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475 Estrogen receptors in brain tumors
163s
La Piti&SalpXri&e
Faculty of Medicine, Paris, France.
In recent years, binding sites for all 5 classes of steroid receptors were detected in meningicxnas,i.e. mostly benign tmors arising from leptcmeninges.The characterization of binding systems was done with specific radioligands in presence of crqeting ste roids. It shawed that the affinity and specificity of Progestin, Androgen and rJluco_ corticoid binding sites were similar to those found in known target tissues. In addition, the Prgestin Receptor, i.e. (3H)R5020binding sites, was detected at high levels in well differentiated tumors whereas it was not in anaplastic cases. These results may suggest that : 1. Steroid Receptors play a role in tumor metabolism ; 2. the nmr of (PR) binding sites is linked to cellular differentiation ; 3. lepto meninges contain Steroid Receptors. Though, many problems remain to be solved : spe;i ficity of the Cstrcgen binding sites detected in some cases ; intracellular distribution of binding sites ; localization of target cells ; finally, biological effects of the Receptors. In conclusion, it can be hypothesized that the meningioma are a target tissue for steroids and that endocrine therapy may be relevant to unoperable and/or recurrent tuners.
475
ESTROGEN
RECEPTORS
IN BRAIN TUMORS
M.Fujimoto, E.Yoshino, S.Ueda, K.Hirakawa, J.Fujimoto, T.Tamaya Departmeni;of Neurosurgery, Obstetrics and Gynecology Kyoto Prefectural University of Medicine, Kyoto, Japan Hormone dependency of the brain tumor has long been suggested from the evidence that neurological symptoms deteriorate during pregnancy but the patient's condition improves after delivery. We estimated the cytosolic estrogen receptor in the brain tumor tissue of 66 patients with 32 meningiomas, 17 gliomas, 6 pituitary adenomas, 6 neurinomas and 5 metastatic brain tumors. Furthermore, nuclear estrogen receptors were examined in 11 meningiomas and 2 glioblastomas. Estrogen receptors , sre determined by the dextran coated charcoal method and analyzed by Scatchard plots. Cytosolic estrogen receptors were detected in 100% of the pituitary adenomas, 56% of meningiomas, 40% of metastatic brain tumors and 17% of neurinomas as well as in 5% of gliomas which were all medulloblastomas. On the other hand, nuclear estrogen receptors were found in preBenopausa1 females with meningioma. All dissociation constants were smaller than 10 M. Our findings indicate that some brain tumors are responsive to estrogen via the cellular estrogen receptor.
4i
PROGESTIN AND OESTROGEN RECEPTORS IN HUMAN MENINGIOMA - AN UPDATE M.A. Blankenstein, G. Blaauw' & S.W.J. LambertsO. Department of Biochemistry, Rotterdam Radio-Therapeutic Institute and Departments of 'Neurosurgery and "Internal Medicine III Erasmus University Rotterdam, Rotterdam, The Netherlands. We recently reported on the presence of progestin receptors (PR) in the absence of oestrogen receptors (ER) in meningioma tissue (Eur J Cancer Clin Oncol 19, 1983, 365). At present, our series consists of 33 tumours from 24 female and 8 male patients. PR were detected by DCC assay and Scatchard Plot analysis in 30/33 tumours. The mean PR content of PR positive tumours was 288f103 fmol/mg protein (s.e.m.). The Ed was l.lf0.2 nmol/l, which is in agreement with that found in human breast cancer (O.StO.03; n=500). In 3 meningiomas an ER was detected although the concentration was very low (13, 15 and 42 fmol/mg protein) and the Ed was rather high (3.5; 2.2 and 1.1 nmol/l respectively), as compared to the ER in human breast cancer (0.45tO.03 nmol/l; n=500). The ER in these meningiomas could also be detected by iso-electric focussing, but the ER levels detected by this method were even lower (1; 2 and 7 fmol/mg protein respectively). The IEP of the ER in meningioma (6.4 f 0.2) was equal to that in human breast cancer (6.4 f 0.1; n=21). Five non-meningioma tumours were studied, 3 fibrosarcomas and 2 neurinomas. No ER was detected, and in only one neurinoma PR occurred at a low level (14 fmol/mg protein). The occurrence of PR thus seems to be specific for meningiomas. A physiological role for PR in this tissue remains to be elucidated, especially since the majority of samples lacks detectable amounts of oestrogen receptors.
La Piti&SalpXri&e
Faculty of Medicine, Paris, France.
In recent years, binding sites for all 5 classes of steroid receptors were detected in meningicxnas,i.e. mostly benign tmors arising from leptcmeninges.The characterization of binding systems was done with specific radioligands in presence of crqeting ste roids. It shawed that the affinity and specificity of Progestin, Androgen and rJluco_ corticoid binding sites were similar to those found in known target tissues. In addition, the Prgestin Receptor, i.e. (3H)R5020binding sites, was detected at high levels in well differentiated tumors whereas it was not in anaplastic cases. These results may suggest that : 1. Steroid Receptors play a role in tumor metabolism ; 2. the nmr of (PR) binding sites is linked to cellular differentiation ; 3. lepto meninges contain Steroid Receptors. Though, many problems remain to be solved : spe;i ficity of the Cstrcgen binding sites detected in some cases ; intracellular distribution of binding sites ; localization of target cells ; finally, biological effects of the Receptors. In conclusion, it can be hypothesized that the meningioma are a target tissue for steroids and that endocrine therapy may be relevant to unoperable and/or recurrent tuners.
475
ESTROGEN
RECEPTORS
IN BRAIN TUMORS
M.Fujimoto, E.Yoshino, S.Ueda, K.Hirakawa, J.Fujimoto, T.Tamaya Departmeni;of Neurosurgery, Obstetrics and Gynecology Kyoto Prefectural University of Medicine, Kyoto, Japan Hormone dependency of the brain tumor has long been suggested from the evidence that neurological symptoms deteriorate during pregnancy but the patient's condition improves after delivery. We estimated the cytosolic estrogen receptor in the brain tumor tissue of 66 patients with 32 meningiomas, 17 gliomas, 6 pituitary adenomas, 6 neurinomas and 5 metastatic brain tumors. Furthermore, nuclear estrogen receptors were examined in 11 meningiomas and 2 glioblastomas. Estrogen receptors , sre determined by the dextran coated charcoal method and analyzed by Scatchard plots. Cytosolic estrogen receptors were detected in 100% of the pituitary adenomas, 56% of meningiomas, 40% of metastatic brain tumors and 17% of neurinomas as well as in 5% of gliomas which were all medulloblastomas. On the other hand, nuclear estrogen receptors were found in preBenopausa1 females with meningioma. All dissociation constants were smaller than 10 M. Our findings indicate that some brain tumors are responsive to estrogen via the cellular estrogen receptor.
4i
PROGESTIN AND OESTROGEN RECEPTORS IN HUMAN MENINGIOMA - AN UPDATE M.A. Blankenstein, G. Blaauw' & S.W.J. LambertsO. Department of Biochemistry, Rotterdam Radio-Therapeutic Institute and Departments of 'Neurosurgery and "Internal Medicine III Erasmus University Rotterdam, Rotterdam, The Netherlands. We recently reported on the presence of progestin receptors (PR) in the absence of oestrogen receptors (ER) in meningioma tissue (Eur J Cancer Clin Oncol 19, 1983, 365). At present, our series consists of 33 tumours from 24 female and 8 male patients. PR were detected by DCC assay and Scatchard Plot analysis in 30/33 tumours. The mean PR content of PR positive tumours was 288f103 fmol/mg protein (s.e.m.). The Ed was l.lf0.2 nmol/l, which is in agreement with that found in human breast cancer (O.StO.03; n=500). In 3 meningiomas an ER was detected although the concentration was very low (13, 15 and 42 fmol/mg protein) and the Ed was rather high (3.5; 2.2 and 1.1 nmol/l respectively), as compared to the ER in human breast cancer (0.45tO.03 nmol/l; n=500). The ER in these meningiomas could also be detected by iso-electric focussing, but the ER levels detected by this method were even lower (1; 2 and 7 fmol/mg protein respectively). The IEP of the ER in meningioma (6.4 f 0.2) was equal to that in human breast cancer (6.4 f 0.1; n=21). Five non-meningioma tumours were studied, 3 fibrosarcomas and 2 neurinomas. No ER was detected, and in only one neurinoma PR occurred at a low level (14 fmol/mg protein). The occurrence of PR thus seems to be specific for meningiomas. A physiological role for PR in this tissue remains to be elucidated, especially since the majority of samples lacks detectable amounts of oestrogen receptors.