Estrogen stimulates breast cancer

Tonetti, D. A., and Jordan, V. C. 1997. The role of estrogen receptor mutations in tamoxifen-stimulated breast cancer (review). J. SteroidBiochem. Mol. Biol. 62 119-128. 

Schafer, J.M., Lee, E.S., Dardes, R.C., Bentrem, D., O Regan, R.M., De Los Reyes, A. and Jordan, V.C. (2001) Analysis of cross-resistance of the selective estrogen receptor modulators arzoxifene (LY353381) and LY117018 in tamoxifen-stimulated breast cancer xenografts. Clinical Cancer Research, 7, 2505-2512. 

Allred, C.D., Ju, Y.H., Alfred, K.F., Chang, J., and Helferich, W.G., Dietary genistin stimulates growth of estrogen-dependent breast cancer tumors similar to that observed with genistein. Carcinogenesis, 22,1667, 2001. 

Droloxifene (3-hydroxy-tamoxifen) behaves as an estrogen agonist in bone tissue and several lipid and coagulation markers in castrated rat models and does not show stimulation of the endometrial epithelium in preclinical studies (Ke et al. 1997). Endometrial stimulation has, however, been observed in clinical trials, which, together with the fact that as an estrogen agonist it is ten times less potent than tamoxifen in bone tissue and lipid metabolism (Hendrix et al. 2001) and that in a recent head-to-head comparison with tamoxifen droloxifene was demonstrated not to be superior in any parameter of breast cancer treatment efficacy (Buzdar et al. 2002), has resulted in cancellation of its clinical development. 

VI. Vignon, F., Capony, F., Chambon, M., Freiss, G., Garcia, M., and Rochefort, H., Autocrine growth stimulation on the MCF7 breast cancer cells by the estrogen-regulated 52K protein. Endocrinology 118, 1537-1545 (1986). 

Harnagea-Theophilus E. and M.R. Miller (1999). Acetaminophen alters estrogenic responses in vitro Stimulation of DNA synthesis in estrogen-responsive human breast cancer cells. Toxicological Sciences 46 38 14. 

Mechanism of Action Decreases the level of circulating estrogen by inhibiting aro-matase, an enzyme that catalyzes the final step in estrogen production. Therapeutic Effect Inhibits the growth of breast cancers that are stimulated by estrogens. 

Peterson TG, Barnes S. Genistein inhibits both estrogen and growth factor stimulated proliferation of human breast cancer cells. Cell Growth Differ. 1, 1345-1351, 1996. 

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