title: A hydrogel-endothelial cell implant mimics infantile hemangioma: modulation by survivin and the Hippo pathway.
abstract: Microvascular endothelial cells cultured in three-dimensional hydrogel scaffolds form a network of microvessel structures when implanted subcutaneously in mice, inosculate with host vessels, and over time remodel into large ectatic vascular structures resembling hemangiomas. When compared with infantile hemangiomas, similarities were noted, including a temporal progression from a morphological appearance of a proliferative phase to the appearance of an involuted phase, mimicking the proliferative and involutional phases of infantile hemangioma. Consistent with the progression of a proliferative phase to an involuted phase, both the murine implants and human biopsy tissue exhibit reduced expression of Ajuba, YAP, and Survivin labeling as they progressed over time. Significant numbers of CD45+, CD11b+, Mac3+ mononuclear cells were found at the 2-week time point in our implant model that correlated with the presence of CD45+, CD68+ mononuclear cells observed in biopsies of human proliferative-phase hemangiomas. At the 4-week time point in our implant model, only small numbers of CD45+ cells were detected, which again correlated with our findings of significantly diminished CD45+, CD68+ mononuclear cells in human involutional-phase hemangiomas. The demonstration of mononuclear cell infiltration transiently in the proliferative phase of these lesions suggests that the vascular proliferation and/or regression may be driven in part by an immune response. Gross and microscopic morphological appearances of human proliferative and involutional hemangiomas and our implant model correlate well with each other as do the expression levels of Hippo pathway components (Ajuba and YAP) and Survivin and correlate with proliferation in these entities. Inhibitors of Survivin and Ajuba (which we have demonstrated to inhibit proliferation and increase apoptosis in murine hemangioendothelioma cell tissue culture) may have potential as other beneficial treatments for proliferating infantile hemangiomas. This implant model may have potential as a modest through-put screen for testing and development of therapeutics targeted at the proliferative phase of infantile hemangiomas, reducing the subsequent postinvolutional scarring or deformities sometimes associated with these lesions.
authors.affiliation: Department of Pathology, Yale University School of Medicine, New Haven, CT, USA.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Tsuneki
authors.affiliation: Department of Pathology, Yale University School of Medicine, New Haven, CT, USA.
authors.forename: Steven
authors.initials: S
authors.lastname: Hardee
authors.affiliation: Department of Pathology, Yale University School of Medicine, New Haven, CT, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Michaud
authors.affiliation: Department of Pathology, Yale University School of Medicine, New Haven, CT, USA.
authors.forename: Raffaella
authors.initials: R
authors.lastname: Morotti
authors.affiliation: Department of Bioengineering, Case Western Reserve University, Cleveland, OH, USA.
authors.forename: Erin
authors.initials: E
authors.lastname: Lavik
authors.affiliation: Department of Pathology, Yale University School of Medicine, New Haven, CT, USA.
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Madri
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism*; D000818:Animals; D018797:Cell Cycle Proteins; D002478:Cells, Cultured; D002648:Child; D002675:Child, Preschool; D004195:Disease Models, Animal; D042783:Endothelial Cells / Q000378:metabolism; D005260:Female; D006391:Hemangioma / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D007223:Infant; D051034:Inhibitor of Apoptosis Proteins / Q000378:metabolism*; D060588:LIM Domain Proteins / Q000378:metabolism*; D008264:Macrophages / Q000378:metabolism; D008297:Male; D008810:Mice, Inbred C57BL; D010750:Phosphoproteins / Q000378:metabolism*; D012097:Repressor Proteins / Q000378:metabolism*; D000077022:Survivin; D046888:Tissue Array Analysis; D054457:Tissue Scaffolds; D000091102:YAP-Signaling Proteins
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C117749:Birc5 protein, mouse; D018797:Cell Cycle Proteins; D051034:Inhibitor of Apoptosis Proteins; D060588:LIM Domain Proteins; D010750:Phosphoproteins; D012097:Repressor Proteins; D000077022:Survivin; D000091102:YAP-Signaling Proteins; C486223:Yap1 protein, mouse; C485607:ajuba protein, mouse; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate