title: Paradoxical expression of cell cycle inhibitor p27 in endometrioid adenocarcinoma of the uterine corpus - correlation with proliferation and clinicopathological parameters.
abstract: p27 is regarded as a cyclin-dependent kinase inhibitor of the G1-to-S cell cycle progression by suppressing the kinase activity of cyclin/cyclin-dependent kinase complex. This study aimed to investigate p27 expression in the normal endometrium and endometrioid adenocarcinoma of the uterine corpus and the correlation of its expression with cell proliferation and clinicopathological parameters. Tissue samples of 127 endometrioid adenocarcinomas and 15 normal endometria were used in the study. Immunohistochemical staining for detecting p27 and Ki-67 was performed by the labelled streptavidin-biotin method on formalin-fixed and paraffin-embedded tissue samples. The expression was given as the labelling index, which indicates the percentage of positive nuclei. p27 staining was observed in the nuclei of the glandular cells in the functional layer of the secretory phase endometrium, whereas it was negative in those of the proliferative phase. In endometrioid adenocarcinomas, the labelling index of p27 expression paradoxically increased more significantly in the higher histological grades and was correlated with that of Ki-67. The high level of p27 expression was associated with clinicopathological parameters such as FIGO stage, lymph node metastasis, lymphovascular space involvement and myometrial invasion. High p27 expression was linked to higher grades of endometrioid adenocarcinoma, cell proliferation and some clinical prognostic factors. These results indicate that p27 might be an indicator of poor prognosis.
authors.affiliation: Department of Pathology, Kitasato University School of Medicine, 1-15-1, Kitasato, Sagamihara, Kanagawa, 228-8555, Japan. watajun@med.kitasato-u.ac.jp
authors.forename: J
authors.initials: J
authors.lastname: Watanabe
authors.forename: H
authors.initials: H
authors.lastname: Sato
authors.forename: T
authors.initials: T
authors.lastname: Kanai
authors.forename: Y
authors.initials: Y
authors.lastname: Kamata
authors.forename: T
authors.initials: T
authors.lastname: Jobo
authors.forename: H
authors.initials: H
authors.lastname: Hata
authors.forename: T
authors.initials: T
authors.lastname: Fujisawa
authors.forename: E
authors.initials: E
authors.lastname: Ohno
authors.forename: T
authors.initials: T
authors.lastname: Kameya
authors.forename: H
authors.initials: H
authors.lastname: Kuramoto
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018797:Cell Cycle Proteins / Q000096:biosynthesis*; D002455:Cell Division; D002467:Cell Nucleus; D050760:Cyclin-Dependent Kinase Inhibitor p27; D016889:Endometrial Neoplasms / Q000235:genetics* / Q000473:pathology; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D025521:Tumor Suppressor Proteins / Q000096:biosynthesis*
chemical_list: D018797:Cell Cycle Proteins; D025521:Tumor Suppressor Proteins; D050760:Cyclin-Dependent Kinase Inhibitor p27