title: Ligand-dependent EGFR activation induces the co-expression of IL-6 and PAI-1 via the NFkB pathway in advanced-stage epithelial ovarian cancer.
abstract: The epidermal growth factor receptor (EGFR), a member of the ErbB family of receptor tyrosine kinases, is expressed in up to 70% of epithelial ovarian cancers (EOCs), where it correlates with poor prognosis. The majority of EOCs are diagnosed at an advanced stage, and at least 50% present malignant ascites. High levels of IL-6 have been found in the ascites of EOC patients and correlate with shorter survival. Herein, we investigated the signaling cascade led by EGFR activation in EOC and assessed whether EGFR activation could induce an EOC microenvironment characterized by pro-inflammatory molecules. In vitro analysis of EOC cell lines revealed that ligand-stimulated EGFR activated NFkB-dependent transcription and induced secretion of IL-6 and plasminogen activator inhibitor (PAI-1). IL-6/PAI-1 expression and secretion were strongly inhibited by the tyrosine kinase inhibitor AG1478 and EGFR silencing. A significant reduction of EGF-stimulated IL-6/PAI-1 secretion was also obtained with the NFkB inhibitor dehydroxymethylepoxyquinomicin. Of 23 primary EOC tumors from advanced-stage patients with malignant ascites at surgery, 12 co-expressed membrane EGFR, IL-6 and PAI-1 by immunohistochemistry; both IL-6 and PAI-1 were present in 83% of the corresponding ascites. Analysis of a publicly available gene-expression data set from 204 EOCs confirmed a significant correlation between IL-6 and PAI-1 expression, and patients with the highest IL-6 and PAI-1 co-expression showed a significantly shorter progression-free survival time (P=0.028). This suggests that EGFR/NFkB/IL-6-PAI-1 may have a significant impact on the therapy of a particular subset of EOC, and that IL-6/PAI-1 co-expression may be a novel prognostic marker.
authors.affiliation: Unit of Molecular Therapies, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Alberti
authors.forename: P
authors.initials: P
authors.lastname: Pinciroli
authors.forename: B
authors.initials: B
authors.lastname: Valeri
authors.forename: R
authors.initials: R
authors.lastname: Ferri
authors.forename: A
authors.initials: A
authors.lastname: Ditto
authors.forename: K
authors.initials: K
authors.lastname: Umezawa
authors.forename: M
authors.initials: M
authors.lastname: Sensi
authors.forename: S
authors.initials: S
authors.lastname: Canevari
authors.forename: A
authors.initials: A
authors.lastname: Tomassetti
mesh_terms: D001549:Benzamides / Q000494:pharmacology; D014408:Biomarkers, Tumor / Q000235:genetics; D000077216:Carcinoma, Ovarian Epithelial; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D003512:Cyclohexanones / Q000494:pharmacology; D018572:Disease-Free Survival; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D005260:Female; D006801:Humans; D015850:Interleukin-6 / Q000096:biosynthesis* / Q000378:metabolism; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000378:metabolism*; D009375:Neoplasms, Glandular and Epithelial / Q000378:metabolism* / Q000401:mortality; D010051:Ovarian Neoplasms / Q000378:metabolism* / Q000401:mortality; D017395:Plasminogen Activator Inhibitor 1 / Q000096:biosynthesis* / Q000378:metabolism; D011799:Quinazolines / Q000494:pharmacology; D034622:RNA Interference; D034741:RNA, Small Interfering; D015398:Signal Transduction; D059016:Tumor Microenvironment; D020032:Tyrphostins / Q000494:pharmacology
chemical_list: D001549:Benzamides; D014408:Biomarkers, Tumor; D003512:Cyclohexanones; D015850:Interleukin-6; D016328:NF-kappa B; D017395:Plasminogen Activator Inhibitor 1; D011799:Quinazolines; D034741:RNA, Small Interfering; C051321:SERPINE1 protein, human; D020032:Tyrphostins; C464444:dehydroxymethylepoxyquinomicin; C101044:RTKI cpd; D066246:ErbB Receptors