title: Overexpression of p53 in the endometrial gland in postmenopausal women.
abstract: OBJECTIVE
  The p53 signature, which (although morphologically unremarkable) displays diffuse and strong p53 nuclear staining, has been proposed to be a precursor of serous endometrial intraepithelial carcinoma. We examined the overexpression of p53 in postmenopausal endometrial glands.
  
  
  METHODS
  Postmenopausal endometrial tissues of 82 women with benign disease, including 10 hormone users, were evaluated in this study. Tissues with endometrial hyperplasia and/or polyps were excluded based on a histopathologic review. Expressions of estrogen receptor-α, Ki-67, and p53 were immunohistochemically examined. Apoptotic cells were identified using a terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Overexpression of p53 was categorized as moderate to strong in more than 50% of glandular cell nuclei.
  
  
  RESULTS
  Focal glandular overexpression of p53 was observed in 1 (9%) of 10 and in 8 (11%) of 72 postmenopausal endometrial tissue specimens in women with and women without a history of hormone use, respectively. Among nonhormone users, the median Ki-67 and apoptotic indices in the postmenopausal endometrial glands of women with and women without overexpression of p53 were 16% and 6% (P = 0.007) and 1% and 1% (P = 0.345), respectively. All postmenopausal endometrial glands were positive for estrogen receptor-α, regardless of the overexpression of p53. The postmenopausal endometrial glands of estrogen users exhibited significantly higher Ki-67 and apoptotic indices than those of nonestrogen users (P = 0.001 and P < 0.001, respectively).
  
  
  CONCLUSIONS
  Overexpression of p53 may be responsible for the high proliferative activity of postmenopausal endometrial glandular cells associated with conditions of low apoptotic cell death.
authors.affiliation: From the Departments of 1Obstetrics and Gynecology, 2Pathology and Cell Biology, and 3Preventive Medicine and Community Health, School of Medicine, University of Occupational and Environmental Health, Iseigaoka, Yahatanishi-ku, Kitakyushu, Japan.
authors.forename: Chiho
authors.initials: C
authors.lastname: Koi
authors.forename: Toru
authors.initials: T
authors.lastname: Hachisuga
authors.forename: Midori
authors.initials: M
authors.lastname: Murakami
authors.forename: Tomoko
authors.initials: T
authors.lastname: Kurita
authors.forename: Thuy Thi
authors.initials: TT
authors.lastname: Nguyen
authors.forename: Shohei
authors.initials: S
authors.lastname: Shimajiri
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Fujino
mesh_terms: D017209:Apoptosis; D004717:Endometrium / Q000378:metabolism* / Q000473:pathology; D047628:Estrogen Receptor alpha / Q000032:analysis; D015914:Estrogen Replacement Therapy; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D019394:Ki-67 Antigen / Q000032:analysis; D008875:Middle Aged; D017698:Postmenopause / Q000378:metabolism*; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*
chemical_list: D047628:Estrogen Receptor alpha; D019394:Ki-67 Antigen; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53