title: Leucine leucine-37 uses formyl peptide receptor-like 1 to activate signal transduction pathways, stimulate oncogenic gene expression, and enhance the invasiveness of ovarian cancer cells.
abstract: Emerging evidence suggests that the antimicrobial peptide, leucine leucine-37 (LL-37), could play a role in the progression of solid tumors. LL-37 is expressed as the COOH terminus of human cationic antimicrobial protein-18 (hCAP-18) in ovarian, breast, and lung cancers. Previous studies have shown that the addition of LL-37 to various cancer cell lines in vitro stimulates proliferation, migration, and invasion. Similarly, overexpression of hCAP-18/LL-37 in vivo accelerates tumor growth. However, the receptor or receptors through which these processes are mediated have not been thoroughly examined. In the present study, expression of formyl peptide receptor-like 1 (FPRL1) was confirmed on ovarian cancer cells. Proliferation assays indicated that LL-37 does not signal through a G protein-coupled receptor, such as FPRL1, to promote cancer cell growth. By contrast, FPRL1 was required for LL-37-induced invasion through Matrigel. The peptide stimulated mitogen-activated protein kinase and Janus-activated kinase/signal transducers and activators of transcription signaling cascades and led to the significant activation of several transcription factors, through both FPRL1-dependent and FPRL1-independent pathways. Likewise, expression of some LL-37-stimulated genes was attenuated by the inhibition of FPRL1. Increased expression of CXCL10, EGF, and PDGF-BB as well as other soluble factors was confirmed from conditioned medium of LL-37-treated cells. Taken together, these data suggest that LL-37 potentiates a more aggressive behavior from ovarian cancer cells through its interaction with FPRL1.
authors.affiliation: University of Sheffield School of Medicine, UK. s.coffelt@sheffield.ac.uk
authors.forename: Seth B
authors.initials: SB
authors.lastname: Coffelt
authors.forename: Suzanne L
authors.initials: SL
authors.lastname: Tomchuck
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Zwezdaryk
authors.forename: Elizabeth S
authors.initials: ES
authors.lastname: Danka
authors.forename: Aline B
authors.initials: AB
authors.lastname: Scandurro
mesh_terms: D023181:Antimicrobial Cationic Peptides / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D045744:Cell Line, Tumor; D005260:Female; D005434:Flow Cytometry; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects*; D006801:Humans; D020935:MAP Kinase Signaling System / Q000502:physiology*; D009361:Neoplasm Invasiveness; D009857:Oncogenes; D010051:Ovarian Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D034741:RNA, Small Interfering / Q000235:genetics; D044042:Receptors, Formyl Peptide / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism; D044067:Receptors, Lipoxin / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins / Q000494:pharmacology; D054804:Cathelicidins
chemical_list: D023181:Antimicrobial Cationic Peptides; C105101:FPR2 protein, human; D034741:RNA, Small Interfering; D044042:Receptors, Formyl Peptide; D043562:Receptors, G-Protein-Coupled; D044067:Receptors, Lipoxin; D011994:Recombinant Proteins; D054804:Cathelicidins