title: HIF-1α and VEGF expression correlates with thrombus remodeling in cases of intravascular papillary endothelial hyperplasia.
abstract: Intravascular papillary endothelial hyperplasia (IPEH) is histopathologically characterized by endothelium-lined papillary structures encircling an acellular fibrin core. The process of IPEH pathogenesis is unclear. The purpose of our study was to identify histopathological and immunohistochemical characteristics of IPEH to better understand the pathogenesis of this disease. After reviewing microscopic and medical records from Kyungpook National University Hospital, we selected 16 cases of IPEH. Masson's trichrome and immunohistochemical staining as well as hematoxylin-eosin staining for 16 cases of IPH were performed. Immunohistochemical studies included CD31, CD68, mast cell tryptase, hypoxia-inducible factor-1 (HIF-1α), and vascular endothelial growth factor (VEGF). Sections from all our cases showed three distinct histological regions including a papillary portion with hyalinized fibrous or fibroblastic cores, an area containing an unorganized thrombus, and organization area with an ingrowth of endothelial cells, myofibroblasts, and fibroblasts. In the organization area, HIF-1α-positive cells were identified in the loose connective tissue. Endothelial cells forming vascular channels were negative for HIF-1α while VEGF was highly expressed in both interstitial mononuclear and endothelial cells. In the papillary portion, the cellular cores were strongly positive for both HIF-1α and VEGF, but the acellular cores were negative. Our investigation confirmed that IPEH is a reactive lesion that incidentally arises during the organization process of older thrombi. It was also found that HIF-1α and VEGF expression was dependent on the thrombus remodeling stage in cases of IPEH.
authors.affiliation: Department of Pathology, Kyungpook National University Hospital, Kyungpook National University School of Medicine Daegu, South Korea.
authors.forename: Sunzoo
authors.initials: S
authors.lastname: Kim
authors.forename: Jae Hun
authors.initials: JH
authors.lastname: Jun
authors.forename: Jeongshik
authors.initials: J
authors.lastname: Kim
authors.forename: Do Won
authors.initials: DW
authors.lastname: Kim
authors.forename: Yong Hyun
authors.initials: YH
authors.lastname: Jang
authors.forename: Weon Ju
authors.initials: WJ
authors.lastname: Lee
authors.forename: Ho Yun
authors.initials: HY
authors.lastname: Chung
authors.forename: Seok-Jong
authors.initials: SJ
authors.lastname: Lee
mesh_terms: D000293:Adolescent; D000328:Adult; D015687:Cell Hypoxia; D049109:Cell Proliferation; D002648:Child; D004730:Endothelium, Vascular / Q000737:chemistry* / Q000473:pathology; D005260:Female; D006785:Hospitals, University; D006801:Humans; D006965:Hyperplasia; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000032:analysis*; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D056910:Republic of Korea; D013927:Thrombosis / Q000378:metabolism* / Q000473:pathology; D042461:Vascular Endothelial Growth Factor A / Q000032:analysis*; D055815:Young Adult
chemical_list: C497442:HIF1A protein, human; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A
keywords: HIF-1α; VEGF; hypoxia; intravascular papillary endothelial hyperplasia; thrombus