Estrogen and progesterone receptor subtype expression in normal and malignant ovarian epithelial cell cultures.

Abstract

Epidemiologic data suggest that the malignant transformation of ovarian epithelium may be linked to altered steroid hormone homeostasis. Estrogen receptor-alpha, estrogen receptor-beta, progesterone receptor A, and progesterone receptor B messenger RNA and protein expression were evaluated by reverse transcriptase-polymerase chain reaction and Western blot analysis in primary cell cultures of human ovarian surface epithelium (n = 23 cultures) and Cedars-Sinai ovarian cancer (n = 23 cultures). The ratio of estrogen receptor-alpha/estrogen receptor-beta messenger RNA expression was 10 times higher in primary ovarian cancer cultures (9.94 +/- 3.90) than in normal ovarian surface epithelium cultures (1.00 +/- 0.16, P =.04). Estrogen receptor-alpha/estrogen receptor-beta protein ratio in primary ovarian cancer cultures (2.13 +/- 0.43) was twice that of normal human ovarian surface epithelium cultures (1.00 +/- 0.13, P =.05). Individual estrogen receptor-alpha and estrogen receptor-beta messenger RNA and protein expression were not significantly different. Progesterone receptor B protein levels in primary ovarian cancer cultures (2.08 +/- 0.42) were twice that of normal surface ovarian epithelium cultures (1.00 +/- 0.10, P =.04), although differences in progesterone receptor B messenger RNA and progesterone receptor A protein expression were not observed. Malignant ovarian epithelial cells demonstrated multiple alterations in the expression of sex steroid hormone receptors.