Phospho-ibuprofen (MDC-917) incorporated in nanocarriers: anti-cancer activity in vitro and in vivo

Br J Pharmacol. 2012 Jun;166(3):991-1001. doi: 10.1111/j.1476-5381.2011.01799.x.


Background and purpose: Phospho-ibuprofen (P-I; MDC-917) inhibits the growth of colon cancer in mice. Here, we investigated the use of nanocarriers to improve its pharmacokinetics (PKs) and anti tumour efficacy.

Experimental approach: The cellular uptake and cytotoxicity of P-I encapsulated into liposomes and micelles, and its in vitro metabolic stability, were determined in cultures of human colon adenocarcinoma cells. The performance of liposomal P-I was further evaluated in PK studies in mice, and in a model of colon cancer xenografts in nude mice.

Key results: Liposomal P-I and micellar P-I showed significantly enhanced cellular uptake in the colon cancer cells. Liposomal P-I also demonstrated increased cytotoxicity in vitro. Free P-I was metabolized rapidly to ibuprofen in the presence of purified esterases. In contrast, liposomal P-I, and to a lesser extent micellar P-I, was resistant to esterase-mediated hydrolysis. In mice, liposomal P-I partially protected P-I from hydrolysis in the circulation, and improved the biodistribution of intact P-I and its metabolites compared to free P-I. Liposomal P-I was more effective at inhibiting the growth of human colon cancer xenografts in mice, which may be explained on the basis of its improved PK profile compared to free P-I.

Conclusions and implications: Liposome encapsulation of P-I partially protected P-I from esterase-mediated hydrolysis in mice, enhanced the cytotoxicity and bioavailability of P-I and increased its efficacy at inhibiting the growth of human colon cancer xenografts. These results indicate that liposomes are suitable nanocarriers for the delivery of P-I, and that the anti-tumour potential of liposomal P-I merits further evaluation.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Antineoplastic Agents / administration & dosage
  • Antineoplastic Agents / pharmacokinetics
  • Antineoplastic Agents / therapeutic use*
  • Cell Culture Techniques
  • Cell Line, Tumor
  • Cell Survival / drug effects
  • Colonic Neoplasms / drug therapy
  • Colonic Neoplasms / pathology
  • Drug Carriers / chemistry*
  • Drug Stability
  • Female
  • Humans
  • Ibuprofen / administration & dosage
  • Ibuprofen / analogs & derivatives*
  • Ibuprofen / pharmacokinetics
  • Ibuprofen / therapeutic use
  • Liposomes
  • Mice
  • Mice, Inbred BALB C
  • Mice, Nude
  • Micelles
  • Microscopy, Electron, Transmission
  • Molecular Structure
  • Nanostructures / chemistry*
  • Organophosphates / administration & dosage
  • Organophosphates / pharmacokinetics
  • Organophosphates / therapeutic use*
  • Particle Size
  • Surface Properties
  • Xenograft Model Antitumor Assays


  • 2-(4-isobutylphenyl)propionic acid 4-(diethoxyphosphoryloxy)butyl ester
  • Antineoplastic Agents
  • Drug Carriers
  • Liposomes
  • Micelles
  • Organophosphates
  • Ibuprofen