A novel MEK1/2 inhibitor induces G1/S cell cycle arrest in human fibrosarcoma cells

Oncol Rep. 2010 Aug;24(2):329-33. doi: 10.3892/or_00000863.


Blockade of the ERK pathway has antitumor effects against malignant tumor cells. In this study, we investigated the antitumor activity of JTP-70902, a novel specific MEK inhibitor, against human fibrosarcoma cells in which the ERK pathway is constitutively activated. JTP-70902 was synthesized at Japan Tabacco. Human fibrosarcoma HT1080 cells were cultured. JTP-70902 was added at various concentrations. The number of viable cells was counted employing a trypan blue dye exclusion test. Unsynchronized cells were exposed to JTP-70902 for 24 h. The nuclei were stained with propidium iodide. The DNA content was measured using a FACSCalibur flow cytometer. Protein extraction and Western blot analysis were performed. (1) A dose-dependent inhibition of cell growth was observed at concentrations of 10 nM or more. Forty-eight hours after the treatment, the growth of HT1080 cells was completely inhibited by 200 nM JTP-70902. (2) FACS analysis revealed that a 24-h exposure to JTP-70902 increased the population of G1/S phase cells in a dose-dependent manner. (3) The phosphorylation of ERK was inhibited by JTP-70902. Furthermore, after the treatment with JTP-70902, p21WAF1/CIP1 and p27KIP1 protein expression increased and the phosphorylation of RB was reduced. Our results showed that JTP-70902 inhibits cell growth and induces cell cycle arrest in human Ras mutant fibrosarcoma cells. These results indicate that JTP-70902 might be an attractive compound for molecular-targeting chemotherapy for malignant soft tissue tumors with the activation of the Ras-MEK-ERK pathway.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Agents / pharmacology
  • Cell Cycle / drug effects*
  • Cell Cycle / physiology
  • Cell Proliferation / drug effects
  • Cyclin-Dependent Kinase Inhibitor p21 / metabolism
  • Cyclin-Dependent Kinase Inhibitor p27 / metabolism
  • Drug Evaluation, Preclinical
  • Fibrosarcoma / pathology*
  • G1 Phase / drug effects
  • Humans
  • MAP Kinase Kinase 1 / antagonists & inhibitors*
  • MAP Kinase Kinase 2 / antagonists & inhibitors*
  • Protein Kinase Inhibitors / pharmacology*
  • Pyrimidinones / pharmacology
  • S Phase / drug effects
  • Sulfonamides / pharmacology
  • Time Factors
  • Tumor Cells, Cultured


  • Antineoplastic Agents
  • CDKN1A protein, human
  • Cyclin-Dependent Kinase Inhibitor p21
  • Protein Kinase Inhibitors
  • Pyrimidinones
  • Sulfonamides
  • Cyclin-Dependent Kinase Inhibitor p27
  • MAP2K2 protein, human
  • MAP Kinase Kinase 1
  • MAP Kinase Kinase 2
  • MAP2K1 protein, human
  • N-(3-(5-(4-bromo-2-fluorophenylamino)-3-cyclopropyl-8-methyl-2,4,7-trioxo-3,4,7,8-tetrahydro-2H-pyrido(2,3-d)pyrimidin-1-yl)phenyl)methanesulfonamide