Enhanced killing of breast cancer cells by a d-amino acid analog of the winter flounder-derived pleurocidin NRC-03

Ashley L. Hilchie, Evan F. Haney, Devanand M. Pinto, Robert E.W. Hancock, David W. Hoskin

Research output: Contribution to journalArticlepeer-review

18 Citations (Scopus)


Cationic antimicrobial peptides (CAPs) defend against pathogens and, in some cases, exhibit potent anticancer activities. We previously reported that the pleurocidin NRC-03 causes lysis of breast cancer and multiple myeloma cells. NRC-03 also reduces the EC50 of other cytotoxic compounds and prevents tumor growth in vivo. However, the therapeutic utility of NRC-03 may be limited by its susceptibility to degradation by proteases. The goal of this study was to characterize the anticancer activities of a d-amino acid analog of NRC-03 ([D]-NRC-03) that was predicted to be resistant to proteolytic degradation. Unlike NRC-03, [D]-NRC-03 was not degraded by human serum or trypsin and, in comparison to NRC-03, showed increased killing of breast cancer cells, including multidrug-resistant cells; however, [D]-NRC-03 was somewhat more cytotoxic than NRC-03 for several types of normal cells. Importantly, [D]-NRC-03 was more effective than NRC-03 in vivo since 4-fold less peptide was required for an equivalent inhibitory effect on the growth of breast cancer cell xenografts in immune-deficient mice. These findings demonstrate that a d-amino acid analog of NRC-03 overcomes a major limitation to the therapeutic use of NRC-03, namely peptide stability. Further modification of [D]-NRC-03 is required to improve its selectivity for cancer cells.

Original languageEnglish
Pages (from-to)426-434
Number of pages9
JournalExperimental and Molecular Pathology
Issue number3
Publication statusPublished or Issued - 1 Dec 2015
Externally publishedYes


  • Antimicrobial peptide
  • Breast cancer
  • Cytotoxicity
  • D-amino acid
  • Pleurocidin

ASJC Scopus subject areas

  • Pathology and Forensic Medicine
  • Molecular Biology
  • Clinical Biochemistry

Cite this