Design and biological evaluation of cell-penetrating peptide-doxorubicin conjugates as prodrugs

Mol Pharm. 2013 Feb 4;10(2):488-99. doi: 10.1021/mp3004034. Epub 2013 Jan 15.


Doxorubicin (Dox) is a hydrophilic anticancer drug that has short retention time due to the efficient efflux in some cancer cells (e.g., ovarian adenocarcinoma SK-OV-3). Cyclic [W(RW)(4)] and the corresponding linear peptide (RW)(4) were conjugated with Dox through an appropriate linker to afford cyclic [W(RW)(4)]-Dox and linear (RW)(4)-Dox conjugates to enhance the cellular uptake and cellular retention of the parent drug for sustained anticancer activity. Comparative antiproliferative assays between covalent (cyclic [W(RW)(4)]-Dox and linear (RW)(4)-Dox) and the corresponding noncovalent physical mixtures of the peptides and Dox were performed. Cyclic [W(RW)(4)]-Dox inhibited the cell proliferation of human leukemia (CCRF-CEM) (62-73%), ovarian adenocarcinoma (SK-OV-3) (51-74%), colorectal carcinoma (HCT-116) (50-67%), and breast carcinoma (MDA-MB-468) (60-79%) cells at a concentration of 1 μM after 72-120 h of incubation. Cyclic [W(RW)(4)]-Dox exhibited higher antiproliferative activity than linear (RW)(4)-Dox in all cancer cells with the highest activity observed after 72 h. Flow cytometry analysis showed 3.6-fold higher cellular uptake of cyclic [W(RW)(4)]-Dox than Dox alone in SK-OV-3 cells after 24 h incubation. The cellular hydrolysis study showed that 99% of cyclic [W(RW)(4)]-Dox was hydrolyzed intracellularly within 72 h and released Dox. These data suggest that cyclic [W(RW)(4)]-Dox can be used as a potential prodrug for improving the cellular delivery and retention of Dox.

Publication types

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

MeSH terms

  • Cell-Penetrating Peptides / chemistry*
  • Cell-Penetrating Peptides / metabolism*
  • Doxorubicin / chemistry*
  • Doxorubicin / metabolism*
  • Drug Design
  • Mesalamine / chemistry
  • Mesalamine / metabolism
  • Molecular Structure
  • Prodrugs / chemistry*
  • Prodrugs / metabolism*


  • Cell-Penetrating Peptides
  • Prodrugs
  • Mesalamine
  • Doxorubicin