible gene-h3 (TGFBI) and its correlation with paclitaxel chemoresistance in ovarian cancer. The methylation status of TGFBI was examined in ovarian cancer and control groups by methylation-specific PCR (MSP) and bisulfite sequencing PCR (BSP). The TGFBI expression and cell viability were compared by Quantitative Real-Time PCR, Western Blotting and MTT assay before and after demethylating agent 5-aza-2'-deoxycytidine (5-aza-dc) treatment in 6 cell lines (SKOV3, SKOV3/TR, SKOV3/DDP, A2780, 2780/TR, OVCAR8). In our results, TGFBI methylation was detected in 29/40 (72.5%) of ovarian cancer and 1/10 (10%) of benign ovarian tumors. No methylation was detected in normal ovarian tissues (P < 0.001). No statistical correlation between RUNX3 methylation and clinicopathological characteristics was observed. A significant correlation between TGFBI methylation and loss of TGFBI mRNA expression was found (P < 0.001). The methylation level of TGFBI was significantly higher in paclitaxel resistant cell lines (SKOV3/TR and 2780/TR) than that in the sensitive pairs (P < 0.001). After 5-aza-dc treatment, the relative expression of TGFBI mRNA and protein increased significantly in SKOV3/TR and A2780/TR cells. However, no statistical differences of relative TGFBI mRNA expression and protein were found in other cells (all P > 0.05), which showed that re-expression of TGFBI could reverse paclitaxel chemoresistance. Our results show that TGFBI is frequently methylated and associated with paclitaxel-resistance in ovarian cancer. TGFBI might be a potential therapeutic target for the enhancement of responses to chemotherapy in ovarian cancer patients.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Carcinoma / drug therapy
  • Carcinoma / genetics*
  • Carcinoma / pathology
  • Cell Line, Tumor
  • DNA Methylation*
  • DNA, Neoplasm / genetics
  • DNA, Neoplasm / metabolism
  • Drug Resistance, Neoplasm / genetics*
  • Epigenesis, Genetic
  • Extracellular Matrix Proteins / genetics*
  • Female
  • Humans
  • Middle Aged
  • Neoplasm Staging
  • Ovarian Neoplasms / drug therapy
  • Ovarian Neoplasms / genetics*
  • Ovarian Neoplasms / pathology
  • Paclitaxel / therapeutic use
  • Promoter Regions, Genetic
  • Transforming Growth Factor beta / genetics*

Substances

  • DNA, Neoplasm
  • Extracellular Matrix Proteins
  • Transforming Growth Factor beta
  • betaIG-H3 protein
  • Paclitaxel