title: Pigment Epithelium-derived Factor (PEDF) Blocks Wnt3a Protein-induced Autophagy in Pancreatic Intraepithelial Neoplasms.
abstract: An increase in autophagy characterizes pancreatic carcinogenesis, but the signals that regulate this process are incompletely understood. Because canonical Wnt/β-catenin signaling is necessary for the transition from early to advanced pancreatic intraepithelial neoplasia (PanIN) lesions, we assessed whether Wnt ligands and endogenous inhibitors of Wnt signaling modulate autophagy. In this study, canonical Wnt3a ligand induced autophagy markers and vacuoles in murine PanIN cells. Furthermore, pigment epithelium-derived factor (PEDF), a secreted glycoprotein known for its anti-tumor properties, blocked Wnt3a-directed induction of autophagy proteins. Autophagy inhibition was complemented by reciprocal regulation of the oxidative stress enzymes, superoxide dismutase 2 (SOD2) and catalase. Transcriptional control of Sod2 expression was mediated by PEDF-induced NFκB nuclear translocation. PEDF-dependent SOD2 expression in PanIN lesions was recapitulated in a murine model of PanIN formation where PEDF was deleted. In human PanIN lesions, co-expression of PEDF and SOD2 was observed in the majority of early PanIN lesions (47/50, 94%), whereas PEDF and SOD2 immunolocalization in high-grade human PanIN-2/3 was uncommon (7/50, 14%). These results indicate that PEDF regulates autophagy through coordinate Wnt signaling blockade and NFκB activation.
authors.affiliation: From the Departments of Medicine and.
authors.forename: Jingjing
authors.initials: J
authors.lastname: Gong
authors.affiliation: From the Departments of Medicine and.
authors.forename: Glenn
authors.initials: G
authors.lastname: Belinsky
authors.affiliation: the Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516.
authors.forename: Usman
authors.initials: U
authors.lastname: Sagheer
authors.affiliation: the Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516 Pathology, Yale University School of Medicine, New Haven, Connecticut 06520.
authors.forename: Xuchen
authors.initials: X
authors.lastname: Zhang
authors.affiliation: the Department of Medicine, University of Illinois School of Medicine, Chicago, Illinois 60612, and.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Grippo
authors.affiliation: From the Departments of Medicine and the Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516 chuhan.chung@yale.edu.
authors.forename: Chuhan
authors.identifier: http://orcid.org/0000-0003-2803-6745
authors.initials: C
authors.lastname: Chung
mesh_terms: D000818:Animals; D001343:Autophagy; D002374:Catalase / Q000096:biosynthesis; D045744:Cell Line, Tumor; D005136:Eye Proteins / Q000378:metabolism*; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D051379:Mice; D008822:Mice, Transgenic; D009363:Neoplasm Proteins / Q000378:metabolism*; D009414:Nerve Growth Factors / Q000378:metabolism*; D010190:Pancreatic Neoplasms / Q000378:metabolism* / Q000473:pathology; D015843:Serpins / Q000378:metabolism*; D013482:Superoxide Dismutase / Q000096:biosynthesis; D060449:Wnt Signaling Pathway; D060509:Wnt3A Protein / Q000378:metabolism*; D000099174:Pigment Epithelium-Derived Factor; D000099156:Superoxide Dismutase 2
chemical_list: D002374:Catalase; D005136:Eye Proteins; D009363:Neoplasm Proteins; D009414:Nerve Growth Factors; D015843:Serpins; D013482:Superoxide Dismutase; D060509:Wnt3A Protein; D000099174:Pigment Epithelium-Derived Factor; D000099156:Superoxide Dismutase 2; C555510:WNT3A protein, human; C555511:Wnt3a protein, mouse
keywords: NFκB (NFκB); PEDF; autophagy; catalase; pancreas; superoxide dismutase (SOD)