Small-molecule inhibition of oncogenic eukaryotic protein translation in mesothelioma cells

Invest New Drugs. 2014 Aug;32(4):598-603. doi: 10.1007/s10637-014-0076-7. Epub 2014 Apr 9.

Abstract

Deranged cap-mediated translation is implicated in the genesis, maintenance and progression of many human cancers including mesothelioma. In this study, disrupting the eIF4F complex by antagonizing the eIF4E-mRNA-cap interaction is assessed as a therapy for mesothelioma. Mesothelioma cells were treated with 4Ei-1, a membrane permeable prodrug that when converted to the active drug, 7-benzyl guanosine monophosphate (7Bn-GMP) displaces capped mRNAs from the eIF4F complex. Colony formation was measured in mesothelioma treated with 4Ei-1 alone or combined with pemetrexed. Proliferation was examined in cells treated with 4Ei-1. Binding to a synthetic cap-analogue was used to study the strength of eIF4F complex activation in lysates exposed to 4Ei-1. 4Ei-1 treatment resulted in a dose dependent decrease in colony formation and cell viability. Combination therapy of 4Ei-1 with pemetrexed further reduced colony number. Formation of eIF4F cap-complex decreased in response to 4Ei-1 exposure. 4Ei-1 is a novel prodrug that reduces proliferation, represses colony formation, diminishes association of eIF4F with the mRNA cap, and sensitizes mesothelioma cells to pemetrexed.

MeSH terms

  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Cell Proliferation / genetics
  • Cell Survival / drug effects
  • Cell Survival / genetics
  • Eukaryotic Initiation Factor-4E / antagonists & inhibitors
  • Eukaryotic Initiation Factor-4F / antagonists & inhibitors
  • Glutamates / pharmacology
  • Guanine / analogs & derivatives
  • Guanine / pharmacology
  • Humans
  • Mesothelioma / drug therapy*
  • Mesothelioma / genetics
  • Oncogene Proteins / antagonists & inhibitors*
  • Oncogene Proteins / genetics
  • Pemetrexed
  • Prodrugs / pharmacology*
  • Protein Biosynthesis / drug effects*
  • Protein Biosynthesis / genetics
  • RNA, Messenger / genetics

Substances

  • Eukaryotic Initiation Factor-4E
  • Eukaryotic Initiation Factor-4F
  • Glutamates
  • Oncogene Proteins
  • Prodrugs
  • RNA, Messenger
  • Pemetrexed
  • Guanine