Cationic liposomes loaded with proapoptotic peptide D-(KLAKLAK)(2) and Bcl-2 antisense oligodeoxynucleotide G3139 for enhanced anticancer therapy

Mol Pharm. May-Jun 2009;6(3):971-7. doi: 10.1021/mp900006h.

Abstract

The treatment of cancer using macromolecular therapeutics such as oligonucleotides or peptides requires efficient delivery systems capable of intracellular penetration and may also benefit from use of a combination of therapeutics with different mechanisms of action. With this possibility in mind, we constructed cationic liposome loaded with the proapoptotic peptide, d-(KLAKLAK)(2) and the Bcl-2 antisense oligodeoxynucleotide, G3139, and determined whether the combination of the proapoptotic macromolecules in a single cationic liposome can enhance antitumor efficacy. Advantage was taken of alternating charge interaction to entrap macromolecules of opposite charge. The polycationic peptide d-(KLAKLAK)(2) was first condensed with the polyanionic oligodeoxynucleotide G3139 to obtain overall negatively charged peptide/oligodeoxynucleotide complexes. The complexes were then entrapped into DOTAP/DOPE cationic liposomes (CL). This sequential charge interaction ensured efficient entrapment of d-(KLAKLAK)(2) and G3139 with a high loading efficiency (50%) and capacity (7.5 wt %). In vitro treatment of mouse melanoma B16(F10) with CL loaded with d-(KLAKLAK)(2)/G3139 led to significantly enhanced antitumor efficacy, mediated by stimulated induction of apoptotic (caspase 3/7) activity, when compared to CL loaded with G3139 alone. Intratumoral injection of CL loaded with d-(KLAKLAK)(2)/G3139 in B16(F10) mice xenograft also led to suppressed tumor growth associated with enhanced apoptotic activity. Thus, the combination of proapoptotic peptide d-(KLAKLAK)(2) and antisense oligonucleotide G3139 in a cationic liposome led to enhanced apoptotic/antitumor efficacy and may provide a promising tool for cancer treatment.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Caspase 3 / metabolism
  • Caspase 7 / metabolism
  • Cell Line, Tumor
  • DNA, Antisense / chemistry*
  • DNA, Antisense / genetics
  • DNA, Antisense / physiology*
  • Genetic Therapy / methods*
  • In Situ Nick-End Labeling
  • Liposomes / chemistry*
  • Male
  • Melanoma, Experimental / therapy*
  • Mice
  • Mice, Inbred C57BL
  • Peptide Fragments / chemistry*
  • Proto-Oncogene Proteins c-bcl-2 / genetics*

Substances

  • DNA, Antisense
  • Liposomes
  • Peptide Fragments
  • Proto-Oncogene Proteins c-bcl-2
  • Caspase 3
  • Caspase 7