Identification of BP16 as a non-toxic cell-penetrating peptide with highly efficient drug delivery properties.
Antimicrobial peptides are an interesting source of non-cytotoxic drug delivery vectors. Herein, we report on the identification of a new cell-penetrating peptide (KKLFKKILKKL-NH2, BP16) from a set of antimicrobial peptides selected from a library of cecropin-melittin hybrids (CECMEL11) previously designed to be used in plant protection. This set of peptides was screened for their cytotoxicity against breast adenocarcinoma MCF-7, pancreas adenocarcinoma CAPAN-1 and mouse embryonic fibroblast 3T3 cell lines. BP16 resulted to be non-toxic against both malignant and non-malignant cells at concentrations up to 200 μM. We demonstrated by flow cytometry and confocal microscopy that BP16 is mainly internalized in the cells through a clathrin dependent endocytosis and that it efficiently accumulates in the cell cytoplasm. We confirmed that the cell-penetrating properties of BP16 are retained after conjugating it to the breast tumor homing peptide CREKA. Furthermore, we assessed the potential of BP16 as a drug delivery vector by conjugating the anticancer drug chlorambucil to BP16 and to a CREKA-BP16 conjugate. The efficacy of the drug increased between 6 and 9 times when conjugated to BP16 and between 2 and 4.5 times when attached to the CREKA-BP16 derivative. The low toxicity and the excellent cell-penetrating properties clearly suggest that BP16 is a suitable vector for the delivery of therapeutic agents into cells.
QBIS-CAT Research Group, Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona, Campus Montilivi, E-17071 Girona, Catalonia, Spain.
Marta
M
Soler
Marta
M
González-Bártulos
David
D
Soriano-Castell
Xavi
X
Ribas
Miquel
M
Costas
Francesc
F
Tebar
Anna
A
Massaguer
Lidia
L
Feliu
Marta
M
Planas
D016475:3T3 Cells; D000818:Animals; D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D057846:Cell-Penetrating Peptides / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D016503:Drug Delivery Systems; D015195:Drug Design; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D061986:MCF-7 Cells; D051379:Mice; D013329:Structure-Activity Relationship
D000970:Antineoplastic Agents; D057846:Cell-Penetrating Peptides