Hormonal prevention of breast cancer: Mimicking the protective effect of pregnancy
- 2 March 1999
- journal article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 96 (5) , 2520-2525
- https://doi.org/10.1073/pnas.96.5.2520
Abstract
Full term pregnancy early in life is the most effective natural protection against breast cancer in women. Rats treated with chemical carcinogen are similarly protected by a previous pregnancy from mammary carcinogenesis. Proliferation and differentiation of the mammary gland does not explain this phenomenon, as shown by the relative ineffectiveness of perphenazine, a potent mitogenic and differentiating agent. Here, we show that short term treatment of nulliparous rats with pregnancy levels of estradiol 17β and progesterone has high efficacy in protecting them from chemical carcinogen induced mammary cancers. Because the mammary gland is exposed to the highest physiological concentrations of estradiol and progesterone during full term pregnancy, it is these elevated levels of hormones that likely induce protection from mammary cancer. Thus, it appears possible to mimic the protective effects of pregnancy against breast cancer in nulliparous rats by short term specific hormonal intervention.Keywords
This publication has 21 references indexed in Scilit:
- Functional role of estrogen metabolism in target cells: review and perspectivesCarcinogenesis: Integrative Cancer Research, 1998
- Chorionic gonadotropin inhibits rat mammary carcinogenesis through activation of programmed cell deathCarcinogenesis: Integrative Cancer Research, 1997
- Mammary gland neoplasia in long-term rodent studies.Environmental Health Perspectives, 1996
- Refractoriness to mammary tumorigenesis in parous rats: is it caused by persistent changes in the hormonal environment or permanent biochemical alterations in the mammary epithelia?Carcinogenesis: Integrative Cancer Research, 1995
- Follow-up Studies of Breast Cancer Incidence among Atomic Bomb SurvivorsJournal of Radiation Research, 1991
- Mortality from Breast Cancer after Irradiation during Fluoroscopic Examinations in Patients Being Treated for TuberculosisNew England Journal of Medicine, 1989
- The Risk of Breast Cancer after Irradiation of the Thymus in InfancyNew England Journal of Medicine, 1989
- Laboratory studies to develop general principles for the adjuvant treatment of breast cancer with antiestrogens: Problems and potential for future clinical applicationsBreast Cancer Research and Treatment, 1983
- Effect of ovarian hormones on the induction of 1-methyl-1-nitrosourea-induced mammary cancerCarcinogenesis: Integrative Cancer Research, 1983
- Effect of increasing doses of estrogen and progesterone on mammary carcinogenesis in the ratPublished by Elsevier ,1973