CHARACTERIZATION OF BINDING-SITES FOR A GNRH-AGONIST (BUSERELIN) IN HUMAN BREAST-CANCER BIOPSIES AND THEIR DISTRIBUTION IN RELATION TO TUMOR PARAMETERS

Gonadotropin-releasing hormone analogs (GnRH-A) have been added to the armentarium in the therapy of hormone-dependent breast cancer in prem enopausal women. The effect of chronic GnRH-A-treatment in premenopaus al women is based on the suppression of the hypothalamus-pituitary-ova rian axis and the reduction of sex-steroid serum levels. In addition, a number of experimental and clinical data have been accumulated indic ating a direct action of GnRH-A on breast cancer cells and tissue. In this study we analyzed 235 human breast cancer biopsies for specific G nRH-A-binding. We demonstrate high affinity GnRH-A binding sites in hu man breast cancer tissues. The evaluation of clinical data showed no c orrelation of the level of GnRH-A-binding with classical tumor paramet ers.