EGF promotes the shedding of soluble E-cadherin in an ADAM10-dependent manner in prostate epithelial cells.
During the progression of prostate cancer, the epithelial adhesion molecule E-cadherin is cleaved from the cell surface by ADAM15 proteolytic processing, generating an extracellular 80kDa fragment referred to as soluble E-cadherin (sE-cad). Contrary to observations in cancer, the generation of sE-cad appears to correlate with ADAM10 activity in benign prostatic epithelium. The ADAM10-specific inhibitor INCB8765 and the ADAM10 prodomain inhibit the generation of sE-cad, as well as downstream signaling and cell proliferation. Addition of EGF or amphiregulin (AREG) to these untransformed cell lines increases the amount of sE-cad shed into the conditioned media, as well as sE-cad bound to EGFR. EGF-associated shedding appears to be mediated by ADAM10 as shRNA knockdown of ADAM10 results in reduced shedding of sE-cad. To examine the physiologic role of sE-cad on benign prostatic epithelium, we treated BPH-1 and large T immortalized prostate epithelial cells (PrEC) with an sE-cad chimera comprised of the human Fc domain of IgG(1), fused to the extracellular domains of E-cadherin (Fc-Ecad). The treatment of untransformed prostate epithelial cells with Fc-Ecad resulted in phosphorylation of EGFR and downstream signaling through ERK and increased cell proliferation. Pre-treating BPH-1 and PrEC cells with cetuximab, a therapeutic monoclonal antibody against EGFR, decreased the ability of Fc-Ecad to induce EGFR phosphorylation, downstream signaling, and proliferation. These data suggest that ADAM10-generated sE-cad may have a role in EGFR signaling independent of traditional EGFR ligands.
Department of Urology, University of Michigan, 6131 Cancer Center, 1500 E. Medical Center Drive, Ann Arbor, MI 48109, USA; Program in Cell and Molecular Biology, 6131 Cancer Center, 1500 E. Medical Center Drive, Ann Arbor, MI 48109, USA.
Magdalena M
MM
Grabowska
Department of Urology, University of Michigan, 6131 Cancer Center, 1500 E. Medical Center Drive, Ann Arbor, MI 48109, USA.
Brindar
B
Sandhu
Department of Urology, University of Michigan, 6131 Cancer Center, 1500 E. Medical Center Drive, Ann Arbor, MI 48109, USA; Program in Cell and Molecular Biology, 6131 Cancer Center, 1500 E. Medical Center Drive, Ann Arbor, MI 48109, USA. Electronic address: mday@umich.edu.
Mark L
ML
Day
D051722:ADAM Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D000072197:ADAM10 Protein; D066258:Amphiregulin; D053829:Amyloid Precursor Protein Secretases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D061067:Antibodies, Monoclonal, Humanized; D015820:Cadherins / Q000096:biosynthesis* / Q000378:metabolism; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D000068818:Cetuximab; D066255:EGF Family of Proteins; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D006023:Glycoproteins / Q000494:pharmacology; D006801:Humans; D007074:Immunoglobulin G / Q000235:genetics / Q000494:pharmacology; D036341:Intercellular Signaling Peptides and Proteins / Q000494:pharmacology; D008297:Male; D008565:Membrane Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation / Q000187:drug effects; D011467:Prostate / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D011485:Protein Binding; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects; D012995:Solubility
C587848:AREG protein, human; D066258:Amphiregulin; D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D015820:Cadherins; D066255:EGF Family of Proteins; D004791:Enzyme Inhibitors; D006023:Glycoproteins; D007074:Immunoglobulin G; D036341:Intercellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D034741:RNA, Small Interfering; D011993:Recombinant Fusion Proteins; D004815:Epidermal Growth Factor; D066246:ErbB Receptors; D053829:Amyloid Precursor Protein Secretases; D051722:ADAM Proteins; D000072197:ADAM10 Protein; C491236:ADAM10 protein, human; D000068818:Cetuximab