Laminin alpha5 chain metastasis- and angiogenesis-inhibiting peptide blocks fibroblast growth factor 2 activity by binding to the heparan sulfate chains of CD44.
Recently, we reported that the laminin alpha5 synthetic peptide A5G27 (RLVSYNGIIFFLK, residues 2,892-2,904) binds to the CD44 receptor of B16-F10 melanoma cells via the glycosaminoglycans on CD44 and inhibits tumor cell migration, invasion, and angiogenesis in a dominant-negative manner. Here, we have identified the potential mechanism of A5G27 activity using WiDr human colorectal carcinoma cells. WiDr cells bound to the laminin A5G27 peptide via the heparin-like and chondroitin sulfate B glycosaminoglycan side chains of CD44. Cell binding to fibroblast growth factor (FGF2) was blocked by laminin peptide A5G27 but not by either a scrambled version of this peptide or by another laminin peptide known to bind cell surface proteoglycans. FGF2 signaling involving tyrosine phosphorylation was also blocked by laminin peptide A5G27 but was not affected by peptide controls. Finally, we have shown that peptide A5G27 directly blocks FGF2 binding to heparin. Peptide A5G27 has sequence homology to a region on FGF2 that binds heparin and the FGF receptor and is important in FGF2 central cavity formation. We conclude that peptide A5G27 inhibits metastasis and angiogenesis by blocking FGF2 binding to the heparan sulfate side chains of CD44 variant 3, thus decreasing FGF2 bioactivity.
Hibino
Suguru
S
Craniofacial Developmental Biology and Regeneration Branch, National Institute of Dental and Craniofacial Research, NIH, Bethesda, Maryland 20892-4370, USA.
Shibuya
Masahiko
M
Hoffman
Matthew P
MP
Engbring
Jean A
JA
Hossain
Rydhwana
R
Mochizuki
Mayumi
M
Kudoh
Shoji
S
Nomizu
Motoyoshi
M
Kleinman
Hynda K
HK
D000595:Amino Acid Sequence; D000906:Antibodies / Q000737:chemistry; D000918:Antibody Specificity; D045744:Cell Line, Tumor; D015179:Colorectal Neoplasms / Q000098:blood supply / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D016222:Fibroblast Growth Factor 2 / Q000037:antagonists & inhibitors* / Q000378:metabolism; D005434:Flow Cytometry; D006023:Glycoproteins / Q000096:biosynthesis / Q000276:immunology / Q000378:metabolism; D006497:Heparan Sulfate / Q000378:metabolism*; D006801:Humans; D018960:Hyaluronan Receptors / Q000096:biosynthesis / Q000276:immunology / Q000378:metabolism*; D007797:Laminin / Q000378:metabolism / Q000494:pharmacology*; D008969:Molecular Sequence Data; D009362:Neoplasm Metastasis; D009389:Neovascularization, Pathologic / Q000188:drug therapy; D010446:Peptide Fragments / Q000378:metabolism / Q000494:pharmacology*; D010766:Phosphorylation / Q000187:drug effects; D011485:Protein Binding / Q000187:drug effects
D000906:Antibodies; D016222:Fibroblast Growth Factor 2; D006023:Glycoproteins; D006497:Heparan Sulfate; D018960:Hyaluronan Receptors; D007797:Laminin; D010446:Peptide Fragments; C121450:CD44V3,8-10; C112697:CD44v6 antigen; C097043:laminin alpha5