Tamoxifen has no effect on p27 protein expression in endometrium

(January 19, 2004)

"The cyclin-dependent kinase inhibitor, p27, has been shown to mediate cell growth arrest thereby significantly reducing the percentage of proliferating cells. It seems that p27 expression is essential for the control of normal endometrial proliferation, and reduced or absent p27 expression may be an important step in endometrial carcinogenesis. Our aim was to demonstrate the effects of tamoxifen therapy on the expression of p27 protein in the endometrium of postmenopausal breast cancer patients," scientists in Brazil report.

"Fifty-three pre-and post-tamoxifen treatment endometrium samples were examined immunohistochemically using p27 antibody," said A. A. Siufi and colleagues at the Federal University of Mato Grosso in Sao Paulo. "Tamoxifen therapy (20 mg/day) for 60 days increased the expression of p27 protein in the endometrium of postmenopausal breast cancer patients. We conclude that tamoxifen therapy does not seem to be directly involved in the carcinogenesis of endometrial carcinoma since the expression of p27 is not decreased."

Siufi and associates published their study in the International Journal of Oncology (Effects of tamoxifen therapy on the expression of p27 protein in the endometrium of women with primary breast cancer. Int J Oncol, 2003;23(6):1545-1551).

For additional information, contact W. J. Goncalves, Department of Gynecology and Obstetrics of the Escola Paulista de Medicina, Universidade Federal de Sao Paulo, Rua Botucatu 572, Suite 102, BR-04023061 Sao Paulo, SP, Brazil.

The publisher's contact information for the International Journal of Oncology is: Professor DA Spandidos, 1, S Merkouri Street, Editorial Office,, Athens 116 35, Greece.