title: Pericyte antigens in angiomyolipoma and PEComa family tumors.
abstract: Perivascular epithelioid cell tumors (PEComas) are an uncommon family of soft tissue tumors with dual myoid-melanocytic differentiation. Although PEComa family tumors commonly demonstrate a perivascular growth pattern, pericyte antigen expression has not yet been examined among this unique tumor group. Previously, we demonstrated that a subset of perivascular soft tissue tumors exhibit a striking pericytic immunophenotype, with diffuse expression of αSMA, CD146, and PDGFRβ. Here, we describe the presence of pericyte antigens across a diverse group of PEComa family tumors (n = 19 specimens). Results showed that pericyte antigens differed extensively by histological appearance. Typical angiomyolipoma (AML) specimens showed variable expression of pericyte antigens among both perivascular and myoid-appearing cells. In contrast, AML specimens with a predominant spindled morphology showed diffuse expression of pericyte markers, including αSMA, CD146, and PDGFRβ. AML samples with predominant epithelioid morphology showed a marked reduction in or the absence of immunoreactivity for pericyte markers. Lymphangiomyoma samples showed more variable and partial pericyte marker expression. In summary, pericyte antigen expression is variable among PEComa family tumors and largely varies by tumor morphology. Pericytic marker expression in PEComa may represent a true pericytic cell of origin, or alternatively aberrant pericyte marker adoption. Markers of pericytic differentiation may be of future diagnostic utility for the evaluation of mesenchymal tumors, or identify actionable signaling pathways for future therapeutic intervention.
authors.affiliation: Division of Growth and Development, School of Dentistry, University of California, Los Angeles, CA, USA.
authors.forename: Jia
authors.initials: J
authors.lastname: Shen
authors.forename: Swati
authors.initials: S
authors.lastname: Shrestha
authors.forename: Yu-Hsin
authors.initials: YH
authors.lastname: Yen
authors.forename: Michelle A
authors.initials: MA
authors.lastname: Scott
authors.forename: Greg
authors.initials: G
authors.lastname: Asatrian
authors.forename: Raymond
authors.initials: R
authors.lastname: Barnhill
authors.forename: Claire
authors.initials: C
authors.lastname: Lugassy
authors.forename: Chia
authors.initials: C
authors.lastname: Soo
authors.forename: Kang
authors.initials: K
authors.lastname: Ting
authors.forename: Bruno
authors.initials: B
authors.lastname: Peault
authors.forename: Sarah M
authors.initials: SM
authors.lastname: Dry
authors.forename: Aaron W
authors.initials: AW
authors.lastname: James
mesh_terms: D000199:Actins / Q000032:analysis / Q000378:metabolism; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018207:Angiomyolipoma / Q000276:immunology / Q000473:pathology*; D000951:Antigens, Neoplasm / Q000032:analysis* / Q000378:metabolism; D014408:Biomarkers, Tumor / Q000032:analysis; D051929:CD146 Antigen / Q000032:analysis / Q000378:metabolism; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D020286:Pericytes / Q000276:immunology / Q000473:pathology*; D054973:Perivascular Epithelioid Cell Neoplasms / Q000276:immunology / Q000473:pathology*; D020797:Receptor, Platelet-Derived Growth Factor beta / Q000032:analysis / Q000378:metabolism
chemical_list: C541116:ACTA2 protein, human; D000199:Actins; D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D051929:CD146 Antigen; C497902:MCAM protein, human; D020797:Receptor, Platelet-Derived Growth Factor beta