Characterization of a novel cytotoxic cell-penetrating peptide derived from p14ARF protein.

Journal article

The tumor suppressor p14ARF is widely deregulated in many types of cancers and is believed to function as a failsafe mechanism, inhibiting proliferation and inducing apoptosis as cellular response to a high oncogene load. We have found that a 22-amino-acid-long peptide derived from the N-terminal part of p14ARF, denoted ARF(1-22), which has previously been shown to mimic the function of p14ARF, has cell-penetrating properties. This peptide is internalized to the same extent as the cell-penetrating peptide (CPP) TP10 and dose-dependently decreases proliferation in MCF-7 and MDA MB 231 cells. Uptake of the ARF(1-22) peptide is associated with low membrane disturbance, measured by deoxyglucose and lactate dehydrogenase (LDH) leakage, as compared to its scrambled peptide. Also, flow cytometric analysis of annexin V/propidium iodide (PI) binding and Hoechst staining of nuclei suggest that ARF(1-22) induces apoptosis, whereas scrambled or inverted peptide sequences have no effect. The ARF(1-22) peptide mainly translocates cells through endocytosis, and is found intact inside cells for at least 3 hours. To our knowledge, this is the first time a CPP having pro-apoptopic activity has been designed from a protein.

Authors: Johansson, H; El-Andaloussi, S; Holm, T; Mäe, M; Jänes, J

• Journal: Molecular therapy : the journal of the American Society of Gene Therapy
• Volume: 16
• Issue: 1
• Pages: 115-123
• Publication date: 2008-01-01
• DOI: 10.1038/sj.mt.6300346
• EISSN: 1525-0024
• ISSN: 1525-0016
• Language: English
• Keywords: Molecular Sequence Data; Cell Proliferation; Humans; Cell Line, Tumor; Molecular Mimicry; Peptides; Hela Cells; Peptide Nucleic Acids; Cytotoxins; Cell Membrane Permeability; Tumor Suppressor Protein p14ARF; Amino Acid Sequence; Apoptosis