title: Expression of Yes-associated protein (YAP) in breast phyllodes tumor.
abstract: This study aimed to identify expression profiles of Yes-associated protein (YAP) and its phosphorylated form (pYAP) in phyllodes tumor (PT) of human breast and verify the clinical implications. We selected PTs from the pathologic archive and reviewed the histologic features (141 benign, 27 borderline, and 15 malignant). We made tissue microarray (TMA) block from the formalin-fixed paraffin-embedded (FFPE) tissue corresponding to the representative section. Using TMA block, we performed immunohistochemical staining of YAP and pYAP. In the stromal component, expressions of YAP and pYAP were increased in borderline/malignant PT with comparison of benign PT (P = 0.002, and P < 0.001, respectively). In the epithelial component, cytoplasmic expression of YAP was highest in borderline PT (P = 0.001). Stromal YAP expression (P < 0.001) and stromal pYAP expression (P = 0.042) were associated with shorter disease-free survival (DFS) and stromal pYAP expression (P = 0.001) was associated with shorter overall survival (OS) in univariate Cox analysis. In multivariate Cox analysis, stromal YAP expression was an independent prognostic factor associated with shorter DFS (Hazard ration: 3.206, 95% CI: 1.000-10.27, P = 0.050). In conclusion, expression level of YAP in stromal component was increased along with histologic grade of PT and YAP expression in PT was related to tumor progression and poor prognosis.
authors.affiliation: Department of Pathology, Yonsei University College of Medicine Seoul, South Korea.
authors.forename: Sang Kyum
authors.initials: SK
authors.lastname: Kim
authors.affiliation: Department of Pathology, Yonsei University College of Medicine Seoul, South Korea.
authors.forename: Woo Hee
authors.initials: WH
authors.lastname: Jung
authors.affiliation: Department of Pathology, Yonsei University College of Medicine Seoul, South Korea.
authors.forename: Ja Seung
authors.initials: JS
authors.lastname: Koo
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000032:analysis*; D000328:Adult; D014408:Biomarkers, Tumor / Q000032:analysis; D001943:Breast Neoplasms / Q000737:chemistry* / Q000401:mortality / Q000473:pathology / Q000628:therapy; D018450:Disease Progression; D018572:Disease-Free Survival; D004847:Epithelial Cells / Q000737:chemistry; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D053208:Kaplan-Meier Estimate; D008875:Middle Aged; D015999:Multivariate Analysis; D060787:Neoplasm Grading; D010750:Phosphoproteins / Q000032:analysis*; D010766:Phosphorylation; D003557:Phyllodes Tumor / Q000737:chemistry* / Q000401:mortality / Q000473:pathology / Q000628:therapy; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D017154:Stromal Cells / Q000737:chemistry; D013997:Time Factors; D046888:Tissue Array Analysis; D014157:Transcription Factors; D000091102:YAP-Signaling Proteins
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D014408:Biomarkers, Tumor; D010750:Phosphoproteins; D014157:Transcription Factors; D000091102:YAP-Signaling Proteins; C088374:YAP1 protein, human
keywords: Breast; YAP; phyllodes tumor