MEK1 is associated with carboplatin resistance and is a prognostic biomarker in epithelial ovarian cancer

BMC Cancer. 2014 Nov 18;14:837. doi: 10.1186/1471-2407-14-837.

Abstract

Background: Primary systemic treatment for ovarian cancer is surgery, followed by platinum based chemotherapy. Platinum resistant cancers progress/recur in approximately 25% of cases within six months. We aimed to identify clinically useful biomarkers of platinum resistance.

Methods: A database of ovarian cancer transcriptomic datasets including treatment and response information was set up by mining the GEO and TCGA repositories. Receiver operator characteristics (ROC) analysis was performed in R for each gene and these were then ranked using their achieved area under the curve (AUC) values. The most significant candidates were selected and in vitro functionally evaluated in four epithelial ovarian cancer cell lines (SKOV-3-, CAOV-3, ES-2 and OVCAR-3), using gene silencing combined with drug treatment in viability and apoptosis assays. We collected 94 tumor samples and the strongest candidate was validated by IHC and qRT-PCR in these.

Results: All together 1,452 eligible patients were identified. Based on the ROC analysis the eight most significant genes were JRK, CNOT8, RTF1, CCT3, NFAT2CIP, MEK1, FUBP1 and CSDE1. Silencing of MEK1, CSDE1, CNOT8 and RTF1, and pharmacological inhibition of MEK1 caused significant sensitization in the cell lines. Of the eight genes, JRK (p = 3.2E-05), MEK1 (p = 0.0078), FUBP1 (p = 0.014) and CNOT8 (p = 0.00022) also correlated to progression free survival. The correlation between the best biomarker candidate MEK1 and survival was validated in two independent cohorts by qRT-PCR (n = 34, HR = 5.8, p = 0.003) and IHC (n = 59, HR = 4.3, p = 0.033).

Conclusion: We identified MEK1 as a promising prognostic biomarker candidate correlated to response to platinum based chemotherapy in ovarian cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Agents / pharmacology*
  • Antineoplastic Agents / therapeutic use
  • Apoptosis / genetics
  • Biomarkers
  • Carboplatin / pharmacology*
  • Carboplatin / therapeutic use
  • Carcinoma, Ovarian Epithelial
  • Cell Line, Tumor
  • Cell Survival / drug effects
  • Cell Survival / genetics
  • Cohort Studies
  • Computational Biology
  • Databases, Nucleic Acid
  • Datasets as Topic
  • Drug Resistance, Neoplasm / genetics*
  • Female
  • Gene Silencing
  • Humans
  • MAP Kinase Kinase 1 / antagonists & inhibitors
  • MAP Kinase Kinase 1 / genetics*
  • Neoplasms, Glandular and Epithelial / drug therapy
  • Neoplasms, Glandular and Epithelial / genetics*
  • Neoplasms, Glandular and Epithelial / mortality
  • Ovarian Neoplasms / drug therapy
  • Ovarian Neoplasms / genetics*
  • Ovarian Neoplasms / mortality
  • Prognosis
  • Protein Kinase Inhibitors / pharmacology
  • RNA, Small Interfering / genetics

Substances

  • Antineoplastic Agents
  • Biomarkers
  • Protein Kinase Inhibitors
  • RNA, Small Interfering
  • Carboplatin
  • MAP Kinase Kinase 1
  • MAP2K1 protein, human