title: Blockade of epidermal growth factor receptor signaling on tumor cells and tumor-associated endothelial cells for therapy of human carcinomas.
abstract: The purpose of this study was to determine whether the expression of epidermal growth factor receptor (EGF-R) and activated EGF-R by tumor-associated endothelial cells is influenced by interaction with specific growth factors in the microenvironment. Different human carcinoma cell lines expressing EGF-R with low or high levels of EGF/transforming growth factor (TGF)-alpha were implanted into orthotopic organs of nude mice. In the EGF/TGF-alpha-positive bladder cancer (253J-BV), pancreatic cancer (L3.6pl), and renal cancer (RBM1-IT) but not in the EGF/TGF-alpha-negative renal cancer SN12-PM6, tumor-associated endothelial cells expressed EGF-R and activated EGF-R. Mice were implanted with human 253J-BV bladder tumors (EGF+) or human SN12-PM6 renal tumors (EGF-). Treatment with oral PKI 166 (a specific inhibitor of EGF-R phosphorylation) alone, intraperitoneal paclitaxel alone (253J-BV), gemcitabine alone (SN12-PM6), or combination of PKI 166 and chemotherapy produced a 60%, 32%, or 81% reduction in the volume of 253J-BV bladder tumors, respectively, and 26%, 23%, or 51% reduction in the volume of SN12-PM6 kidney tumors, respectively. Immunohistochemical analyses demonstrated down-regulation of activated EGF-R in EGF/TGF-alpha-positive and EGF/TGF-alpha-negative lesions from mice treated with PKI 166, although apoptosis of tumor-associated endothelial cells was found only in EGF/TGF-alpha-positive tumors. Collectively, these data suggest that expression of activated EGF-R by tumor-associated endothelial cells provides an important target for therapy.
authors.affiliation: Department of Cancer Biology, The University of Texas M. D. Anderson Cancer Center, Houston 77030, USA.
authors.forename: Cheryl H
authors.initials: CH
authors.lastname: Baker
authors.forename: Daniel
authors.initials: D
authors.lastname: Kedar
authors.forename: Marya F
authors.initials: MF
authors.lastname: McCarty
authors.forename: Rachel
authors.initials: R
authors.lastname: Tsan
authors.forename: Kristen L
authors.initials: KL
authors.lastname: Weber
authors.forename: Corazon D
authors.initials: CD
authors.lastname: Bucana
authors.forename: Isaiah J
authors.initials: IJ
authors.lastname: Fidler
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage; D003841:Deoxycytidine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D066246:ErbB Receptors / Q000037:antagonists & inhibitors*; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D009374:Neoplasms, Experimental / Q000098:blood supply / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology; D009389:Neovascularization, Pathologic / Q000188:drug therapy; D017239:Paclitaxel / Q000008:administration & dosage; D011743:Pyrimidines / Q000008:administration & dosage; D011758:Pyrroles / Q000008:administration & dosage; D015398:Signal Transduction / Q000187:drug effects*; D014407:Tumor Cells, Cultured; D000093542:Gemcitabine
chemical_list: D000970:Antineoplastic Agents; D011743:Pyrimidines; D011758:Pyrroles; D003841:Deoxycytidine; C410026:PKI 166; D066246:ErbB Receptors; D017239:Paclitaxel; D000093542:Gemcitabine