Sex steroid receptor expression in 'carcinoid' tumours of the breast.

Nine 'carcinoids' of the breast (argyrophilic carcinomas) were examined for the presence of estrogen receptor (ER), progesterone receptor (PR), and androgen receptor (AR), using immunohistochemistry. The tumours were selected on the basis of their histo-morphological appearance and positive Grimelius stain. All cases were immunoreactive for neuron-specific enolase (NSE).

Immunohistochemical and prognostic analysis of apoptosis and proliferation in uveal melanoma.

Neoplasia can be defined as deregulated tissue homeostasis caused by an imbalance between proliferation and apoptosis. Many genes are involved in the maintenance of tissue homeostasis, eg, the c-myc oncoprotein, which is an important regulator of cell proliferation and Bcl-2 protein, which is involved in the regulation of apoptosis. We studied retrospectively indices of proliferation, such as mitotic count and the Mib-1 index, on 51 uveal melanomas and compared their prognostic significance with established indicators of prognosis such as cell type and tumor size.

Androgen receptor expression in the cervix of androgen-treated female-to-male transsexuals: association with morphology and chain-specific keratin expression.

Long-term androgen treatment of female-to-male transsexuals is associated with morphological changes of the ectocervical epithelium. This study was designed to correlate the histological changes of the ectocervix to modulation of androgen receptor (AR) and keratin expression. We evaluated AR expression by immunohistochemistry using monoclonal antibody F39.

An immunohistochemical evaluation of androgen and progesterone receptors in ovarian tumors.

To visualize the heterogeneity of androgen receptor (AR) and progesterone receptor (PR) expression in ovarian tumors, 61 specimens were studied immunohistochemically using specific mouse monoclonal antibodies. The tested ovarian tumors included ovarian carcinomas of serous, mucinous, endometrioid, undifferentiated, and clear cell types as well as borderline epithelial tumors, mucinous cystadenomas, granulosa cell tumors, metastatic ovarian tumors, and one case of immature teratoma. Sixty-seven percent of ovarian carcinomas expressed AR, while 46% of the ovarian carcinomas expressed PR.

Domains of the human androgen receptor involved in steroid binding, transcriptional activation, and subcellular localization.

A series of human androgen receptor (AR) deletion mutants was constructed to study the relationship between the structural domains and their different functions in the AR protein. Human AR mutants were expressed in COS-1 and HeLa cells to investigate hormone binding, transcriptional activation, and subcellular localization. The wild-type human AR (AR 1-910) was expressed as a 110- to 112-kDa doublet, as revealed on immunoblots.

Androgen receptors in endocrine-therapy-resistant human prostate cancer.

Despite the initial androgen-dependent growth of most human prostate cancers, eventually all prostate cancers become androgen-independent at varying intervals after androgen ablation or anti-androgen therapy. In order to gain more insight into the role of the androgen receptor (AR) in this process, AR and prostate-specific antigen (PA) expression was evaluated immunohistochemically in prostatic tumour tissues from patients who developed urinary flow obstruction between 4 and 107 months after onset of treatment. AR expression was evaluated with a monoclonal antibody (MAb) specific for the N-terminal domain of the human AR.

Ultrastructural and immunohistochemical segregation of gemistocytic subsets.

Gemistocytes are frequently encountered in cases of reactive gliosis as well as in glial tumors. Recently, miniature forms of gemistocytes (minigemistocytes) were recognized as cellular constituents of oligodendrogliomas. Antibodies specific for the intermediate filaments glial fibrillary acidic protein and vimentin are reactive with gemistocytic cells, but do not react specifically with these cells.

Uterine artery estrogen receptors in the nonpregnant and pregnant guinea pig.

Uterine artery, heart, and aorta or carotid specimens of nonpregnant, midpregnant, and term pregnant guinea pigs were examined for estrogen receptors by immunocytochemical methods. Estrogen receptors were found in the nuclei of cells in the endothelial, muscle, and adventitia layers of the uterine artery wall. The concentration of estrogen receptors was slightly higher in nonpregnant and term pregnant animals than in midpregnancy.

Feasibility of the immunohistochemical detection of endogenous steroids in paraffin-embedded ovarian tumours.

Formalin-fixed, paraffin-embedded samples from 25 ovarian granulosa cell tumours and six poorly differentiated ovarian carcinomas were examined immunohistochemically for the presence of estradiol, testosterone and progesterone. Twenty-four of the 25 granulosa cell tumours stained for estradiol predominantly in granulosa cells and also in the theca cells, but none of the carcinomas were positive. All the granulosa cell tumours and five out of six carcinomas were positive for progesterone, while 13 granulosa cell tumours and three carcinomas stained moderately positive for testosterone.

Heterogeneity of growth hormone (GH) release by individual pituitary adenoma cells from acromegalic patients, as determined by the reverse hemolytic plaque assay: effects of SMS 201-995, GH-releasing hormone and thyrotropin-releasing hormone.

We used the reverse hemolytic plaque assay to study the dynamics of GH secretion by individual pituitary adenoma cells from eight acromegalic patients. There was a considerable variation between the adenomas with respect to the percentages of GH-secreting cells (25-78.5%) and also with respect to the amount of GH released per individual pituitary adenoma cell (mean plaque areas varying from 901-3559 micron 2).

The effects of bromocriptine, thyrotropin-releasing hormone, and gonadotropin-releasing hormone on hormone secretion by gonadotropin-secreting pituitary adenomas in vivo and in vitro.

The characteristics and dynamics of hormone secretion in vivo and in vitro were investigated in six patients with gonadotropin-secreting pituitary adenomas. All six tumors secreted and contained FSH and different combinations of LH, beta-LH, and alpha-subunit. In addition, immunohistochemical examination of the pituitary tumor tissue showed staining with both LH and FSH in three and either LH or FSH in the other three tumors.

The sensitivity of growth hormone and prolactin secretion to the somatostatin analogue SMS 201-995 in patients with prolactinomas and acromegaly.

The somatostatin analogue SMS 201-995 has recently been shown to be effective in suppressing GH secretion in most acromegalic patients. In the present study it was investigated whether PRL release in prolactinoma and acromegalic patients might also be sensitive to SMS 201-995 and whether co-secretion of PRL in acromegaly plays a role in determining the sensitivity of GH secretion to SMS 201-995. The s.

Intracerebral malignant schwannoma.

A case of highly malignant primary intracerebral schwannoma is presented in a boy aged 15 years. The histological, ultrastructural and immunocytochemical properties were consistent with a partly epithelioid schwannoma. All reports so far published of 18 intracerebral schwannomas were of benign tumors, one case was semi-malignant.

Characterization of monoclonal antibodies raised against the prostatic cancer cell line PC-82.

For production of monoclonal antibodies (McAbs), hybrid cells were prepared by fusion of spleen cells of BALB/c mice immunized with the human prostatic cancer cell line PC-82 and the P3-X6(3)Ag8.653 murine myeloma cell line. Supernatants of approximately 500 hybrid clones were screened for prostate specific antibodies using an ELISA on PC-82 cells.

Different responses of growth hormone secretion to guanfacine, bromocriptine, and thyrotropin-releasing hormone in acromegalic patients with pure growth hormone (GH)-containing and mixed GH/prolactin-containing pituitary adenomas.

There is great variability in the GH secretory responses to different stimuli in patients with acromegaly. In the present study, we compared the effects on GH secretion of two compounds (bromocriptine and TRH), which presumably act directly at the pituitary level, with the effect of the centrally acting alpha-adrenergic agonist guanfacine in 14 untreated acromegalic patients. These in vivo responses of GH release were correlated with the results of immunocytochemical studies of the pituitary adenomas.

The role of prolactin in the inhibitory action of bromocriptine on growth hormone secretion in acromegaly.

Unlabelled: Bromocriptine treatment results in clinical improvement and inhibition of plasma GH levels in only part of the acromegalic patients. The possible role of the simultaneous presence of Prl and GH in GH-secreting pituitary adenomas was investigated with regard to the inhibitory action of bromocriptine on GH secretion and the paradoxical increase of GH release in reaction to TRH. Surgically obtained pituitary tumour tissue from 35 consecutive acromegalic patients was studied immunohistochemically.