Steroid receptors in malignant skeletal tumors

As an initial step in investigating the role of steroid hormones in skeletal tumors, the incidence of cytosol receptors for steroid hormones was determined. Four osteosarcoma (two primary, two metastatic), two chondrosarcomas, one Ewing's sarcoma, and one malignant giant cell tumor were assayed for receptor. Six of eight tumors (75%) had receptors for at least one steroid, and four of eight (50%) tumors had more than one receptor. Receptor for glucocorticoid was found in four of seven tumors cytosols (57%). Receptor for androgen and progesterone was present in three of seven cytosols (43%), while estrogen bound to two of eight (25%). Characterization of steroid binding in a subset of skeletal tumors revealed specific, high affinity, saturable receptors for all steroid classes with Kd's similar to those found in other tumors. These data suggest a rationale for a prospective, randomized, double blind study of endocrine therapy in advanced metastatic disease of primary bone sarcomas.