Combined effect of rapamycin and cisplatin on survival of Hep-2 cells in vitro

Oncol Res. 2009;18(2-3):73-81. doi: 10.3727/096504009789954618.

Abstract

The cytotoxic effects and mechanism of action of cisplatin and the mTOR inhibitor rapamycin on Hep-2 laryngeal cancer cells were investigated. Hep-2 cells were cultured in the presence of different concentrations of rapamycin, cisplatin, or the two combined. Inhibition of cell growth, apoptosis, and AKT, mTOR, S6K, and ERCC1 protein levels were assessed. All combinations of rapamycin and cisplatin resulted in synergistic inhibition of cell growth (as indicated by q values determined using Jin's formula > 1.15). Rapamycin inhibited Hep-2 cell growth, induced G1 arrest, and when combined with cisplatin, enhanced apoptosis. p-mTOR and S6K expressions were significantly downregulated by rapamycin. ERCC1 expression was significantly upregulated with cisplatin treatment. Combined cisplatin and rapamycin treatment resulted in significant downregulated p-mTOR and S6K expression, but no change in ERCC1 expression. Rapamycin and cisplatin act in a synergistic manner, increasing the cytotoxic effect on Hep-2 cells. Rapamycin may facilitate increased Hep-2 cell apoptosis with cisplatin via inhibiting downstream expression of proteins in the AKT-mTOR signaling pathway.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Agents / pharmacology*
  • Apoptosis / drug effects
  • Carcinoma, Squamous Cell / drug therapy*
  • Carcinoma, Squamous Cell / pathology
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Cell Survival / drug effects
  • Cisplatin / pharmacology*
  • DNA-Binding Proteins / analysis
  • Drug Synergism
  • Endonucleases / analysis
  • Humans
  • Laryngeal Neoplasms / drug therapy*
  • Laryngeal Neoplasms / pathology
  • Protein Kinases / physiology
  • Ribosomal Protein S6 Kinases / analysis
  • Sirolimus / pharmacology*
  • TOR Serine-Threonine Kinases

Substances

  • Antineoplastic Agents
  • DNA-Binding Proteins
  • Protein Kinases
  • MTOR protein, human
  • Ribosomal Protein S6 Kinases
  • TOR Serine-Threonine Kinases
  • ERCC1 protein, human
  • Endonucleases
  • Cisplatin
  • Sirolimus