Preclinical evaluation of the AKT inhibitor MK-2206 in nasopharyngeal carcinoma cell lines

Invest New Drugs. 2013 Jun;31(3):567-75. doi: 10.1007/s10637-012-9896-5. Epub 2012 Nov 11.

Abstract

Nasopharyngeal carcinoma (NPC) is endemic to Asia and over 40 % of NPC tissues harbor PIK3CA amplifications. This study characterized the preclinical activity of MK-2206, an oral allosteric inhibitor of AKT in 6 NPC cell lines: C666-1, HK1, HONE-1-EBV, HONE-1, CNE-2 and HNE-1. Exposure to increasing concentrations of MK-2206 resulted in over 95 % of growth inhibition in all NPC cell lines with IC50 values in the low micromolar range. Further experiments were performed in 3 representative NPC cell lines: CNE-2 (harbor PIK3CA mutation and most sensitive to MK-2206), C666-1 (carries PIK3CA amplification), and HONE-1-EBV (least sensitive to MK-2206). MK-2206 induced G0/G1 cycle arrest in all 3 cell lines, but could induce apoptosis only in CNE-2 cells. MK-2206 significantly abrogated AKT signaling in all 3 cell lines by inhibiting the activation of AKT and its downstream effectors (FKHR, GSK3β and BAD). MK-2206 also reduced mTOR signaling by reducing activation of mTOR and its downstream 4E-BP1 and p70S6 kinase. MAPK activation was observed in HONE-1 and C666-1 cells, but not in CNE-2 cells following exposure to MK-2206. The addition of MK-2206 to cisplatin (but not with paclitaxel) has a supra-additive inhibitory effect on growth in vitro. In summary, MK-2206 can inhibit growth and abrogate AKT and mTOR signaling in NPC cell lines. This agent is currently being evaluated in a phase II study in metastatic NPC.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Agents / administration & dosage*
  • Carcinoma
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Cisplatin / administration & dosage
  • Heterocyclic Compounds, 3-Ring / administration & dosage*
  • Humans
  • Mitogen-Activated Protein Kinases / metabolism
  • Nasopharyngeal Carcinoma
  • Nasopharyngeal Neoplasms / metabolism*
  • Paclitaxel / administration & dosage
  • Protein Kinase Inhibitors / administration & dosage*
  • Proto-Oncogene Proteins c-akt / antagonists & inhibitors*
  • Proto-Oncogene Proteins c-akt / metabolism
  • TOR Serine-Threonine Kinases / metabolism

Substances

  • Antineoplastic Agents
  • Heterocyclic Compounds, 3-Ring
  • MK 2206
  • Protein Kinase Inhibitors
  • MTOR protein, human
  • Proto-Oncogene Proteins c-akt
  • TOR Serine-Threonine Kinases
  • Mitogen-Activated Protein Kinases
  • Paclitaxel
  • Cisplatin