title: Use of serial semithin frozen sections to evaluate the co-localization of estrogen receptors and progesterone receptors in cells of breast cancer tissues.
abstract: The extent of co-expression of estrogen receptors (ER) and progesterone receptors (PgR) in breast cancer cells was examined immunocytochemically. Eight surgical cases of infiltrating ductal carcinoma designated as ER-positive and PgR-positive (ER+/PgR+) by enzyme immunoassay (EIA) were used. They were fixed with 4% formaldehyde and cut into serial frozen semithin sections. Using sections stained with either anti-ER or anti-PgR antibody, we ascertained the co-localization of ER and PgR in a single cell and estimated the ratio of the number of cells co-expressing ER and PgR. Twenty-six to 95% of the cells were immunopositive for both ER and PgR, 2-25% of them, varying in cases, were positive for ER but not for PgR, and <3% of the cells were positive for PgR but not for ER. The remaining 5-60% cells were positive for neither ER nor PgR. A significant percentage of breast cancer cells in tissues designated as ER+/PgR+ by EIA showed the phenotype of ER-positive but PgR-negative. The co-expression ratio of ER and PgR in biochemically detected ER+/PgR+ breast cancer may reflect a particular clinical parameter, such as the heterogeneous responsiveness of ER+/PgR+ breast cancers to hormonal treatment. Immunostaining of serial semithin frozen sections for two or more different antigens is a useful method to assess the correlation of localization of antigens.
authors.affiliation: Department of Anatomy, Kyorin University School of Medicine, Tokyo, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Kudo
authors.forename: H
authors.initials: H
authors.lastname: Fukushima
authors.forename: H
authors.initials: H
authors.lastname: Kawakami
authors.forename: M
authors.initials: M
authors.lastname: Matsuda
authors.forename: T
authors.initials: T
authors.lastname: Goya
authors.forename: H
authors.initials: H
authors.lastname: Hirano
mesh_terms: D000818:Animals; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000648:ultrastructure; D018270:Carcinoma, Ductal, Breast / Q000378:metabolism* / Q000473:pathology / Q000648:ultrastructure; D005260:Female; D005629:Frozen Sections; D006801:Humans; D051381:Rats; D011960:Receptors, Estrogen / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000378:metabolism*
chemical_list: D011960:Receptors, Estrogen; D011980:Receptors, Progesterone