TACE cleavage of proamphiregulin regulates GPCR-induced proliferation and motility of cancer cells.
Communication between G protein-coupled receptor (GPCR) and epidermal growth factor receptor (EGFR) signalling systems involves cell surface proteolysis of EGF-like precursors. The underlying mechanisms of EGFR signal transactivation pathways, however, are largely unknown. We demonstrate that in squamous cell carcinoma cells, stimulation with the GPCR agonists LPA or carbachol specifically results in metalloprotease cleavage and release of amphiregulin (AR). Moreover, AR gene silencing by siRNA or inhibition of AR biological activity by neutralizing antibodies and heparin prevents GPCR-induced EGFR tyrosine phosphorylation, downstream mitogenic signalling events, cell proliferation, migration and activation of the survival mediator Akt/PKB. Therefore, despite some functional redundancy among EGF family ligands, the present study reveals a distinct and essential role for AR in GPCR-triggered cellular responses. Furthermore, we present evidence that blockade of the metalloprotease-disintegrin tumour necrosis factor-alpha-converting enzyme (TACE) by the tissue inhibitor of metalloprotease-3, a dominant-negative TACE mutant or RNA interference suppresses GPCR-stimulated AR release, EGFR activation and downstream events. Thus, TACE can function as an effector of GPCR-mediated signalling and represents a key element of the cellular receptor cross-talk network.
Department of Molecular Biology, Max-Planck Institute of Biochemistry, Am Klopferspitz 18A, D-82152 Martinsried, Germany.
Andreas
A
Gschwind
Stefan
S
Hart
Oliver M
OM
Fischer
Axel
A
Ullrich
D051722:ADAM Proteins; D000072198:ADAM17 Protein; D066258:Amphiregulin; D000906:Antibodies / Q000378:metabolism; D002217:Carbachol / Q000378:metabolism; D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000473:pathology; D002455:Cell Division / Q000502:physiology; D002465:Cell Movement / Q000502:physiology*; D066255:EGF Family of Proteins; D004789:Enzyme Activation; D066246:ErbB Receptors / Q000378:metabolism; D019204:GTP-Binding Proteins / Q000378:metabolism*; D006023:Glycoproteins / Q000378:metabolism*; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism*; D008024:Ligands; D008246:Lysophospholipids / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D008666:Metalloendopeptidases / Q000235:genetics / Q000378:metabolism*; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D011498:Protein Precursors / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt; D034741:RNA, Small Interfering / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology; D014407:Tumor Cells, Cultured
C587848:AREG protein, human; D066258:Amphiregulin; D000906:Antibodies; D066255:EGF Family of Proteins; D006023:Glycoproteins; D036341:Intercellular Signaling Peptides and Proteins; D008024:Ligands; D008246:Lysophospholipids; D008565:Membrane Proteins; D011498:Protein Precursors; D011518:Proto-Oncogene Proteins; D034741:RNA, Small Interfering; D011956:Receptors, Cell Surface; D002217:Carbachol; D066246:ErbB Receptors; C494918:AKT1 protein, human; D017346:Protein Serine-Threonine Kinases; D051057:Proto-Oncogene Proteins c-akt; D020928:Mitogen-Activated Protein Kinases; D051722:ADAM Proteins; D008666:Metalloendopeptidases; D000072198:ADAM17 Protein; C000606462:ADAM17 protein, human; D019204:GTP-Binding Proteins