title: Immunohistochemical detection of progesterone and cellular proliferation in canine mammary tumours.
abstract: Immunohistochemical expression of progesterone and the cellular proliferation marker Ki-67 was assessed in formalin-fixed, paraffin wax-embedded samples from 43 canine mammary tumours. Benign tumours showed high surface membrane progesterone expression (mean 196.42+/-25.91 positively labelled cells per 500 tumour cells) and low cellular proliferation (52.14+/-16.73 positively labelled cells per 500 tumour cells), whilst malignant tumours had low progesterone expression (68.19+/-17.53 positively labelled cells per 500 tumour cells) and higher cellular proliferation (141.72+/-23.65 positively labelled cells per 500 tumour cells), the difference being statistically significant (P<0.005) in both cases. These findings suggest that the majority of progesterone receptors in canine mammary tumour tissue are not associated with bound progesterone. The progression towards malignancy in spontaneously arising canine mammary tumours therefore appears to be associated with a decrease in steroid hormone dependency. Progesterone expression was also noted in the cytoplasm of tumour cells where it may be associated with a cellular repair mechanism. This hypothesis is supported by the finding of significantly higher progesterone content in the cytoplasm of benign tumour cells.
authors.affiliation: Department of Obstetrics and Reproduction, Faculty of Veterinary Science, Szent István University, P.O. Box 2, H-1400 Budapest, Hungary. thuroczy.julianna@aotk.szie.hu
authors.forename: J
authors.initials: J
authors.lastname: Thuróczy
authors.forename: G J K
authors.initials: GJ
authors.lastname: Reisvaag
authors.forename: E
authors.initials: E
authors.lastname: Perge
authors.forename: A
authors.initials: A
authors.lastname: Tibold
authors.forename: J
authors.initials: J
authors.lastname: Szilágyi
authors.forename: L
authors.initials: L
authors.lastname: Balogh
mesh_terms: D000236:Adenoma / Q000378:metabolism / Q000473:pathology; D000818:Animals; D002296:Carcinosarcoma / Q000378:metabolism / Q000473:pathology; D002467:Cell Nucleus / Q000378:metabolism / Q000473:pathology; D049109:Cell Proliferation; D003593:Cytoplasm / Q000378:metabolism / Q000473:pathology; D018450:Disease Progression; D004283:Dog Diseases / Q000378:metabolism* / Q000473:pathology*; D004285:Dogs; D005260:Female; D018226:Fibroadenoma / Q000378:metabolism / Q000473:pathology; D019394:Ki-67 Antigen / Q000378:metabolism; D015674:Mammary Neoplasms, Animal / Q000378:metabolism* / Q000473:pathology*; D011374:Progesterone / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000378:metabolism
chemical_list: D019394:Ki-67 Antigen; D011980:Receptors, Progesterone; D011374:Progesterone