Biomedical subjects

N Sanno

Publications and source records attributed to N Sanno.

At least 55 records · Page 3Linked to original sources

PubMed1997

Proliferative potential in pituitary adenomas: measurement by monoclonal antibody MIB-1.

The proliferative potential of 45 pituitary adenomas was compared with their biological behaviour as determined by immunohistochemical studies, radiological findings, and clinical manifestations. The PCI (proliferating cell index) as measured using antibody MIB-1 in this study ranged from 0.05 to 4.80%, with an average PCI of 1.49 +/- 0.19% (mean +/- standard error of the mean). There was no significant correlation between proliferation and hormonal state, maximum size, intra-adenomatous haemorrhage, or invasiveness. However, a PCI > or = 1.5% appeared to correlate with the likelihood of tumour regrowth (regrowth rate: 50%); for PCIs < 1.5%, the rate was 16%. Regrowth adenomas had a higher mean MIB-1 PCI than non-regrowth adenomas [2.34 +/- 0.58% (SE) versus 1.14 +/- 0.16%, p < or = 0.05]. MIB-1 PCIs may provide information that is useful for planning follow-up studies and treatment after surgical resection.

Adenoma↗

PubMed1997

A rare case of gastric cancer in an acromegalic patient.

Although it has been demonstrated that acromegalic patients have an increased risk of neoplasms, especially colon neoplasms, gastric cancer with acromegaly is very rare--only five cases have been reported to date in Japan. We report here a rare case of gastric cancer with acromegaly in a 58-year-old woman, whose acromegalic change began at age 44. This patient showed typical clinical features of acromegaly, with increased concentrations of blood growth hormone (GH) and insulin-like growth factor I (IGF-I); she had four types of neoplasms; gastric cancer, colon tubular adenoma with moderate atypia, pancreatic mucinous cystadenoma, and subcutaneous lipoma. The gastric cancer was macroscopically 0-IIc type, 3.0 x 2.5 cm in size, and histologically diagnosed as a poorly differentiated adenocarcinoma with limited invasion of the mucosal layer. The previously documented stimulatory effects of GH and/or IGF-I on tumorigenesis and cell proliferation may have been responsible for the development of the multiple neoplasms in our patient.

Acromegaly↗

PubMed1997

Malignant carcinoid tumor of the anterior mediastinum metastasis to a prolactin-secreting pituitary adenoma: a case report.

BACKGROUND: Although the pituitary gland is known to harbor metastatic deposits, metastasis from a carcinoid tumor is extremely rare. Metastasis to a pituitary adenoma also is an infrequent occurrence. CASE REPORT: A case of malignant carcinoid tumor of the anterior mediastinum with metastasis to a prolactin-secreting pituitary adenoma is presented in this 46-year-old woman. This metastatic pituitary tumor demonstrated a high proliferative potential. CONCLUSION: To our knowledge, this case represents the first documentation of metastasis from a malignant carcinoid tumor to a pituitary adenoma.

Carcinoid Tumor↗

PubMed1997

Immunohistochemical detection of human natural killer cell like immunoreactivity in human pituitary adenomas, using monoclonal antibody NK-1.

Natural killer (NK) cells are specialized lymphocytes which are characterized as non-T and non-B cells, as they lack classic T and B cell surface markers. Recently, NK like immunoreactivity has been identified in endocrine and neuronal tissues as well as in the tumors derived from the neuroectoderm and neuroendocrine system. We examined the expression of NK-1 like immunoreactivity in 6 normal pituitary glands and in 55 cases of neoplastic pituitaries (16 growth hormone (GH) producing adenomas, 14 prolactin (PRL) producing adenomas, 4 thyrotropin (TSH) producing adenomas, 5 adrenocortocitropin (ACTH) producing adenomas and 16 non-functioning adenomas) immunohistochemically. The expression of the S-100 protein, which is a marker for folliclo-stellate (FS) cells, which have been reported to secrete cytokines as immuno-endocrine modulators, were also examined. In normal pituitary glands, NK-1 was detected in all 6 tissues in the cytoplasm of about 5-10% of the anterior pituitary cells. By serial sectioning and double immunostaining, NK-1 immunopositivity was frequently found to be localized in ACTH cells. The colocalization with other anterior pituitary hormones such as GH. PRL, the beta-subunit of luteinizing hormone (LH beta), follicle stimulating hormone (FSH beta). TSH beta and alpha-subunit of glycoprotein (alpha SU) was not observed. The S-100 immunopositive FS cells, which were scattered among hormone producing cells, were closely associated with NK-1 immunoreactive cells in the normal pituitaries. Among the 55 cases of pituitary adenomas, NK-1 was present in all the types of pituitary tumors, and a total of 33 (60.0%) contained NK-1 positive tumor cells. The frequency of NK-1 immunoreactivity in the individual adenoma types was; 14 of 16 GH producing adenomas (87.5%), 7 of 14 PRL producing adenomas (50%). 3 of 4 TSH producing adenomas (75%), 3 of 5 ACTH producing adenomas (60%), and 5 of 16 nonfunctioning adenomas (31.3%). By double immunostaining, NK-1 was found to be frequently colocalized with ACTH in ACTH producing adenomas, and was colocalized with PRL in PRL producing adenomas, or with GH, PRL or the alpha-subunit in GH producing adenoma cells. NK-1 immunoreactive cells were observed in close association with S-100 immunopositive FS cells in the adenomas. Our results may indicate that NK-1 positive cells may have functions as a paracrine modulators of their neighboring cells, which includes S-100 positive FS cells.

Adenoma↗

PubMed1997

Immunohistochemical expression of retinoid X receptor isoforms in human pituitaries and pituitary adenomas.

Retinoid X receptors (RXRs) are transcriptional factors that belong to the steroid/thyroid hormone receptor superfamily. There are 3 RXR isoforms-alpha, beta, gamma-known to bind 9-cis-retinoic acid as their ligand. The expression of RXRs in human pituitary glands and pituitary adenomas has not been extensively investigated. To determine whether specific RXR isoforms may play roles in the state of differentiation of pituitary adenomas, we have investigated the immunohistochemical expression of RXR alpha and RXR gamma in 6 nontumorous pituitaries and in 60 different pituitary adenomas using isoform-specific antibodies. In the nontumorous pituitaries. RXR alpha was expressed in the nuclei of almost all cells, while RXR gamma was only expressed in thyrotropin (TSH) cells and in some cells positive for growth hormone (GH) and glycoprotein alpha-subunit (alpha SU) but not in luteinizing hormone (LH) beta-subunit, follicle-stimulating hormone (FSH) beta-subunit, prolactin (PRL) or adrenocorticotropin (ACTH) cells by double immunostaining. All 60 adenomas were RXR alpha positive, and 39 of 60 adenomas (65%) were positive for RXR gamma. The incidence of RXR gamma immunoreactivity in the different adenoma types was: 13 of 16 GH-producing adenomas (81.3%), 9 of 14 PRL-secreting adenomas (64.3%), 6 of 6 TSH-secreting adenomas (100%), 2 of 5 ACTH-secreting adenomas (40%) and 9 of 19 nonfunctioning adenomas (47.4%) including immunohistochemically gonadotropin-subunit-positive adenomas. The colocalization of RXR gamma with the TSH beta subunit, GH and alpha SU in the same adenoma cells was frequently observed, and sometimes RXR gamma was colocalized with PRL, ACTH, FSH beta or LH beta as shown by double immunostaining. We conclude that RXR alpha is expressed in both human pituitaries and pituitary adenomas. In contrast, RXR gamma is expressed more broadly in pituitary adenomas than in normal pituitaries and thus may play a role in the differentiation-specific cell types in the human pituitary both under physiological and pathological conditions.

Adenoma↗

PubMed1997

Modulation of protein kinases and microtubule-associated proteins and changes in ultrastructure in female rat pituitary cells: effects of estrogen and bromocriptine.

This study focused on the intracellular signal transduction system and microtubule-associated proteins (MAPs), such as MAP-2 and Tau protein. The modulation of these proteins and their correlation with ultrastructural changes were investigated in rat pituitary prolactin (PRL) cells. Adult female Wistar rats were treated with estrogen and bromocriptine and their pituitary glands were removed for analysis of the expression of tubulin, MAP-2, Tau protein, protein kinase C (PKC), and calcium calmodulin (CaM) kinase. Western blot analysis showed that estrogen increased and bromocriptine decreased the expression of PKC alpha, beta 1, beta 2, CaM kinase alpha, beta, MAP-2, and Tau protein. MAP-2 and Tau protein, which are cytosolic proteins, being translated on free ribosomes, were associated with the membrane of whirling rough endoplasmic reticulum (RER) in estrogen-treated cells and dissociated with vesiculated RER induced by bromocriptine. These results suggested that the modulation of MAP-2 and Tau protein may reflect changes of PKC and CaM kinase, and that the quantitative changes and intracellular modulation of MAPs induced by estrogen and bromocriptine, i.e., estrogen-induced association and bromocriptine-induced dissociation of MAP-2 and Tau protein with membrane of RER, may reflect the dynamics of microtubules and are associated with structural changes in the RER and changes in the synthesis and intracellular transport of PRL.

Animals↗

PubMed1997

Retinoid X receptors in the kidney: their protein expression and functional significance.

Retinoid X receptors (RXRs) heterodimerize with 1,25-dihydroxyvitamin D3 (VD) receptor (VDR), and play important roles in VD-regulated transactivation. VD acts on many tissues including kidney for the regulation of calcium homeostasis. In the kidney, the expression of VDR in the tubular cells has been well studied. In contrast, little is known about the localization and the functional significance of RXRs there. In order to elucidate these questions, we first performed immunohistochemical analyses of rat kidney using isoform-specific antimouse RXR antibodies we have previously reported. Interestingly, all RXR isoforms, predominantly RXR alpha, mainly localized to the proximal and the distal tubules, but not to the glomeruli. The serial section staining using anti-VDR antibody showed the colocalization of RXR alpha and VDR in those tubular cells. In order to elucidate the functional significance of endogenous receptors in the tubular cells, we next performed transient transfection studies using the tubular-cell derived Madin-Darby bovine kidney cells, which express both endogenous VDR and RXR. We transfected a reporter plasmid containing direct repeat 3 (DR3) sequence, to which only RXR/VDR heterodimer can bind, and found that VD and 9-cis retinoic acid, as well as VD and RXR selective agonist LG100153, had an additive effect for the DR3 transactivation. Taken together, we speculate that endogenous RXRs co-localize with VDR, and coregulate VD-dependent genes in the tubular cells of the kidney as RXR/VDR heterodimer.

Animals↗

PubMed1997

Gonadotropin-releasing hormone and gonadotropin-releasing hormone receptor messenger ribonucleic acids expression in nontumorous and neoplastic pituitaries.

In the nontumorous pituitary, GnRH stimulates the release and synthesis of LH and FSH by gonadotroph cells via the GnRH receptor (GnRH-R). Little is known, however, about expression of GnRH and GnRH-R messenger RNAs (mRNAs) in nontumorous pituitary tissue and in adenomas. To learn more about the distribution and regulatory roles of GnRH and its receptor, we investigated the expression of both GnRH and GnRH-R mRNAs in nontumorous human pituitary and in various types of pituitary adenomas using the RT-PCR, in situ hybridization, and in situ hybridization in combination with RT-PCR (in situ RT-PCR). Using RT-PCR, GnRH mRNA was found to be expressed in normal human pituitaries and in all types of adenomas. Similarly, GnRH-R mRNA was expressed in nontumorous human pituitaries and in most, but not all, adenomas. These included 5 gonadotroph adenomas, 6 null cell adenomas, 1 of 2 GH-producing tumors, and 1 of 2 ACTH-producing adenomas, but not in the 2 PRL-producing adenomas examined. In situ hybridization studies showed GnRH and GnRH-R mRNAs in all 3 nontumorous pituitaries and in 12 of 33 (36.4%) and 10 of 33 adenomas (30.3%), respectively. Using an indirect in situ RT-PCR technique to increase the sensitivity of the in situ localization, GnRH and GnRH-R mRNAs were detected in 29 (87.9%) and 25 (75.8%) of 33 adenomas, respectively. This is the first report of the localization of GnRH and GnRH-R mRNAs in individual pituitary adenoma cells using in situ RT-PCR. The frequent expression of GnRH and GnRH-R mRNAs in pituitary cells suggests that GnRH has autocrine/paracrine functions in nontumorous and neoplastic pituitary tissues.

Gonadotropin-Releasing Hormone↗

PubMed1997

A growth hormone-releasing hormone-producing pancreatic islet cell tumor metastasized to the pituitary is associated with pituitary somatotroph hyperplasia and acromegaly.

The functional and morphological changes in the pituitary gland caused by a GHRH-producing pancreatic islet cell tumor that metastasized to the pituitary and caused somatotroph hyperplasia are described. A 52-yr-old woman presented with loss of visual acuity, diabetes insipidus, and acromegaly caused by a GHRH-producing endocrine carcinoma metastasized to the pituitary. The serum GHRH, GH, and insulin-like growth factor I levels of the patient were elevated. Immunohistochemical and in situ hybridization study revealed GHRH immunoreactivity and GHRH messenger RNA (mRNA) in the metastatic tumor cells. The anterior pituitary showed hyperplasia of somatotroph cells with intact acinar structure that did not contain an adenoma, determined by light microscopy using silver impregnation. Electron microscopy revealed hyperplastic characteristics of densely granulated somatotrophs. In situ hybridization documented strong signals for GH mRNA and pituitary-specific transcriptional factor Pit-1 mRNA in the hyperplastic somatotrophs. A weak signal for GHRH receptor mRNA was detected in these somatotrophs. However, using in situ RT-PCR, GHRH receptor mRNA was more conclusively observed in most of the somatotrophs. The excessive production of GHRH by metastatic tumor may have resulted in somatotroph hyperplasia by the synergistic effects of Pit-1 and GHRH receptor. It can be concluded that the pathogenesis of pituitary adenoma formation is primarily mediated by other factors than hypothalamic hormone.

Acromegaly↗

PubMed1997

Transforming growth factor-beta, transforming growth factor-beta receptor II, and p27Kip1 expression in nontumorous and neoplastic human pituitaries.

Transforming growth factor (TGF)-beta has been implicated in the regulation of normal and neoplastic anterior pituitary cell function. TGF-beta regulates the expression of various proteins, including p27Kip1 (p27), a cell cycle inhibitory protein. We examined TGF-beta, TGF-beta type II receptor (TGF-beta-RII), and p27 expression in normal pituitaries, pituitary adenomas, and carcinomas to analyze the possible roles of these proteins in pituitary tumorigenesis. Normal pituitary, pituitary adenomas, and pituitary carcinomas all expressed TGF-beta and TGF-beta-RII immunoreactivity. Reverse transcription polymerase chain reaction analysis showed TGF-beta 1, -beta 2, and -beta 3 isoforms and TGF-beta-RII in normal pituitaries and pituitary adenomas. Pituitary adenomas cells cultured for 7 days in defined media showed a biphasic response to TGF-beta with significant inhibition of follicle-stimulating hormone secretion at higher concentrations (10(-9) mol/L) and stimulation of follicle-stimulating hormone secretion at lower concentrations (10(-13) mol/L) of TGF-beta 1 in gonadotroph adenomas. Immunohistochemical analysis for p27 protein expression showed the highest levels in nontumorous pituitaries with decreased immunoreactivity in adenomas and carcinomas. When nontumorous pituitaries and various adenomas were analyzed for p27 and specific hormone production, growth hormone, luteinizing hormone, and thyroid-stimulating hormone cells and tumors had the highest percentages of cells expressing p27, whereas adrenocorticotrophic hormone cells and tumors had the lowest percentages. Immunoblotting analysis showed that adrenocorticotrophic hormone adenomas also had the lowest levels of p27 protein. Semiquantitative reverse transcription polymerase chain reaction and Northern hybridization analysis did not show significant differences in p27 mRNA expression in the various types of adenomas or in nontumorous pituitaries. In situ hybridization for p27 mRNA showed similar distributions of the gene product in nontumorous pituitaries, pituitary adenomas, and carcinomas. These results indicate that TGF-beta and TGF-beta-RII are widely expressed in nontumorous pituitaries and in pituitary neoplasms and that TGF-beta 1 regulates pituitary hormone secretion. The levels of the TGF-beta-regulated protein p27 decreases in the progression of normal to neoplastic pituitaries. In contrast, the mRNA levels of p27 remained relatively constant in nontumorous pituitaries, pituitary adenomas, and carcinomas, indicating that p27 protein levels in adenomas and carcinomas are regulated by translational and post-translational mechanisms.

Adenoma↗

PubMed1996

A case of pituitary somatotroph adenoma with concomitant secretion of growth hormone, prolactin, and adrenocorticotropic hormone--an adenoma derived from primordial stem cell, studied by immunohistochemistry, in situ hybridization, and cell culture.

Somatotroph adenomas often secrete prolactin (PRL) besides growth hormone (GH) and are sometimes immunostained for other anterior pituitary hormones or their subunits, such as thyroid-stimulating hormone (TSH) beta-subunit and glycoprotein hormone alpha-subunit (alpha SU). However, somatotroph adenomas showing hypersecretion of adrenocorticotropic hormone (ACTH) are extremely rare. There have been, to our knowledge, only five published reports on somatotroph adenomas accompanied by excessive ACTH secretion. Here we report a case of intracavernously invading somatotroph macro-adenoma with high serum GH, PRL, and ACTH levels. We examined the case using immunohistochemistry (IHC), in situ hybridization (ISH), and cell culture, and confirmed GH, PRL, and ACTH, as well as alpha SU, production, and the expression of Pit-1 protein by the adenoma, which is known as a transcriptional factor for GH, PRL, and TSH, not for ACTH. Therefore, the presence of unknown transcriptional factor other than Pit-1, common to GH, PRL, and ACTH, may be speculated to be expressed in this adenoma. In our previous study, we had found plurihormonal mRNA expression, especially for ACTH, the beta-subunit of follicle-stimulating hormone and luteinizing hormone in some somatotroph adenomas, using non-radio-isotopic ISH, and suggested that these adenomas might be derived from plurihormonal primordial stem cells. Our present case is significant from the viewpoint of histogenesis of pituitary adenomas, because it further supports the cell origin of somatotroph adenomas from plurihormonal primordial stem cells, and moreover it suggests the presence of unknown transcriptional factor other than Pit-1, common to GH, PRL, and ACTH.

Adenoma↗

PubMed1996

Clinical and cytofunctional classification of pituitary adenomas: proposal of a new classification.

Recent methodological advances in immunohistochemistry, ultrastructural techniques, hormonal assays, resolution imaging and molecular biology techniques have provided new insights into the pathology, function and cytogenesis of pituitary adenomas. Pituitary adenomas have been classified historically on the basis of tinctorial affinities, followed by the basis of ultrastructure and immunohistochemistry. The current development of technologies necessitate the new classification of pituitary adenomas which integrates these numerous parameters as well as the clinical manifestations. For this purpose, we suggest a new clinico-cytofunctional classification of pituitary adenomas, which is based on these clinical manifestations and integrates the information on biology, imaging function and ultrastructure. This classification which corresponds to current advances will not only provide pertinent clinical data but facilitate better understanding of the biology and nature of these complexed lesions.

Adenoma↗

PubMed1996

Simultaneous ultrastructural identification of growth hormone and its messenger ribonucleic acid using combined immunohistochemistry and non-radioisotopic in situ hybridization: a technical note.

The present electron microscopical study is concerned with the simultaneous visualization of messenger ribonucleic acid (mRNA) and its encoded protein in the same specimen. Pre-embedding electron microscopical in situ hybridization (EM-ISH) on rat pituitary gland tissue localized growth hormone mRNA in the polysomes of the rough endoplasmic reticulum, and subsequent postembedding immunolabelling using protein A-colloidal gold particles identified growth hormone mainly in the secretory granules. We believe that our report provides the first simultaneous ultrastructural identification of mRNA and its encoded protein using combined pre-embedding EM-ISH and immunohistochemistry. In this method, the signals for mRNA were localized specifically as highly electron dense products on the polysomes of the endoplasmic reticulum, and those for its encoded protein were recognized as gold particles both in the cisternae of the reticulum and in the secretory granules. Our ultrastructural double labelling method for mRNA and protein may provide a tool to find important clues for elucidating the intracellular correlation of mRNA translation and secretion of translated protein, because of its high resolution, good morphological preservation, and the specific localization of the reaction products.

Animals↗

PubMed1996

In situ hybridization analysis of Pit-1 mRNA and hormonal production in human pituitary adenomas.

The pituitary-specific transcriptional factor, Pit-1, is a member of the POU-domain family which has a role in the development and differentiation of three pituitary cell types: somatotrophs, lactotrophs, and thyrotrophs. Recent investigations have suggested the involvement of specific regulation of Pit-1 transcripts in human pituitary adenomas. In this study, we analyzed the expression of Pit-1 gene and Pit-1 product in various human pituitary adenomas using in situ hybridization (ISH) and immunohistochemistry (IHC). Northern hybridization analysis revealed 2.4- and 4.1-kb Pit-1 transcripts in normal pituitary, growth hormone (GH)-, prolactin (PRL)- and thyrotropin (TSH)-secreting adenomas. By ISH analysis, Pit-1 mRNA was detected in 42 (84%) of 50 adenomas. The highest incidence was observed in 15 GH-secreting adenomas and 8 TSH-secreting adenomas, in which Pit-1 mRNA was detected in all cases. Pit-1 mRNA expression was detected in 11 (85%) of 13 PRL-secreting adenomas. In 12 clinically non-functioning adenomas, Pit-1 mRNA was also present in 8 cases, and 5 of these were associated with immunohistochemical expression of Pit-1 product. By combined ISH and IHC, Pit-1 mRNA was often colocalized with GH, PRL or TSH beta immunoreactivities and sometimes colocalized with alpha-subunit of glycoprotein (alpha SU) immunoreactivity. The expression of Pit-1 mRNA in various cell types of human pituitary adenomas in addition to GH, TSH beta and PRL immunoreactivities suggests that Pit-1 may play a role in functional development of pituitary adenomas, including clinically non-functioning adenomas. However, some additional transcriptional factors or enhancers may be required.

Adenoma↗

PubMed1996

Application of catalyzed signal amplification in immunodetection of gonadotropin subunits in clinically nonfunctioning pituitary adenomas.

Pituitary adenomas that are characterized by the absence of a particular clinical syndrome and the absence of excessive hormone secretion have been classified as nonfunctioning adenomas. Recent development of immunohistochemical analysis and hormonal assay have suggested that many of these tumors have function to secret the gonadotropin subunits. A novel procedure biotin amplification in immunohistochemistry, catalyzed signal amplification (CSA) has been reported recently. In this study, the authors applied this new method to tissues from 50 cases of clinically nonfunctioning adenomas. These cases had no evidence of endocrinological signs by hormone secretion. When the CSA system was applied in normal pituitary gland, each of subunits was positive even when the antibody was diluted 1:1,000,000, which is 1,000 folds of standard indirect immunoperoxidase method. Immunohistochemical staining by indirect immunohistochemical method revealed that all 50 adenomas were negative for all the anterior hormones, including growth hormone (GH), prolactin (PRL), adrenocorticotropic hormone (ACTH), beta-subunit of luteinizing hormone (LH beta), follicle-stimulating hormone (FSH beta), thyroid stimulating hormone (TSH beta), and a-subunit of glycoprotein (alpha SU). Using avidin-biotin complex (ABC) method, two cases were positive for FSH beta and four cases were positive for alpha SU, respectively, and the immunopositivities were observed weakly in scattered cells. By CSA system, 26 cases of 50 nonfunctioning adenoma were positive for FSH beta, 16 cases were positive for LH beta, and 29 cases were positive for alpha SU, respectively. The immunoreactivities were clearly observed in cytoplasm of many adenoma cells. This amplification procedure provides a means of greatly increasing the sensitivity of the immunohistochemistry including subunits of glycoproteins that are difficult to detect by previous indirect immunoperoxidase method or ABC method. This amplification procedure provides a great increase in the sensitivity of the immunohistochemistry for the detection of gonadotropin subunits and suggest that significant proportion of the nonfunctioning adenomas are gonadotropin subunit producing adenomas.

Adenoma↗

PubMed1996

Combined non-isotopic in situ hybridisation and indirect immunohistochemical analysis of hormone production in the rat pituitary gland.

An understanding of the intracellular relation between hormonal expression (storage) and gene expression (production) is essential for elucidating the functional status of the individual cells in endocrine tissue such as the pituitary gland. To this end, mRNA expression was visualised by using a combined in situ hybridisation and immunohistochemistry method in routinely processed, formalin fixed, paraffin wax embedded rat pituitaries. mRNA was detected by non-isotopic in situ hybridisation (alkaline phosphatase antialkaline phosphatase method, with nitroblue tetrazolium and 5-bromo-4-chloro-3-indolylphosphate as substrates). Sections were then stained by using the immunoperoxidase method to demonstrate pituitary hormone expression. The specificity of the combined staining method was confirmed by staining adjacent sections separately. The antigenicity of rat growth hormone and prolactin was adequately preserved following hybridisation. In conclusion, this method is specific, easy to use and permits the determination of the functional status of individual cells.

Journal Article↗

PubMed1996

Cyclic Cushing's disease in long-term remission with a daily low dose of bromocriptine.

A 56-year-old male patient with cyclic Cushing's disease remained in a state of remission for more than one year with a relatively low dose of bromocriptine (2.5-3.75 mg/day). It has been reported that bromocriptine treatment for cyclic Cushing's disease induces only a transient remission; in the most effective cases, a relatively high dose (40 mg/day) was necessary. In the hypercortisolemic state, plasma adrenocorticotropic hormone (ACTH) and serum cortisol were not suppressed by dexamethasone and did not respond to corticotropin-releasing factor (CRF). An antehypophysectomy was not effective, even though the resected tissue contained ACTH-positive microadenomas. The present observations thus indicate the effectiveness of bromocriptine for some patients with this rare disorder.

Adenoma↗

PubMed1996

Brain metastasis from malignant pancreatic somatostatinoma. Case report.

Somatostatinomas are rare endocrine tumors that are located primarily in the pancreas. Metastases are seen most frequently in the liver and lymph nodes. The authors present the case of a 63-year-old man who had a malignant somatostatinoma of pancreatic tail origin that metastasized to the brain 10 years after diagnosis of the primary tumor. The metastatic brain lesions were totally removed and the patient is alive without tumor recurrence 12.3 years after the initial diagnosis. To our knowledge, this case represents the first documentation of brain metastasis from a malignant somatostatinoma, as well as the longest survival time of a patient with a somatostatinoma.

Brain Neoplasms↗