Lactoferrin (LF) is a mammalian host defense glycoprotein with diverse biological activities. Peptides derived from the cationic region of LF possess cytotoxic activity against cancer cells in vitro and in vivo. Bovine lactoferricin (LFcinB)， a peptide derived from bovine LF (bLF)， exhibits broad-spectrum anticancer activity， while a similar peptide derived from human LF (hLF) is not as active. In this work， several peptides derived from the N-terminal regions of bLF and hLF were studied for their anticancer activities against leukemia and breast-cancer cells， as well as normal peripheral blood mononuclear cells. The cyclized LFcinB-CLICK peptide， which possesses a stable triazole linkage， showed ... More
Lactoferrin (LF) is a mammalian host defense glycoprotein with diverse biological activities. Peptides derived from the cationic region of LF possess cytotoxic activity against cancer cells in vitro and in vivo. Bovine lactoferricin (LFcinB)， a peptide derived from bovine LF (bLF)， exhibits broad-spectrum anticancer activity， while a similar peptide derived from human LF (hLF) is not as active. In this work， several peptides derived from the N-terminal regions of bLF and hLF were studied for their anticancer activities against leukemia and breast-cancer cells， as well as normal peripheral blood mononuclear cells. The cyclized LFcinB-CLICK peptide， which possesses a stable triazole linkage， showed improved anticancer activity， while short peptides hLF11 and bLF10 were not cytotoxic to cancer cells. Interestingly， hLF11 can act as a cell-penetrating peptide; when combined with the antimicrobial core sequence of LFcinB (RRWQWR) through either a Pro or Gly-Gly linker， toxicity to Jurkat cells increased. Together， our work extends the library of LF-derived peptides tested for anticancer activity， and identified new chimeric peptides with high cytotoxicity towards cancerous cells. Additionally， these results support the notion that short cell-penetrating peptides and antimicrobial peptides can be combined to create new adducts with increased potency.
