Expression of drug targets in patients treated with sorafenib, carboplatin and paclitaxel

PLoS One. 2013 Aug 6;8(8):e69748. doi: 10.1371/journal.pone.0069748. Print 2013.

Abstract

Introduction: Sorafenib, a multitarget kinase inhibitor, targets members of the mitogen-activated protein kinase (MAPK) pathway and VEGFR kinases. Here we assessed the association between expression of sorafenib targets and biomarkers of taxane sensitivity and response to therapy in pre-treatment tumors from patients enrolled in ECOG 2603, a phase III comparing sorafenib, carboplatin and paclitaxel (SCP) to carboplatin, paclitaxel and placebo (CP).

Methods: Using a method of automated quantitative analysis (AQUA) of in situ protein expression, we quantified expression of VEGF-R2, VEGF-R1, VEGF-R3, FGF-R1, PDGF-Rβ, c-Kit, B-Raf, C-Raf, MEK1, ERK1/2, STMN1, MAP2, EB1 and Bcl-2 in pretreatment specimens from 263 patients.

Results: An association was found between high FGF-R1 and VEGF-R1 and increased progression-free survival (PFS) and overall survival (OS) in our combined cohort (SCP and CP arms). Expression of FGF-R1 and VEGF-R1 was higher in patients who responded to therapy ((CR+PR) vs. (SD+PD+ un-evaluable)).

Conclusions: In light of the absence of treatment effect associated with sorafenib, the association found between FGF-R1 and VEGF-R1 expression and OS, PFS and response might reflect a predictive biomarker signature for carboplatin/paclitaxel-based therapy. Seeing that carboplatin and pacitaxel are now widely used for this disease, corroboration in another cohort might enable us to improve the therapeutic ratio of this regimen.

Publication types

  • Clinical Trial, Phase III
  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural

MeSH terms

  • Antineoplastic Agents / pharmacology
  • Antineoplastic Agents / therapeutic use*
  • Biomarkers, Tumor / metabolism
  • Carboplatin / pharmacology
  • Carboplatin / therapeutic use
  • Female
  • Gene Expression Regulation, Neoplastic / drug effects*
  • Humans
  • Kaplan-Meier Estimate
  • Male
  • Middle Aged
  • Molecular Targeted Therapy*
  • Niacinamide / analogs & derivatives
  • Niacinamide / pharmacology
  • Niacinamide / therapeutic use
  • Paclitaxel / pharmacology
  • Paclitaxel / therapeutic use
  • Phenylurea Compounds / pharmacology
  • Phenylurea Compounds / therapeutic use
  • Sorafenib

Substances

  • Antineoplastic Agents
  • Biomarkers, Tumor
  • Phenylurea Compounds
  • Niacinamide
  • Sorafenib
  • Carboplatin
  • Paclitaxel