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Updated: Oct 3, 2026

An Ex vivo Model to Study Hormone Action in the Human Breast
Published on: January 8, 2015
Hormone-related factors associated with hormone receptor levels in breast cancer
L Calzada1, J M Martinez, T Sandoval
1Unidad de Investigación Médica en Biología Reproductiva, Subjefatura de Investigación Biomédica, Instituto Mexicano del Seguro Social, México D.F., México. leo_calzada@yahoo.com
Abstract:
Estrogen receptor (ER) and progesterone receptor (PgR) levels were determined in patients with a ductal infiltrating breast carcinoma. In premenopausal patients, the distribution of the PgR was higher than that of the ER. With increasing age of the patients, the concentration of the ER increased, whereas the PgR values showed an inverse relationship. According to the menstrual status, ER and PgR values were found to be higher in postmenopausal patients than in premenopausal ones. In relation to body fat distribution, in premenopausal patients the ER or PgR values were not found to be statistically significantly different (data no shown). In postmenopausal patients, the concentration of ER was diminished by 20% in patients with obesity of the upper body segment and by 40% in patients with obesity of the lower body segment as compared with the ER values of nonobese patients. While the PgR values diminished by 20% in patients with obesity of the lower body segment, in relation to PgR values of patients with obesity of the upper body segment, we found no statistically significant differences when compared with the PgR values of nonobese patients. With regard to the body mass index, this has remained constant in both types of body fat distribution. When body mass index values were compared with serum ER and PgR levels, no statistically significant differences were found.
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