title: Apoptosis and the expression of Bcl-2 and Bax in patients with endometrioid, clear cell, and serous carcinomas of the uterine endometrium.
abstract: OBJECTIVE
  Clear cell and serous carcinoma of the uterus are rare types of endometrial carcinomas. This study was designed to investigate the differential occurrence of apoptosis, Bcl-2, and Bax in endometrioid, clear cell, and serous carcinomas.
  
  
  METHODS
  In a total of 28 endometrial carcinomas as well as 4 samples of normal postmenopausal endometria, apoptotic changes were examined using molecular biochemical techniques. The expression of Bcl-2 and Bax proteins was also investigated by immunohistochemical staining with appropriate antibodies.
  
  
  RESULTS
  Labeling of DNA in situ indicated that apoptotic cells were sporadically seen in postmenopausal endometrium (5.2 +/- 2.1, n = 4). In contrast, cells undergoing apoptosis apparently were detected in endometrioid carcinoma (29.3 +/- 3.7, n = 20), and their numbers increased intensely in clear cell (49.5 +/- 5.6, n = 5) and serous carcinomas (50.8 +/- 6.0, n = 3). Autoradiographic analysis revealed that high-molecular-weight DNA was predominant in postmenopausal endometrium. However, a DNA ladder was identified in 7 of 10 carcinomas. Although Bcl-2 was immunonegative or faintly immunopositive in all cases, many cases of endometrioid carcinoma (43.6 +/- 4.1%, n = 20) were immunopositive for Bax, unlike postmenopausal endometrium (17.6 +/- 6.7%, n = 4). Moreover, the number of cells expressing Bax increased in clear cell (60.4 +/- 6.5%, n = 5) and serous carcinomas (66.8 +/- 7.6%, n = 3) compared with that in endometrioid carcinoma.
  
  
  CONCLUSIONS
  These results indicate that apoptosis occurs in a specific population of cells in different histologic components of endometrial carcinomas. The expression of Bax, but not of Bcl-2, might suggest histologic differentiation in endometrial carcinomas.
authors.affiliation: Department of Obstetrics and Gynecology, Wakayama Medical College, 811-1 Kimidera, Wakayama 641-0012, Japan. katsu@wakayama-med.ac.jp
authors.forename: K
authors.initials: K
authors.lastname: Kokawa
authors.forename: T
authors.initials: T
authors.lastname: Shikone
authors.forename: T
authors.initials: T
authors.lastname: Otani
authors.forename: R
authors.initials: R
authors.lastname: Nishiyama
authors.forename: Y
authors.initials: Y
authors.lastname: Ishii
authors.forename: S
authors.initials: S
authors.lastname: Yagi
authors.forename: M
authors.initials: M
authors.lastname: Yamoto
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism* / Q000473:pathology*; D018262:Adenocarcinoma, Clear Cell / Q000378:metabolism / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017209:Apoptosis / Q000502:physiology*; D018269:Carcinoma, Endometrioid / Q000378:metabolism / Q000473:pathology; D018284:Cystadenocarcinoma, Serous / Q000378:metabolism / Q000473:pathology; D053938:DNA Fragmentation; D016889:Endometrial Neoplasms / Q000378:metabolism* / Q000473:pathology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis*; D051028:bcl-2-Associated X Protein
chemical_list: C494826:BAX protein, human; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein