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Sample records for pituitary tumor cell

  1. Pathogenesis of pituitary tumors.

    PubMed

    Yu, Run; Melmed, Shlomo

    2010-01-01

    Pituitary tumors are common and mostly benign neoplasia which cause excess or deficiency of pituitary hormones and compressive damage to adjacent organs. Oncogene activation [e.g. PTTG (pituitary tumor-transforming gene) and HMGA2], tumor suppressor gene inactivation (e.g. MEN1 and PRKAR1A), epigenetic changes (e.g. methylation) and humoral factors (e.g. ectopic production of stimulating hormones) are all possible pituitary tumor initiators; the micro-environment of pituitary tumors including steroid milieu, angiogenesis and abnormal cell adhesion further promote tumor growth. Senescence, a cellular defence mechanism against malignant transformation, may explain the benign nature of at least some pituitary tumors. We suggest that future research on pituitary tumor pathogenesis should incorporate systems approaches, and address regulatory mechanisms for pituitary cell proliferation, development of new animal models of pituitary tumor and isolation of functional human pituitary tumor cell lines. PMID:20541667

  2. Pituitary Tumors

    MedlinePlus

    ... org Tel: 773-577-8750; 800-886-2282 Fax: 847-827-9918 National Brain Tumor Society 55Chapel ... http://www.braintumor.org Tel: 866-455-3214 Fax: 617-924-9998 Pituitary Network Association P.O. ...

  3. Stages of Pituitary Tumors

    MedlinePlus

    ... tumors that may spread to bones of the skull or the sinus cavity below the pituitary gland. ... sella (the bone at the base of the skull , where the pituitary gland sits). Recurrent Pituitary Tumors ...

  4. Pituitary tumor

    MedlinePlus

    ... The pituitary is a small gland at the base of the brain. It regulates the body's balance of many hormones. ... cause symptoms and are never diagnosed during the person's lifetime. ... at the base of the brain. The pituitary helps control the ...

  5. Pituitary Tumors

    MedlinePlus

    ... or milk production), sex hormones (control the menstrual cycle and other sexual functions), thyroid gland hormones (control the thyroid gland), adrenal gland hormones, and vasopressin (a hormone involved in water and electrolyte balance). Symptoms of pituitary adenoma and ...

  6. Concise Review: Paracrine Role of Stem Cells in Pituitary Tumors: A Focus on Adamantinomatous Craniopharyngioma

    PubMed Central

    2016-01-01

    Abstract The existence of tissue‐specific progenitor/stem cells in the adult pituitary gland of the mouse has been demonstrated recently using genetic tracing experiments. These cells have the capacity to differentiate into all of the different cell lineages of the anterior pituitary and self‐propagate in vitro and can therefore contribute to normal homeostasis of the gland. In addition, they play a critical role in tumor formation, specifically in the etiology of human adamantinomatous craniopharyngioma, a clinically relevant tumor that is associated with mutations in CTNNB1 (gene encoding β‐catenin). Mouse studies have shown that only pituitary embryonic precursors or adult stem cells are able to generate tumors when targeted with oncogenic β‐catenin, suggesting that the cell context is critical for mutant β‐catenin to exert its oncogenic effect. Surprisingly, the bulk of the tumor cells are not derived from the mutant progenitor/stem cells, suggesting that tumors are induced in a paracrine manner. Therefore, the cell sustaining the mutation in β‐catenin and the cell‐of‐origin of the tumors are different. In this review, we will discuss the in vitro and in vivo evidence demonstrating the presence of stem cells in the adult pituitary and analyze the evidence showing a potential role of these stem cells in pituitary tumors. Stem Cells 2016;34:268–276 PMID:26763580

  7. Pituitary Tumors: Condition Information

    MedlinePlus

    ... stress. Growth hormone helps control body growth and metabolism. Thyroid-stimulating hormone is involved in growth, body temperature, and heart rate. Nonfunctioning pituitary tumors (also called nonsecretory tumors) do ...

  8. General Information about Pituitary Tumors

    MedlinePlus

    ... tumors that may spread to bones of the skull or the sinus cavity below the pituitary gland. ... sella (the bone at the base of the skull , where the pituitary gland sits). Recurrent Pituitary Tumors ...

  9. Treatment Option Overview (Pituitary Tumors)

    MedlinePlus

    ... tumors that may spread to bones of the skull or the sinus cavity below the pituitary gland. ... sella (the bone at the base of the skull , where the pituitary gland sits). Recurrent Pituitary Tumors ...

  10. Bromocriptine induces parapoptosis as the main type of cell death responsible for experimental pituitary tumor shrinkage

    SciTech Connect

    Palmeri, Claudia Mariela Petiti, Juan Pablo; Valle Sosa, Liliana del; Gutierrez, Silvina; Paul, Ana Lucia de; Mukdsi, Jorge Humberto; Torres, Alicia Ines

    2009-10-01

    Bromocriptine (Bc) produces pituitary tumoral mass regression which induces the cellular death that was classically described as apoptosis. However, recent works have related that other mechanisms of cell death could also be involved in the maintenance of physiological and pathological pituitary homeostasis. The aim of this study was to evaluate and characterize the different types of cell death in the involution induced by Bc in experimental rat pituitary tumors. The current study demonstrated that Bc induced an effective regression of estrogen induced pituitary tumors by a mechanism identified as parapoptosis. This alternative cell death was ultrastructurally recognized by extensive cytoplasmic vacuolization and an increased cell electron density, represented around 25% of the total pituitary cells counted. Furthermore, the results obtained from biochemical assays did not correspond to the criteria of apoptosis or necrosis. We also investigated the participation of p38, ERK1/2 and PKC{delta} in the parapoptotic pathway. An important observation was the significant increase in phosphorylated forms of these MAPKs, the holoenzyme and catalytic fragments of PKC{delta} in nuclear fractions after Bc administration compared to control and estrogen treated rats. Furthermore, the immunolocalization at ultrastructural level of these kinases showed a similar distribution pattern, with a prevalent localization at nuclear level in lactotrophs from Bc treated rats. In summary, we determined that parapoptosis is the predominant cell death type involved in the regression of pituitary tumors in response to Bc treatment, and may cause the activation of PKC{delta}, ERK1/2 and p38.

  11. Familial pituitary tumors.

    PubMed

    Alband, Neda; Korbonits, Márta

    2014-01-01

    Pituitary adenomas are benign intracranial neoplasms that present a major clinical concern due to hormone overproduction and/or tumor mass effects. The majority of pituitary adenomas occur sporadically; however, familial cases are increasingly being recognized, such as multiple endocrine neoplasia type 1 (MEN1), Carney complex (CNC), and familial isolated pituitary adenoma (FIPA). Familial pituitary tumors appear to differ from their sporadic counterparts both in their genetic basis and in clinical characteristics. Evidence suggests that, especially in MEN1 and FIPA, tumors are more aggressive and affect patients at a younger age, therefore justifying the importance of early diagnosis, while in Carney complex pituitary hyperplasia is common. The genetic alterations responsible for the formation of familial pituitary syndromes include the MEN1 gene, responsible for about 80% of MEN1 cases, the regulatory subunit of the protein kinase A, PRKAR1A, responsible for about 70% of Carney complex cases, and AIP, the gene coding the aryl hydrocarbon receptor interacting protein, responsible for about 20% of FIPA cases. Rarely other genes have also been found responsible for familial pituitary adenoma cases. McCune-Albright syndrome (MAS) also has a genetic origin due to mosaic mutations in the G protein-coupled α subunit coded by the GNAS1 gene. In this chapter, we summarize the genetic and clinical characteristics of these familial pituitary syndromes and MAS. PMID:25248598

  12. What Are Pituitary Tumors?

    MedlinePlus

    ... too little makes you sluggish. If a pituitary tumor makes too much TSH, it can cause hyperthyroidism (an overactive thyroid gland). Adrenocorticotropic hormone (ACTH, also known as corticotropin ) causes ...

  13. Inhibition of subcutaneously implanted human pituitary tumor cells in nude mice by LRIG1.

    PubMed

    Wang, X; He, X J; Xu, H Q; Chen, Z W; Fan, H H

    2016-01-01

    The aim of this study was to explore the inhibition of subcutaneously implanted human pituitary tumor cells in nude mice by LRIG1 and its mechanism. For this study, athymic nude mice were injected with either normal pituitary tumor RC-4B/C cells or LRIG1-transfected RC-4B/C cells. We then calculated the volume inhibition rate of the tumors, as well as the apoptosis index of tumor cells and the expression of Ras, Raf, AKt, and ERK mRNA in tumor cells. Tumor cell morphological and structural changes were also observed under electron microscope. Our data showed that subcutaneous tumor growth was slowed or even halted in LRIG1-transfected tumors. The tumor volumes were significantly different between the two groups of mice (χ2 = 2.14, P < 0.05). The tumor apoptosis index was found to be 8.72% in the control group and 39.7% in LRIG1-transfected mice (χ2 = 7.59, P < 0.05). The levels of Ras, Raf, and AKt mRNA in LRIG1-transfected RC-4B/C cells were significantly reduced after transfection (P < 0.01). Transfected subcutaneous tumor cells appeared to be in early or late apoptosis under an electron microscope, while only a few subcutaneous tumor cells appeared to be undergoing apoptosis in the control group. In conclusion, the LRIG1 gene is able to inhibit proliferation and promote apoptosis in subcutaneously implanted human pituitary tumors in nude mice. The mechanism of LRIG1 may involve the inhibition of the PI3K/ Akt and Ras/Raf/ERK signal transduction pathways. PMID:27173312

  14. Pituitary: Non-Secretory Tumors

    MedlinePlus

    ... categories—tumor mass effects and hyposecretion effects. Tumor mass effects Visual field disturbances, most commonly loss of ... surgery. The goal is to completely remove the mass or cyst and preserve normal pituitary, brain, and ...

  15. Pituitary tumor transforming gene-null male mice exhibit impaired pancreatic beta cell proliferation and diabetes

    PubMed Central

    Wang, Zhiyong; Moro, Enrico; Kovacs, Kalman; Yu, Run; Melmed, Shlomo

    2003-01-01

    The mammalian securin, pituitary tumor transforming gene (PTTG), regulates sister chromatid separation during mitosis. Mice or cell lines deficient in PTTG expression, however, are surprisingly viable. Here we show that PTTG disruption in mice (PTTG−/−) severely impairs glucose homeostasis leading to diabetes during late adulthood, especially in males associated with nonautoimmune insulinopenia and reversed alpha/beta cell ratio. Islet beta cell mass in PTTG−/− mice was already diminished before development of frank diabetes and only increased minimally during growth. BrdUrd incorporation of islet cells in PTTG-null mice was ≈65% lower (P < 0.005) than in the WT pancreas, whereas apoptosis rates were similar. PTTG−/− beta cells had pleiotropic nuclei, suggesting defects in cell division. The results indicated that securin is indispensable for normal pancreatic beta cell proliferation. PMID:12626748

  16. Co-regulation of pituitary tumor cell adhesion and prolactin gene expression by glucocorticoid.

    PubMed

    Spangler, P R; Delidow, B C

    1998-01-01

    Rat 235-1 pituitary tumor cells are lactotrophs producing high levels of prolactin (PRL). Dexamethasone (Dex, 100 nM) inhibits PRL gene expression in 235-1 cells by 50%, while simultaneously decreasing cell replication and cell-cell aggregation. To determine the time course of Dex action, we used a quantitative assay for cell-cell interaction, based on the number of single cells present before and after re-aggregation of dispersed cells. 235-1 cells were cultured in growth medium or medium plus 100 nM Dex for 1-4 days before assay. Control cells had 90% re-aggregation on all days of assay. Aggregation of Dex-treated cells decreased to 55% by day 4. Dex treatment also reduced cell numbers by 40%, but this decrease did not contribute to reduced aggregation. To determine the mechanism of Dex-inhibited cell-cell adhesion, we examined the expression of cadherins and catenins. Cadherin-related mRNAs (P- and N-cadherin probes) were detectable in 235-1 cells, but their levels were unchanged by Dex. A pancadherin antibody was unable to detect classical cadherins in these cells. Both alpha- and beta-catenins were detected by Western blotting and their levels were decreased by Dex. Unlike control aggregates, aggregates of Dex-treated cells were able to inhibit expression of PRL mRNA when added to monolayers of 235-1 cells. These data suggest that Dex influences cadherin function by inhibiting catenin expression and that this has the functional consequence of altering 235-1 cell-cell interactions. Overall the data show that Dex affects important aspects of lactotroph function other than PRL gene expression. These changes may include physical alterations in pituitary cell contacts that further support a change in functional state. PMID:9397162

  17. Pertussis toxin inhibits somatostatin-induced K/sup +/ conductance in human pituitary tumor cells

    SciTech Connect

    Yamashita, N.; Kojima, I.; Shibuya, N.; Ogata, E.

    1987-07-01

    The effect of pertussis toxin on somatostatin-induced K/sup +/ current was examined in dissociated human pituitary tumor cells obtained from two acromegalic patients. Somatostatin-induced hyperpolarization or K/sup +/ current was observed in 20 of 23 cells in adenoma 1 and 10 of 11 cells in adenoma 2. After treatment with pertussis toxin for 24 h, these responses were completely suppressed (0/14 in adenoma, 1, 0/10 in adenoma 2). Spontaneous action potentials, K/sup +/, Na/sup +/, and Ca/sup 2 +/ currents were well preserved after pertussis toxin treatment. When crude membrane fraction was incubated with (/sup 32/P)NAD, a 41K protein was ADP-ribosylated by pertussis toxin. Hormone release was inhibited by somatostatin and this inhibition was blocked by pertussis toxin treatment.

  18. Phosphorylation of intracellular proteins related to the multihormonal regulation of prolactin: comparison of normal anterior pituitary cells in culture with the tumor-derived GH cell lines

    SciTech Connect

    Beretta, L.; Boutterin, M.C.; Sobel, A.

    1988-01-01

    We have previously identified a group of cytoplasmic phosphoproteins (proteins 1-11) whose phosphorylation could be related, on a pharmacological basis, to the multihormonal regulation of PRL synthesis and release in the anterior pituitary tumor-derived GH cell lines. Phosphoproteins with identical migration properties on two-dimensional electrophoresis gels were also detectable in normal rat anterior pituitary cells in culture. We designed appropriate culture and (/sup 32/P) phosphate-labeling conditions allowing to analyze the regulation of the phosphorylation of these proteins in normal pituitary cells. TRH, 12-O-tetradecanoylphorbol-13-acetate, and vasoactive intestinal peptide induced the same qualitative changes in phosphorylation of proteins 1-11 in normal as in GH cells. Quantitative differences observed are most likely due to the heterogeneity of primary pituitary cultures. Phosphorylation changes affecting proteins 14-16, not previously detected in GH cells, were also observed with normal anterior pituitary cells. GH cell lines have lost the sensitivity of pituitary lactotrophs for dopamine, an important physiological inhibitor of PRL synthesis and release. In normal anterior pituitary cells in culture, dopamine inhibited also the TRH-stimulated phosphorylation of proteins 1-10, thus strengthening the correlation between phosphorylation of these proteins and multihormonal regulation of pituitary cell functions. Our results indicate: 1) that the same phosphoproteins as in GH cells are related to the multihormonal regulation of nontumoral, normal anterior pituitary cells in culture; 2) that dopamine acts by interfering with the phosphorylation of these proteins.

  19. Pituitary tumor evaluation

    SciTech Connect

    Albertson, B.; Binney, S.

    1995-11-01

    This paper describes research on the following: the structure of {sup 10}B{sub 10}-ovine corticotropin releasing hormone and {sup 10}B{sub 10}-growth hormone releasing hormone; the BNCT effect on AtT-20 cell {sup 10}B{sub 10}-CRH incubations in vitro; BNCT effects on GH{sub 4}C{sub 1} cell {sup 10}B{sub 10} growth hormone releasing factor incubation in vitro; and competitive inhibition of AtT-20 cell BNCT effect.

  20. PRKAR1A and the evolution of pituitary tumors.

    PubMed

    Kirschner, Lawrence S

    2010-09-15

    Carney complex (CNC) is an inherited tumor predisposition associated with pituitary tumors, including GH-producing pituitary adenomas and rare reports of prolactinomas. This disease is caused by mutations in PRKAR1A, which encodes the type 1A regulatory subunit of the cAMP-dependent protein kinase, PKA. Loss of PRKAR1A causes enhanced PKA signaling, which leads to pituitary tumorigenesis. Mutations in the gene have not been detected in sporadic pituitary tumors, but there is some data to suggest that non-genomic mechanisms may cause loss of protein expression. Unlike CNC patients, mice heterozygous for Prkar1a mutations do not develop pituitary tumors, although complete knockout of the gene in the Pit1 lineage of the pituitary produces GH-secreting pituitary adenomas. These data indicate that complete loss of Prkar1a/PRKAR1A is able to cause pituitary tumors in mice and men. The pattern of tumors is likely related to the signaling pathways employed in specific pituitary cell types. PMID:20451576

  1. What Are the Key Statistics about Pituitary Tumors?

    MedlinePlus

    ... factors for pituitary tumors? What are the key statistics about pituitary tumors? About 10,000 pituitary tumors ... Symptoms of Cancer Treatments & Side Effects Cancer Facts & Statistics News About Cancer Expert Voices Blog Programs & Services ...

  2. Somatotroph pituitary tumors in budgerigars (Melopsittacus undulatus).

    PubMed

    Langohr, I M; Garner, M M; Kiupel, M

    2012-05-01

    A series of 11 pituitary tumors in budgerigars were classified on the basis of their clinical, gross, microscopic, and immunohistochemical characteristics. Affected birds were young to middle-aged. Clinically, neurologic signs--including difficulties flying, ataxia, and blindness--were most commonly reported. Additional clinical signs included weight loss, abnormal feathers or molting, increased respiratory efforts, and exophthalmos. Nine birds were diagnosed with chromophobic pituitary adenomas, and 2 birds had chromophobic pituitary carcinomas. Only 1 tumor was delimited to the pituitary gland; the other 10 variably invaded the brain, skull, and retrobulbar space. Distant metastases were identified in 2 birds. All tumors were immunohistochemically strongly positive for growth hormone, consistent with the diagnosis of somatotroph tumors. The common occurrence and early onset may suggest a genetic predisposition of budgerigars to develop somatotroph pituitary tumors with a high incidence of local invasion and with metastatic potential. PMID:21900544

  3. Treatment Options for Pituitary Tumors

    MedlinePlus

    ... brain, including the sella (the bone at the base of the skull , where the pituitary gland sits). ... sphenoid bone (a butterfly-shaped bone at the base of the skull ) to reach the pituitary gland . ...

  4. Pituitary cells in space

    NASA Technical Reports Server (NTRS)

    Hymer, W. C.; Shellenberger, K.; Grindeland, R.

    1994-01-01

    Cells of the mammalian pituitary gland synthesize and secrete several protein hormones which regulate a number of organ systems throughout the body. These include the musculoskeletal, immune, vascular and endocrine systems. Since changes occur in these tissues as a result of spaceflight, and since pituitary growth hormone (GH) and prolactin (PRL) play a role in the control of these systems on earth, we have focused attention over the last 10 years on GH and PRL cell function during and after spaceflight. The cumulative results of 4 spaceflight missions and several mimicked microgravity experiments establish 1) that production and release of biologically active GH and PRL is repeatedly and significantly attenuated (usually >50%) and 2) that changes in cell morphology also occur. In this paper we describe our results within the framework of methodologies and approaches frequently used to study pituitary cell function on earth. In so doing we hope to develop future flight experiments aimed at uncovering possible microgravity 'sensing systems' within the pituitary cell.

  5. Pituitary cells in space

    NASA Astrophysics Data System (ADS)

    Hymer, W. C.; Shellenberger, K.; Grindeland, R.

    1994-08-01

    Cells of the mammalian pituitary gland synthesize and secrete several protein hormones which regulate a number of organ systems throughout the body. These include the musculoskeletal, immune, vascular and endocrine systems. Since changes occur in these tissues as a result of spaceflight, and since pituitary growth hormone (GH) and prolactin (PRL) play a role in the control of these systems on earth, we have focused attention over the last 10 years on GH and PRL cell function during and after spaceflight. The cumulative results of 4 spaceflight missions and several mimicked microgravity (μG) experiments establish 1) that production and release of biologically active GH and PRL is repeatedly and significantly attenuated (usually > 50%) and 2) that changes in cell morphology also occur. In this paper we describe our results within the framework of methodologies and approaches frequently used to study pituitary cell function on earth. In so doing we hope to develop future flight experiments aimed at uncovering possible μG ``sensing systems'' within the pituitary cell.

  6. The retinoblastoma gene in human pituitary tumors

    SciTech Connect

    Cryns, V.L.; Arnold, A.; Alexander, J.M.; Klibanski, A. )

    1993-09-01

    Functional inactivation of the retinoblastoma (RB) tumor suppressor gene is important in the pathogenesis of many human tumors. Recently, the frequent occurrence of pituitary tumors was reported in mice genetically engineered to have one defective RB allele, a genetic background analogous to that of patients with familial retinoblastoma. The molecular pathogenesis of human pituitary tumors is largely unknown, and the potential role of RB gene inactivation in these neoplasms has not been examined. Consequently, the authors studied 20 human pituitary tumors (12 clinically nonfunctioning tumors, 4 somatotroph adenomas, 2 prolactinomas, and 2 corticotrophy adenomas) for tumor-specific allelic loss of the RB gene using a highly informative polymorphic locus within the gene. Control leukocyte DNA samples from 18 of these 20 patients were heterozygous at this locus, permitting genetic evaluation of their paired tumor specimens. In contrast to the pituitary tumors in the mouse model, none of these 18 human tumors exhibited RB allelic loss. These findings indicate that RB gene inactivation probably does not play an important role in the pathogenesis of common types of human pituitary tumors. 24 refs., 1 fig.

  7. High expression of pituitary tumor-transforming gene-1 predicts poor prognosis in clear cell renal cell carcinoma

    PubMed Central

    WEI, CAN; YANG, XIAOLIANG; XI, JUNHUA; WU, WEI; YANG, ZHENXING; WANG, WEI; TANG, ZHIGUO; YING, QUANSHENG; ZHANG, YANBIN

    2015-01-01

    Pituitary tumor-transforming gene-1 (PTTG1) is a recently identified oncogene involved in the progression of malignant tumors; however, the expression level of PTTG1 in clear cell renal cell carcinoma (ccRCC) and its potential value as a novel prognostic marker for ccRCC remains unclear. In this study, PTTG1 mRNA and protein levels were assessed in 44 paired ccRCC tissues and adjacent normal tissues by quantitative polymerase chain reaction (qPCR) and immunohistochemistry, respectively. Further immunohistochemical analysis was implemented in 192 samples of ccRCC to evaluate the associations between PTTG1 levels and the clinical characteristics in ccRCC. Reverse transcription qPCR and immunohistochemical analysis demonstrated that the PTTG1 mRNA and protein levels were significantly higher in ccRCC compared to normal tissues. In addition, the PTTG1 protein level in 192 ccRCC samples was found to be significantly correlated with T stage, N classification, metastasis, recurrence and Fuhrman grade, whereas it was not associated with age and gender. Patients with low PTTG1 levels exhibited a better survival outcome compared to those with a higher PTTG1 level. PTTG1 expression and N stage were identified as independent prognostic factors for the overall survival of ccRCC patients. The results suggested that the overexpression of PTTG1 indicates a poor prognosis in ccRCC patients and, therefore, PTTG1 may serve as a novel prognostic marker for ccRCC. PMID:25798272

  8. What's New in Pituitary Tumor Research and Treatment?

    MedlinePlus

    ... Next Topic Additional resources for pituitary tumors What’s new in pituitary tumor research and treatment? Research into ... of non-functioning adenomas, which may lead to new medical therapies for these tumors. Imaging tests such ...

  9. Morphine-induced desensitization and down-regulation at mu-receptors in 7315C pituitary tumor cells

    SciTech Connect

    Puttfarcken, P.S.; Cox, B.M. )

    1989-01-01

    Pituitary 7315c tumor cells maintained in culture were treated with varying concentrations of morphine from 10 nM to 300 {mu}M, for periods of five or forty-eight hours. The ability of the mu-opioid receptor agonist, DAMGO, to inhibit forskolin-stimulated adenylyl cyclase in washed membrane preparations from the treated cells was compared with its activity in membranes from cells incubated in the absence of added morphine. In the same membrane preparations, the number and affinity of mu-opioid receptors was estimated by measurements of ({sup 3}H)diprenorphine binding. After 5 hr of treatment with morphine concentrations of 100 nM or higher, a significant reduction in inhibition of adenylyl cyclase by DAMGO was observed. Little further loss of agonist activity was observed when the incubations were extended to 48 hr. After 5 hr of morphine treatment, there was no change in either the number of receptors, or their affinity for ({sup 3}H)diprenorphine. However after 48 hr of morphine treatment, greater than 25% reductions in receptor number were apparent with morphine pretreatment concentrations of 10 {mu}M or higher. These results suggest that opioid tolerance in this system is primarily associated with a reduced ability of agonist-occupied receptor to activate the effector system. Receptor down-regulation was not necessary for loss of agonist response, although a reduction in receptor number occurred after exposure to high concentrations of morphine for periods longer than 5hr.

  10. Magnetic Resonance Imaging of Pituitary Tumors.

    PubMed

    Bonneville, Jean-François

    2016-01-01

    Magnetic Resonance Imaging (MRI) is currently considered a major keystone of the diagnosis of diseases of the hypothalamic-hypophyseal region. However, the relatively small size of the pituitary gland, its location deep at the skull base and the numerous physiological variants present in this area impede the precise assessment of the anatomical structures and, particularly, of the pituitary gland itself. The diagnosis of the often tiny lesions of this region--such as pituitary microadenomas--is then difficult if the MRI technology is not optimized and if potential artifacts and traps are not recognized. Advanced MRI technology can not only depict small lesions with greater reliability, but also help in the differential diagnosis of large tumors. In these, defining the presence or absence of invasion is a particularly important task. This review describes and illustrates the radiological diagnosis of the different tumors of the sellar region, from the common prolactinomas, nonfunctioning adenomas and Rathke's cleft cysts, to the less frequent and more difficult to detect corticotroph pituitary adenomas in Cushing's disease, and other neoplastic and nonneoplastic entities. Finally, some hints are given to facilitate the differential diagnosis of sellar lesions. PMID:27003878

  11. Inhibitory action of methadone and its metabolites on erg-mediated K+ current in GH₃ pituitary tumor cells.

    PubMed

    Huang, Mei-Han; Shen, Ai-Yu; Wang, Trey-Shy; Wu, Hui-Ming; Kang, Ya-Fei; Chen, Chia-Tai; Hsu, Tai-I; Chen, Bing-Shuo; Wu, Sheng-Nan

    2011-02-01

    Methadone (Mtd) is a widely used opioid drug associated with the side effect of hyperprolactinemia. The mechanism of how Mtd induces prolactin secretion remains unclear. The effects of Mtd and its two main metabolites (EDDP: (±)-2-ethyl-1,5-dimethyl-3,3-diphenylpyrrolinium percholarate and EMDP: 2-ethyl-5-methyl-3,3-dipnehyl-1-pyrroline) on ion currents were investigated in GH₃ pituitary tumor cells. Hyperpolarization-elicited K+ currents in GH₃ cells bathed in a high-K(+), Ca(2+)-free solution were studied to evaluate the effects of Mtd and other related compounds on the ether-à-go-go-related-gene (erg) K(+) current (I(K(erg))). Mtd suppressed the amplitude of I(K(erg)) in a concentration-dependent manner with an IC(50) value of 10.4 μM. With the aid of a minimal binding scheme, the inhibitory action of Mtd on I(K(erg)) was estimated with a dissociation constant of 8.2 μM. Mtd tended to increase the rate of I(K(erg)) deactivation in a voltage-dependent fashion. EDDP (10 μM) had no effect on I(K(erg)), while EMDP (10μM) slightly suppressed it. In GH₃ cells incubated with naloxone (30 μM), the Mtd-induced inhibition of I(K(erg)) remained unaltered. Under cell-attached voltage-clamp recordings, Mtd increased the frequency of spontaneous action currents with no change in current amplitude. Similarly, Mtd can suppress I(K(erg)) in differentiated NG108-15 cells; dynorphin A(1-13) did not reverse Mtd-induced inhibition of I(K(erg)). This study shows that Mtd has a depressant effect on I(K(erg)), and suggests its ability to affect membrane excitability and prolactin secretion. The cyclization of Mtd, in which EDDP and EMDP are formed, tends to be critical in removal of the Mtd binding to erg K+ channel. PMID:21094671

  12. Hemostatic Disorders in Hormonally Active Pituitary Tumors.

    PubMed

    Świątkowska-Stodulska, R; Babińska, A; Mital, A; Stodulski, D; Sworczak, K

    2015-10-01

    Endocrinopathies encompass heterogeneous diseases that can lead to hemostasis disorders at various stages over their clinical course. Normal hemostasis requires an equilibrium between the processes of coagulation and fibrinolysis, which depend on multiple activators and inhibitors. To date, the influence of various hormonal disorders on the hemostatic system has been assessed many times. The aim of this review was to analyze hemostasis abnormalities that occur in patients with hormonally active pituitary tumors: corticotropinoma, somatotropinoma, prolactinoma, gonadotropinoma and thyrotropinoma. Authors discuss studies that examined coagulation and hemostasis parameters among patients with these tumors, as well as analyze antithrombotic prophylaxis approach for endogenous hypercortisolemia subjects in particular. PMID:26285071

  13. Mucin 1 and poly I:C activates dendritic cells and effectively eradicates pituitary tumors as a prophylactic vaccine.

    PubMed

    Sui, Dehua; Ma, Lixin; Li, Meng; Shao, Wei; Du, Hongpeng; Li, Ke; Li, Zhenzhu; Li, Zefu

    2016-04-01

    Pituitary tumors are the most common type of cancer within the central nervous system. In the present study, the expression levels of mucin 1 (Muc1) were examined in invasive and non‑invasive pituitary tumor samples, and the results of immunohistochemical staining and Western blot analysis demonstrated marked positive expression of Muc1. In addition, Muc1 + polyinosinic:polycytidylic acid (poly I:C) was found to stimulate the expression levels of the surface molecules cluster of differentiation (CD)40, CD83 and CD80, and HLA‑DRm and decreased the expression of CD14 in the dendritic cells, determined using fluorescence‑activated cell sorting. The secretions of interleukin (IL)‑6, tumor necrosis factor‑α and IL‑1β cytokines were also significantly induced, in a dose‑dependent manner. In in vivo experiments, a higher percentage of CD3+CD4+ T lymphocytes was detected, and the levels of interferon‑γ and IL‑2 in the splenocytes were also upregulated. Furthermore, the combination treatment of Muc1 with poly I:C increased anti‑Muc1 IgM and anti‑Muc1 IgG titers, and altered the balance of IgG2a and IgG1, all of which increased the T helper (Th)1 polarized immune response. Thus, the tumor antigen, Muc1, with poly I:C may produce potent protective effects, which polarize immune responses towards Th1, and elicit antitumor immunity to inhibit the progression of pituitary tumors. PMID:26935338

  14. Reprimo (RPRM) Is a Novel Tumor Suppressor in Pituitary Tumors and Regulates Survival, Proliferation, and Tumorigenicity

    PubMed Central

    Xu, Mei; Knox, Aaron J.; Michaelis, Katherine A.; Kiseljak-Vassiliades, Katja; Kleinschmidt-DeMasters, Bette K.; Lillehei, Kevin O.

    2012-01-01

    Reprimo (RPRM), initially identified as a downstream effector of p53-induced cell cycle arrest at G2/M, is a putative tumor suppressor silenced in some types of cancer. In microarrays, the RPRM transcript was repressed 26-fold in gonadotrope (null cell) human pituitary tumors compared with normal pituitary but in the absence of changes in p53. Inhibition of RPRM mRNA was confirmed by RT-PCR in all gonadotrope tumors, most GH samples, and variably in other tumor types. Human pituitary tumors showed no evidence of abnormal promoter hypermethylation as a mechanism of RPRM repression. RPRM stable expression in gonadotrope (LβT2) and GH (GH3) pituitary cells resulted in decreased rates of cell proliferation by 55 and 30%, respectively; however, RPRM reexpression did not alter G2/M transition. In addition, RPRM increased rates of apoptosis in response to growth factor deprivation as assessed by caspase-3 cleavage and nuclear condensation. Clonagenic assays showed a 5.3- and 3.7-fold suppression of colony growth in RPRM-overexpressing LβT2 and GH3 cells, respectively, supporting its role as a tumor suppressor. In cells stably expressing RPRM mRNA, protein levels were actively suppressed due to rapid degradation through ubiquitination and proteasomal targeting. Growth factor withdrawal, as a model of cellular stress, stabilized RPRM protein levels. Together these data suggest that RPRM is transiently up-regulated at a posttranscriptional level in times of cellular stress to restrict cell survival, proliferation, and tumor formation. When RPRM is silenced as in human pituitary tumors, unrestrained growth and tumor progression may occur. PMID:22562171

  15. Estradiol Upregulates c-FLIPlong Expression in Anterior Pituitary Cells.

    PubMed

    Jaita, G; Zárate, S; Ferraris, J; Gottardo, M F; Eijo, G; Magri, M L; Pisera, D; Seilicovich, A

    2016-04-01

    Anterior pituitary cell turnover depends on a tight balance between proliferation and apoptosis. We have previously shown that estrogens sensitize anterior pituitary cells to pro-apoptotic stimuli. c-FLIP (cellular-FLICE-inhibitory-protein) isoforms are regulatory proteins of apoptosis triggered by death receptors. c-FLIPshort isoform competes with procaspase-8 inhibiting its activation. However, c-FLIPlong isoform may have a pro- or anti-apoptotic function depending on its expression level. In the present study, we explored whether estrogens modulate c-FLIP expression in anterior pituitary cells from ovariectomized (OVX) rats and in GH3 cells, a somatolactotrope cell line. Acute administration of 17β-estradiol to OVX rats increased c-FLIPlong expression in the anterior pituitary gland without changing c-FLIPshort expression as assessed by Western blot. Estradiol in vitro also increased c-FLIPlong expression in anterior pituitary cells but not in GH3 cells. As determined by flow cytometry, the percentage of anterior pituitary cells expressing c-FLIP was higher than in GH3 cells. However, c-FLIP fluorescence intensity in GH3 cells was higher than in anterior pituitary cells. FasL increased the percentage of TUNEL-positive GH3 cells incubated either with or without estradiol suggesting that the pro-apoptotic action of Fas activation is estrogen-independent. Our results show that unlike what happens in nontumoral pituitary cells, estrogens do not modulate either c-FLIPlong expression or FasL-induced apoptosis in GH3 cells. The stimulatory effect of estradiol on c-FLIPlong expression could be involved in the sensitizing effect of this steroid to apoptosis in anterior pituitary cells. The absence of this estrogenic action in tumor pituitary cells could be involved in their tumor-like behavior. PMID:26566102

  16. GH3 tumor pituitary cell cytoskeleton and plasma membrane arrangement are determined by extracellular matrix proteins: implications on motility, proliferation and hormone secretion

    PubMed Central

    Azorín, Erika; Romero-Pérez, Beatriz; Solano-Agama, Carmen; de la Vega, María T; Toriz, César G; Reyes-Márquez, Blanca; González-Pozos, Sirenia; Rosales-García, Víctor H; del Pliego, Margarita González; Sabanero, Myrna; Mendoza-Garrido, María E

    2014-01-01

    The extracellular matrix (ECM) influences different physiological and pathophysiological aspects of the cell. The ECM consists in a complex network of macromolecules with characteristic biochemical properties that allow cells to sense their environments inducing different signals and changing cell behavior. The purpose of the present study was to evaluate the participation of different ECM proteins in cell morphology and its implication on motility, proliferation and hormone secretion in GH3 cells, a tumor pituitary cell. GH3 cells were cultured with a defined medium on collagens I/III and IV, fibronectin and laminin. GH3 cells express α2 integrin subunit de novo. The cells responded to the ECM proteins with differentiated cell surface morphologies and membrane protrusions. A rounded shape with small membrane blebs, weak substrate adhesion and high motility was observed in cells on C I/III and fibronectin, while on C IV and laminin cells were viewed elongated and adhered. Differences on actin cytoskeleton, cytoskeletal-associated vinculin and phospho-MLC showed that ECM proteins determine the cytoskeleton organization. Cell proliferation showed dependency on the ECM protein, observing a higher rate in cells on collagen I/III. Prolactin secretion was higher in cells with small blebs, but an unchangeable response to EGF was obtained with the ECM proteins, suggesting is a consequence of cortical actin arrangement. We ascribe the functional differences of the GH3 cells to the cytoskeletal organization. Overall, the data showed that ECM plays a critical role in GH3 cells modulating different cellular comportment and evidenced the importance of the ECM composition of pituitary adenomas. PMID:25057334

  17. HoxD10 gene delivery using adenovirus/adeno-associate hybrid virus inhibits the proliferation and tumorigenicity of GH4 pituitary lactotrope tumor cells

    SciTech Connect

    Cho, Mi Ae; Yashar, Parham; Kim, Suk Kyoung; Noh, Taewoong; Gillam, Mary P.; Lee, Eun Jig Jameson, J. Larry

    2008-07-04

    Prolactinoma is one of the most common types of pituitary adenoma. It has been reported that a variety of growth factors and cytokines regulating cell growth and angiogenesis play an important role in the growth of prolactinoma. HoxD10 has been shown to impair endothelial cell migration, block angiogenesis, and maintain a differentiated phenotype of cells. We investigated whether HoxD10 gene delivery could inhibit the growth of prolactinoma. Rat GH4 lactotrope tumor cells were infected with adenovirus/adeno-associated virus (Ad/AAV) hybrid vectors carrying the mouse HoxD10 gene (Hyb-HoxD10) or the {beta}-galactosidase gene (Hyb-Gal). Hyb-HoxD10 expression inhibited GH4 cell proliferation in vitro. The expression of FGF-2 and cyclin D2 was inhibited in GH4 cells infected with Hyb-HoxD10. GH4 cells transduced with Hyb-HoxD10 did not form tumors in nude mice. These results indicate that the delivery of HoxD10 could potentially inhibit the growth of PRL-secreting tumors. This approach may be a useful tool for targeted therapy of prolactinoma and other neoplasms.

  18. Evidence of cellular senescence during the development of estrogen-induced pituitary tumors.

    PubMed

    Sabatino, Maria Eugenia; Petiti, Juan Pablo; Sosa, Liliana Del Valle; Pérez, Pablo Anibal; Gutiérrez, Silvina; Leimgruber, Carolina; Latini, Alexandra; Torres, Alicia Inés; De Paul, Ana Lucía

    2015-06-01

    Although pituitary adenomas represent 25% of intracranial tumors, they are usually benign, with the mechanisms by which these tumors usually avoid an invasive profile and metastatic growth development still remaining unclear. In this context, cellular senescence might constitute a plausible explanation for the benign nature of pituitary adenomas. In this study, we investigated the emergence of cellular senescence as a growth control mechanism during the progression of estrogen-induced pituitary tumors. The quantification of Ki67-immunopositive cells in the pituitaries of estrogenized male rats after 10, 20, 40, and 60 days revealed that the mitogenic potential rate was not sustained for the whole period analyzed and successively decreased after 10 days of estrogen exposure. In addition, the expression of cellular senescence features, such as the progressive rise in the enzymatic senescence-associated b-galactosidase (SA-b-gal) activity, IL6, IL1b, and TGFb expression, was observed throughout pituitary tumor development. Furthermore, tumoral pituitary cells also displayed nuclear pATM expression, indicating activated DNA damage signaling, with a significant increase in p21 expression also being detected. The associations among DNA damage signaling activation, SA-b-gal expression, and p21 may provide a reliable combination of senescence-associated markers for in vivo pituitary senescence detection. These results suggest a role for this cellular process in the regulation of pituitary cell growth. Thus, cellular senescence should be conceived as a contributing component to the benign nature of pituitary adenomas, thereby influencing the capability of the pituitary gland to avoid unregulated cell proliferation. PMID:25792544

  19. Exome Sequencing of an Adult Pituitary Atypical Teratoid Rhabdoid Tumor

    PubMed Central

    Biswas, Swethajit; Wood, Madeleine; Joshi, Abhijit; Bown, Nick; Strain, Lisa; Martinsson, Tommy; Campbell, James; Ashworth, Alan; Swain, Amanda

    2015-01-01

    Atypical teratoid rhabdoid tumors (AT/RTs) are rare pediatric brain tumors characterized by bialleic loss of the SMARCB1 tumor suppressor gene. In contrast to pediatric AT/RT that has a simple genome, very little is known about the adult AT/RT genomic landscape. Using a combination of whole-exome sequencing and high-resolution SNP array in a single adult pituitary AT/RT, we identified a total of 47 non-synonymous mutations, of which 20 were predicted to cause non-conservative amino acid substitutions, in addition to a subclone of cells with trisomy 8. We suggest that adult AT/RT may not be markedly dissimilar to other adult brain tumors where mutations in a range of genes, reflecting the functional specialization of different brain regions, but including SMARCB1 inactivation, may be required for its pathogenesis. PMID:26557502

  20. RNAi-mediated knockdown of pituitary tumor-transforming gene-1 (PTTG1) suppresses the proliferation and invasive potential of PC3 human prostate cancer cells

    PubMed Central

    Huang, S.Q.; Liao, Q.J.; Wang, X.W.; Xin, D.Q.; Chen, S.X.; Wu, Q.J.; Ye, G.

    2012-01-01

    Pituitary tumor-transforming gene-1 (PTTG1) is a proto-oncogene that promotes tumorigenesis and metastasis in numerous cell types and is overexpressed in a variety of human tumors. We have demonstrated that PTTG1 expression was up-regulated in both human prostate cancer specimens and prostate cancer cell lines. For a more direct assessment of the function of PTTG1 in prostate tumorigenesis, RNAi-mediated knockdown was used to selectively decrease PTTG1 expression in PC3 human prostate tumor cells. After three weeks of selection, colonies stably transfected with PTTG1-targeted RNAi (the knockdown PC3 cell line) or empty vector (the control PC3 cell line) were selected and expanded to investigate the role of PTTG1 expression in PC3 cell growth and invasion. Cell proliferation rate was significantly slower (28%) in the PTTG1 knockdown line after 6 days of growth as indicated by an MTT cell viability assay (P < 0.05). Similarly, a soft agar colony formation assay revealed significantly fewer (66.7%) PTTG1 knockdown PC3 cell colonies than control colonies after three weeks of growth. In addition, PTTG1 knockdown resulted in cell cycle arrest at G1 as indicated by fluorescence-activated cell sorting. The PTTG1 knockdown PC3 cell line also exhibited significantly reduced migration through Matrigel in a transwell assay of invasive potential, and down-regulation of PTTG1 could lead to increased sensitivity of these prostate cancer cells to a commonly used anticancer drug, taxol. Thus, PTTG1 expression is crucial for PC3 cell proliferation and invasion, and could be a promising new target for prostate cancer therapy. PMID:22872288

  1. Pituitary stem cells: candidates and implications.

    PubMed

    Nassiri, Farshad; Cusimano, Michael; Zuccato, Jeff A; Mohammed, Safraz; Rotondo, Fabio; Horvath, Eva; Syro, Luis V; Kovacs, Kalman; Lloyd, Ricardo V

    2013-09-01

    The pituitary is the master endocrine gland of the body. It undergoes many changes after birth, and these changes may be mediated by the differentiation of pituitary stem cells. Stem cells in any tissue source must display (1) pluripotent capacity, (2) capacity for indefinite self-renewal, and (3) a lack of specialization. Unlike neural stem cells identified in the hippocampus and subventricular zone, pituitary stem cells are not associated with one specific cell type. There are many major candidates that are thought to be potential pituitary stem cell sources. This article reviews the evidence for each of the major cell types and discuss the implications of identifying a definitive pituitary stem cell type. PMID:23423660

  2. Pituitary tumors. Current concepts in diagnosis and management.

    PubMed Central

    Aron, D C; Tyrrell, J B; Wilson, C B

    1995-01-01

    Diagnostic advances have resulted in earlier and more frequent recognition of pituitary tumors. Pituitary tumors cause problems owing to the hormones they secrete or the effects of an expanding sellar mass--hypopituitarism, visual field abnormalities, and neurologic deficits. Prolactin-secreting tumors (prolactinomas), which cause amenorrhea, galactorrhea, and hypogonadism, constitute the most common type of primary pituitary tumors, followed by growth hormone-secreting tumors, which cause acromegaly, and corticotropin-secreting tumors, which cause Cushing's syndrome. Hypersecretion of thyroid-stimulating hormone, the gonadotrophins, or alpha-subunits is unusual. Nonfunctional tumors currently represent only 10% of all clinically diagnosed pituitary adenomas, and some of these are alpha-subunit-secreting adenomas. Insights into the pathogenesis and biologic behavior of these usually benign tumors have been gained from genetic studies. We review some of the recent advances and salient features of the diagnosis and management of pituitary tumors, including biochemical and radiologic diagnosis, transsphenoidal surgery, radiation therapy, and medical therapy. Each type of lesion requires a comprehensive but individualized treatment approach, and regardless of the mode of therapy, careful follow-up is essential. Images PMID:7747500

  3. Acromegaly due to a Macroinvasive Plurihormonal Pituitary Adenoma and a Rectal Carcinoid Tumor

    PubMed Central

    Chin, Sang Ouk; Hwang, Jin-Kyung; Rhee, Sang Youl; Chon, Suk; Oh, Seungjoon; Lee, Misu; Pellegata, Natalia S.

    2015-01-01

    A macroinvasive pituitary adenoma with plurihormonality usually causes acromegaly and hyperprolactinemia, and also accompanies with neurologic symptoms such as visual disturbances. However, its concurrent presentation with a rectal carcinoid tumor is rarely observed. This study reports the history, biochemical, colonoscopic and immunohistochemical results of a 48-year-old female with acromegaly and hyperprolactinemia. Despite the large size and invasive nature of the pituitary adenoma to adjacent anatomical structures, she did not complain of any neurologic symptoms such as visual disturbance or headache. Immunohistochemical staining of the surgical specimen from the pituitary adenoma revealed that the tumor cells were positive for growth hormone (GH), prolactin (PRL), and thyroid stimulating hormone (TSH). Staining for pituitary-specific transcription factor-1 (Pit-1) was shown to be strongly positive, which could have been possibly contributing to the plurihormonality of this adenoma. Colonoscopy found a rectal polyp that was identified to be a carcinoid tumor using immunohistochemical staining. A macroinvasive pituitary adenoma with concomitant rectal carcinoid tumor was secreting GH, PRL, and TSH, which were believed to be in association with over-expression of Pit-1. This is the first case report of double primary tumors comprising a plurihormonal pituitary macroadenoma and rectal carcinoid tumor. PMID:25559714

  4. Dopamine and Somatostatin Analogues Resistance of Pituitary Tumors: Focus on Cytoskeleton Involvement

    PubMed Central

    Peverelli, Erika; Treppiedi, Donatella; Giardino, Elena; Vitali, Eleonora; Lania, Andrea G.; Mantovani, Giovanna

    2015-01-01

    Pituitary tumors, that origin from excessive proliferation of a specific subtype of pituitary cell, are mostly benign tumors, but may cause significant morbidity in affected patients, including visual and neurologic manifestations from mass-effect, or endocrine syndromes caused by hormone hypersecretion. Dopamine (DA) receptor DRD2 and somatostatin (SS) receptors (SSTRs) represent the main targets of pharmacological treatment of pituitary tumors since they mediate inhibitory effects on both hormone secretion and cell proliferation, and their expression is retained by most of these tumors. Although long-acting DA and SS analogs are currently used in the treatment of prolactin (PRL)- and growth hormone (GH)-secreting pituitary tumors, respectively, clinical practice indicates a great variability in the frequency and entity of favorable responses. The molecular basis of the pharmacological resistance are still poorly understood, and several potential molecular mechanisms have been proposed, including defective expression or genetic alterations of DRD2 and SSTRs, or an impaired signal transduction. Recently, a role for cytoskeleton protein filamin A (FLNA) in DRD2 and SSTRs receptors expression and signaling in PRL- and GH-secreting tumors, respectively, has been demonstrated, first revealing a link between FLNA expression and responsiveness of pituitary tumors to pharmacological therapy. This review provides an overview of the known molecular events involved in SS and DA resistance, focusing on the role played by FLNA. PMID:26733942

  5. Pituitary Changes in Prop1 Transgenic Mice: Hormone Producing Tumors and Signet-ring Type Gonadotropes

    PubMed Central

    Egashira, Noboru; Minematsu, Takeo; Miyai, Syunsuke; Takekoshi, Susumu; Camper, Sally A.; Osamura, Robert Y.

    2008-01-01

    Prophet of Pit-1 (Prop1) is an early transcription factor that delays the appearance of gonadotropin in the developing pituitaries. Prop1 transgenic (Tg) mice have been shown to generate pituitary tumors that either produce TSH or are non-hormone producing. In our series of Prop1 Tg mice, only 5 out of 9 female mice produced pituitary adenomas, and the adenomas were only GH, PRL, GH and PRL, PRL and gonadotropin or TSH producing. The pituitary cells that surrounded these adenomas showed hyperplasia of the corresponding hormone producing cells; i.e. the GH cells were increased in the pituitary that contained GH producing adenoma. In addition, although the adenomas lacked the expression of Prop1, the non-neoplastic pituitary cells showed expression of Prop1. The Prop1 Tg mice also showed vacuolated cells with eccentric nuclei, which are characteristic of “signet-ring hypertrophic cells”. Using immunohistochemistry, these signet ring hypertrophic cells were found to be positive for gonadotropin. Taken together, our results suggest a (1) tumorigenic effect of Prop1 in the pituitaries, and (2) causative effects of signet ring-type gonadotropes. PMID:18636109

  6. Pituitary tumors following fallout radiation exposure. [Marshall Islands

    SciTech Connect

    Adams, W.H.; Harper, J.A.; Rittmaster, R.S.; Grimson, R.C.

    1984-08-03

    Two pituitary tumors were diagnosed in a small population of Marshallese accidentally exposed to radioactive fallout in 1954. Endocrinologic findings in the exposed population, are reported and the possible relation of the tumors to radiation exposure and thyroid disease is discussed.

  7. Stellate Cell Networks in the Teleost Pituitary

    PubMed Central

    Golan, Matan; Hollander-Cohen, Lian; Levavi-Sivan, Berta

    2016-01-01

    The folliculostellate cells of the mammalian pituitary are non-endocrine cells that are implicated in long-distance communication and paracrine signaling, but to date, these cells have yet to be characterized in teleosts. We found that the stellate cells of the teleost pituitary share many common attributes with mammalian folliculostellate cells. By labeling of stellate cells in live preparations of tilapia pituitaries we investigated their distribution, association with other endocrine cells and their anatomical and functional coupling. In the pars intermedia, stellate cells were arranged around neuronal bundles and their processes extended into the pars distalis. Within the pars distalis, stellate cells formed close associations with FSH cells and, to a lesser degree, with GH and LH cells, suggesting differential paracrine regulation of the two gonadotrope populations. The production of follistatin by stellate cells further corroborates the notion of a paracrine role on FSH release. We also found stellate cells to form gap junctions that enabled dye transfer to neighboring stellate cells, implicating that these cells form a large-scale network that connects distant parts of the pituitary. Our findings represent the first wide-scale study of stellate cells in teleosts and provide valuable information regarding their functional roles in pituitary function. PMID:27086978

  8. Pertussis toxin modifies the characteristics of both the inhibitory GTP binding proteins and the somatostatin receptor in anterior pituitary tumor cells

    SciTech Connect

    Mahy, N.; Woolkalis, M.; Thermos, K.; Carlson, K.; Manning, D.; Reisine, T.

    1988-08-01

    The effects of pertussis toxin treatment on the characteristics of somatostatin receptors in the anterior pituitary tumor cell line AtT-20 were examined. Pertussis toxin selectively catalyzed the ADP ribosylation of the alpha subunits of the inhibitory GTP binding proteins in AtT-20 cells. Toxin treatment abolished somatostatin inhibition of forskolin-stimulated adenylyl cyclase activity and somatostatin stimulation of GTPase activity. To examine the effects of pertussis toxin treatment on the characteristics of the somatostatin receptor, the receptor was labeled by the somatostatin analog (125I)CGP 23996. (125I)CGP 23996 binding to AtT-20 cell membranes was saturable and within a limited concentration range was to a single high affinity site. Pertussis toxin treatment reduced the apparent density of the high affinity (125I)CGP 23996 binding sites in AtT-20 cell membranes. Inhibition of (125I)CGP 23996 binding by a wide concentration range of CGP 23996 revealed the presence of two binding sites. GTP predominantly reduced the level of high affinity sites in control membranes. Pertussis toxin treatment also diminished the amount of high affinity sites. GTP did not affect (125I)CGP 23996 binding in the pertussis toxin-treated membranes. The high affinity somatostatin receptors were covalently labeled with (125I) CGP 23996 and the photoactivated crosslinking agent n-hydroxysuccinimidyl-4-azidobenzoate. No high affinity somatostatin receptors, covalently bound to (125I)CGP 23996, were detected in the pertussis toxin-treated membranes. These results are most consistent with pertussis toxin uncoupling the inhibitory G proteins from the somatostatin receptor thereby converting the receptor from a mixed population of high and low affinity sites to only low affinity receptors.

  9. Functional Characteristics of Multipotent Mesenchymal Stromal Cells from Pituitary Adenomas

    PubMed Central

    Megnis, Kaspars; Mandrika, Ilona; Petrovska, Ramona; Stukens, Janis; Rovite, Vita; Balcere, Inga; Jansone, Laima Sabine; Peculis, Raitis; Pirags, Valdis

    2016-01-01

    Pituitary adenomas are one of the most common endocrine and intracranial neoplasms. Although they are theoretically monoclonal in origin, several studies have shown that they contain different multipotent cell types that are thought to play an important role in tumor initiation, maintenance, and recurrence after therapy. In the present study, we isolated and characterized cell populations from seven pituitary somatotroph, nonhormonal, and lactotroph adenomas. The obtained cells showed characteristics of multipotent mesenchymal stromal cells as observed by cell morphology, cell surface marker CD90, CD105, CD44, and vimentin expression, as well as differentiation to osteogenic and adipogenic lineages. They are capable of growth and passaging under standard laboratory cell culture conditions and do not manifest any hormonal cell characteristics. Multipotent mesenchymal stromal cells are present in pituitary adenomas regardless of their clinical manifestation and show no considerable expression of somatostatin 1–5 and dopamine 2 receptors. Most likely obtained cells are a part of tissue-supportive cells in pituitary adenoma microenvironment. PMID:27340409

  10. Functional Characteristics of Multipotent Mesenchymal Stromal Cells from Pituitary Adenomas.

    PubMed

    Megnis, Kaspars; Mandrika, Ilona; Petrovska, Ramona; Stukens, Janis; Rovite, Vita; Balcere, Inga; Jansone, Laima Sabine; Peculis, Raitis; Pirags, Valdis; Klovins, Janis

    2016-01-01

    Pituitary adenomas are one of the most common endocrine and intracranial neoplasms. Although they are theoretically monoclonal in origin, several studies have shown that they contain different multipotent cell types that are thought to play an important role in tumor initiation, maintenance, and recurrence after therapy. In the present study, we isolated and characterized cell populations from seven pituitary somatotroph, nonhormonal, and lactotroph adenomas. The obtained cells showed characteristics of multipotent mesenchymal stromal cells as observed by cell morphology, cell surface marker CD90, CD105, CD44, and vimentin expression, as well as differentiation to osteogenic and adipogenic lineages. They are capable of growth and passaging under standard laboratory cell culture conditions and do not manifest any hormonal cell characteristics. Multipotent mesenchymal stromal cells are present in pituitary adenomas regardless of their clinical manifestation and show no considerable expression of somatostatin 1-5 and dopamine 2 receptors. Most likely obtained cells are a part of tissue-supportive cells in pituitary adenoma microenvironment. PMID:27340409

  11. The pituitary growth hormone cell in space

    NASA Technical Reports Server (NTRS)

    Hymer, Wesley C.; Grindeland, R.

    1989-01-01

    Growth hormone (GH), produced and secreted from specialized cells in the pituitary gland, controls the metabolism of protein, fat, and carbohydrate. It is also probably involved in the regulation of proper function of bone, muscle and immune systems. The behavior of the GH cell system was studied by flying either isolated pituitary cells or live rats. In the latter case, pituitary GH cells are prepared on return to earth and then either transplanted into hypophysectomized rats or placed into cell culture so that function of GH cells in-vivo vs. in-vitro can be compared. The results from three flights to date (STS-8, 1983; SL-3, 1985; Cosmos 1887, 1987) established that the ability of GH cells to release hormone, on return to earth, is compromised. The mechanism(s) responsible for this attenuation response is unknown. However, the data are sufficiently positive to indicate that the nature of the secretory defect resides directly within the GH cells.

  12. Deregulation of miR-183 and KIAA0101 in Aggressive and Malignant Pituitary Tumors

    PubMed Central

    Roche, Magali; Wierinckx, Anne; Croze, Séverine; Rey, Catherine; Legras-Lachuer, Catherine; Morel, Anne-Pierre; Fusco, Alfredo; Raverot, Gérald; Trouillas, Jacqueline; Lachuer, Joel

    2015-01-01

    Changes in microRNAs (miRNAs) expression in many types of cancer suggest that they may be involved in crucial steps during tumor progression. Indeed, miRNAs deregulation has been described in pituitary tumorigenesis, but few studies have described their role in pituitary tumor progression toward aggressiveness and malignancy. To assess the role of miRNAs within the hierarchical cascade of events in prolactin (PRL) tumors during progression, we used an integrative genomic approach to associate clinical–pathological features, global miRNA expression, and transcriptomic profiles of the same human tumors. We describe the specific down-regulation of one principal miRNA, miR-183, in the 8 aggressive (A, grade 2b) compared to the 18 non-aggressive (NA, grades 1a, 2a) PRL tumors. We demonstrate that it acts as an anti-proliferative gene by directly targeting KIAA0101, which is involved in cell cycle activation and inhibition of p53–p21-mediated cell cycle arrest. Moreover, we show that miR-183 and KIAA0101 expression significantly correlate with the main markers of pituitary tumors aggressiveness, Ki-67 and p53. These results confirm the activation of proliferation in aggressive and malignant PRL tumors compared to non-aggressive ones. Importantly, these data also demonstrate the ability of such an integrative genomic strategy, applied in the same human tumors, to identify the molecular mechanisms responsible for tumoral progression even from a small cohort of patients. PMID:26322309

  13. Different functions of QTL for estrogen-dependent tumor growth of the rat pituitary.

    PubMed

    Wendell, D L; Daun, S B; Stratton, M B; Gorski, J

    2000-10-01

    Estrogen treatment to rats of the Fischer 344 (F344) strain induces growth of pituitary tumors that exhibit accelerated cell proliferation, breakdown of basement membrane, and formation of hemorrhagic lakes. Estrogen-dependent pituitary growth is due to variation in a group of quantitative trait loci (QTL), called Edpm for estrogen-dependent pituitary mass, that we previously identified in an F(2) intercross of F344 and the tumor-resistant Brown Norway strain. We previously identified 5 QTL, and microsatellite markers developed since our earlier work have allowed us to scan new chromosomal regions, resulting in two new QTL for estrogen-dependent pituitary mass: Edpm9-2 and a possible QTL on the X Chromosome (Chr). Here we report evidence that these QTL differ from each other in how they affect growth. To examine the effect of the Edpm QTL on biochemical components of tumor growth, we tested their effects in 138 progeny of a backcross to the F344 strain which were given a 10-week chronic estrogen treatment. Hemoglobin/DNA ratio (a measure of blood volume relative to cell number) and total pituitary DNA (a measure of cell number) correlated only weakly, and very large pituitaries were observed which had a low hemoglobin/DNA ratio resembling a normal gland. Through QTL mapping, we found that Edpm2-1, Edpm3, Edpm5, and Edpm9-2 all had significant effects on pituitary mass, but Edpm2-1 and Edpm9-2 primarily affected DNA content, Edpm5 primarily affected hemoglobin/DNA ratio, and Edpm3 affected all traits equally. PMID:11003699

  14. Muscarinic cholinergic ligand binding to intact mouse pituitary tumor cells (AtT-20/D16-16) coupling with two biochemical effectors: adenylate cyclase and phosphatidylinositol turnover.

    PubMed

    Akiyama, K; Vickroy, T W; Watson, M; Roeske, W R; Reisine, T D; Smith, T L; Yamamura, H I

    1986-03-01

    (-)-[3H]Quinuclidinyl benzilate (QNB) binding to muscarinic receptors on intact mouse pituitary tumor cells (AtT-20/D16-16) was characterized in an attempt to correlate radioligand binding properties with receptor-coupled biochemical responses. Performing rinse time studies for 2 hr produced a remarkably improved ratio of specific/total (+)-[3H]QNB binding (85%). Kinetic experiments yielded association (k+1) and dissociation (k-1) rate constants of 2.2 X 10(8) M-1 min-1 and 6.8 X 10(-3) min-1, respectively. Receptor occupancy curves demonstrated a uniform population of specific, saturable (-)-[3H]QNB binding sites with a Hill coefficient equal to 1.0 and an apparent dissociation constant (Kd) equal to 34 pM under our conditions. Stereoselectivity was observed with the enantiomers (dexetimide and levetimide) of benzetimide (a factor of 4300). Concentrations of carbachol that produced a half-maximal inhibition of cyclic AMP formation and a concentration of carbachol for producing half-maximal stimulation of phosphatidylinositol turnover in the intact cells were 0.45 and 170 microM, respectively. Schild analysis revealed that pirenzepine, a nonclassical muscarinic antagonist, had a 40-fold greater affinity for reversing carbachol-stimulated phosphatidylinositol turnover (inhibition constant or Ki = 7 nM), compared to its antagonism of the carbachol-mediated inhibition of isoproterenol-stimulated cyclic AMP formation (Ki = 280 nM). Interestingly, pirenzepine inhibited (-)-[3H]QNB binding with a Ki value of 72 nM. In contrast, atropine was nearly equipotent (Ki = 0.3-0.5 nM) in binding studies and in both effector systems. PMID:3005550

  15. Hedgehog signaling activation induces stem cell proliferation and hormone release in the adult pituitary gland.

    PubMed

    Pyczek, Joanna; Buslei, Rolf; Schult, David; Hölsken, Annett; Buchfelder, Michael; Heß, Ina; Hahn, Heidi; Uhmann, Anja

    2016-01-01

    Hedgehog (HH) signaling is known to be essential during the embryonal development of the pituitary gland but the knowledge about its role in the adult pituitary and in associated tumors is sparse. In this report we investigated the effect of excess Hh signaling activation in murine pituitary explants and analyzed the HH signaling status of human adenopituitary lobes and a large cohort of pituitary adenomas. Our data show that excess Hh signaling led to increased proliferation of Sox2(+) and Sox9(+) adult pituitary stem cells and to elevated expression levels of adrenocorticotropic hormone (Acth), growth hormone (Gh) and prolactin (Prl) in the adult gland. Inhibition of the pathway by cyclopamine reversed these effects indicating that active Hh signaling positively regulates proliferative processes of adult pituitary stem cells and hormone production in the anterior pituitary. Since hormone producing cells of the adenohypophysis as well as ACTH-, GH- and PRL-immunopositive adenomas express SHH and its target GLI1, we furthermore propose that excess HH signaling is involved in the development/maintenance of hormone-producing pituitary adenomas. These findings advance the understanding of physiological hormone regulation and may open new treatment options for pituitary tumors. PMID:27109116

  16. Hedgehog signaling activation induces stem cell proliferation and hormone release in the adult pituitary gland

    PubMed Central

    Pyczek, Joanna; Buslei, Rolf; Schult, David; Hölsken, Annett; Buchfelder, Michael; Heß, Ina; Hahn, Heidi; Uhmann, Anja

    2016-01-01

    Hedgehog (HH) signaling is known to be essential during the embryonal development of the pituitary gland but the knowledge about its role in the adult pituitary and in associated tumors is sparse. In this report we investigated the effect of excess Hh signaling activation in murine pituitary explants and analyzed the HH signaling status of human adenopituitary lobes and a large cohort of pituitary adenomas. Our data show that excess Hh signaling led to increased proliferation of Sox2+ and Sox9+ adult pituitary stem cells and to elevated expression levels of adrenocorticotropic hormone (Acth), growth hormone (Gh) and prolactin (Prl) in the adult gland. Inhibition of the pathway by cyclopamine reversed these effects indicating that active Hh signaling positively regulates proliferative processes of adult pituitary stem cells and hormone production in the anterior pituitary. Since hormone producing cells of the adenohypophysis as well as ACTH-, GH- and PRL-immunopositive adenomas express SHH and its target GLI1, we furthermore propose that excess HH signaling is involved in the development/maintenance of hormone-producing pituitary adenomas. These findings advance the understanding of physiological hormone regulation and may open new treatment options for pituitary tumors. PMID:27109116

  17. Disulfiram sensitizes pituitary adenoma cells to temozolomide by regulating O6-methylguanine-DNA methyltransferase expression.

    PubMed

    Zhao, Yachao; Xiao, Zheng; Chen, Wenna; Yang, Jinsheng; Li, Tao; Fan, Bo

    2015-08-01

    O6-methylguanine-DNA methyltransferase (MGMT) activity is responsible for temozolomide (TMZ) resistance in patients harboring aggressive pituitary adenomas. Recently, disulfiram (DSF) has been shown to induce the loss of MGMT protein and increase TMZ efficacy in glioblastoma cells, while CD133+ nestin+ cells isolated from the cell population have been implicated as pituitary adenoma stem-like cells. However, whether DSF is able to potentiate the cytotoxic effects of TMZ on human pituitary adenoma cells has not been investigated to date. In the present study, CD133+ nestin+ phenotype cells were isolated from primary cultured human pituitary adenoma cells using microbeads. It was found that DSF reduced MGMT protein expression and sensitized human pituitary adenoma cells and stem-like cells to TMZ in vitro, while the proteasome inhibitor PS-341 abrogated the inhibitory effect of DSF on MGMT in vitro. The sensitizing effect of DSF was also verified in primary cultured human pituitary adenoma cells in vivo. The results of the present study suggested that DSF can increase the efficacy of the anti-tumor effect of TMZ on human pituitary adenoma cells and CD133+ nestin+ stem like cells via the ubiquitin-proteasomal MGMT protein elimination route. DSF combined with TMZ may be an effective therapeutic strategy against aggressive pituitary adenomas. PMID:25937029

  18. NG2 targets tumorigenic Rb inactivation in Pit1-lineage pituitary cells.

    PubMed

    Tateno, Toru; Nakano-Tateno, Tae; Ezzat, Shereen; Asa, Sylvia L

    2016-05-01

    The proteoglycan neuron-glial antigen 2 (NG2) is expressed by oligodendrocyte progenitors, pericytes, and some cancerous cells where it is implicated in tumor development. We examined mice with NG2-driven pRb inactivation. Unexpectedly, NG2-Cre:pRb(flox/flox) mice developed pituitary tumors with high penetrance. Adenohypophysial neoplasms developed initially as multifocal lesions; by 1 year, large tumors showed brain invasion. Immunohistochemistry identified these as Pit1-lineage neoplasms, with variable immunoreactivity for growth hormone, prolactin, thyrotropin, and α-subunit of glycoprotein hormones. Other than modest hyperprolactinemia, circulating hormone levels were not elevated. To determine the role of NG2 in the pituitary, we investigated NG2 expression. Immunoreactivity was identified in anterior and posterior lobes but not in the intermediate lobe of the mouse pituitary; in the adenohypophysis, folliculostellate cells had the strongest NG2 immunoreactivity but showed no proliferation in response to Rb inactivation. Pit1-positive adenohypophysial cells were positive for NG2, but corticotroph and gonadotroph cells were negative. RT-PCR revealed NG2 expression in normal human pituitary and human pituitary tumors; immunohistochemistry localized NG2 in nontumorous human adenohypophysis with strongest positivity in folliculostellate cells, and in tumors of all types except corticotrophs. Functional studies in GH4 mammosomatotrophs showed that NG2 increases prolactin (PRL), reduces growth hormone (GH) expression, and enhances cell adhesion without influencing proliferation. In conclusion, NG2-driven pRb inactivation results in pituitary tumors that mimic endocrinologically inactive Pit1-lineage human pituitary tumors. This model identifies a role for NG2 in pituitary cell-type-specific functions and unmasks a protective role from Rb inactivation in folliculostellate cells; it can be used for further research, including preclinical testing of novel therapies

  19. Interleukin-2 and interleukin-2 receptor expression in human corticotrophic adenoma and murine pituitary cell cultures.

    PubMed Central

    Arzt, E; Stelzer, G; Renner, U; Lange, M; Müller, O A; Stalla, G K

    1992-01-01

    The production of IL-1 and IL-6 by pituitary cells has recently been demonstrated. In this study we investigated the expression of IL-2 and its receptor (IL-2R) by pituitary cells of different species. In Northern blots, a single hybridizing band of 1 kb, identical to that in normal stimulated lymphocytes, was obtained with specific IL-2 probes. In the mouse AT-20 pituitary tumor cell line, IL-2 mRNA expression was detected after stimulation with corticotropin-releasing hormone or phorbol myristate acetate. In human corticotrophic adenoma cells, basal IL-2 mRNA expression as well as IL-2 secretion were further stimulated by phorbol myristate acetate. Both adenoma and AtT-20 cells showed detectable amounts of IL-2R mRNA and by immunofluorescence, IL-2R membrane expression. In addition, dual immunofluorescence studies in rat anterior pituitary cells demonstrated colocalization of IL-2R with ACTH-positive cells and other cell types expressing the receptor. In addition to the action of lymphocyte-produced IL-2, this cytokine may have a paracrine or autocrine regulatory role within the pituitary. It remains to be established whether IL-2 production occurs in the normal pituitary or is intrinsic to the process of tumor development of these cells. IL-2 may be involved in the growth control of pituitary cells. Images PMID:1331177

  20. Pituitary Tumors in Childhood: an update in their diagnosis, treatment and molecular genetics

    PubMed Central

    Keil, Margaret F.; Stratakis, Constantine A.

    2009-01-01

    Pituitary tumors are rare in childhood and adolescence, with a reported prevalence of up to 1 per million children. Only 2 - 6% of surgically treated pituitary tumors occur in children. Although pituitary tumors in children are almost never malignant and hormonal secretion is rare, these tumors may result in significant morbidity. Tumors within the pituitary fossa are of two types mainly, craniopharyngiomas and adenomas; craniopharyngiomas cause symptoms by compressing normal pituitary, causing hormonal deficiencies and producing mass effects on surrounding tissues and the brain; adenomas produce a variety of hormonal conditions such as hyperprolactinemia, Cushing disease and acromegaly or gigantism. Little is known about the genetic causes of sporadic lesions, which comprise the majority of pituitary tumors, but in children, more frequently than in adults, pituitary tumors may be a manifestation of genetic conditions such as multiple endocrine neoplasia type 1 (MEN 1), Carney complex, familial isolated pituitary adenoma (FIPA), and McCune-Albright syndrome. The study of pituitary tumorigenesis in the context of these genetic syndromes has advanced our knowledge of the molecular basis of pituitary tumors and may lead to new therapeutic developments. PMID:18416659

  1. Clinicopathological prognostic and theranostic markers in pituitary tumors.

    PubMed

    Vasiljevic, Alexandre; Jouanneau, Emmanuel; Trouillas, Jacqueline; Raverot, Gérald

    2016-09-01

    More than just the confirmation of an endocrinological diagnosis, the pathological analysis of pituitary endocrine tumors may contribute to bring crucial information in prognosis as well as useful insights in therapeutic management. Taken individually, parameters such as histopathological subtyping, Ki-67-labelling or P53 immunoexpression cannot accurately predict the outcome of patients affected by such tumors. Conversely, "mixed" classification integrating invasion assessment by imaging to histopathological diagnosis may give critical prognostic information and help the clinician in identifying those aggressive tumors that will require a careful follow-up and a more vigorous postoperative treatment. Analysis of theranostic factors such as O6-methylguanine-DNA methyl-transferase or somatostatin receptor expression may guide the choice of postoperative treatment. PMID:26940458

  2. Dopamine receptor expression and function in corticotroph pituitary tumors.

    PubMed

    Pivonello, Rosario; Ferone, Diego; de Herder, Wouter W; Kros, Johan M; De Caro, Maria Laura Del Basso; Arvigo, Marica; Annunziato, Lucio; Lombardi, Gaetano; Colao, Annamaria; Hofland, Leo J; Lamberts, Steven W J

    2004-05-01

    The role of dopamine agonist treatment in corticotroph pituitary tumors is controversial. The aim of this study was to evaluate D(2) receptor expression in 20 corticotroph pituitary tumors and to correlate it to the in vitro effect of dopamine agonists on ACTH secretion and the in vivo effect of short-term cabergoline treatment on cortisol secretion. D(2) expression was evaluated by receptor-ligand binding, immunohistochemistry, and RT-PCR. A 50% or more decrease in daily urinary cortisol levels was considered a significant clinical response. At receptor-ligand binding, specific binding of [(125)I]epidepride was found in 80% of cases. At immunohistochemistry, specific D(2) immunostaining was found in 75% of cases. D(2) expression was found in 83.3% of cases (D(2long) in 40%, D(2short) in 20%, and both in 40%) by RT-PCR. Significant in vitro inhibition of ACTH secretion was found in 100% of D(2)-positive cases, but not in 100% of D(2)-negative cases by either bromocriptine or cabergoline. A significant in vivo inhibition of cortisol secretion after 3-month cabergoline treatment was found in 60%, although a normalization of cortisol secretion was found in 40% of cases. All cabergoline-responsive cases were associated with D(2) expression, whereas all noncabergoline-responsive cases but one were not associated with D(2) expression. In conclusion, functional D(2) receptors were expressed in approximately 80% of corticotroph pituitary tumors. The effectiveness of cabergoline in normalizing cortisol secretion in 40% of cases supports its therapeutic use in the management of Cushing's disease. PMID:15126577

  3. Pulsatile glycoprotein hormone secretion in glycoprotein-producing pituitary tumors.

    PubMed

    Samuels, M H; Henry, P; Kleinschmidt-Demasters, B K; Lillehei, K; Ridgway, E C

    1991-12-01

    To study patterns of hormone production and secretion in glycoprotein-producing pituitary tumors, 12 patients with such tumors underwent the following studies. Preoperatively, all patients had serum TSH, LH, FSH, and alpha-subunit levels measured every 15 min for 24 h. Hormone pulses were located by cluster analysis, and pulse parameters were compared to those in healthy young men, healthy young women, healthy postmenopausal women, and subjects with primary hypothyroidism. After surgery, immunocytochemistry for the four glycoproteins was performed on all tumors, and Northern blot analysis was performed in six tumors with probes for the four subunits. By immunocytochemistry, 42% of the tumors were positive for TSH beta, 83% for LH beta, 75% for FSH beta, and 92% for alpha-subunit. Preoperative serum hormone levels varied widely between patients and were not well correlated with the intensity of immunocytochemical staining. Northern blot analysis did not appear to be as sensitive as immunocytochemistry for detection of the glycoproteins. All patients had pulsatile glycoprotein secretion, with pulses of normal frequency but varied amplitude. These results suggest that in patients with glycoprotein tumors, hormone pulses may be an integral part of autonomous secretion, or that hypothalamic control is involved in glycoprotein secretion and, perhaps, in the pathogenesis of these tumors. PMID:1955510

  4. Histopathological and immunohistochemical characterization of spontaneous pituitary tumors in dwarfs derived from Wistar Hannover GALAS rats.

    PubMed

    Kokoshima, Hiroko; Yamada, Naoaki; Doi, Takuya; Tsuchitani, Minoru; Yamate, Jyoji

    2016-01-01

    Histopathological and immunohistochemical characteristics of spontaneous pituitary adenomas found in dwarfs derived from Wistar Hanover GALAS are being described for the first time. The adenomas were seen in 5 males aged 48 weeks or older and in 11 females aged 34 weeks or older. Immunohistochemically, 13 cases without post-mortem changes could be evaluated; 4 Thyroid stimulating hormone (TSH)-containing adenomas, 2 TSH- and prolactin (PRL)-containing adenomas, 1 PRL-containing adenoma and 6 all-negative adenomas that did not react to any of the examined anti-hormone antibodies. The most common type were TSH-containing pituitary adenomas (a total of 6 cases; 46%) which occurred exclusively in females; the tumors consisted mainly of basophilic or amphophilic cells with bizarre nuclei and neoplastic cells and were positive for TSH in varying degrees. The TSH-containing pituitary adenomas, a characteristic of this mutant rat, could be induced by genetically-controlled hypothyroidism in dwarf rats, with higher sensitivity to possible disturbance of the pituitary-thyroid axis in females. PMID:26597119

  5. Single or group housing altered hormonal physiology and affected pituitary and interstitial cell kinetics

    EPA Science Inventory

    A significant negative correlation between testicular interstitial cell tumors and pituitary tumors in control male F344 rats has been reported associated with the number of animals per cage. Change in numbers of animals per cage may cause stress and increased serum corticosteroi...

  6. Electrophoretic separation of kidney and pituitary cells on STS-8

    NASA Technical Reports Server (NTRS)

    Morrison, D. R.; Nachtwey, D. S.; Barlow, G. H.; Cleveland, C.; Lanham, J. W.; Farrington, M. A.; Hatfield, J. M.; Hymer, W. C.; Grindeland, R.; Lewis, M. L.

    1984-01-01

    Specific secretory cells were separated from suspensions of cultured primary human embryonic cells and rat pituitary cells in microgravity conditions, with an objective of isolating the subfractions of kidney cells that produce the largest amount of urakinase, and the subfractions of rat pituitary cells that secrete growth hormones (GH), prolactin (PRL), and other hormones. It is inferred from the experimental observations that the surface charge distributions of the GH-containing cells differ from those of the PRL-containing cells, which is explained by the presence of secretory products on the surface of pituitary cells. For kidney cells, the electrophoretic mobility distributions in flight experiments were spread more than the ground controls.

  7. Gonadotropin-releasing hormone receptor mRNA expression by human pituitary tumors in vitro.

    PubMed Central

    Alexander, J M; Klibanski, A

    1994-01-01

    An important question in the pathogenesis and regulation of human gonadotroph adenomas is whether heterogeneous gonadotropin responses to gonadotropin-releasing hormone (GnRH) are due to dysregulation of GnRH receptor biosynthesis and/or cell-signaling pathways. We investigated gonadotropin responsiveness to pulsatile GnRH in 13 gonadotroph adenomas. All tumors had evidence of follicle-stimulating hormone (FSH) beta and alpha subunit biosynthesis using reverse transcriptase/polymerase chain reaction (RTPCR) techniques. Four tumors significantly increased gonadotropin and/or free subunit secretion during pulsatile 10(-8) M GnRH administration. The GnRH antagonist Antide (10(-6) to 10(-8) M) blocked secretory increases in all GnRH-responsive tumors. Gonadotropin and/or free subunit secretion increased after 60 mM KCl, confirming that GnRH nonresponsiveness was not due to intracellular gonadotropin depletion. We hypothesized that GnRH nonresponsiveness in these tumors may be due to GnRH receptor (GnRH-Rc) biosynthetic defects. RTPCR analyses detected GnRH-Rc transcripts only in responsive tumors and normal human pituitary. This is the first demonstration of a cell-surface receptor biosynthetic defect in human pituitary tumors. We conclude (a) one third of gonadotroph tumors respond to pulsatile GnRH in vitro, (b) GnRH-Rc mRNA is detected in human gonadotroph adenomas and predicts GnRH responsiveness, and (c) GnRH-Rc biosynthetic defects may underlie GnRH nonresponsiveness in gonadotroph tumors. Images PMID:8200967

  8. MALDI mass spectrometry imaging analysis of pituitary adenomas for near-real-time tumor delineation

    PubMed Central

    Calligaris, David; Feldman, Daniel R.; Norton, Isaiah; Olubiyi, Olutayo; Changelian, Armen N.; Machaidze, Revaz; Vestal, Matthew L.; Laws, Edward R.; Dunn, Ian F.; Santagata, Sandro; Agar, Nathalie Y. R.

    2015-01-01

    We present a proof of concept study designed to support the clinical development of mass spectrometry imaging (MSI) for the detection of pituitary tumors during surgery. We analyzed by matrix-assisted laser desorption/ionization (MALDI) MSI six nonpathological (NP) human pituitary glands and 45 hormone secreting and nonsecreting (NS) human pituitary adenomas. We show that the distribution of pituitary hormones such as prolactin (PRL), growth hormone (GH), adrenocorticotropic hormone (ACTH), and thyroid stimulating hormone (TSH) in both normal and tumor tissues can be assessed by using this approach. The presence of most of the pituitary hormones was confirmed by using MS/MS and pseudo-MS/MS methods, and subtyping of pituitary adenomas was performed by using principal component analysis (PCA) and support vector machine (SVM). Our proof of concept study demonstrates that MALDI MSI could be used to directly detect excessive hormonal production from functional pituitary adenomas and generally classify pituitary adenomas by using statistical and machine learning analyses. The tissue characterization can be completed in fewer than 30 min and could therefore be applied for the near-real-time detection and delineation of pituitary tumors for intraoperative surgical decision-making. PMID:26216958

  9. MALDI mass spectrometry imaging analysis of pituitary adenomas for near-real-time tumor delineation.

    PubMed

    Calligaris, David; Feldman, Daniel R; Norton, Isaiah; Olubiyi, Olutayo; Changelian, Armen N; Machaidze, Revaz; Vestal, Matthew L; Laws, Edward R; Dunn, Ian F; Santagata, Sandro; Agar, Nathalie Y R

    2015-08-11

    We present a proof of concept study designed to support the clinical development of mass spectrometry imaging (MSI) for the detection of pituitary tumors during surgery. We analyzed by matrix-assisted laser desorption/ionization (MALDI) MSI six nonpathological (NP) human pituitary glands and 45 hormone secreting and nonsecreting (NS) human pituitary adenomas. We show that the distribution of pituitary hormones such as prolactin (PRL), growth hormone (GH), adrenocorticotropic hormone (ACTH), and thyroid stimulating hormone (TSH) in both normal and tumor tissues can be assessed by using this approach. The presence of most of the pituitary hormones was confirmed by using MS/MS and pseudo-MS/MS methods, and subtyping of pituitary adenomas was performed by using principal component analysis (PCA) and support vector machine (SVM). Our proof of concept study demonstrates that MALDI MSI could be used to directly detect excessive hormonal production from functional pituitary adenomas and generally classify pituitary adenomas by using statistical and machine learning analyses. The tissue characterization can be completed in fewer than 30 min and could therefore be applied for the near-real-time detection and delineation of pituitary tumors for intraoperative surgical decision-making. PMID:26216958

  10. Molecular Mechanisms Underlying Pituitary Pathogenesis.

    PubMed

    Sapochnik, Melanie; Nieto, Leandro Eduardo; Fuertes, Mariana; Arzt, Eduardo

    2016-04-01

    During the last years, progress has been made on the identification of mechanisms involved in anterior pituitary cell transformation and tumorigenesis. Oncogene activation, tumor suppressor gene inactivation, epigenetic changes, and microRNAs deregulation contribute to the initiation of pituitary tumors. Despite the high prevalence of pituitary adenomas, they are mostly benign, indicating that intrinsic mechanisms may regulate pituitary cell expansion. Senescence is characterized by an irreversible cell cycle arrest and represents an important protective mechanism against malignancy. Pituitary tumor transforming gene (PTTG) is an oncogene involved in early stages of pituitary tumor development, and also triggers a senescence response by activating DNA-damage signaling pathway. Cytokines, as well as many other factors, play an important role in pituitary physiology, affecting not only cell proliferation but also hormone secretion. Special interest is focused on interleukin-6 (IL-6) because its dual function of stimulating pituitary tumor cell growth but inhibiting normal pituitary cells proliferation. It has been demonstrated that IL-6 has a key role in promoting and maintenance of the senescence program in tumors. Senescence, triggered by PTTG activation and mediated by IL-6, may be a mechanism for explaining the benign nature of pituitary tumors. PMID:26718581

  11. The role of proto-oncogene GLI1 in pituitary adenoma formation and cell survival regulation.

    PubMed

    Lampichler, Katharina; Ferrer, Patricio; Vila, Greisa; Lutz, Mirjam I; Wolf, Florian; Knosp, Engelbert; Wagner, Ludwig; Luger, Anton; Baumgartner-Parzer, Sabina

    2015-10-01

    The Hedgehog (Hh) pathway is an important regulator of early tissue patterning and stem cell propagation. It was found to be aberrantly activated in numerous types of human cancer and might be relevant in cancer stem cells. The identification of adult stem cells in the pituitary raised the question if tumor-initiating cells and Hh signaling are involved in pituitary adenoma formation. The present study aimed at the evaluation of Hh signaling in relation to stem cell and cell cycle markers in 30 human pituitary adenomas and in cultured murine adenoma cells. Therefore, expression levels of components of the Hh pathway, stem cell marker SOX2, cell cycle regulator tumor-protein 53 (TP53), proliferation marker Ki67 (MKI67) and superoxide dismutase 1 (SOD1) were evaluated in 30 human pituitary adenomas in comparison to control tissue. Modulation of cell function and target gene expression by the inhibition and activation of the Hh pathway were studied in murine adenoma cells. We show that transcription factor glioma-associated oncogene 1 (GLI1) is overexpressed in 87% of all pituitary adenomas. The expression of GLI1 significantly correlated with that of SOX2, TP53, MKI67 and SOD1. Inhibition of GLI1 resulted in the downregulation of the above genes and severe cell death in mouse adenoma cells. On the other hand, activation of the Hh pathway increased cell viability and target gene expression. In conclusion, our findings point toward an alternative, ligand-independent Hh pathway activation with GLI1 playing a major role in the cell survival of pituitary adenoma cells. PMID:26219678

  12. Separation of cells from the rat anterior pituitary gland

    NASA Technical Reports Server (NTRS)

    Hymer, W. C.; Hatfield, J. Michael

    1984-01-01

    Data concerned with analyzing the cellular organization of the rat anterior pituitary gland are examined. The preparation of the cell suspensions and the methods used to separate pituitary cell types are described. Particular emphasis is given to velocity sedimentation at unit gravity, density gradient centrifugation, affinity methods, fluorescence activated cell sorting, and density gradient and continuous-flow electrophoresis. The difficulties encountered when attempting to compare data from different pituitary cell separation studies are discussed, and results from various experiments are presented. The functional capabilities of the separated cell populations can be tested in various culture systems.

  13. Purification and cultivation of human pituitary growth hormone secreting cells

    NASA Technical Reports Server (NTRS)

    Hymer, W. C.

    1984-01-01

    A multiphase study was conducted to examine the properties of growth hormone cells. Topics investigated included: (1) to determine if growth hormone (GH) cells contained within the rat pituitary gland can be separated from the other hormone producing cell types by continuous flow electrophoresis (CFE); (2) to determine what role, if any, gravity plays in the electrophoretic separation of GH cells; (3) to compare in vitro GH release from rat pituitary cells previously exposed to microgravity conditions vs release from cells not exposed to microgravity; (4) to determine if the frequency of different hormone producing pituitary cell types contained in cell suspensions can be quantitated by flow cytometry; and (5) to determine if GH contained within the human post mortem pituitary gland can be purified by CFE. Specific experimental procedures and results are included.

  14. Purification and cultivation of human pituitary growth hormone secreting cells

    NASA Technical Reports Server (NTRS)

    Hymer, W. C.

    1978-01-01

    The maintainance of actively secreting human pituitary growth hormone cells (somatotrophs) in vitro was studied. The primary approach was the testing of agents which may be expected to increase the release of the human growth hormone (hGH). A procedure for tissue procurement is described along with the methodologies used to dissociate human pituitary tissue (obtained either at autopsy or surgery) into single cell suspensions. The validity of the Biogel cell column perfusion system for studying the dynamics of GH release was developed and documented using a rat pituitary cell system.

  15. Multicenter study on adult growth hormone level in postoperative pituitary tumor patients.

    PubMed

    Cheng, Jing-min; Gu, Jian-wen; Kuang, Yong-qin; Ma, Yuan; Xia, Xun; Yang, Tao; Lu, Min; He, Wei-qi; Sun, Zhi-yong; Zhang, Yan-chao

    2015-03-01

    The objective of this study is to observe the adult growth hormone level in postoperative pituitary tumor patients of multi-centers, and explore the change of hypophyseal hormones in postoperative pituitary tumor patients. Sixty patients with pituitary tumor admitted during March, 2011-March, 2012 were selected. Postoperative hypophyseal hormone deficiency and the change of preoperative, intraoperative, and postoperative growth hormone levels were recorded. Growth hormone hypofunction was the most common hormonal hypofunction, which took up to 85.0 %. Adrenocortical hormone hypofunction was next to it and accounted for 58.33 %. GH + ACTH + TSH + Gn deficiency was the most common in postoperative hormone deficiency, which took up to 40.00 %, and GH + ACTH + TSH + Gn + AVP and GH deficiencies were next to it and accounted for 23.33 and 16.67 %, respectively. The hormone levels in patients after total pituitary tumor resection were significantly lower than those after partial pituitary tumor resection, and the difference was statistically significant; growth hormone and serum prolactin levels after surgery in two groups were decreased, and the difference was statistically significant. The incidence rate of growth hormone deficiency in postoperative pituitary tumor patients is high, which is usually complicated with deficiency of various hypophyseal hormones. In clinical, we should pay attention to the levels of the hypopnyseal hormones, and take timely measures to avoid postoperative complications. PMID:25403160

  16. Pituitary Stone or Calcified Pituitary Tumor? Three Cases and Literature Review

    PubMed Central

    Chentli, Farida; Safer-Tabi, Amel

    2015-01-01

    Introduction: Pituitary stone or pituitary calculus is a scientific enigma characterized by a large calcification in the pituitary sella. It can be discovered incidentally or in a patient with endocrine and/or neurological problems. Its mechanism is not understood. In this article, we described three patients harboring a large pituitary calcification. Case Presentation: The first case was observed in a 27-year-old woman who consulted for secondary amenorrhea. The second case concerned a woman who consulted for infertility, and the third one was observed in an 11-year and nine-month-old girl who was sent to our department for short stature. Clinical examination was normal in both adults. The pediatric case had dwarfism with lack of pubertal development. Hormonal assessment showed hyperprolactinemia in both women and thyrotroph and somatotroph deficits in the child. Radiologic exploration discovered pituitary calcifications measuring 10, 11, and 45 mm without any cystic or solid mass. Conclusions: Radiological findings pleaded for a pituitary stone, but calcified adenomas in women, and calcified craniopharyngioma in the pediatric case could not be excluded, as our three patients were not operated on. PMID:26401144

  17. Pituitary abscess.

    PubMed

    Rudwan, M A

    1977-05-28

    Three cases of pituitary abscess are presented. The history of recurrent attacks of aseptic meningitis, together with radiological and clinical features suggestive of pituitary tumor, appear to form a fairly typical picture of the condition. Long follow-up was possible in two of the cases. There are no radiological features which distinguish the lesion from pituitary tumor, hence the importance of recognizing the significance of such a clinical presentation with radiological evidence of sellar enlargement. Pituitary abscesses seem to occur in preexisting pituitary tumors. The possible relationship with pituitary infarction is discussed. PMID:865667

  18. Metastatic Mantle Cell Lymphoma to the Pituitary Gland: Case Report and Literature Review

    PubMed Central

    Wang, Arthur; Carberry, Nathan; Solli, Elena; Kleinman, George; Tandon, Adesh

    2016-01-01

    We present an unusual case of a metastatic mantle cell lymphoma (MCL) to the pituitary gland. The patient had a known history of MCL for which she previously received chemotherapy. She presented with new-onset diplopia and confusion, and reported a history of progressive vision blurriness associated with headache, nausea, and vomiting. MRI of the brain showed an enhancing lesion within the sella turcica involving the cavernous sinuses bilaterally, extending into Meckel's cave on the left, and abutting the optic nerves bilaterally. Following surgical excision, histopathology revealed the tumor to be a MCL. Metastatic pituitary tumors are rare and have been estimated to make up 1% of tumors discovered in the sellar region. The two most common secondary metastatic lesions to the sella are breast and lung carcinoma followed by prostate, renal cell, and gastrointestinal carcinoma. Metastatic lymphoma to the pituitary gland is especially rare and is estimated to constitute 0.5% of all metastatic tumors to the sella turcica. To our knowledge, this is the first reported case of MCL metastasizing to the pituitary gland. PMID:26933415

  19. Inhibitory role of ERβ on anterior pituitary cell proliferation by controlling the expression of proteins related to cell cycle progression.

    PubMed

    Pérez, Pablo A; Petiti, Juan P; Wagner, Ignacio A; Sabatino, Maria E; Sasso, Corina V; De Paul, Ana L; Torres, Alicia I; Gutiérrez, Silvina

    2015-11-01

    Considering that the role of ERβ in the growth of pituitary cells is not well known, the aim of this work was to determine the expression of ERβ in normal and tumoral cells and to investigate its implications in the proliferative control of this endocrine gland, by analyzing the participation of cyclin D1, Cdk4 and p21. Our results showed that the expression of ERβ decreased during pituitary tumoral development induced by chronic E2 stimulation. The 20 ± 1.6% of normal adenohypophyseal cells expressed ERβ, with this protein being reduced in the hyperplastic/adenomatous pituitary: at 20 days the ERβ+ population was 10.7 ± 2.2%, while after 40 and 60 days of treatment an almost complete loss in the ERβ expression was observed (40 d: 1 ± 0.6%; 60 d: 2 ± 0.6%). The ERα/β ratio increased starting from tumors at 40 days, mainly due to the loss of ERβ expression. The cell proliferation was analyzed in normal and hyperplastic pituitary and also in GH3β- and GH3β+ which contained different levels of ERβ expression, and therefore different ERα/β ratios. The over-expression of ERβ inhibited the GH3 cell proliferation and expression of cyclin D1 and ERα. Also, the ERβ activation by its agonist DPN changed the subcellular localization of p21, inducing an increase in the p21 nuclear expression, where it acts as a tumoral suppressor. These results show that ERβ exerts an inhibitory role on pituitary cell proliferation, and that this effect may be partially due to the modulation of some key regulators of the cell cycle, such as cyclin D1 and p21. These data contribute significantly to the understanding of the ER effects in the proliferative control of pituitary gland, specifically related to the ERβ function in the E2 actions on this endocrine gland. PMID:26282612

  20. A GRFa2/Prop1/Stem (GPS) Cell Niche in the Pituitary

    PubMed Central

    Garcia-Lavandeira, Montse; Quereda, Víctor; Flores, Ignacio; Saez, Carmen; Diaz-Rodriguez, Esther; Japon, Miguel A.; Ryan, Aymee K.; Blasco, Maria A.; Dieguez, Carlos; Malumbres, Marcos; Alvarez, Clara V.

    2009-01-01

    Background The adult endocrine pituitary is known to host several hormone-producing cells regulating major physiological processes during life. Some candidates to progenitor/stem cells have been proposed. However, not much is known about pituitary cell renewal throughout life and its homeostatic regulation during specific physiological changes, such as puberty or pregnancy, or in pathological conditions such as tumor development. Principal Findings We have identified in rodents and humans a niche of non-endocrine cells characterized by the expression of GFRa2, a Ret co-receptor for Neurturin. These cells also express b-Catenin and E-cadherin in an oriented manner suggesting a planar polarity organization for the niche. In addition, cells in the niche uniquely express the pituitary-specific transcription factor Prop1, as well as known progenitor/stem markers such as Sox2, Sox9 and Oct4. Half of these GPS (GFRa2/Prop1/Stem) cells express S-100 whereas surrounding elongated cells in contact with GPS cells express Vimentin. GFRa2+-cells form non-endocrine spheroids in culture. These spheroids can be differentiated to hormone-producing cells or neurons outlining the neuroectoderm potential of these progenitors. In vivo, GPSs cells display slow proliferation after birth, retain BrdU label and show long telomeres in its nuclei, indicating progenitor/stem cell properties in vivo. Significance Our results suggest the presence in the adult pituitary of a specific niche of cells characterized by the expression of GFRa2, the pituitary-specific protein Prop1 and stem cell markers. These GPS cells are able to produce different hormone-producing and neuron-like cells and they may therefore contribute to postnatal pituitary homeostasis. Indeed, the relative abundance of GPS numbers is altered in Cdk4-deficient mice, a model of hypopituitarism induced by the lack of this cyclin-dependent kinase. Thus, GPS cells may display functional relevance in the physiological expansion of the

  1. Differential Effects of PI3K and Dual PI3K/mTOR Inhibition in Rat Prolactin-Secreting Pituitary Tumors.

    PubMed

    Chanal, Marie; Chevallier, Pascale; Raverot, Véronique; Fonteneau, Guillaume; Lucia, Kristin; Monteserin Garcia, Jose Luis; Rachwan, Alexa; Jouanneau, Emmanuel; Trouillas, Jacqueline; Honnorat, Jérôme; Auger, Carole; Theodoropoulou, Marily; Raverot, Gérald

    2016-06-01

    Aggressive pituitary tumors are rare but difficult to manage, as there is no effective chemotherapy to restrict their growth and cause their shrinkage. Within these tumors, growth-promoting cascades, like the PI3K/mTOR pathway, appear to be activated. We tested the efficacy of two inhibitors of this pathway, NVP-BKM120 (Buparlisib; pan-PI3K) and NVP-BEZ235 (dual PI3K/mTOR), both in vitro on immortalized pituitary tumor cells (GH3) and on primary cell cultures of human pituitary tumors and in vivo on a rat model of prolactin (PRL) tumors (SMtTW3). In vitro, NVP-BEZ235 had a potent apoptotic and cytostatic effect that was characterized by decreased cyclin D/E and Cdk4/2 protein levels and subsequent accumulation of cells in G1 In vivo, the effect was transient, with a decrease in mitotic index and increase in apoptosis; long-term treatment had no significant inhibitory effect on tumor growth. In contrast, while NVP-BKM120 had little effect in vitro, it dramatically limited tumor growth in vivo Increased Akt phosphorylation observed only in the NVP-BEZ235-treated tumors may explain the differential response to the two inhibitors. Primary cell cultures of human PRL pituitary tumors responded to NVP-BEZ235 with reduced cell viability and decreased hormone secretion, whereas NVP-BKM120 had little effect. Altogether, these results show a potential for PI3K inhibitors in the management of aggressive pituitary tumors. Mol Cancer Ther; 15(6); 1261-70. ©2016 AACR. PMID:26983879

  2. Transcranial excision of massive pituitary tumor with low-energy holmium laser

    NASA Astrophysics Data System (ADS)

    Xiong, Wen-Hao; Luo, Qi-Zhong; Li, Shan-Quan; Li, Xiao-Xiong; Dai, Jun; Zhu, Jing; Zhang, Mei-Jue

    1998-11-01

    From May, 1994 to September, 1996 we have operated on 64 cases of brain tumor with Homium Laser, 18 cases of massive pituitary tumor with low energy laser were included. The result are satisfying. Now, we report it to the congress.

  3. Forces Applied at the Skull Base during Transnasal Endoscopic Transsphenoidal Pituitary Tumor Excision

    PubMed Central

    Bekeny, James R.; Swaney, Philip J.; Webster, Robert J.; Russell, Paul T.; Weaver, Kyle D.

    2013-01-01

    Objectives Our laboratory is developing a surgical robotic system to further improve dexterity and visualization that will allow for broader application of transnasal skull base surgery. To optimize this system, intraoperative force data are required. Using a modified curette, force data were recorded and analyzed during pituitary tumor excision. Design A neurosurgical curette was modified by the addition of a force sensor. The instrument was validated in an in vitro model to measure forces during simulated pituitary tumor excision. Following this, intraoperative force data from three patients during transnasal endoscopic excision of pituitary tumors was obtained. Setting Academic medical center. Main Outcome Measures Forces applied at the skull base during surgical excision of pituitary tumors. Results Average forces applied during in vitro testing ranged from 0.1 to 0.15 N. Average forces recorded during in vivo testing ranged from 0.1 to 0.5 N. Maximal forces occurred with collisions of the bony sella. The average maximal force was 1.61 N. There were no complications related to the use of the modified curette. Conclusions Forces to remove pituitary tumor are small and are similar between patients. The in vitro model presented here is adequate for further testing of a robotic skull base surgery system. PMID:24436934

  4. Expression of Eag1 K+ channel and ErbBs in human pituitary adenomas: cytoskeleton arrangement patterns in cultured cells.

    PubMed

    del Pliego, Margarita González; Aguirre-Benítez, Elsa; Paisano-Cerón, Karina; Valdovinos-Ramírez, Irene; Rangel-Morales, Carlos; Rodríguez-Mata, Verónica; Solano-Agama, Carmen; Martín-Tapia, Dolores; de la Vega, María Teresa; Saldoval-Balanzario, Miguel; Camacho, Javier; Mendoza-Garrido, María Eugenia

    2013-01-01

    Pituitary adenomas can invade surrounded tissue, but the mechanism remains elusive. Ether à go-go-1 (Eag1) potassium channel and epidermal growth factor receptors (ErbB1 and ErbB2) have been associated to invasive phenotypes or poor prognosis in cancer patients. However, cells arrange their cytoskeleton in order to acquire a successful migration pattern. We have studied ErbBs and Eag1 expression, and cytoskeleton arrangements in 11 human pituitary adenomas. Eag1, ErbB1 and ErbB2 expression were studied by immunochemistry in tissue and cultured cells. The cytoskeleton arrangement was analyzed in cultured cells by immunofluorescence. Normal pituitary tissue showed ErbB2 expression and Eag1 only in few cells. However, Eag1 and ErbB2 were expressed in all the tumors analyzed. ErbB1 expression was observed variable and did not show specificity for a tumor characteristic. Cultured cells from micro- and macro-adenomas clinically functional organize their cytoskeleton suggesting a mesenchymal pattern, and a round leucocyte/amoeboid pattern from invasive clinically silent adenoma. Pituitary tumors over-express EGF receptors and the ErbB2 repeated expression suggests is a characteristic of adenomas. Eag 1 was express, in different extent, and could be a therapeutic target. The cytoskeleton arrangements observed suggest that pituitary tumor cells acquire different patterns: mesenchymal, and leucocyte/amoeboid, the last observed in the invasive adenomas. Amoeboid migration pattern has been associated with high invasion capacity. PMID:23413122

  5. Mapping of corticotropic cells in the normal human pituitary.

    PubMed

    Trouillas, J; Guigard, M P; Fonlupt, P; Souchier, C; Girod, C

    1996-05-01

    We accomplished the first mapping of corticotropic cells in the whole human adult pituitary. Corticotropic cells were identified by immunocytochemistry (ICC) and quantified by image analysis on 12 pituitaries obtained from people who had died suddenly. An overall view of each pituitary was given by 15-21 sections (mean 18 sections) at 300-micron intervals on six slides. Each section was systematically treated by indirect immunoperoxidase using an anti-ACTH[17-39] polyclonal antiserum. All the measures were done with a x 6.3 objective lens, each field (0. 5 mm2) being considered as the unit area. The mean pituitary density (surface of labeled cells/total surface) of corticotropic cells (9.5 +/- 3.0% per 0. 5 mm2) is significantly higher in men (11.5 +/- 5.1%) than in women (7.0 +/- 1.3%). This difference is due to an inverse relationship between the corticotropic cell density and the weight of the pituitary, which is higher in women than in men. The mean diameter of corticotropic cells is 14.9 micron and their total number per pituitary is approximately 10(7) cells. We confirmed that the spatial distribution of corticotropic cells is nonuniform: they are mainly distributed in the anteromedian part of the anterior lobe. In addition, our results demonstrated that the inferior part of the pituitary contained three times more corticotropic cells than the superior part (mean density 18.0% vs 6.0%) and the anterior part twice as many as the posterior part (mean density 12.3% vs 6.8%). On the horizontal plane, the pituitary was divided into eight zones, in which the mean of area was 2.5-21.0%. The maximal cell density may reach 40-60%. The use of this map should help the pathologist to recognize if there is corticotropic hyperplasia in a small pituitary fragment surgically removed from a patient with Cushing's disease. On the basis of this study, we put forward some criteria for diagnosing corticotropic hyperplasia. PMID:8627004

  6. Prolactin-producing pituitary adenoma with atypical spindle cell morphology: a case report.

    PubMed

    Inoue, Ritsurou; Aoki, Mikiko; Matsumoto, Yoshihisa; Haraoka, Seiji; Kazekawa, Kiyoshi; Nabeshima, Kazuki

    2015-01-01

    Reported herein is a 25-year-old woman who was treated for a large and highly atypical prolactin-producing pituitary adenoma. On presentation, she exhibited right hemiparesis and left-sided visual loss, associated with amenorrhea. A massive (>5 cm) intra- and suprasellar lesion was seen on imaging, and her serum prolactin level was 4408 ng/ml. The patient received dopamine agonist treatment preoperatively for 4 weeks. To resect the tumor, a two-stage excision was required. Histologically, the specimen was composed of polygonal or spindle cells showing marked nuclear pleomorphism and/or multinucleation. Fibrosis was also focally conspicuous. Differential diagnoses included pituitary adenoma, pituitary carcinoma, pituicytoma, paraganglioma, spindle cell oncocytoma, and meningioma. Immunohistochemically, the tumor cells were positive for prolactin, chromogranin-A, and synaptophysin, but were negative for glial fibrillary acidic protein, S-100 protein, epithelial membrane antigen, and vimentin. No apparent cerebrospinal or systemic metastases are found. Ultimately, prolactin-producing pituitary adenoma was diagnosed. Our case highlights the difficulty in definitively diagnosing an unusual prolactin-producing adenoma based on histopathology alone and the importance of referring to clinical information and immunohistochemical findings when deriving the diagnosis. PMID:26228535

  7. Expression of Cold-Inducible RNA-Binding Protein (CIRP) in Pituitary Adenoma and its Relationships with Tumor Recurrence

    PubMed Central

    Wang, Mingguang; Zhang, Huan; Heng, Xueyuan; Pang, Qi; Sun, Aigang

    2015-01-01

    Background The aim of this study was to detect the expression of cold-inducible RNA-binding protein in pituitary adenoma and to determine its effects on tumor recurrence. Material/Methods We collected a total of 60 post-op samples collected from pituitary adenoma patients (including 20 cases of invasive pituitary adenoma, 20 cases of non-invasive adenoma, and 20 cases of non-invasive recurrent adenoma) admitted in our hospital. Both protein and mRNA levels of CIRP in 3 types of pituitary adenoma samples were quantified by Western blotting and real-time PCR, respectively. Results Western blotting revealed significantly elevated CIRP expression levels in invasive pituitary adenoma compared to non-invasive tumors, with statistical significance (p<0.05). Recurrent pituitary adenoma expressed significantly higher CIRP levels compared to non-recurrent tumors (p<0.05). Real-time PCR for CIRP mRNA obtained consistent results: transcript levels were significantly higher in invasive pituitary adenoma compared to non-invasive adenoma (p<0.05); recurrent adenoma also had significantly higher CIRP mRNA levels compared to non-recurrent tumors (p<0.05). Among all 3 types of pituitary adenoma, recurrent tumors had the highest levels of CIRP mRNA and protein. Conclusions The expression of CIRP in pituitary adenoma is closely related with tumor proliferation and invasion, and its significantly elevated expression level indicates post-op recurrence. PMID:25934796

  8. pNET co-secreting GHRH and calcitonin: ex vivo hormonal studies in human pituitary cells

    PubMed Central

    Rubinfeld, Hadara; Lysyy, Lyudmila; Schiller, Tal; Raverot, Véronique; Shimon, Ilan; Knobler, Hilla

    2016-01-01

    Summary Acromegaly due to ectopic GHRH secretion from a neuroendocrine tumor (NET) is rare and comprises <1% of all acromegaly cases. Herein we present a 57-year-old woman with clinical and biochemical features of acromegaly and a 6 cm pancreatic NET (pNET), secreting GHRH and calcitonin. Following surgical resection of the pancreatic tumor, IGF1, GH and calcitonin normalized, and the clinical features of acromegaly improved. In vitro studies confirmed that the tumor secreted large amounts of both GHRH and calcitonin, and incubation of pNET culture-derived conditioned media stimulated GH release from a cultured human pituitary adenoma. This is a unique case of pNET secreting both GHRH and calcitonin. The ability of the pNET-derived medium to stimulate in vitro GH release from a human pituitary-cell culture, combined with the clinical and hormonal remission following tumor resection, confirmed the ectopic source of acromegaly in this patient. Learning points Signs, symptoms and initial work-up of acromegaly due to ectopic GHRH secretion are similar to pituitary-dependent acromegaly. However, if no identifiable pituitary lesion is found, somatostatin receptor scan and further imaging (CT, MRI) should be performed.Detection of GHRH in the blood and in the tumor-derived medium supports the diagnosis of ectopic GHRH secretion.Functional bioactivity of pNET-secreted GHRH can be proved in vitro by releasing GH from human pituitary cells. PMID:26904199

  9. Purification and cultivation of human pituitary growth hormone secreting cells

    NASA Technical Reports Server (NTRS)

    Hymer, W. C.

    1979-01-01

    Efforts were directed towards maintenance of actively secreting human pituitary growth hormone cells (somatotrophs) in vitro. The production of human growth hormone (hGH) by this means would be of benefit for the treatment of certain human hypopituitary diseases such as dwarfism. One of the primary approaches was the testing of agents which may logically be expected to increase hGH release. The progress towards this goal is summarized. Results from preliminary experiments dealing with electrophoresis of pituitary cell for the purpose of somatotroph separation are described.

  10. Pancreatic islet cell tumor

    MedlinePlus

    Islet cell tumors; Islet of Langerhans tumor; Neuroendocrine tumors ... In the healthy pancreas, cells called islet cells produce hormones that regulate a several bodily functions. These include blood sugar level and the production of ...

  11. Adenoid Cystic Carcinoma Metastatic to the Pituitary: A Case Report and Discussion of Potential Diagnostic Value of Magnetic Resonance Elastography in Pituitary Tumors.

    PubMed

    D Hughes, Joshua; Retzlaff, Amber; Sims, John; O'Brien, Erin; Giannini, Caterina; Huston, John; Van Gompel, Jamie J

    2016-07-01

    Adenoid cystic carcinoma (ACC) is an exocrine gland tumor accounting for approximately 10%-15% of all epithelial salivary neoplasms and occurs most often in the parotid and submandibular glands. Metastatic pituitary tumors are rare, and there is only 1 previously reported case of parotid ACC metastatic to the pituitary. Magnetic resonance elastography (MRE) is a dynamic magnetic resonance imaging (MRI)-based technique that measures the propagation of mechanically induced shear waves through a particular tissue to determine stiffness and offers a method to evaluate tissue consistency. We present the case of a 72-year-old woman with a remote history of parotid gland ACC and subsequent lung metastases presented after a fall that resulted in facial trauma. A non-contrast head computed tomography scan revealed a sellar/suprasellar mass, and follow-up MRI revealed a well-defined, enhancing 3.8-cm lesion. MRE showed the tumor to be firm. The tumor was resected through a transsphenoidal approach and was consistent with the MRE findings. Pathology returned as metastatic ACC. We report the second case of ACC metastatic to pituitary and the first firm pituitary tumor found by MRE and discuss the potential diagnostic value of MRE in pituitary lesions. PMID:27018011

  12. Expression Analysis of the Hippo Cascade Indicates a Role in Pituitary Stem Cell Development

    PubMed Central

    Lodge, Emily J.; Russell, John P.; Patist, Amanda L.; Francis-West, Philippa; Andoniadou, Cynthia L.

    2016-01-01

    The pituitary gland is a primary endocrine organ that controls major physiological processes. Abnormal development or homeostatic disruptions can lead to human disorders such as hypopituitarism or tumors. Multiple signaling pathways, including WNT, BMP, FGF, and SHH regulate pituitary development but the role of the Hippo-YAP1/TAZ cascade is currently unknown. In multiple tissues, the Hippo kinase cascade underlies neoplasias; it influences organ size through the regulation of proliferation and apoptosis, and has roles in determining stem cell potential. We have used a sensitive mRNA in situ hybridization method (RNAscope) to determine the expression patterns of the Hippo pathway components during mouse pituitary development. We have also carried out immunolocalisation studies to determine when YAP1 and TAZ, the transcriptional effectors of the Hippo pathway, are active. We find that YAP1/TAZ are active in the stem/progenitor cell population throughout development and at postnatal stages, consistent with their role in promoting the stem cell state. Our results demonstrate for the first time the collective expression of major components of the Hippo pathway during normal embryonic and postnatal development of the pituitary gland. PMID:27065882

  13. Flow cytometric immunofluorescence of rat anterior pituitary cells

    NASA Technical Reports Server (NTRS)

    Hatfield, J. Michael; Hymer, W. C.

    1985-01-01

    A flow cytometric immunofluorescence technique was developed for the quantification of growth hormone, prolactin, and luteinizing hormone producing cells. The procedure is based on indirect-immunofluorescence of intracellular hormone using an EPICS V cell sorter and can objectively count 50,000 cells in about 3 minutes. It can be used to study the dynamics of pituitary cell populations under various physiological and pharmacological conditions.

  14. Electrophoretic separation of kidney and pituitary cells on STS-8

    NASA Astrophysics Data System (ADS)

    Morrison, D. R.; Nachtwey, D. S.; Barlow, G. H.; Cleveland, C.; Lanham, J. W.; Farrington, M. A.; Hatfield, J. M.; Hymer, W. C.; Todd, P.; Wilfinger, W.; Grindeland, R.; Lewis, M. L.

    A Continuous Flow Electrophoresis System (CFES) was used on Space Shuttle flight STS-8 to separate specific secretory cells from suspensions of cultured primary human embryonic kidney cells and rat pituitary cells. The objectives were to isolate the subfractions of kidney cells that produce the largest amounts of urokinase (plasminogen activator), and to isolate the subfractions of rat pituitary cells that secrete growth hormone, prolactin, and other hormones. Kidney cells were separated into more than 32 fractions in each of two electrophoretic runs. Electrophoretic mobility distributions in flight experiments were spread more than the ground controls. Multiple assay methods confirmed that all cultured kidney cell fractions produced some urokinase, and five to six fractions produced significantly more urokinase than the other fractions. Several fractions also produced tissue plasminogen activator. The pituitary cells were separated into 48 fractions in each of the two electrophoretic runs, and the amounts of growth hormone (GH) and prolactin (PRL) released into the medium for each cell fraction were determined. Cell fractions were grouped into eight mobility classes and immunocytochemically assayed for the presence of GH, PRL, ACTH, LH, TSH, and FSH. The patterns of hormone distribution indicate that the specialized cells producing GH and PRL are isolatable due to the differences in electrophoretic mobilities.

  15. Separation of cells from the rat anterior pituitary gland

    NASA Technical Reports Server (NTRS)

    Hymer, Wesley C.; Hatfield, J. Michael

    1983-01-01

    Various techniques for separating the hormone-producing cell types from the rat anterior pituitary gland are examined. The purity, viability, and responsiveness of the separated cells depend on the physiological state of the donor, the tissue dissociation procedures, the staining technique used for identification of cell type, and the cell separation technique. The chamber-gradient setup and operation, the characteristics of the gradient materials, and the separated cell analysis of velocity sedimentation techniques (in particular Staput and Celsep) are described. Consideration is given to the various types of materials used in density gradient centrifugation and the operation of a gradient generating device. The use of electrophoresis to separate rat pituitary cells is discussed.

  16. Feeding Frequency Affects Cultured Rat Pituitary Cells in Low Gravity

    NASA Technical Reports Server (NTRS)

    Hymer, W. C.; Grindeland, R. E.; Salada, T.; Cenci, R.; Krishnan, K.; Mukai, C.; Nagaoka, S.

    1996-01-01

    In this report, we describe the results of a rat pituitary cell culture experiment done on STS-65 in which the effect of cell feeding on the release of the six anterior pituitary hormones was studied. We found complex microgravity related interactions between the frequency of cell feeding and the quantity and quality (i.e. biological activity) of some of the six hormones released in flight. Analyses of growth hormone (GH) released from cells into culture media on different mission days using gel filtration and ion exchange chromatography yielded qualitatively similar results between ground and flight samples. Lack of cell feeding resulted in extensive cell clumping in flight (but not ground) cultures. Vigorous fibroblast growth occurred in both ground and flight cultures fed 4 times. These results are interpreted within the context of autocrine and or paracrine feedback interactions. Finally the payload specialist successfully prepared a fresh trypsin solution in microgravity, detached the cells from their surface and reinserted them back into the culture chamber. These cells reattached and continued to release hormone in microgravity. In summary, this experiment shows that pituitary cells are microgravity sensitive and that coupled operations routinely associated with laboratory cel1 culture can also be accomplished in low gravity.

  17. Quantitative trait loci for estrogen-dependent pituitary tumor growth in the rat.

    PubMed

    Wendell, D L; Gorski, J

    1997-01-01

    Growth control is of fundamental importance to biology in general and of critical importance to cancer research in particular. Tumors develop when control of the normal growth process is lost. The rat pituitary is a model system for control of estrogen-dependent growth. Chronic estrogen treatment induces uncontrolled growth in the pituitaries of Fischer 344 (F344) rats, but not of Brown Norway (BN) rats. We have identified five quantitative trait loci (QTL) for estrogen-dependent pituitary mass (Edpm) in an F2 intercross of F344 and BN. These QTL reside on rat Chromosomes (Chrs) 2, 3, 5, and 9 and explain a total of 55% of the genetic variance in the F2. We have also detected suggestive evidence for a QTL on rat Chr 14. For Edpm2-1, Edpm2-2, Edpm3, and Edpm5, the F344 allele corresponds with increased pituitary mass, as expected. Surprisingly, for Edpm9 and the suggested QTL on Chr 14, the BN allele corresponds with increased pituitary mass. We also find evidence for interaction (epistasis) between Edpm3 and Edpm9 and between Edpm5 and the suggested QTL on Chr 14. PMID:9337394

  18. Clinical significance of screening for subclinical Cushing's disease in patients with pituitary tumors.

    PubMed

    Tamada, Daisuke; Kitamura, Tetsuhiro; Otsuki, Michio; Oshino, Satoru; Saitoh, Youichi; Shimomura, Iichiro

    2016-01-01

    Cushing's syndrome (CS) is a clinical state caused by chronic excess of glucocorticoid, and results in hypertension, impaired glucose tolerance, and dyslipidemia. Recently, a mild state of pituitary CS without typical Cushingoid appearance (subclinical Cushing's disease; SCD) has been identified. However, the true prevalence of SCD and its effect on metabolic disorders remain obscure. The aim of this prospective study was to determine the prevalence of SCD according to the guideline proposed by the working group of the Japanese Ministry of Health, Welfare and Labor, and to assess the outcome of surgery on metabolic disorders. The prevalence of SCD was investigated in 105 consecutive patients diagnosed with pituitary adenomas by MRI. ACTH-dependent hypercortisolism was diagnosed based on the results of the 0.5 mg dexamethasone suppression test (serum cortisol >3.0 μg/dL) plus one positive finding of the following two tests: midnight serum cortisol level >5.0 μg/dL or ACTH increase >50% after 1-deamino-5-D-arginine vasopressin (DDAVP) challenge. The final diagnosis of SCD was established by positive staining for ACTH in surgically-excised pituitary adenoma. Three patients (4.8%) were diagnosed with SCD among 62 patients with pituitary adenoma. Transsphenoidal adenomectomy partially resulted in improvement of blood pressure and glucose metabolism in SCD patients. Our results emphasize the importance of SCD screening in patients with pituitary tumors, especially in those patients with metabolic disorders. PMID:26536898

  19. Functional anterior pituitary generated in self-organizing culture of human embryonic stem cells

    PubMed Central

    Ozone, Chikafumi; Suga, Hidetaka; Eiraku, Mototsugu; Kadoshima, Taisuke; Yonemura, Shigenobu; Takata, Nozomu; Oiso, Yutaka; Tsuji, Takashi; Sasai, Yoshiki

    2016-01-01

    Anterior pituitary is critical for endocrine systems. Its hormonal responses to positive and negative regulators are indispensable for homeostasis. For this reason, generating human anterior pituitary tissue that retains regulatory hormonal control in vitro is an important step for the development of cell transplantation therapy for pituitary diseases. Here we achieve this by recapitulating mouse pituitary development using human embryonic stem cells. We find that anterior pituitary self-forms in vitro following the co-induction of hypothalamic and oral ectoderm. The juxtaposition of these tissues facilitated the formation of pituitary placode, which subsequently differentiated into pituitary hormone-producing cells. They responded normally to both releasing and feedback signals. In addition, after transplantation into hypopituitary mice, the in vitro-generated corticotrophs rescued physical activity levels and survival of the hosts. Thus, we report a useful methodology for the production of regulator-responsive human pituitary tissue that may benefit future studies in regenerative medicine. PMID:26762480

  20. Functional anterior pituitary generated in self-organizing culture of human embryonic stem cells.

    PubMed

    Ozone, Chikafumi; Suga, Hidetaka; Eiraku, Mototsugu; Kadoshima, Taisuke; Yonemura, Shigenobu; Takata, Nozomu; Oiso, Yutaka; Tsuji, Takashi; Sasai, Yoshiki

    2016-01-01

    Anterior pituitary is critical for endocrine systems. Its hormonal responses to positive and negative regulators are indispensable for homeostasis. For this reason, generating human anterior pituitary tissue that retains regulatory hormonal control in vitro is an important step for the development of cell transplantation therapy for pituitary diseases. Here we achieve this by recapitulating mouse pituitary development using human embryonic stem cells. We find that anterior pituitary self-forms in vitro following the co-induction of hypothalamic and oral ectoderm. The juxtaposition of these tissues facilitated the formation of pituitary placode, which subsequently differentiated into pituitary hormone-producing cells. They responded normally to both releasing and feedback signals. In addition, after transplantation into hypopituitary mice, the in vitro-generated corticotrophs rescued physical activity levels and survival of the hosts. Thus, we report a useful methodology for the production of regulator-responsive human pituitary tissue that may benefit future studies in regenerative medicine. PMID:26762480

  1. Functional screen analysis reveals miR-26b and miR-128 as central regulators of pituitary somatomammotrophic tumor growth through activation of the PTEN-AKT pathway.

    PubMed

    Palumbo, T; Faucz, F R; Azevedo, M; Xekouki, P; Iliopoulos, D; Stratakis, C A

    2013-03-28

    MicroRNAs (miRNAs) have been involved in the pathogenesis of different types of cancer; however, their function in pituitary tumorigenesis remains poorly understood. Cyclic-AMP-dependent protein kinase-defective pituitaries occasionally form aggressive growth-hormone (GH)-producing pituitary tumors in the background of hyperplasia caused by haploinsufficiency of the protein kinase's main regulatory subunit, PRKAR1A. The molecular basis for this development remains unknown. We have identified a 17-miRNA signature of pituitary tumors formed in the background of hyperplasia (caused in half of the cases by PRKAR1A-mutations). We selected two miRNAs on the basis of their functional screen analysis: inhibition of miR-26b expression and upregulation of miR-128 suppressed the colony formation ability and invasiveness of pituitary tumor cells. Furthermore, we identified that miR-26b and miR-128 affected pituitary tumor cell behavior through regulation of their direct targets, PTEN and BMI1, respectively. In addition, we found that miR-128 through BMI1 direct binding on the PTEN promoter affected PTEN expression levels and AKT activity in the pituitary tumor cells. Our in vivo data revealed that inhibition of miR-26b and overexpression of miR-128 could suppress pituitary GH3 tumor growth in xenografts. Taken together, we have identified a miRNA signature for GH-producing pituitary tumors and found that miR-26b and miR-128 regulate the activity of the PTEN-AKT pathway in these tumors. This is the first suggestion of the possible involvement of miRNAs regulating the PTEN-AKT pathway in GH-producing pituitary tumor formation in the context of hyperplasia or due to germline PRKAR1A defects. MiR-26b suppression and miR-128 upregulation could have therapeutic potential in GH-producing pituitary tumor patients. PMID:22614013

  2. Reversal of endogenous dopamine receptor silencing in pituitary cells augments receptor-mediated apoptosis.

    PubMed

    Al-Azzawi, Haneen; Yacqub-Usman, Kiren; Richardson, Alan; Hofland, Leo J; Clayton, Richard N; Farrell, William E

    2011-02-01

    Dopamine (DA)-agonist targeting of the DA D(2) receptor (D2R) in prolactinomas is the first-line treatment choice for suppression of prolactin and induction of tumor shrinkage. Resistance to DA agonists seems to be related to receptor number. Using the MMQ and GH3 pituitary cell lines, that either do or do not express D2R, respectively, we explored the epigenetic profile associated with the presence or absence of D2R in these cells lines. These studies led us to explore pharmacological strategies designed to restore receptor expression and thereby potentially augment DA agonist-mediated apoptosis. We show in GH3 cells that the D2R harbors increased CpG island-associated methylation and enrichment for histone H3K27me3. Conversely, MMQ cells and normal pituitaries show enrichment for H3K9Ac and barely detectable H3K27me3. Coculture of GH3 cells with the demethylating agent zebularine and the histone deacetylase inhibitor trichostatin A was responsible for a decrease in CpG island methylation and enrichment for the histone H3K9Ac mark. In addition, challenge of GH3 cells with zebularine alone or coculture with both agents led to expression of endogenous D2R in these cells. Induced expression D2R in GH3 cells was associated with a significant increase in apoptosis indices to challenge with either DA or bromocriptine. Specificity of a receptor-mediated response was established in coincubations with specific D2R antagonist and siRNA approaches in GH3 cell and D2R expressing MMQ cell lines. These studies point to the potential efficacy of combined treatment with epigenetic drugs and DA agonists for the medical management of different pituitary tumor subtypes, resistant to conventional therapies. PMID:21177832

  3. Prokaryotic adenylate cyclase toxin stimulates anterior pituitary cells in culture

    SciTech Connect

    Cronin, M.J.; Evans, W.S.; Rogol, A.D.; Weiss, A.A.; Thorner, M.O.; Orth, D.N.; Nicholson, W.E.; Yasumoto, T.; Hewlett, E.L.

    1986-08-01

    Bordetella pertussis synthesis a variety of virulence factors including a calmodulin-dependent adenylate cyclase (AC) toxin. Treatment of anterior pituitary cells with this AC toxin resulted in an increase in cellular cAMP levels that was associated with accelerated exocytosis of growth hormone (GH), prolactin, adrenocorticotropic hormone (ACTH), and luteinizing hormone (LH). The kinetics of release of these hormones, however, were markedly different; GH and prolactin were rapidly released, while LH and ACTH secretion was more gradually elevated. Neither dopamine agonists nor somatostatin changes the ability of AC toxin to generate cAMP (up to 2 h). Low concentrations of AC toxin amplified the secretory response to hypophysiotrophic hormones. The authors conclude that bacterial AC toxin can rapidly elevate cAMP levels in anterior pituitary cells and that it is the response that explains the subsequent acceleration of hormone release.

  4. Genetic and epigenetic mutations of tumor suppressive genes in sporadic pituitary adenoma.

    PubMed

    Zhou, Yunli; Zhang, Xun; Klibanski, Anne

    2014-04-01

    Human pituitary adenomas are the most common intracranial neoplasms. Approximately 5% of them are familial adenomas. Patients with familial tumors carry germline mutations in predisposition genes, including AIP, MEN1 and PRKAR1A. These mutations are extremely rare in sporadic pituitary adenomas, which therefore are caused by different mechanisms. Multiple tumor suppressive genes linked to sporadic tumors have been identified. Their inactivation is caused by epigenetic mechanisms, mainly promoter hypermethylation, and can be placed into two groups based on their functional interaction with tumor suppressors RB or p53. The RB group includes CDKN2A, CDKN2B, CDKN2C, RB1, BMP4, CDH1, CDH13, GADD45B and GADD45G; AIP and MEN1 genes also belong to this group. The p53 group includes MEG3, MGMT, PLAGL1, RASSF1, RASSF3 and SOCS1. We propose that the tumor suppression function of these genes is mainly mediated by the RB and p53 pathways. We also discuss possible tumor suppression mechanisms for individual genes. PMID:24035864

  5. Purification and Cultivation of Human Pituitary Growth Hormones Secreting Cells

    NASA Technical Reports Server (NTRS)

    Hymer, W. C.; Todd, P.; Grindeland, R.; Lanham, W.; Morrison, D.

    1985-01-01

    The rat and human pituitary gland contains a mixture of hormone producing cell types. The separation of cells which make growth hormone (GH) is attempted for the purpose of understanding how the hormone molecule is made within the pituitary cell; what form(s) it takes within the cell; and what form(s) GH assumes as it leaves the cell. Since GH has a number of biological targets (e.g., muscle, liver, bone), the assessment of the activities of the intracellular/extracellular GH by new and sensitive bioassays. GH cells contained in the mixture was separated by free flow electrophoresis. These experiments show that GH cells have different electrophoretic mobilities. This is relevant to NASA since a lack of GH could be a prime causative factor in muscle atrophy. Further, GH has recently been implicated in the etiology of motion sickness in space. Continous flow electrophoresis experiment on STS-8 showed that GH cells could be partially separated in microgravity. However, definitive cell culture studies could not be done due to insufficient cell recoveries.

  6. Lower prolactin levels during cabergoline treatment are associated to tumor shrinkage in prolactin secreting pituitary adenoma.

    PubMed

    Lombardi, M; Lupi, I; Cosottini, M; Rossi, G; Manetti, L; Raffaelli, V; Sardella, C; Martino, E; Bogazzi, F

    2014-12-01

    Dopamine agonists are considered as the first line therapy in prolactin (PRL) secreting pituitary adenomas inducing a normalization of serum PRL and reduction of tumor size. It is known that serum PRL levels, obtained during treatment, are a predictor of tumor shrinkage. Whether PRL suppression below the lower limit of the normal range is related to a greater chance of tumor shrinkage than just its normalization has not been established. This retrospective cohort study was carried out in a tertiary center. Clinical records of 151 patients with PRL-secreting pituitary adenomas (73 micro-, 78 macroadenomas) treated with cabergoline for at least 24 months were analyzed. The adenoma size was analyzed by MRI before and after 24 months of treatment. PRL levels were evaluated every 6 months, assigning a score at each time point (PRL 0 = suppressed; 1 = normal; 2 = above normal). The total score, after 24 months of treatment, was expressed as the sum of the score at each time point and ranged between 0 and 8. A tumor shrinkage was observed in 102/151 patients (67.5%) and it was significantly associated to a lower PRL total score (p = 0.021, OR = 0.85, CI = 0.73-0.97), being significantly more frequent in patients with suppressed PRL than in those with normal PRL (p = 0.045, OR = 0.42, CI = 0.18-0.98) at 24 months. Cabergoline therapy with the goal of achieving PRL levels below the lower limit of normal range can increase the chance to obtain tumor shrinkage of PRL-secreting pituitary adenomas. PMID:25230324

  7. Cold inducible RNA binding protein upregulation in pituitary corticotroph adenoma induces corticotroph cell proliferation via Erk signaling pathway

    PubMed Central

    Fu, Wei; Tang, Hao; Chen, Xiao; Zhao, Yao; Zheng, Lili; Pan, Sijian; Wang, Weiqing; Bian, Liuguan; Sun, Qingfang

    2016-01-01

    Cushing's disease is caused by pituitary corticotroph adenoma, and the pathogenesis of it has remained obscure. Here, we showed that cold inducible RNA binding protein (CIRP) was markedly elevated in corticotroph tumors. Forced overexpression of CIRP in murine AtT20 pituitary corticotroph cell line increased corticotroph precursor hormone proopiomelanocortin (POMC) transcription, ACTH secretion and cellular proliferation. In vivo, CIRP overexpression promotes murine corticotroph tumor growth and enhances ACTH production. Mechanistically, we show that CIRP could promote AtT20 cells proliferation by inducing cyclinD1 and decreasing p27 expression via Erk1/2 signaling pathway. Clinically, CIRP overexpression is significantly correlated with Cushing's disease recurrence. CIRP appears to play a critical tumorigenesis function in Cushing's disease and its expression might be a useful biomarker for tumor recurrence. PMID:26824322

  8. Structure-Based Screen Identification of a Mammalian Ste20-like Kinase 4 (MST4) Inhibitor with Therapeutic Potential for Pituitary Tumors.

    PubMed

    Xiong, Weipeng; Matheson, Christopher J; Xu, Mei; Backos, Donald S; Mills, Taylor S; Salian-Mehta, Smita; Kiseljak-Vassiliades, Katja; Reigan, Philip; Wierman, Margaret E

    2016-03-01

    Pituitary tumors of the gonadotrope lineage are often large and invasive, resulting in hypopituitarism. No medical treatments are currently available. Using a combined genetic and genomic screen of individual human gonadotrope pituitary tumor samples, we recently identified the mammalian sterile-20 like kinase 4 (MST4) as a protumorigenic effector, driving increased pituitary cell proliferation and survival in response to a hypoxic microenvironment. To identify novel inhibitors of the MST4 kinase for potential future clinical use, computational-based virtual library screening was used to dock the SelleckChem kinase inhibitor library into the ATP-binding site of the MST4 crystal structure. Several inhibitor candidates were identified with the potential to bind with high affinity. Using a TR-FRET in vitro recombinant kinase assay, hesperadin, initially described as an Aurora kinase inhibitor, exhibited potent inhibition of the MST4 kinase at nanomolar concentrations. The LβT2 gonadotrope pituitary cell hypoxic model was used to test the ability of this inhibitor to antagonize MST4 actions. Under short-term severe hypoxia (1% O2), MST4 protection from hypoxia-induced apoptosis was abrogated in the presence of hesperadin. Similarly, under chronic hypoxia (5%), hesperadin blocked the proliferative and colony-forming actions of MST4 as well as the ability to activate specific downstream signaling and hypoxia-inducible factor-1 effectors. Together, these data identify hesperadin as the first potent, selective inhibitor of the MST4 kinase with the capacity to block pituitary tumor cell growth in a hypoxic microenvironment. PMID:26721946

  9. Co-expression network analysis of differentially expressed genes associated with metastasis in prolactin pituitary tumors.

    PubMed

    Zhang, Wei; Zang, Zhenle; Song, Yechun; Yang, Hui; Yin, Qing

    2014-07-01

    The aim of the present study was to construct a co‑expression network of differently expressed genes (DEGs) in prolactin pituitary (PRL) tumor metastasis. The gene expression profile, GSE22812 was downloaded from the Gene Expression Omnibus database, and including five non‑invasive, two invasive and six aggressive‑invasive PRL tumor samples. Compared with non‑invasive samples, DEGs were identified in invasive and aggressive‑invasive samples using a limma package in R language. The expression values of DEGs were hierarchically clustered. Next, Gene Ontology (GO) function enrichment and Kyoto Encyclopedia of Genes and Genomes pathway analysis of DEGs were performed via The Database for Annotation, Visualization and Integrated Discovery. Finally, gene pairs of DEGs between non‑invasive and aggressive‑invasive samples were identified using the Spearman cor( ) function in R language. Compared with the non‑invasive samples, 61 and 89 DEGs were obtained from invasive and aggressive‑invasive samples, respectively. Cluster analysis showed that four genes were shared by the two samples, including upregulated solute carrier family 2, facilitated glucose transporter member 11 (SLC2A11) and teneurin transmembrane protein 1 (TENM1) and downregulated importin 7 (IPO7) and chromogranin B (CHGB). In the invasive samples, the most significant GO terms responded to cyclic adenosine monophosphate and a glucocorticoid stimulus. However, this occurred in the cell cycle, and was in response to hormone stimulation in aggressive‑invasive samples. The co‑expression network of DEGs showed different gene pairs and modules, and SLC2A11 and CHGB occurred in two co‑expression networks within different co‑expressed pairs. In the present study, the co‑expression network was constructed using bioinformatics methods. SLC2A11, TENM1, IPO7 and CHGB are hypothesized to be closely associated with metastasis of PRL. Furthermore, CHGB and SLC2A11 may be significant in PRL

  10. Utility of Early Post-operative High Resolution Volumetric MR Imaging after Transsphenoidal Pituitary Tumor Surgery

    PubMed Central

    Patel, Kunal S.; Kazam, Jacob; Tsiouris, Apostolos J.; Anand, Vijay K.; Schwartz, Theodore H.

    2014-01-01

    Objective Controversy exists over the utility of early post-operative magnetic resonance imaging (MRI) after transsphenoidal pituitary surgery for macroadenomas. We investigate whether valuable information can be derived from current higher resolution scans. Methods Volumetric MRI scans were obtained in the early (<10 days) and late (>30 days) post-operative periods in a series of patients undergoing transsphenoidal pituitary surgery. The volume of the residual tumor, resection cavity, and corresponding visual field tests were recorded at each time point. Statistical analyses of changes in tumor volume and cavity size were calculated using the late MRI as the gold standard. Results 40 patients met the inclusion criteria. Pre-operative tumor volume averaged 8.8 cm3. Early postoperative assessment of average residual tumor volume (1.18 cm3) was quite accurate and did not differ statistically from late post-operative volume (1.23 cm3, p=.64), indicating the utility of early scans to measure residual tumor. Early scans were 100% sensitive and 91% specific for predicting ≥ 98% resection (p<.001, Fisher’s exact test). The average percent decrease in cavity volume from pre-operative MRI (tumor volume) to early post-operative imaging was 45% with decreases in all but 3 patients. There was no correlation between the size of the early cavity and the visual outcome. Conclusions Early high resolution volumetric MRI is valuable in determining the presence or absence of residual tumor. Cavity volume almost always decreases after surgery and a lack of decrease should alert the surgeon to possible persistent compression of the optic apparatus that may warrant re-operation. PMID:25045791

  11. Assessment of Environmental and Hereditary Influence on Development of Pituitary Tumors Using Dermatoglyphic Traits and Their Potential as Screening Markers.

    PubMed

    Gradiser, Marina; Matovinovic Osvatic, Martina; Dilber, Dario; Bilic-Curcic, Ines

    2016-01-01

    The aim of this study was to assess environmental and hereditary influence on development of pituitary tumors using dermatoglyphic traits. The study was performed on 126 patients of both genders with pituitary tumors (60 non-functional and 66 functional pituitary tumor patients) in comparison to the control group of 400 phenotypically healthy individuals. Statistical analysis of quantitative and qualitative traits of digito-palmar dermatoglyphics was performed, and hormonal status was determined according to the standard protocols. Although we did not find markers that could specifically distinguish functional from non-functional tumors, we have found markers predisposing to the development of tumors in general (a small number of ridges between triradius of both hands, a smaller number of ridges between the triradius of c-d rc R), those for endocrine dysfunction (increased number of arches and reduced number of whorls, difference of pattern distribution in the I3 and I4 interdigital space), and some that could potentially be attributed to patients suffering from pituitary tumors (small number of ridges for variables FRR 5, smaller number of ridges in the FRL 4 of both hands and difference of pattern distribution at thenar of I1 and I2 interdigital space). The usage of dermatoglyphic traits as markers of predisposition of pituitary tumor development could facilitate the earlier detection of patients in addition to standard methods, and possibly earlier treatment and higher survival rate. Finally, our results are consistent with the hypothesis about multifactorial nature of pituitary tumor etiology comprised of both gene instability and environmental factors. PMID:26999178

  12. Assessment of Environmental and Hereditary Influence on Development of Pituitary Tumors Using Dermatoglyphic Traits and Their Potential as Screening Markers

    PubMed Central

    Gradiser, Marina; Matovinovic Osvatic, Martina; Dilber, Dario; Bilic-Curcic, Ines

    2016-01-01

    The aim of this study was to assess environmental and hereditary influence on development of pituitary tumors using dermatoglyphic traits. The study was performed on 126 patients of both genders with pituitary tumors (60 non-functional and 66 functional pituitary tumor patients) in comparison to the control group of 400 phenotypically healthy individuals. Statistical analysis of quantitative and qualitative traits of digito-palmar dermatoglyphics was performed, and hormonal status was determined according to the standard protocols. Although we did not find markers that could specifically distinguish functional from non-functional tumors, we have found markers predisposing to the development of tumors in general (a small number of ridges between triradius of both hands, a smaller number of ridges between the triradius of c–d rc R), those for endocrine dysfunction (increased number of arches and reduced number of whorls, difference of pattern distribution in the I3 and I4 interdigital space), and some that could potentially be attributed to patients suffering from pituitary tumors (small number of ridges for variables FRR 5, smaller number of ridges in the FRL 4 of both hands and difference of pattern distribution at thenar of I1 and I2 interdigital space). The usage of dermatoglyphic traits as markers of predisposition of pituitary tumor development could facilitate the earlier detection of patients in addition to standard methods, and possibly earlier treatment and higher survival rate. Finally, our results are consistent with the hypothesis about multifactorial nature of pituitary tumor etiology comprised of both gene instability and environmental factors. PMID:26999178

  13. Birthdating studies reshape models for pituitary gland cell specification.

    PubMed

    Davis, Shannon W; Mortensen, Amanda H; Camper, Sally A

    2011-04-15

    The intermediate and anterior lobes of the pituitary gland are derived from an invagination of oral ectoderm that forms Rathke's pouch. During gestation proliferating cells are enriched around the pouch lumen, and they appear to delaminate as they exit the cell cycle and differentiate. During late mouse gestation and the postnatal period, anterior lobe progenitors re-enter the cell cycle and expand the populations of specialized, hormone-producing cells. At birth, all cell types are present, and their localization appears stratified based on cell type. We conducted a birth dating study of Rathke's pouch derivatives to determine whether the location of specialized cells at birth is correlated with the timing of cell cycle exit. We find that all of the anterior lobe cell types initiate differentiation concurrently with a peak between e11.5 and e13.5. Differentiation of intermediate lobe melanotropes is delayed relative to anterior lobe cell types. We discovered that specialized cell types are not grouped together based on birth date and are dispersed throughout the anterior lobe. Thus, the apparent stratification of specialized cells at birth is not correlated with cell cycle exit. Thus, the currently popular model of cell specification, dependent upon timing of extrinsic, directional gradients of signaling molecules, needs revision. We propose that signals intrinsic to Rathke's pouch are necessary for cell specification between e11.5 and e13.5 and that cell-cell communication likely plays an important role in regulating this process. PMID:21262217

  14. Risk assessment of thyroid follicular cell tumors.

    PubMed Central

    Hill, R N; Crisp, T M; Hurley, P M; Rosenthal, S L; Singh, D V

    1998-01-01

    Thyroid follicular cell tumors arise in rodents from mutations, perturbations of thyroid and pituitary hormone status with increased stimulation of thyroid cell growth by thyroid-stimulating hormone (TSH), or a combination of the two. The only known human thyroid carcinogen is ionizing radiation. It is not known for certain whether chemicals that affect thyroid cell growth lead to human thyroid cancer. The U.S. Environmental Protection Agency applies the following science policy positions: 1) chemically induced rodent thyroid tumors are presumed to be relevant to humans; 2) when interspecies information is lacking, the default is to assume comparable carcinogenic sensitivity in rodents and humans; 3) adverse rodent noncancer thyroid effects due to chemically induced thyroid-pituitary disruption are presumed to be relevant to humans; 4) linear dose-response considerations are applied to thyroid cancer induced by chemical substances that either do not disrupt thyroid functioning or lack mode of action information; 5) nonlinear thyroid cancer dose-response considerations are applied to chemicals that reduce thyroid hormone levels, increase TSH and thyroid cell division, and are judged to lack mutagenic activity; and 6) nonlinear considerations may be applied in thyroid cancer dose-response assessments on a case-by-case basis for chemicals that disrupt thyroid-pituitary functioning and demonstrate some mutagenic activity. Required data for risk assessment purposes is mode of action information on mutagenicity, increases in follicular cell growth (cell size and number) and thyroid gland weight, thyroid-pituitary hormones, site of action, correlations between doses producing thyroid effects and cancer, and reversibility of effects when dosing ceases. Images Figure 1 Figure 2 Figure 3 PMID:9681971

  15. Pituitary tumor

    MedlinePlus

    ... or more of the following conditions can occur: Hyperthyroidism (thyroid gland makes too much of its hormones; ... syndrome Cyst Endocrine glands Gigantism Growth hormone test Hyperthyroidism Hypopituitarism Multiple endocrine neoplasia (MEN) I Prolactin blood ...

  16. Ethanol Alters Production and Secretion of Estrogen-Regulated Growth Factors That Control Prolactin-Secreting Tumors in the Pituitary

    PubMed Central

    Sarkar, Dipak K.; Boyadjieva, Nadka I.

    2010-01-01

    Background Chronic administration of ethanol increases plasma prolactin levels and enhances estradiol’s mitogenic action on the lactotropes of the pituitary gland. The present study was conducted to determine whether ethanol’s lactotropic cell-proliferating action, like estradiol’s, is associated with alteration in the production of 3 peptides that regulate cell growth: transforming growth factor beta 1 (TGF-β1), TGF-β3 and basic fibroblast growth factor (bFGF). Methods Using ovariectomized Fischer-344 female rats, we determined ethanol’s and estradiol’s actions on lactotropic cell proliferation and growth-regulatory peptide production and release in the pituitary gland during tumorigenesis. Results Ethanol increased basal and estradiol-enhanced mitosis of lactotropes in the pituitary glands of ovariectomized rats. The level of growth-inhibitory TGF-β1 was reduced in the pituitary following ethanol and/or estradiol treatment for 2 and 4 weeks. In contrast, ethanol and estradiol alone as well as together increased levels of growth-stimulatory TGF-β3 and bFGF in the pituitary at 2 and 4 weeks. In primary cultures of pituitary cells, both ethanol and estradiol reduced TGF-β1 release and increased TGF-β3 and bFGF release at 24 hours. Ethanol’s effect on growth factor levels in the pituitary or growth factor release from the pituitary cells was less than that of estradiol. When ethanol and estradiol were applied together, their individual effects on these growth factors were amplified. Conclusions These results confirm estradiol’s modulation of pituitary growth factor production and release, and provide evidence that ethanol, like estradiol, alters the production and secretion of growth-regulatory peptides controlling lactotropic cell proliferation. PMID:18034699

  17. Establishment and culture optimization of a new type of pituitary immortalized cell line

    SciTech Connect

    Kokubu, Yuko; Asashima, Makoto; Kurisaki, Akira

    2015-08-07

    The pituitary gland is a center of the endocrine system that controls homeostasis in an organism by secreting various hormones. The glandular anterior pituitary consists of five different cell types, each expressing specific hormones. However, their regulation and the appropriate conditions for their in vitro culture are not well defined. Here, we report the immortalization of mouse pituitary cells by introducing TERT, E6, and E7 transgenes. The immortalized cell lines mainly expressed a thyrotroph-specific thyroid stimulating hormone beta (Tshb). After optimization of the culture conditions, these immortalized cells proliferated and maintained morphological characteristics similar to those of primary pituitary cells under sphere culture conditions in DMEM/F12 medium supplemented with N2, B27, basic FGF, and EGF. These cell lines responded to PKA or PKC pathway activators and induced the expression of Tshb mRNA. Moreover, transplantation of the immortalized cell line into subcutaneous regions and kidney capsules of mice further increased Tshb expression. These results suggest that immortalization of pituitary cells with TERT, E6, and E7 transgenes is a useful method for generating proliferating cells for the in vitro analysis of pituitary regulatory mechanisms. - Highlights: • Mouse pituitary cell lines were immortalized by introducing TERT, E6, and E7. • The immortalized cell lines mainly expressed thyroid stimulating hormone beta. • The cell lines responded to PKA or PKC pathway activators, and induced Tshb.

  18. In vitro impact of pegvisomant on growth hormone-secreting pituitary adenoma cells.

    PubMed

    Cuny, Thomas; Zeiller, Caroline; Bidlingmaier, Martin; Défilles, Céline; Roche, Catherine; Blanchard, Marie-Pierre; Theodoropoulou, Marily; Graillon, Thomas; Pertuit, Morgane; Figarella-Branger, Dominique; Enjalbert, Alain; Brue, Thierry; Barlier, Anne

    2016-07-01

    Pegvisomant (PEG), an antagonist of growth hormone (GH)-receptor (GHR), normalizes insulin-like growth factor 1 (IGF1) oversecretion in most acromegalic patients unresponsive to somatostatin analogs (SSAs) and/or uncontrolled by transsphenoidal surgery. The residual GH-secreting tumor is therefore exposed to the action of circulating PEG. However, the biological effect of PEG at the pituitary level remains unknown. To assess the impact of PEG in vitro on the hormonal secretion (GH and prolactin (PRL)), proliferation and cellular viability of eight human GH-secreting tumors in primary cultures and of the rat somatolactotroph cell line GH4C1. We found that the mRNA expression levels of GHR were characterized in 31 human GH-secreting adenomas (0.086 copy/copy β-Gus) and the GHR was identified by immunocytochemistry staining. In 5/8 adenomas, a dose-dependent inhibition of GH secretion was observed under PEG with a maximum of 38.2±17% at 1μg/mL (P<0.0001 vs control). A dose-dependent inhibition of PRL secretion occurred in three mixed GH/PRL adenomas under PEG with a maximum of 52.8±11.5% at 10μg/mL (P<0.0001 vs control). No impact on proliferation of either human primary tumors or GH4C1 cell line was observed. We conclude that PEG inhibits the secretion of GH and PRL in primary cultures of human GH(/PRL)-secreting pituitary adenomas without effect on cell viability or cell proliferation. PMID:27267119

  19. EMT Involved in Migration of Stem/Progenitor Cells for Pituitary Development and Regeneration

    PubMed Central

    Yoshida, Saishu; Kato, Takako; Kato, Yukio

    2016-01-01

    Epithelial–mesenchymal transition (EMT) and cell migration are important processes in embryonic development of many tissues as well as oncogenesis. The pituitary gland is a master endocrine tissue and recent studies indicate that Sox2-expressing stem/progenitor cells actively migrate and develop this tissue during embryogenesis. Notably, although migration activity of stem/progenitor cells in the postnatal period seems to be reduced compared to that in the embryonic period, it is hypothesized that stem/progenitor cells in the adult pituitary re-migrate from their microenvironment niche to contribute to the regeneration system. Therefore, elucidation of EMT in the pituitary stem/progenitor cells will promote understanding of pituitary development and regeneration, as well as diseases such as pituitary adenoma. In this review, so as to gain more insights into the mechanisms of pituitary development and regeneration, we summarize the EMT in the pituitary by focusing on the migration of pituitary stem/progenitor cells during both embryonic and postnatal organogenesis. PMID:27058562

  20. EMT Involved in Migration of Stem/Progenitor Cells for Pituitary Development and Regeneration.

    PubMed

    Yoshida, Saishu; Kato, Takako; Kato, Yukio

    2016-01-01

    Epithelial-mesenchymal transition (EMT) and cell migration are important processes in embryonic development of many tissues as well as oncogenesis. The pituitary gland is a master endocrine tissue and recent studies indicate that Sox2-expressing stem/progenitor cells actively migrate and develop this tissue during embryogenesis. Notably, although migration activity of stem/progenitor cells in the postnatal period seems to be reduced compared to that in the embryonic period, it is hypothesized that stem/progenitor cells in the adult pituitary re-migrate from their microenvironment niche to contribute to the regeneration system. Therefore, elucidation of EMT in the pituitary stem/progenitor cells will promote understanding of pituitary development and regeneration, as well as diseases such as pituitary adenoma. In this review, so as to gain more insights into the mechanisms of pituitary development and regeneration, we summarize the EMT in the pituitary by focusing on the migration of pituitary stem/progenitor cells during both embryonic and postnatal organogenesis. PMID:27058562

  1. Regulatory System for Stem/Progenitor Cell Niches in the Adult Rodent Pituitary

    PubMed Central

    Yoshida, Saishu; Kato, Takako; Kato, Yukio

    2016-01-01

    The anterior lobe of the pituitary gland is a master endocrine tissue composed of five types of endocrine cells. Although the turnover rate of pituitary endocrine cells is as low as about 1.6% per day, recent studies have demonstrated that Sex-determining region Y-box 2 (SOX2)+-cells exist as pituitary stem/progenitor cells in the adult anterior lobe and contribute to cell regeneration. Notably, SOX2+-pituitary stem/progenitor cells form two types of niches in this tissue: the marginal cell layer (MCL-niche) and the dense cell clusters scattering in the parenchyma (parenchymal-niche). However, little is known about the mechanisms and factors for regulating the pituitary stem/progenitor cell niches, as well as the functional differences between the two types of niches. Elucidation of the regulatory mechanisms in the niches might enable us to understand the cell regeneration system that acts in accordance with physiological demands in the adult pituitary. In this review, so as to reveal the regulatory mechanisms of the two types of niche, we summarize the regulatory factors and their roles in the adult rodent pituitary niches by focusing on three components: soluble factors, cell surface proteins and extracellular matrixes. PMID:26761002

  2. Regulatory System for Stem/Progenitor Cell Niches in the Adult Rodent Pituitary.

    PubMed

    Yoshida, Saishu; Kato, Takako; Kato, Yukio

    2016-01-01

    The anterior lobe of the pituitary gland is a master endocrine tissue composed of five types of endocrine cells. Although the turnover rate of pituitary endocrine cells is as low as about 1.6% per day, recent studies have demonstrated that Sex-determining region Y-box 2 (SOX2)⁺-cells exist as pituitary stem/progenitor cells in the adult anterior lobe and contribute to cell regeneration. Notably, SOX2⁺-pituitary stem/progenitor cells form two types of niches in this tissue: the marginal cell layer (MCL-niche) and the dense cell clusters scattering in the parenchyma (parenchymal-niche). However, little is known about the mechanisms and factors for regulating the pituitary stem/progenitor cell niches, as well as the functional differences between the two types of niches. Elucidation of the regulatory mechanisms in the niches might enable us to understand the cell regeneration system that acts in accordance with physiological demands in the adult pituitary. In this review, so as to reveal the regulatory mechanisms of the two types of niche, we summarize the regulatory factors and their roles in the adult rodent pituitary niches by focusing on three components: soluble factors, cell surface proteins and extracellular matrixes. PMID:26761002

  3. Mass spectrometric measurement of [beta]-endorphin and methionine enkephalin in human pituitaries. Tumors and post-mortem controls

    NASA Astrophysics Data System (ADS)

    Kusmierz, Jozef J.; Dass, Chhabil; Robertson, James T.; Desiderio, Dominic M.

    1991-12-01

    Two opioid neuropeptides, [beta]-endorphin (BE), which derives from the proopiomelanocortin (POMC) precursor, and methionine enkephalin (DE), which derives from proenkephalin A, were quantified with fast atom bombardment mass spectrometry (FAB-MS) in individual human pituitaries (post-mortem) and in tumor pituitaries (post-surgery) in a study to clarify the molecular processes that occur in tumor formation. FAB-MS in the multiple reaction monitoring mode linked the precursor ion (the MH+ ion) of the peptide with a fragment ion that was unique to each neuropeptide to increase significantly the molecular specificity of these quantitative analytical measurements. The ME was quantified as the intact pentapeptide, whereas BE1-31 was quantified via its tryptic fragment BE20-24 (NAIIK). Two corresponding stable isotope-incorporated peptides, [2H5-4Phe]-ME and [2H4-22Ile]-BE1-31,human respectively, were used as the internal standards. The amount of each neuropeptide quantified in control post-mortem pituitaries (n = 8) was 75.2 ± 29.6(s.e.m.) pmol ME mg-1 protein, and in the pituitary tumor samples (n = 5), 25.0 ± 7.6 pmol ME mg-1 protein and 36.0 ± 14.8 pmol BE mg-1 protein. The difference in the BE content between the control and tumor pituitaries was significant (p = 0.004), and reflected an aberrant metabolism of the POMC system in those human pituitary tumor tissues.

  4. Electrophoretic separation of cells and particles from rat pituitary and rat spleen

    NASA Technical Reports Server (NTRS)

    Hymer, Wesley C.

    1993-01-01

    There are 3 parts to the IML-2 TX-101 experiment. Part 1 is a pituitary cell culture experiment. Part 2 is a pituitary cell separation experiment using the Japanese free flow electrophoresis unit (FFEU). Part 3 is a pituitary secretory granule separation experiment using the FFEU. The objectives of this three part experiment are: (1) to determine the kinetics of production of biologically active growth hormone (GH) and prolactin (PRL) in rat pituitary GH and PRL cells in microgravity (micro-g); (2) to investigate three mechanisms by which a micro-g-induced lesion in hormone production may occur; and (3) to determine the quality of separations of pituitary cells and organelles by continuous flow electrophoresis (CFE) in micro-g under conditions where buoyancy-induced convection is eliminated.

  5. Effect of the growth hormone-secreting tumor StW5 on pituitary and adrenal gland function in rats.

    PubMed

    Coyne, M D; Alpert, L C; Harter, K C; Nunez, A

    1981-01-01

    A growth hormone-secreting tumor (StW5 was implanted into male rats and resulted in a tripling of adrenal weight concomitant with a 30% decrement in pituitary weight. Plasma concentrations of corticosterone in tumor-bearing (TB) rats were significantly elevated at rest or after ACTH injections or the stress of either anesthesia. The rise in plasma concentrations of corticosterone was due mainly to the large increment in adrenal size although a significant increase in adrenal responsiveness to ACTH was demonstrated in vitro. In addition, plasma corticosterone concentrations were higher in TB rats despite both a doubling of the blood volume and a 50% increase in liver capacity to metabolize corticosterone. Pituitary ACTH content was significantly lower in TB rats, but these pituitary glands could still release near-normal quantities of ACTH as shown both by in vitro incubations and adrenal corticosterone output following ether stress. PMID:6266940

  6. Extragonadal germ cell tumor presenting in a woman with systemic lupus erythematosus: a case report

    PubMed Central

    2010-01-01

    Introduction Germ cell tumor of the pituitary gland is a very rare occurrence. Case presentation We describe the case of a 28-year-old Malaysian Malay woman with lupus nephritis who complained of a three month headache and blurring of vision. She was found to have a pituitary mass, which was later proven to be a germ cell tumor. As of writing this case report, her disease is in remission. Conclusion The disruption of the pituitary gonad axis could affect the disease activity by reducing immunoregulatory control. PMID:20338049

  7. Conservative management of a pituitary tumor during pregnancy following induction of ovulation with gonadotropins.

    PubMed

    Jewelewicz, R; Zimmerman, E A; Carmel, P W

    1977-01-01

    Ovulation induced with human menopausal gonadotropin-human chorionic gonadotropin in a 27-year-old woman who had been amenorrheic for 7 years resulted in pregnancy. Although pretreatment neurologic evaluation was normal, significant loss of vision was found at 30 weeks' gestation, and a skull x-ray revealed enlargement and erosion of the sella turcica. As an attempt to delay surgery, 12 mg of dexamethasone daily arrested further visual deterioration, and the pregnancy continued uneventful for 36 weeks, when triplets were born. Five days after delivery the visual fields were normal. Trans-sphenoidal resection of a prolactin-secreting chromophobe adenoma of the pituitary was carried out 6 months later. It is suggested that when disturbance in visual perception due to a pituitary tumor occurs during pregnancy, a course of high-dose corticosteroids with frequent monitoring of visual fields and acuity might be tried before surgical intervention. Although further rapid deterioration in vision may dictate immediate surgical decompression, conservative management may result in stabilization, allowing the patient to carry the pregnancy to term and obviating the need for emergency surgery. PMID:832714

  8. EFFECTS OF CAGING DENSITY ON PITUITARY AND TESTICLE RELATED RESPONSES

    EPA Science Inventory

    Effects of caging density on pituitary and testicle related responses

    A significant negative correlation between the incidence of testicular interstitial cell tumors (ICT) and of pituitary tumors (PT) in control male F344 rats is reported associated with the number of ani...

  9. Contemporary issues in the evaluation and management of pituitary adenomas.

    PubMed

    Pekic, S; Stojanovic, M; Popovic, V

    2015-12-01

    Pituitary adenomas are common benign monoclonal neoplasms accounting for about 15% of intracranial neoplasms. Data from postmortem studies and imaging studies suggest that 1 of 5 individuals in the general population may have pituitary adenoma. Some pituitary adenomas (mainly microadenomas which have a diameter of less than 1 cm) are exceedingly common and are incidentally diagnosed on magnetic resonance imaging (MRI) performed for an unrelated reason (headache, vertigo, head trauma). Most microadenomas remain clinically occult and stable in size, without an increase in tumor cells and without local mass effects. However, some pituitary adenomas grow slowly, enlarge by expansion and become demarcated from normal pituitary (macroadenomas have a diameter greater than 1 cm). They may be clinically silent or secrete anterior pituitary hormones in excess such as prolactin, growth hormone (GH), or adrenocorticotropic hormone (ACTH) causing diseases like prolactinoma, acromegaly, Cushing's disease or rarely thyroid-stimulating hormone (TSH) or gonadotropins (LH, FSH). The incidence of the various subtypes of pituitary adenoma varies but the most common is prolactinoma. Clinically non-functioning pituitary adenomas (NFPAs), which do not secrete hormones often cause local mass symptoms and represent one-third of pituitary adenomas. Given the high prevalence of pituitary adenomas and their heterogeneity (different tumor subtypes), it is critical that clinicians have a thorough understanding of the potential abnormalities in pituitary function and prognostic factors for behavior of pituitary adenomas in order to timely implement specific treatment modalities. Regarding pathogenesis of these tumors genetics, epigenetics and signaling pathways are the focus of current research yet our understanding of pituitary tumorigenesis remains incomplete. Although several genes and signaling pathways have been identified as important factors in the development of pituitary tumors, current

  10. Identification of aromatase activity in rodent pituitary cell strains.

    PubMed

    Callard, G V; Petro, Z; Tashjian, A H

    1983-07-01

    To date, biochemical evidence has been presented for hypophysial aromatization in only one species, a teleost fish, although the pituitary glands of several mammals have been reported to be aromatase negative. To reinvestigate this problem, established clonal strains of rodent pituitary cells (GH3, GH4C1, and AtT20/D16) were incubated at 37 C for 6-48 h in serum-less medium containing [7-3H]androstenedione. Radiolabeled metabolites were isolated by solvent extraction, thin layer chromatography, and phenolic partition. The authenticity of the estrogenic products in both cells and incubation medium was verified by methylation and recrystallization to constant specific activity. Measurement of androgen metabolites was also validated by recrystallization of selected samples. Authentic estrone and 17 beta-estradiol were identified in cultures of the two PRL- and GH-secreting clones, and there were strain differences in the quantity of estrogen produced (GH3 greater than GH4C1). Under the same conditions, aromatization was not detectable in the ACTH-secreting line (AtT20/D16). A time-yield analysis of androgen metabolism in GH4C1 cells showed that aromatization was linear for 12 h after labeling, but that substrate was diverted mainly to 5 alpha-reducing pathways. Large amounts of highly polar metabolites accumulated 24 and 48 h after the addition of [3H]androgen, and subsequent hydrolysis revealed that these were sulfo- and glucuronoconjugates. The metabolic fate of estrogen in GH4C1 cultures was investigated indirectly by adding a radioinert estrone trap together with the radiolabeled androgen substrate and was also tested in separate cultures by adding [3H]estrone and [3H]estradiol directly. Although the two estrogens were interconverted, there was no evidence that formed or added estrogen was extensively metabolized or conjugated. We conclude that the expression of aromatase activity in hypophysial cells is not a property of all transformed lines but may be dictated

  11. Human rhabdomyosarcoma cells express functional pituitary and gonadal sex hormone receptors: Therapeutic implications.

    PubMed

    Poniewierska-Baran, Agata; Schneider, Gabriela; Sun, Wenyue; Abdelbaset-Ismail, Ahmed; Barr, Frederic G; Ratajczak, Mariusz Z

    2016-05-01

    Evidence has accumulated that sex hormones play an important role in several types of cancer. Because they are also involved in skeletal muscle development and regeneration, we were therefore interested in their potential involvement in the pathogenesis of human rhabdomyosarcoma (RMS), a skeletal muscle tumor. In the present study, we employed eight RMS cell lines (three fusion positive and five fusion negative RMS cell lines) and mRNA samples obtained from RMS patients. The expression of sex hormone receptors was evaluated by RT-PCR and their functionality by chemotaxis, adhesion and direct cell proliferation assays. We report here for the first time that follicle-stimulating hormone (FSH) and luteinizing hormone (LH) receptors are expressed in established human RMS cell lines as well as in primary tumor samples isolated from RMS patients. We also report that human RMS cell lines responded both to pituitary and gonadal sex hormone stimulation by enhanced proliferation, chemotaxis, cell adhesion and phosphorylation of MAPKp42/44 and AKT. In summary, our results indicate that sex hormones are involved in the pathogenesis and progression of RMS, and therefore, their therapeutic application should be avoided in patients that have been diagnosed with RMS. PMID:26983595

  12. Human rhabdomyosarcoma cells express functional pituitary and gonadal sex hormone receptors: Therapeutic implications

    PubMed Central

    PONIEWIERSKA-BARAN, AGATA; SCHNEIDER, GABRIELA; SUN, WENYUE; ABDELBASET-ISMAIL, AHMED; BARR, FREDERIC G.; RATAJCZAK, MARIUSZ Z.

    2016-01-01

    Evidence has accumulated that sex hormones play an important role in several types of cancer. Because they are also involved in skeletal muscle development and regeneration, we were therefore interested in their potential involvement in the pathogenesis of human rhabdomyosarcoma (RMS), a skeletal muscle tumor. In the present study, we employed eight RMS cell lines (three fusion positive and five fusion negative RMS cell lines) and mRNA samples obtained from RMS patients. The expression of sex hormone receptors was evaluated by RT-PCR and their functionality by chemotaxis, adhesion and direct cell proliferation assays. We report here for the first time that follicle-stimulating hormone (FSH) and luteinizing hormone (LH) receptors are expressed in established human RMS cell lines as well as in primary tumor samples isolated from RMS patients. We also report that human RMS cell lines responded both to pituitary and gonadal sex hormone stimulation by enhanced proliferation, chemotaxis, cell adhesion and phosphorylation of MAPKp42/44 and AKT. In summary, our results indicate that sex hormones are involved in the pathogenesis and progression of RMS, and therefore, their therapeutic application should be avoided in patients that have been diagnosed with RMS. PMID:26983595

  13. A double pituitary adenoma presenting as a prolactin-secreting tumor with partial response to medical therapy. Case report.

    PubMed

    Coiré, Claire I; Smyth, Harley S; Rosso, Dominic; Horvath, Eva; Kovacs, Kalman

    2010-06-01

    Double pituitary adenomas are difficult to recognize pre-operatively as only a single mass may be appreciated on imaging. We present herein a giant prolactin-secreting pituitary adenoma in a middle-aged man that had responded partially to dopamine agonist therapy. The excised specimen demonstrated a double adenoma. The prolactin-producing one displayed the expected morphological changes resulting from medical therapy, while the other, a gonadotroph adenoma, did not. The failure of tumor shrinkage can be attributed to the presence of a double adenoma, a previously unreported cause of failure of medical therapy in prolactinoma. PMID:20058099

  14. Canine mast cell tumors.

    PubMed

    Macy, D W

    1985-07-01

    Despite the fact that the mast cell tumor is a common neoplasm of the dog, we still have only a meager understanding of its etiology and biologic behavior. Many of the published recommendations for treatment are based on opinion rather than facts derived from careful studies and should be viewed with some skepticism. Because of the infrequent occurrence of this tumor in man, only a limited amount of help can be expected from human oncologists; therefore, burden of responsibility for progress in predicting behavior and developing treatment effective for canine mast cell tumors must fall on the shoulders of the veterinary profession. PMID:3929444

  15. Brain tumor stem cells.

    PubMed

    Palm, Thomas; Schwamborn, Jens C

    2010-06-01

    Since the end of the 'no-new-neuron' theory, emerging evidence from multiple studies has supported the existence of stem cells in neurogenic areas of the adult brain. Along with this discovery, neural stem cells became candidate cells being at the origin of brain tumors. In fact, it has been demonstrated that molecular mechanisms controlling self-renewal and differentiation are shared between brain tumor stem cells and neural stem cells and that corruption of genes implicated in these pathways can direct tumor growth. In this regard, future anticancer approaches could be inspired by uncovering such redundancies and setting up treatments leading to exhaustion of the cancer stem cell pool. However, deleterious effects on (normal) neural stem cells should be minimized. Such therapeutic models underline the importance to study the cellular mechanisms implicated in fate decisions of neural stem cells and the oncogenic derivation of adult brain cells. In this review, we discuss the putative origins of brain tumor stem cells and their possible implications on future therapies. PMID:20370314

  16. Cell types in the pituitary of the roach, Rutilus rutilus (L.), (Teleostei).

    PubMed Central

    Jafri, S I; Ensor, D M

    1980-01-01

    The pituitary of roach, Rutilus rutilus (L.), is pear-shaped and situated in the sella turcica. It is characterised by a large pars nervosa, which penetrates deep into the other regions, splitting the proximal pars distalis. Spatial localisation of nerve fibre types and glandular cell types occurs. Using a variety of staining techniques six glandular cell types have been localised and their distribution is disucssed in relation to those of the other teleost pituitaries. PMID:6159340

  17. Comparative immunohistochemical study of stellate cells in normal canine and equine adenohypophyses and in pituitary tumours.

    PubMed

    Méndez, A; Martín de las Mulas, J; Bautista, M J; Chacón, F; Millán, Y; Fondevila, D; Pumarola, M

    1998-01-01

    The presence and distribution of S100 protein (alpha and beta subunits), cytokeratin polypeptides, glial fibrillary acidic protein, neurofilaments, vimentin, neuron specific enolase, synaptophysin, HLA class II DR antigen, and pituitary hormones (prolactin, adrenocorticotropic hormone and human chorionic gonadotrophin) in stellate cells were studied immunohistochemically in four normal canine pituitary glands, five canine pituitary adenomas, two canine pituitary carcinomas and two equine pituitary adenomas (with surrounding normal glandular tissue). Stellate cells of the pars distalis and pars intermedia of canine and equine adenohypophyses showed a strong reaction with antibodies against S100 protein subunits alpha and beta. They also reacted with antibody against high and low molecular weight cytokeratins, but not with those against other intermediate filament proteins, neuroendocrine markers, the HLA-class II DR antigen or the pituitary hormones. Other populations of cells expressing both subunits of the S100 protein were polygonal cells of the pars distalis of the adenohypophysis (horse) and marginal epithelial cells of the pars intermedia of the adenohypophysis (dog and horse). Some pituitary tumours had S100-immunoreactive cells with a distribution of alpha and beta subunits that differed between the two species. Some canine tumours (one adenoma and one carcinoma) expressed only the alpha subunit, but both of the equine adenomas expressed alpha and beta protein subunits. Some of the S100-immunoreactive tumour cells reacted with RCK-102 (cytokeratins 5+8) antibody in the dog but not in the horse. The results suggested that canine and equine stellate cells of the adenohypophysis are more closely related to epithelial than to glial cells, as is the case in cattle, sheep and goats but not human beings or mice. No subpopulation of cells of bone marrow origin could be identified among canine stellate cells, as they lack MHC class II antigen. The results also

  18. Pituitary Apoplexy.

    PubMed

    Briet, Claire; Salenave, Sylvie; Bonneville, Jean-François; Laws, Edward R; Chanson, Philippe

    2015-12-01

    Pituitary apoplexy, a rare clinical syndrome secondary to abrupt hemorrhage or infarction, complicates 2%-12% of pituitary adenomas, especially nonfunctioning tumors. Headache of sudden and severe onset is the main symptom, sometimes associated with visual disturbances or ocular palsy. Signs of meningeal irritation or altered consciousness may complicate the diagnosis. Precipitating factors (increase in intracranial pressure, arterial hypertension, major surgery, anticoagulant therapy or dynamic testing, etc) may be identified. Corticotropic deficiency with adrenal insufficiency may be life threatening if left untreated. Computed tomography or magnetic resonance imaging confirms the diagnosis by revealing a pituitary tumor with hemorrhagic and/or necrotic components. Formerly considered a neurosurgical emergency, pituitary apoplexy always used to be treated surgically. Nowadays, conservative management is increasingly used in selected patients (those without important visual acuity or field defects and with normal consciousness), because successive publications give converging evidence that a wait-and-see approach may also provide excellent outcomes in terms of oculomotor palsy, pituitary function and subsequent tumor growth. However, it must be kept in mind that studies comparing surgical approach and conservative management were retrospective and not controlled. PMID:26414232

  19. Identification and enrichment of colony-forming cells from the adult murine pituitary

    SciTech Connect

    Lepore, D.A.; Roeszler, K.; Wagner, J.; Ross, S.A.; Bauer, K.; Thomas, P.Q. , E-Mail: paul.thomas@mcri.edu.au

    2005-08-01

    Stem and progenitor cells have been identified in many adult tissues including bone marrow, the central nervous system, and skin. While there is direct evidence to indicate the activity of a progenitor cell population in the pituitary gland, this putative subpopulation has not yet been identified. Herein we describe the isolation and characterization of a novel clonogenic cell type in the adult murine pituitary, which we have termed Pituitary Colony-Forming Cells (PCFCs). PCFCs constitute 0.2% of pituitary cells, and generate heterogeneous colonies from single cells. PCFCs exhibit variable proliferative potential, and may exceed 11 population doublings in 14 days. Enrichment of PCFCs to 61.5-fold with 100% recovery can be obtained through the active uptake of the fluorescent dipeptide, {beta}-Ala-Lys-N{epsilon}-AMCA. PCFCs are mostly contained within the large, agranular subpopulation of AMCA{sup +} cells, and constitute 28% of this fraction, corresponding to 140.5-fold enrichment. Interestingly, the AMCA{sup +} population contains rare cells that are GH{sup +} or PRL{sup +}. GH{sup +} cells were also identified in PCFC single cell colonies, suggesting that PCFCs have the potential to differentiate into GH{sup +} cells. Together, these data show that the pituitary contains a rare clonogenic population which may correspond to the somatotrope/lactotrope progenitors suggested by previous experiments.

  20. Testicular germ cell tumors.

    PubMed

    Looijenga, Leendert H J

    2014-02-01

    Human germ cell tumors are of interest because of their epidemiology, clinical behavior and pathobiology. Histologically, they are subdivided into various elements, with similarities to embryogenesis. Recent insights resulted in a division of five types of human germ cell tumors. In the context of male germ cells, three are relevant; Type I: teratomas and yolk sac tumors of neonates and infants; Type II: seminomas and nonseminomas of (predominantly) adolescents and adults; and Type III: spermatocytic seminomas of the elderly. Recent studies led to significant increases in understanding of the parameters involved in the earliest pathogenetic steps of human germ cells tumors, in particularly the seminomas and nonseminomas (Type II). In case of a disturbed gonadal physiology, either due to the germ cell itself, or the micro-environment, embryonic germ cells during a specific window of sensitization can be blocked in their maturation, resulting in carcinoma in situ or gonadoblastoma, the precursors of seminomas and nonseminomas. The level of testicularization of the gonad determines the histological composition of the precursor. These insights will allow better definition of individuals at risk to develop a germ cell malignancy, with putative preventive measurements, and allow better selection of scientific approaches to elucidate the pathogenesis. PMID:24683949

  1. Altered glycosylation in tumor cells

    SciTech Connect

    Reading, C.L. ); Hakomori, S. ); Marcus, D.M. )

    1988-01-01

    This book contains the proceeding on the following: Glycoconjugates of normal and tumor cells; Glycosyltransferases in normal and neoplastic cells; Mammalian lectins of normal tissues and tumor cells; and Immune recognition of carbohydrates and clinical applications.

  2. Pituitary carcinoma with endolymphatic sac metastasis.

    PubMed

    Balili, Irida; Sullivan, Steven; Mckeever, Paul; Barkan, Ariel

    2014-06-01

    Pituitary carcinoma is characterized by the presence of a metastatic lesion(s) in a location non-contiguous with the original pituitary tumor. The mechanism(s) of malignant transformation are not known. A 15 year-old male was diagnosed in 1982 with a pituitary macroadenoma and acromegaly (random GH 67 ng/ml and no suppression by oral glucose). His prolactin was normal between 18 and 23 ng/ml. Transcranial resection in July 1983 was followed by radiation therapy. The tumor was immunopositive for GH and prolactin. The proliferation MIB-1 index was 0-1%. With aqueous Octreotide 100 mcg 4× daily both GH and IGF-1 became normal. The patient was lost to follow-up and was treated by his local physician. In 2001, his IGF-1 level was 1271 ng/ml, and his random GH was 1.8-2.4 ng/ml by ILMA despite progressive increase in the dose of Sandostatin LAR to 140 mg/month in divided doses. Prolactin remained normal or minimally increased between 15 and 25 ng/ml. In 2009 he was diagnosed with the tumor in the location of left endolymphatic sac. Histological examination showed low grade pituitary carcinoma strongly immunopositive for prolactin but negative for GH. MIB-1 antibody labeled 0-5% cells. In 2012 endoscopic resection of the pituitary tumor remnant was attempted. Immunohistochemical stains were strongly immunopositive for both prolactin and GH, similar to his original pituitary tumor. The MIB-1 proliferation index was low from 0 to 1%. To our knowledge this is the first case of pituitary carcinoma in the endolymphatic sac region. The dichotomy between the cell population of the pituitary lesion (GH/prolactin producing) and the metastasis (purely prolactin-producing) may suggest that the metastatic pituitary lesion derived from a clone distinct from the original one. PMID:23645293

  3. Tumor heterogeneity and circulating tumor cells.

    PubMed

    Zhang, Chufeng; Guan, Yan; Sun, Yulan; Ai, Dan; Guo, Qisen

    2016-05-01

    In patients with cancer, individualized treatment strategies are generally guided by an analysis of molecular biomarkers. However, genetic instability allows tumor cells to lose monoclonality and acquire genetic heterogeneity, an important characteristic of tumors, during disease progression. Researchers have found that there is tumor heterogeneity between the primary tumor and metastatic lesions, between different metastatic lesions, and even within a single tumor (either primary or metastatic). Tumor heterogeneity is associated with heterogeneous protein functions, which lowers diagnostic precision and consequently becomes an obstacle to determining the appropriate therapeutic strategies for individual cancer patients. With the development of novel testing technologies, an increasing number of studies have attempted to explore tumor heterogeneity by examining circulating tumor cells (CTCs), with the expectation that CTCs may comprehensively represent the full spectrum of mutations and/or protein expression alterations present in the cancer. In addition, this strategy represents a minimally invasive approach compared to traditional tissue biopsies that can be used to dynamically monitor tumor evolution. The present article reviews the potential efficacy of using CTCs to identify both spatial and temporal tumor heterogeneity. This review also highlights current issues in this field and provides an outlook toward future applications of CTCs. PMID:26902424

  4. The genetics of pituitary adenomas.

    PubMed

    Vandeva, Silvia; Jaffrain-Rea, Marie-Lise; Daly, Adrian F; Tichomirowa, Maria; Zacharieva, Sabina; Beckers, Albert

    2010-06-01

    Pituitary adenomas are one of the most frequent intracranial tumors with a prevalence of clinically-apparent tumors close to 1:1000 of the general population. They are clinically significant because of hormone overproduction and/or tumor mass effects in addition to the need for neurosurgery, medical therapies and radiotherapy. The majority of pituitary adenomas have a sporadic origin with recognized genetic mutations seldom being found; somatotropinomas are an exception, presenting frequent somatic GNAS mutations. In this and other phenotypes, tumorigenesis could possibly be explained by altered function of genes implicated in cell cycle regulation, growth factors or their receptors, cell-signaling pathways, specific hormonal factors or other molecules with still unclear mechanisms of action. Genetic changes, such as allelic loss or gene amplification, and epigenetic changes, usually by promoter methylation, have been implicated in abnormal gene expression, but alternative mechanisms may be present. Familial cases of pituitary adenomas represent 5% of all pituitary tumors. MEN1 mutations cause multiple endocrine neoplasia type 1 (MEN1), while the Carney complex (CNC) is characterized by mutations in the protein kinase A regulatory subunit-1alpha (PRKAR1A) gene or changes in a locus at 2p16. Recently, a MEN1-like condition, MEN4, was found to be related to mutations in the CDKN1B gene. The clinical entity of familial isolated pituitary adenomas (FIPA) is characterized by genetic defects in the aryl hydrocarbon receptor interacting protein (AIP) gene in about 15% of all kindreds and 50% of homogenous somatotropinoma families. Identification of familial cases of pituitary adenomas is important as these tumors may be more aggressive than their sporadic counterparts. PMID:20833337

  5. Gamma-Secretase Inhibitor RO4929097 in Treating Young Patients With Relapsed or Refractory Solid Tumors, CNS Tumors, Lymphoma, or T-Cell Leukemia

    ClinicalTrials.gov

    2014-11-04

    Childhood Atypical Teratoid/Rhabdoid Tumor; Childhood Central Nervous System Choriocarcinoma; Childhood Central Nervous System Germinoma; Childhood Central Nervous System Mixed Germ Cell Tumor; Childhood Central Nervous System Teratoma; Childhood Central Nervous System Yolk Sac Tumor; Childhood Choroid Plexus Tumor; Childhood Craniopharyngioma; Childhood Ependymoblastoma; Childhood Grade I Meningioma; Childhood Grade II Meningioma; Childhood Grade III Meningioma; Childhood Infratentorial Ependymoma; Childhood Medulloepithelioma; Childhood Mixed Glioma; Childhood Oligodendroglioma; Childhood Supratentorial Ependymoma; Gonadotroph Adenoma; Pituitary Basophilic Adenoma; Pituitary Chromophobe Adenoma; Pituitary Eosinophilic Adenoma; Prolactin Secreting Adenoma; Recurrent Childhood Acute Lymphoblastic Leukemia; Recurrent Childhood Anaplastic Large Cell Lymphoma; Recurrent Childhood Brain Stem Glioma; Recurrent Childhood Central Nervous System Embryonal Tumor; Recurrent Childhood Cerebellar Astrocytoma; Recurrent Childhood Cerebral Astrocytoma; Recurrent Childhood Ependymoma; Recurrent Childhood Grade III Lymphomatoid Granulomatosis; Recurrent Childhood Large Cell Lymphoma; Recurrent Childhood Lymphoblastic Lymphoma; Recurrent Childhood Medulloblastoma; Recurrent Childhood Pineoblastoma; Recurrent Childhood Small Noncleaved Cell Lymphoma; Recurrent Childhood Spinal Cord Neoplasm; Recurrent Childhood Subependymal Giant Cell Astrocytoma; Recurrent Childhood Supratentorial Primitive Neuroectodermal Tumor; Recurrent Childhood Visual Pathway and Hypothalamic Glioma; Recurrent Childhood Visual Pathway Glioma; Recurrent Pituitary Tumor; Recurrent/Refractory Childhood Hodgkin Lymphoma; T-cell Childhood Acute Lymphoblastic Leukemia; T-cell Large Granular Lymphocyte Leukemia; TSH Secreting Adenoma; Unspecified Childhood Solid Tumor, Protocol Specific

  6. Relevance of pituitary aromatase and estradiol on the maintenance of the population of prolactin-positive cells in male mice.

    PubMed

    García-Barrado, María José; Blanco, Enrique J; Catalano-Iniesta, Leonardo; Sanchez-Robledo, Virginia; Iglesias-Osma, María Carmen; Carretero-Hernández, Marta; Rodríguez-Cobos, Javier; Burks, Deborah Jane; Carretero, José

    2016-07-01

    In previous studies we demonstrated the expression of aromatase in pituitary cells. This expression is gender related, and is also associated with the presence of prolactinomas. To ascertain the relevance of aromatase in modulating the populations of prolactin-positive pituitary cells an immunocytochemical and morphometric study of prolactin-positive pituitary cells was carried out using the pituitary glands of adult male and female aromatase-knockout (ArKO) mice. Additionally has been determined if pituitary aromatase is involved in a gender-linked differentiated regulation of the prolactin-producing pituitary cells. Compared to wild-type mice, the knockout animals of both genders showed a significant decrease (p<0.01) in the cellular and nuclear areas of their prolactin cells, as well as in the percentages of the prolactin-positive cells and the proliferating prolactin cells. Our results suggest that estradiol is responsible for the maintenance of the population of prolactin cell in males and, so as not to disturb the endocrine reproductive environment, estradiol is synthesized inside the pituitary by circulating testosterone via means of aromatase P450, which acts in paracrine way. This new role for pituitary aromatase may well explain the previous findings establishing that the pituitary expression of aromatase is higher in males than in females, and the association between the development of prolactinomas and the increased expression of aromatase in tumours. PMID:27046736

  7. Tumor cell intravasation.

    PubMed

    Chiang, Serena P H; Cabrera, Ramon M; Segall, Jeffrey E

    2016-07-01

    The process of entering the bloodstream, intravasation, is a necessary step in the development of distant metastases. The focus of this review is on the pathways and molecules that have been identified as being important based on current in vitro and in vivo assays for intravasation. Properties of the vasculature which are important for intravasation include microvessel density and also diameter of the vasculature, with increased intravasation correlating with increased vessel diameter in some tumors. TGFB signaling can enhance intravasation at least in part through induction of EMT, and we discuss other TGFB target genes that are important for intravasation. In addition to TGFB signaling, a number of studies have demonstrated that activation of EGF receptor family members stimulates intravasation, with downstream signaling through PI3K, N-WASP, RhoA, and WASP to induce invadopodia. With respect to proteases, there is strong evidence for contributions by uPA/uPAR, while the roles of MMPs in intravasation may be more tumor specific. Other cells including macrophages, fibroblasts, neutrophils, and platelets can also play a role in enhancing tumor cell intravasation. The technology is now available to interrogate the expression patterns of circulating tumor cells, which will provide an important reality check for the model systems being used. With a better understanding of the mechanisms underlying intravasation, the goal is to provide new opportunities for improving prognosis as well as potentially developing new treatments. PMID:27076614

  8. Immunohistochemical characterization of chicken pituitary cells containing the vasotocin VT2 receptor.

    PubMed

    Jurkevich, Alexander; Berghman, Luc R; Cornett, Lawrence E; Kuenzel, Wayne J

    2008-08-01

    Research in mammals has demonstrated a variety of regulatory effects of vasopressin and oxytocin on endocrine functions of the anterior pituitary gland. Less evidence is available regarding the hypophysiotropic action of arginine vasotocin (AVT) comprising vasopressic and oxytocic activities in birds. Some hypophysiotropic effects of AVT may result from its interactions with brain circuits controlling pituitary functions, whereas others are caused by its direct affect on pituitary cells. Use of an antiserum to the vasotocin receptor VT2 (VT2R) has revealed numerous immunoreactive cells in the anterior pituitary gland of the chicken. The objective of the present study has been to identify endocrine phenotypes of chicken pituitary cells containing VT2R by means of immunohistochemical labeling. VT2R immunoreactivity has been found in all cells immunoreactive for adrenocorticotropin and alpha-melanotropin. Approximately 10% of labeled lactotropes are also immunoreactive for VT2R and lie around the anatomical boundary dividing the cephalic and caudal lobes. In both corticotropes/melanotropes and lactotropes, immunoreactive VT2R is present in a narrow layer outlining cell bodies. Immunoreactive VT2R is not found in gonadotropes, thyrotropes, or somatotropes. These results provide evidence for the important role of VT2Rs in mediating effects of AVT on endocrine secretion from corticotropes and, partially, from lactotropes. PMID:18548280

  9. [Mediastinal germ cell tumors].

    PubMed

    Bremmer, F; Ströbel, P

    2016-09-01

    The mediastinum is among the most frequent anatomic region in which germ cell tumors (GCT) arise, second only to the gonads. Mediastinal GCT (mGCT) account for 16 % of all mediastinal neoplasms. Although the morphology and (according to all available data) the molecular genetics of mediastinal and gonadal GCT are identical, a number of unique aspects exist. There is a highly relevant bi-modal age distribution. In pre-pubertal children of both sexes, mGCT consist exclusively of teratomas and yolk sac tumors. The prognosis is generally favorable with modern treatment. In post-pubertal adults, virtually all patients with malignant mGCT are males; the prognosis is more guarded and depends (among other factors) on the histological GCT components and is similar to GCT in other organs. So-called somatic type malignancies (i. e. clonally related, non-germ cell neoplasias arising in a GCT) are much more frequent in mGCT than in other organs, and the association between mediastinal yolk sac tumors and hematological malignancies, such as myelodysplasias and leukemias, is unique to mediastinal tumors. The prognosis of GCT with somatic type malignancies is generally dismal. PMID:27491549

  10. Effect of Hypoxia on DDR1 Expression in Pituitary Adenomas

    PubMed Central

    Li, Shouchun; Zhang, Zhiwen; Xue, Jinghui; Guo, Xiaoming; Liang, Shuli; Liu, Aijun

    2015-01-01

    Background Pituitary adenoma is a common intracranial tumor in neurosurgery. Some pituitary adenomas have the characteristics of invasive growth make them unable to be removed completely by surgery leading to easy relapse. Discoidin domain receptor l (DDR1) is a new kind of tyrosine kinase receptor on the cell surface. DDR1 can be activated by tumor microenvironment signal in tumorigenesis, increasing MMP-2/9 expression and promoting the invasive ability of tumor cells. Anoxia can promote tumor growth and metastasis. This study investigated the impact of anoxic environment DDR1 expression in pituitary adenoma. Material/Methods A primary hypoxia pituitary adenoma cell model was established and treated with DDR1 inhibitor nilotinib. Real-time PCR and Western blot were used to detect DDR1 mRNA and protein expression. ELISA was used to detect MMP-2/9 changes. MTT method was used to detect pituitary adenoma cell proliferation. We used a transwell chamber to determine pituitary adenoma cell invasion ability. Results DDR1 mRNA and protein were significantly overexpressed under hypoxia (P<0.05). MMP-2 and MMP-9 expression was obviously increased in supernatant (P<0.05). Pituitary adenoma cell proliferation and invasive ability improved markedly under hypoxia (P<0.05). Nilotinib could reduce DDR1 expression, decrease MMP-2 and MMP-9 expression, and inhibit pituitary adenoma cells proliferation and invasion. Conclusions Hypoxia can increase DDR1 expression in pituitary adenoma cells, leading to improved MMP-2 and MMP-9 secretion, and promoting pituitary adenoma cell proliferation and invasion. PMID:26286316

  11. Regulation of the pituitary tumor transforming gene by insulin-like-growth factor-I and insulin differs between malignant and non-neoplastic astrocytes

    SciTech Connect

    Chamaon, Kathrin; Kirches, Elmar; Kanakis, Dimitrios; Braeuninger, Stefan; Dietzmann, Knut; Mawrin, Christian . E-mail: christian.mawrin@medizin.uni-magdeburg.de

    2005-05-27

    The reasons for overexpression of the oncogene pituitary tumor transforming gene (PTTG) in tumors are still not fully understood. A possible influence of the insulin-like growth factor I (Igf-I) may be of interest, since enhanced Igf-I signalling was reported in various human tumors. We examined the influence of Igf-I and insulin on PTTG expression in human astrocytoma cells in comparison to proliferating non-neoplastic rat embryonal astrocytes. PTTG mRNA expression and protein levels were increased in malignant astrocytes treated with Igf-I or insulin, whereas in rat embryonic astrocytes PTTG expression and protein levels increased only when cells were exposed to Igf-I. Enhanced transcription did not occur after treatment with inhibitors of phosphoinositol-3-kinase (PI3K) and mitogen-activated protein kinase (MAPK), blocking the two basic signalling pathways of Igf-I and insulin. In addition to this transcriptional regulation, both kinases directly bind to PTTG, suggesting a second regulatory route by phosphorylation. However, the interaction of endogenous PTTG with MAPK and PI3K, as well as PTTG phosphorylation were independent from Igf-I or insulin. The latter results were also found in human testis, which contains high PTTG levels as well as in nonneoplastic astrocytes. This suggest, that PI3K and MAPK signalling is involved in PTTG regulation not only in malignant astrocytomas but also in non-tumorous cells.

  12. Loss of function of the tumor suppressor DKC1 perturbs p27 translation control and contributes to pituitary tumorigenesis

    PubMed Central

    Bellodi, Cristian; Krasnykh, Olya; Haynes, Nikesha; Theodoropoulou, Marily; Peng, Guang; Montanaro, Lorenzo; Ruggero, Davide

    2010-01-01

    Mutations in DKC1, encoding for dyskerin a pseudouridine synthase that modifies rRNA and regulates telomerase activity, are associated with ribosomal dysfunction and increased cancer susceptibility in the human syndrome, X-linked Dyskeratosis Congenita (X-DC). In a mouse model for X-DC, impairments in DKC1 function affected translation of specific mRNAs harboring internal ribosomal entry site (IRES) elements, including the tumor suppressor, p27. However, how this translational deregulation contributes to tumor initiation and progression remains poorly understood. Here, we report that impairment in p27 IRES-mediated translation, due to decreased levels of DKC1 activity markedly increases spontaneous pituitary tumorigenesis in p27 heterozygous mice. Using a new bioluminescent mouse model, we monitor p27 translation in vivo and show that p27 IRES-mediated translation is reduced in the pituitary of DKC1 hypomorphic mice (DKC1m). Furthermore, we show that DKC1 has a critical role in regulating the assembly of the 48S translational pre-initiation complex mediated by the p27 IRES-element. An analysis of human tumors identified a novel mutation of DKC1 (DKC1S485G) in a human pituitary adenoma. We show that this specific amino acid substitution significantly alters DKC1 stability/pseudouridylation activity, and this correlates with reductions in p27 protein levels. Furthermore, DKC1S485G mutation does not alter telomerase RNA levels. Altogether, these findings demonstrate that genetic alterations in DKC1 can contribute to tumorigenesis associated with somatic cancers and establish a critical role for DKC1 in tumor suppression, at least in part, through translational control of p27. PMID:20587522

  13. Pregnancy and pituitary adenomas.

    PubMed

    Glezer, Andrea; Jallad, Raquel S; Machado, Marcio C; Fragoso, Maria C; Bronstein, Marcello D

    2016-09-01

    Infertility is frequent in patients harboring pituitary adenomas. The mechanisms involved include hypogonadism secondary to hormonal hypersecretion (prolactin, growth hormone and cortisol), stalk disconnection and pituitary damage. With the improvement of clinical and surgical treatment, pregnancy in women harboring pituitary adenomas turned into a reality. Pituitary hormonal hyper- and hyposecretion influences pregnancy outcomes, as well as pregnancy can interfere on pituitary tumors, especially in prolactinomas. We review literature about specific follow-up and management in pregnant women harboring prolactinomas, acromegaly, or Cushings disease and the impact of clinical and surgical treatment on each condition. PMID:26977888

  14. Exposure of tilapia pituitary cells to saponins: insight into their mechanism of action.

    PubMed

    Levavi-Sivan, Berta; Hedvat, Rachel; Kanias, Tamir; Francis, George; Becker, Klaus; Kerem, Zohar

    2005-01-01

    Cell permeation and durable effects of triterpenoidal saponin preparations from soybean (SbS), Quillaja saponaria Molina (QsS) and Gypsophila paniculata (GypS), were studied. A concentration-dependent change in hemolysis rates was observed when cells were incubated with QsS or GypS, but not with SbS. Dose dependence was also observed for the leakage of lactate dehydrogenase (LDH; MW 142,000) and of Luteinizing Hormone (LH; MW 35,000) from tilapia pituitary dispersed cells. Exposure of pituitary fragments to a combination of GnRH and GypS or QsS, resulted in a significantly high release of LH. GypS were shown to be more potent in inducing hemolysis of human RBC's and LH release from tilapia pituitary fragments. Interestingly, tilapia pituitary fragments treated with QsS were able to secrete LH in a characteristic manner, in response to a second Gonadotropin Releasing Hormone (GnRH) pulse, while fragments exposed to GypS did not respond to the second hormone pulse. The rapid recovery of pituitary fragments after the removal of QsS, may suggest a rearrangement of membranes rather than pore formation as the mechanism of action of QsS. Understanding the structural features underlying the reversible rearrangement of membranes and the lack of hemolysing activity by specific saponins may lead to the development of novel bioactive drugs. PMID:15792626

  15. Dentinogenic ghost cell tumor

    PubMed Central

    Bafna, Sweety Sagarmal; Joy, Tabita; Tupkari, Jagdish Vishnu; Landge, Jayant Shivaji

    2016-01-01

    Dentinogenic ghost cell tumor (DGCT) is a rare, odontogenic neoplasm which is considered to be a solid variant of calcifying odontogenic cyst (COC) with locally aggressive behavior. It accounts for only 2–14% of all COCs. To the best of our knowledge, only 88 cases of DGCT have been reported in the literature from 1968 to 2014. Herewith, we report a case of DGCT in a 68-year-old male patient with clinical presentation as a soft tissue growth over alveolar ridge and histopathologically characterized by ameloblastomatous epithelium, abundance of eosinophilic material and ghost cells. PMID:27194885

  16. Cell-to-cell communication in the anterior pituitary: evidence for gap junction-mediated exchanges between endocrine cells and folliculostellate cells.

    PubMed

    Morand, I; Fonlupt, P; Guerrier, A; Trouillas, J; Calle, A; Remy, C; Rousset, B; Munari-Silem, Y

    1996-08-01

    The ability of rat anterior pituitary cells to communicate through gap junctions (GJ) was studied using a fluorescent molecule, Lucifer Yellow (LY), which freely passes through GJ channels. The probe was introduced into the cell cytoplasm by using either the cut-end loading method on intact tissue, or cell microinjection on cultured cells. The identification of communicating cells was performed by immunofluorescence labeling of specific hormones in endocrine cells and of S100 protein in folliculostellate (FS) cells. Rat anterior pituitary cells in their physiological organization, i.e. in the intact tissue, exhibited a high level of coupling through GJ. LY-labeled cells were found up to 300-microns apart from its site of introduction. The communicating cells were primarily PRL cells, GH cells, and FS cells. Only a few LH, TSH, and ACTH cells were labeled with LY. Anterior pituitary cells, isolated from the rat tissue by mild protease treatment and cultured for 3 days, reestablished functional GJ as demonstrated by microinjection of LY into individual cells. By immunolabeling of specific hormones and/or S100 protein, we found a GJ coupling between FS cells, and between FS cells and endocrine cells, including PRL cells. The communication between FS cells was by far the most frequent. In conclusion, we demonstrate the presence of functional GJ between anterior pituitary cells of the same type and between anterior pituitary cells having distinct differentiated functions. PMID:8754762

  17. The dynamics underlying pseudo-plateau bursting in a pituitary cell model.

    PubMed

    Teka, Wondimu; Tabak, Joël; Vo, Theodore; Wechselberger, Martin; Bertram, Richard

    2011-11-01

    Pituitary cells of the anterior pituitary gland secrete hormones in response to patterns of electrical activity. Several types of pituitary cells produce short bursts of electrical activity which are more effective than single spikes in evoking hormone release. These bursts, called pseudo-plateau bursts, are unlike bursts studied mathematically in neurons (plateau bursting) and the standard fast-slow analysis used for plateau bursting is of limited use. Using an alternative fast-slow analysis, with one fast and two slow variables, we show that pseudo-plateau bursting is a canard-induced mixed mode oscillation. Using this technique, it is possible to determine the region of parameter space where bursting occurs as well as salient properties of the burst such as the number of spikes in the burst. The information gained from this one-fast/two-slow decomposition complements the information obtained from a two-fast/one-slow decomposition. PMID:22268000

  18. Thyroid tumors following /sup 131/I or localized x irradiation to the thyroid and pituitary glands in rats

    SciTech Connect

    Lee, W.; Chiacchierini, R.P.; Shleien, B.; Telles, N.C.

    1982-11-01

    Three thousand 6-week-old female Long-Evans rats were randomly assigned to 10 equal treatment groups. Three groups were injected intraperitoneally with 0.48, 1.9, and 5.4 ..mu..Ci of Na /sup 131/I yielding mean thyroid doses of 30, 330, and 850 rad, respectively. Three groups were irradiated with 94, 410, and 1060 rad from localized X ray to the thyroid. One group was irradiated with 410 rad to the pituitary, and another group was given 410 rad to both the thyroid and the pituitary with localized X rays. The remaining two groups of animals were used as separate sham-irradiated controls for the two types of radiation. All the surviving animals were killed 2 years later. Results derived from this study indicate that: (a) The proportion of animals with thyroid carcinoma is similar for /sup 131/I and X irradiation within the dose range of 0-1000 rad. (b) The thryoid carcinoma dose-response functions fitted by the least-squares method are nearly proportional to the square root of the thyroid dose. (c) Thyroid carcinoma induction appears to be independent of the dose rates resulting from the radiations used in this study. (d) A localized X-ray dose of 410 rad to the pituitary, whether the dose was administered concomitantly with thyroid irradiation or without thyroid irradiation, did not modify the risk of thyroid tumor.

  19. Alteration of Pituitary Tumor Transforming Gene-1 Regulates Trophoblast Invasion via the Integrin/Rho-Family Signaling Pathway

    PubMed Central

    Lim, Seung Mook; Jang, Hee Yeon; Lee, Ji Eun; Shin, Joong Sik; Park, Sun-Hwa; Yoon, Bo Hyun; Kim, Gi Jin

    2016-01-01

    Trophoblast invasion ability is an important factor in early implantation and placental development. Recently, pituitary tumor transforming gene 1 (PTTG1) was shown to be involved in invasion and proliferation of cancer. However, the role of PTTG1 in trophoblast invasion remains unknown. Thus, in this study we analyzed PTTG1 expression in trophoblasts and its effect on trophoblast invasion activity and determined the mechanism through which PTTG1 regulates trophoblast invasion. Trophoblast proliferation and invasion abilities, regardless of PTTG1 expression, were analyzed by quantitative real-time polymerase chain reaction, fluorescence-activated cell sorting analysis, invasion assay, western blot, and zymography after treatment with small interfering RNA against PTTG1 (siPTTG1). Additionally, integrin/Rho-family signaling in trophoblasts by PTTG1 alteration was analyzed. Furthermore, the effect of PTTG1 on trophoblast invasion was evaluated by microRNA (miRNA) mimic and inhibitor treatment. Trophoblast invasion was significantly reduced through decreased matrix metalloproteinase (MMP)-2 and MMP-9 expression when PTTG1 expression was inhibited by siPTTG1 (p < 0.05). Furthermore, knockdown of PTTG1 increased expression of integrin alpha 4 (ITGA4), ITGA5, and integrin beta 1 (ITGB1); otherwise, RhoA expression was significantly decreased (p < 0.05). Treatment of miRNA-186-5p mimic and inhibitor controlled trophoblast invasion ability by altering PTTG1 and MMP expression. PTTG1 can control trophoblast invasion ability via regulation of MMP expression through integrin/Rho-family signaling. In addition, PTTG1 expression and its function were regulated by miRNA-186-5p. These results help in understanding the mechanism through which PTTG1 regulates trophoblast invasion and thereby implantation and placental development. PMID:26900962

  20. Melatonin modulates secretion of growth hormone and prolactin by trout pituitary glands and cells in culture.

    PubMed

    Falcón, J; Besseau, L; Fazzari, D; Attia, J; Gaildrat, P; Beauchaud, M; Boeuf, G

    2003-10-01

    In Teleost fish, development, growth, and reproduction are influenced by the daily and seasonal variations of photoperiod and temperature. Early in vivo studies indicated the pineal gland mediates the effects of these external factors, most probably through the rhythmic production of melatonin. The present investigation was aimed at determining whether melatonin acts directly on the pituitary to control GH and prolactin (PRL) secretion in rainbow trout. We show that 2-[125I]-iodomelatonin, a melatonin analog, binds selectively to membrane preparations and tissue sections from trout pituitaries. The affinity was within the range of that found for the binding to brain microsomal preparations, but the number of binding sites was 20-fold less than in the brain. In culture, melatonin inhibited pituitary cAMP accumulation induced by forskolin, the adenyl cyclase stimulator. Forskolin also induced an increase in GH release, which was reduced in the presence of picomolar concentrations of melatonin. At higher concentrations, the effects of melatonin became stimulatory. In the absence of forskolin, melatonin induced a dose-dependent increase in GH release, and a dose-dependent decrease in PRL release. Melatonin effects were abolished upon addition of luzindole, a melatonin antagonist. Our results provide the first evidence that melatonin modulates GH and PRL secretion in Teleost fish pituitary. Melatonin effects on GH have never been reported in any vertebrate before. The effects result from a direct action of melatonin on pituitary cells. The complexity of the observed responses suggests several types of melatonin receptors might be involved. PMID:12960030

  1. Electrophoretic separation of cells and particles from rat pituitary. [analysis of pituitary cell electrophoresis experiment done on IML-2 (7/94)

    NASA Technical Reports Server (NTRS)

    Hymer, W. C.

    1995-01-01

    In spite of the fact that a vast majority of the electrophoresis effort (approximately 90%) could not be done on this mission (IML-2) due to failure of FFEU hardware, we find some interesting differences in flight samples obtained from other parts of the experiment. These differences are entirely novel and sometimes unexpected. This report is organized into 4 parts. Each part describes the data collected thus far from each of the 4 cell culture kits (CCK) which flew in space. Each CCK was loaded with 40x10(exp 6) fresh pituitary cells; all CCK's were identical at the start of the experiment because we prepared one pool of cells.

  2. Inhibition of growth of a prolactin and growth hormone-secreting pituitary tumor in rats by D-tryptophan-6 analog of luteinizing hormone-releasing hormone.

    PubMed Central

    Torres-Aleman, I; Redding, T W; Schally, A V

    1985-01-01

    The effect of long-term administration of analogs of luteinizing hormone-releasing hormone (LH-RH) and somatostatin on the growth of the growth hormone (GH)- and prolactin (PRL)-secreting rat pituitary GH3 tumor was investigated. Daily administration of [D-Trp6]LH-RH (50 micrograms/day), early after inoculation of the GH3 tumor, inhibited tumor growth by more than 90% as compared to controls. Similarly, in two experiments, a single once-a-month injection of long-acting [D-Trp6]LH-RH microcapsules (in a dose calculated to release about 25 micrograms/day for 30 days) inhibited the growth of GH3 pituitary tumor by more than 50% 6 or 13 wk after transplantation, when the tumors were fully developed. Serum GH and PRL levels also were reduced markedly by treatment with [D-Trp6]LH-RH. On the other hand, the administration of an antagonistic analog of LH-RH, N-Ac-[D-Phe(4Cl)1,2, D-Trp3, D-Arg6, D-Ala10]LH-RH, did not significantly reduce the growth of this tumor, and the treatment with two different analogs of somatostatin, cyclo(Pro-Phe-D-Trp-Lys-Thr-Phe) and D-Phe-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr NH2, appeared to enhance it. These results are in agreement with previous findings of growth inhibition of 7315a pituitary tumors with different hormone-secreting characteristics by agonistic analogs of LH-RH. The collective data from experimental work with rat pituitary tumor models support the contention that the use of [D-Trp6]LH-RH might be considered for the treatment of some patients with pituitary tumors who failed to respond to conventional therapy. PMID:2858096

  3. Folliculostellate cell interacts with pericyte via TGFβ2 in rat anterior pituitary.

    PubMed

    Tsukada, Takehiro; Azuma, Morio; Horiguchi, Kotaro; Fujiwara, Ken; Kouki, Tom; Kikuchi, Motoshi; Yashiro, Takashi

    2016-05-01

    The anterior pituitary gland comprises five types of endocrine cells plus non-endocrine cells including folliculostellate cells, endothelial cells, and capillary mural cells (pericytes). In addition to being controlled by the hypothalamic-pituitary-target organ axis, the functions of these cells are likely regulated by local cell and extracellular matrix (ECM) interactions. However, these complex interactions are not fully understood. We investigated folliculostellate cell-mediated cell-to-cell interaction. Using S100β-GFP transgenic rats, which express GFP in folliculostellate cells, we designed a three-dimensional cell culture to examine the effects of folliculostellate cells. Interestingly, removal of folliculostellate cells reduced collagen synthesis (Col1a1 and Col3a1). Because pericytes are important collagen-producing cells in the gland, we stained for desmin (a pericyte marker). Removal of folliculostellate cells resulted in fewer desmin-positive pericytes and less desmin mRNA. We then attempted to identify the factor mediating folliculostellate cell-pericyte interaction. RT-PCR and in situ hybridization revealed that the important profibrotic factor transforming growth factor beta-2 (TGFβ2) was specifically expressed in folliculostellate cells and that TGFβ receptor II was expressed in pericytes, endothelial cells, and parenchymal cells. Immunocytochemistry showed that TGFβ2 induced SMAD2 nuclear translocation in pericytes. TGFβ2 increased collagen synthesis in a dose-dependent manner. This action was completely blocked by TGFβ receptor I inhibitor (SB431542). Diminished collagen synthesis in folliculostellate cell-deficient cell aggregates was partially recovered by TGFβ2. TGFβ2-mediated folliculostellate cell-pericyte interaction appears to be essential for collagen synthesis in rat anterior pituitary. This finding sheds new light on local cell-ECM interactions in the gland. PMID:26957638

  4. General Information about Pancreatic Neuroendocrine Tumors (Islet Cell Tumors)

    MedlinePlus

    ... Islet Cell Tumors) Treatment (PDQ®)–Patient Version General Information About Pancreatic Neuroendocrine Tumors (Islet Cell Tumors) Go ... the PDQ Adult Treatment Editorial Board . Clinical Trial Information A clinical trial is a study to answer ...

  5. Changes in pituitary growth hormone cells prepared from rats flown on Spacelab 3

    NASA Technical Reports Server (NTRS)

    Grindeland, R.; Hymer, W. C.; Farrington, M.; Fast, T.; Hayes, C.; Motter, K.; Patil, L.; Vasques, M.

    1987-01-01

    The effect of exposure to microgravity on pituitary gland was investigated by examining cells isolated from anterior pituitaries of rats flown on the 7-day Spacelab 3 mission and, subsequently, cultured for 6 days. Compared with ground controls, flight cells contained more intracellular growth hormone (GH); however, the flight cells released less GH over the 6-day culture period and after implantation into hypophysectomized rats than did the control cells. Compared with control rats, glands from large rats (400 g) contained more somatotrophs (44 percent compared with 37 percent in control rats); small rats (200 g) showed no difference. No major differences were found in the somatotroph ultrastructure (by TEM) or in the pattern of the immunoactive GH variants. However, high-performance liquid chromatography fractionation of culture media indicated that flight cells released much less of a biologically active high-molecular weight GH variant, suggesting that space flight may lead to secretory dysfunction.

  6. The marine metabolite SZ-685C induces apoptosis in primary human nonfunctioning pituitary adenoma cells by inhibition of the Akt pathway in vitro.

    PubMed

    Wang, Xin; Tan, Ting; Mao, Zhi-Gang; Lei, Ni; Wang, Zong-Ming; Hu, Bin; Chen, Zhi-Yong; She, Zhi-Gang; Zhu, Yong-Hong; Wang, Hai-Jun

    2015-03-01

    Nonfunctioning pituitary adenoma (NFPA) is one of the most common types of pituitary adenoma. The marine anthraquinone derivative SZ-685C has been isolated from the secondary metabolites of the mangrove endophytic fungus Halorosellinia sp. (No. 1403) which is found in the South China Sea. Recent research has shown that SZ-685C possesses anticancer and tumor suppressive effects. The tetrazolium-based colorimetric assay (MTT assay) to investigate the different effect of the marine compound SZ-685C on the proliferation of primary human NFPA cells, rat normal pituitary cells (RPCs) and rat prolactinoma MMQ cell lines. Hoechst 33342 dye/propidium iodide (PI) double staining and fluorescein isothiocyanate-conjugated Annexin V/PI (Annexin V-FITC/PI) apoptosis assays detected an enhanced rate of apoptosis in cells treated with SZ-685C. Enhanced expression levels of caspase 3 and phosphate and tensin homolog (PTEN) were determined by Western blotting. Notably, the protein expression levels of Akt were decreased when the primary human NFPA cells were treated with SZ-685C. Here, we show that SZ-685C induces apoptosis of human NFPA cells through inhibition of the Akt pathway in vitro. The understanding of apoptosis has provided the basis for novel targeted therapies that can induce death in cancer cells or sensitize them to established cytotoxic agents and radiation therapy. PMID:25806467

  7. Premature differentiation and aberrant movement of pituitary cells lacking both Hes1 and Prop1

    PubMed Central

    Himes, Ashley D.; Raetzman, Lori T.

    2009-01-01

    In the pituitary, the transition from proliferating progenitor cell into differentiated hormone producing cell is carefully regulated in a time dependent and spatially restricted manner. We report that two targets of Notch signaling, Hes1 and Prop1, are needed to maintain progenitors within Rathke’s pouch and for the restriction of differentiated cells to the ventral pituitary. We observed ACTH and αGSU producing cells that had prematurely differentiated within Rathke’s pouch along with correlated ectopic expression of Mash1 only when both Prop1 and Hes1 were lost. We also discovered that downregulation of N-cadherin expression in cells as they transition from Rathke’s pouch to the anterior lobe appears to be essential for their movement. In the Prop1 mutant, cells are trapped in Rathke’s pouch and N-cadherin expression remains high. Also, Slug, a marker of epithelial to mesenchymal transition, is absent in the dorsal anterior lobe. When Hes1 is lost in the Prop1 mutant, N-cadherin is downregulated and cells are able to exit Rathke’s pouch but have lost their migrational cues and form ectopic foci surrounding Rathke’s pouch. Our data reveal important overlapping functions of Hes1 and Prop1 in cell differentiation and movement that are critical for pituitary organogenesis. PMID:18996108

  8. Morphometric analysis of the human anterior pituitary's folliculostellate cells during the aging process.

    PubMed

    Pavlović, Miljana; Jovanović, Ivan; Ugrenović, Slađana; Vasović, Ljiljana; Krstić, Miljan; Bakić, Mirjana; Živković, Vladimir; Stojanović, Vesna

    2013-05-01

    Folliculostellate cells represent non-endocrine cells of the anterior pituitary which influence the function of the endocrine cells via paracrine action. Though there is a lack of literature data on their presence during human aging, the aim of this research was to perform the quantification of anterior pituitary folliculostellate cells by the application of immunohistochemical and morphometric methods. The material for the study consisted of 15 anterior pituitaries taken from cadavers at routine autopsy. Their tissue was processed by standard histological procedure and the obtained histological slices were stained by S100 polyclonal antibody. Digital images of stained histological sections were analyzed by morphometric method with ImageJ system. The volume density of S100 positive cells was measured for each case. Results of morphometric and statistical analysis showed a significantly positive correlation between folliculostellate cell volume density and the age of the evaluated cases. Linear regression additionally showed that the age significantly predicts folliculostellate cells volume density in our sample. Further, all cases were classified into three age groups and One Way ANOVA showed that the volume density of folliculostellate cells was significantly higher only in the third age group in relation to the first and the second group, respectively. Volume densities of the first and the second age groups were not significantly different. So, the results of our study pointed to the conclusion that folliculostellate cells presence generally increases with age, but this increase is significant only in the oldest cases and might represent the modality of successful anterior pituitary aging. PMID:23295121

  9. Serum-free growth of human mammary epithelial cells: rapid clonal growth in defined medium and extended serial passage with pituitary extract

    SciTech Connect

    Hammond, S.L.; Ham, R.G.; Stampfer, M.R.

    1984-09-01

    A serum-free medium with bovine pituitary extract as the only undefined supplement has been developed for long-term culture of human mammary epithelial cells. This medium supports serial subculture of normal cells for 10-20 passages (1:10 splits) without conditioning or special substrates, and it supports rapid clonal growth with plating efficiencies up to 35%. It consists of an optimized basal nutrient medium, (MCDB 170, supplemented with insulin, hydrocortisone, epidermal growth factor, ethanolamine, phosphoethanolamine, and bovine pituitary extract. Replacement of pituitary extract with prostaglandin E/sub 1/ and ovine prolactin yields a defined medium that supports rapid clonal growth and serial subculture for three of four passages. Cultures initiated in these media from normal reduction mammoplasty tissue remain diploid and maintain normal epithelia morphology, distribution of cell-associated fibronectin, expression of keratin fibrils, and a low level of expression of milk fat globule antigen. Large cell populations can now be generated and stored frozen, permitting multiple experiments over a period of time with cells from a single donor. These media greatly extend the range of experiments that can be performed both conveniently and reproducibly with cultured normal and tumor-derived human mammary epithelial cells. 31 references, 3 figures, 4 tables.

  10. Detection of Circulating Tumor Cells

    PubMed Central

    Terstappen, Leon W. M. M.

    2014-01-01

    The increasing number of treatment options for patients with metastatic carcinomas has created an accompanying need for methods to determine if the tumor will be responsive to the intended therapy and to monitor its effectiveness. Ideally, these methods would be noninvasive and provide quantitative real-time analysis of tumor activity in a variety of carcinomas. Assessment of circulating tumor cells shed into the blood during metastasis may satisfy this need. Here we review the CellSearch technology used for the detection of circulating tumor cells and discuss potential future directions for improvements. PMID:25133014

  11. PROP1 triggers epithelial-mesenchymal transition-like process in pituitary stem cells

    PubMed Central

    Pérez Millán, María Inés; Brinkmeier, Michelle L; Mortensen, Amanda H; Camper, Sally A

    2016-01-01

    Mutations in PROP1 are the most common cause of hypopituitarism in humans; therefore, unraveling its mechanism of action is highly relevant from a therapeutic perspective. Our current understanding of the role of PROP1 in the pituitary gland is limited to the repression and activation of the pituitary transcription factor genes Hesx1 and Pou1f1, respectively. To elucidate the comprehensive PROP1-dependent gene regulatory network, we conducted genome-wide analysis of PROP1 DNA binding and effects on gene expression in mutant mice, mouse isolated stem cells and engineered mouse cell lines. We determined that PROP1 is essential for stimulating stem cells to undergo an epithelial to mesenchymal transition-like process necessary for cell migration and differentiation. Genomic profiling reveals that PROP1 binds to genes expressed in epithelial cells like Claudin 23, and to EMT inducer genes like Zeb2, Notch2 and Gli2. Zeb2 activation appears to be a key step in the EMT process. Our findings identify PROP1 as a central transcriptional component of pituitary stem cell differentiation. DOI: http://dx.doi.org/10.7554/eLife.14470.001 PMID:27351100

  12. Experimental Modification of Rat Pituitary Growth Hormone Cell Function During and After Spaceflight

    NASA Technical Reports Server (NTRS)

    Hymer, W. C.; Salada, T.; Nye, P.; Grossman, E. J.; Lane, P. K.; Grindeland, R. E.

    1996-01-01

    Space-flown rats show a number of flight-induced changes in the structure and function of pituitary Growth Hormone (GH) cells after in vitro postflight testing. To evaluate the possible effects of microgravity on GH cells themselves, freshly dispersed rat anterior pituitary gland cells were seeded into vials containing serum +/- 1 micron HydroCortisone (HC) before flight. Five different cell preparations were used: the entire mixed-cell population of various hormone-producing cell types, cells of density less than 1.071 g/sq cm (band 1), cells of density greater than 1.071 g/sq cm (band 2), and cells prepared from either the dorsal or ventral part of the gland. Relative to ground control samples, bioactive GH released from dense cells during flight was reduced in HC-free medium but was increased in HC-containing medium. Band I and mixed cells usually showed opposite HC-dependent responses. Release of bioactive GH from ventral flight cells was lower; postflight responses to GH-releasing hormone challenge were reduced, and the cytoplasmic area occupied by GH in the dense cells was greater. Collectively, the data show that the chemistry and cellular makeup of the culture system modifies the response of GH cells to microgravity. As such, these cells offer a system to identify gravisensing mechanisms in secretory cells in future microgravity research.

  13. Deformability of Tumor Cells versus Blood Cells.

    PubMed

    Shaw Bagnall, Josephine; Byun, Sangwon; Begum, Shahinoor; Miyamoto, David T; Hecht, Vivian C; Maheswaran, Shyamala; Stott, Shannon L; Toner, Mehmet; Hynes, Richard O; Manalis, Scott R

    2015-01-01

    The potential for circulating tumor cells (CTCs) to elucidate the process of cancer metastasis and inform clinical decision-making has made their isolation of great importance. However, CTCs are rare in the blood, and universal properties with which to identify them remain elusive. As technological advancements have made single-cell deformability measurements increasingly routine, the assessment of physical distinctions between tumor cells and blood cells may provide insight into the feasibility of deformability-based methods for identifying CTCs in patient blood. To this end, we present an initial study assessing deformability differences between tumor cells and blood cells, indicated by the length of time required for them to pass through a microfluidic constriction. Here, we demonstrate that deformability changes in tumor cells that have undergone phenotypic shifts are small compared to differences between tumor cell lines and blood cells. Additionally, in a syngeneic mouse tumor model, cells that are able to exit a tumor and enter circulation are not required to be more deformable than the cells that were first injected into the mouse. However, a limited study of metastatic prostate cancer patients provides evidence that some CTCs may be more mechanically similar to blood cells than to typical tumor cell lines. PMID:26679988

  14. Deformability of Tumor Cells versus Blood Cells

    PubMed Central

    Shaw Bagnall, Josephine; Byun, Sangwon; Begum, Shahinoor; Miyamoto, David T.; Hecht, Vivian C.; Maheswaran, Shyamala; Stott, Shannon L.; Toner, Mehmet; Hynes, Richard O.; Manalis, Scott R.

    2015-01-01

    The potential for circulating tumor cells (CTCs) to elucidate the process of cancer metastasis and inform clinical decision-making has made their isolation of great importance. However, CTCs are rare in the blood, and universal properties with which to identify them remain elusive. As technological advancements have made single-cell deformability measurements increasingly routine, the assessment of physical distinctions between tumor cells and blood cells may provide insight into the feasibility of deformability-based methods for identifying CTCs in patient blood. To this end, we present an initial study assessing deformability differences between tumor cells and blood cells, indicated by the length of time required for them to pass through a microfluidic constriction. Here, we demonstrate that deformability changes in tumor cells that have undergone phenotypic shifts are small compared to differences between tumor cell lines and blood cells. Additionally, in a syngeneic mouse tumor model, cells that are able to exit a tumor and enter circulation are not required to be more deformable than the cells that were first injected into the mouse. However, a limited study of metastatic prostate cancer patients provides evidence that some CTCs may be more mechanically similar to blood cells than to typical tumor cell lines. PMID:26679988

  15. Differential DNA methylome profiling of nonfunctioning pituitary adenomas suggesting tumour invasion is correlated with cell adhesion.

    PubMed

    Gu, Ye; Zhou, Xinyao; Hu, Fan; Yu, Yong; Xie, Tao; Huang, Yuying; Zhao, Xinzhi; Zhang, Xiaobiao

    2016-08-01

    Global and gene-specific changes to the epigenome are hallmarks of most tumours including those of pituitary origin, and this fact might offer important clues about diagnostic and therapeutic applications. We performed global DNA methylation screening with 6 invasive and 6 noninvasive nonfunctioning pituitary adenomas (PA) to investigate whether DNA methylation was associated with the invasion of nonfunctioning pituitary adenomas. An additional seven PAs were included as an independent cohort to validate the initial results. Five thousand nine hundred thirty-one CpGs were selected (△β ≥0.15 and p value ≤0.01) as differentially methylated sites (DMSs). The hypomethylated DMSs in the invasive PAs were significantly more than the hypermethylated sites. Cluster analysis of 339 CpGs (△β ≥0.25 and p value ≤0.001) demonstrated a complete distinction between the invasive and noninvasive nonfunctioning groups. GO analysis of the three hundred seven corresponding genes shown they were involved in homophilic cell adhesion, cell-cell adhesion, cell adhesion and biological adhesion. The mRNA expression of GALNT9 which contain a validated DMS was significantly downregulated in invasive group. Our findings indicate that the differential DNA methylome profiling of invasive and noninvasive nonfunctioning PAs suggesting tumour invasion is correlated with cell adhesion. PMID:27168190

  16. Exogenous action of 5-lipoxygenase by its metabolites on luteinizing hormone release in rat pituitary cells.

    PubMed

    Przylipiak, A; Kiesel, L; Habenicht, A J; Przylipiak, M; Runnebaum, B

    1990-02-12

    The stimulatory effect of exogenously administered potato 5-lipoxygenase (0.1-0.3 U/2 ml) on luteinizing hormone (LH) release was demonstrated in rat anterior pituitary cells in a superfusion system. Nordihydroguaiaretic acid (NDGA), an inhibitor of 5-lipoxygenase, abolished the effect of the enzyme on LH secretion. The secretory effect on LH after 5-lipoxygenase administration was biphasic and dependent on Ca2+ indicating that 5-lipoxygenase affects LH release through its oxygenation reaction. Another series of experiments demonstrated that activation of 5-lipoxygenase, expressed as production of leukotriene (LT) B4 and C4 (728 +/- 127 pg/10(6) cells and 178 +/- 23 pg/10(6) cells, respectively) occurs in rat pituitary cells after addition of Ca2+ ionophore A23187. However, LTB4 and LTC4 were not formed by pituitary cells that had previously been desensitized by gonadotropin-releasing hormone (GnRH), the physiological ligand of LH release. These results are consistent with a role of 5-lipoxygenase metabolites in the mechanism of GnRH-induced LH secretion. PMID:2157615

  17. Cyclosporine A induces apoptotic and autophagic cell death in rat pituitary GH3 cells.

    PubMed

    Kim, Han Sung; Choi, Seung-Il; Jeung, Eui-Bae; Yoo, Yeong-Min

    2014-01-01

    Cyclosporine A (CsA) is a powerful immunosuppressive drug with side effects including the development of chronic nephrotoxicity. In this study, we investigated CsA treatment induced apoptotic and autophagic cell death in pituitary GH3 cells. CsA treatment (0.1 to 10 µM) decreased survival of GH3 cells in a dose-dependent manner. Cell viability decreased significantly with increasing CsA concentrations largely due to an increase in apoptosis, while cell death rates due to autophagy altered only slightly. Several molecular and morphological features correlated with cell death through these distinct pathways. At concentrations ranging from 1.0 to 10 µM, CsA induced a dose-dependent increase in expression of the autophagy markers LC3-I and LC3-II. Immunofluorescence staining revealed markedly increased levels of both LC3 and lysosomal-associated membrane protein 2 (Lamp2), indicating increases in autophagosomes. At the same CsA doses, apoptotic cell death was apparent as indicated by nuclear and DNA fragmentation and increased p53 expression. In apoptotic or autophagic cells, p-ERK levels were highest at 1.0 µM CsA compared to control or other doses. In contrast, Bax levels in both types of cell death were increased in a dose-dependent manner, while Bcl-2 levels showed dose-dependent augmentation in autophagy and were decreased in apoptosis. Manganese superoxide dismutase (Mn-SOD) showed a similar dose-dependent reduction in cells undergoing apoptosis, while levels of the intracellular calcium ion exchange maker calbindin-D9k were decreased in apoptosis (1.0 to 5 µM CsA), but unchanged in autophagy. In conclusion, these results suggest that CsA induction of apoptotic or autophagic cell death in rat pituitary GH3 cells depends on the relative expression of factors and correlates with Bcl-2 and Mn-SOD levels. PMID:25299210

  18. Angiogenesis in Pituitary Adenomas: Human Studies and New Mutant Mouse Models

    PubMed Central

    Cristina, Carolina; Demarchi, Gianina; Lopez Vicchi, Felicitas; Perez Millan, Maria Ines; Perrone, Sofia; Ornstein, Ana Maria; Berner, Silvia Inés; Becu-Villalobos, Damasia

    2014-01-01

    The role of angiogenesis in pituitary tumor development has been questioned, as pituitary tumors have been usually found to be less vascularized than the normal pituitary tissue. Nevertheless, a significantly higher degree of vasculature has been shown in invasive or macropituitary prolactinomas when compared to noninvasive and microprolactinomas. Many growth factors and their receptors are involved in pituitary tumor development. For example, VEGF, FGF-2, FGFR1, and PTTG, which give a particular vascular phenotype, are modified in human and experimental pituitary adenomas of different histotypes. In particular, vascular endothelial growth factor, VEGF, the central mediator of angiogenesis in endocrine glands, was encountered in experimental and human pituitary tumors at different levels of expression and, in particular, was higher in dopamine agonist resistant prolactinomas. Furthermore, several anti-VEGF techniques lowered tumor burden in human and experimental pituitary adenomas. Therefore, even though the role of angiogenesis in pituitary adenomas is contentious, VEGF, making permeable pituitary endothelia, might contribute to adequate temporal vascular supply and mechanisms other than endothelial cell proliferation. The study of angiogenic factor expression in aggressive prolactinomas with resistance to dopamine agonists will yield important data in the search of therapeutical alternatives. PMID:25505910

  19. Overexpression of the growth-hormone-releasing hormone gene in acromegaly-associated pituitary tumors. An event associated with neoplastic progression and aggressive behavior.

    PubMed Central

    Thapar, K.; Kovacs, K.; Stefaneanu, L.; Scheithauer, B.; Killinger, D. W.; Lioyd, R. V.; Smyth, H. S.; Barr, A.; Thorner, M. O.; Gaylinn, B.; Laws, E. R.

    1997-01-01

    The clinical behavior of growth hormone (GH)-producing pituitary tumors is known to vary greatly; however, the events underlying this variability remain poorly understood. Herein we demonstrate that tumor overexpression of the GH-releasing hormone (GHRH) gene is one prognostically informative event associated with the clinical aggressiveness of somatotroph pituitary tumors. Accumulation of GHRH mRNA transcripts was demonstrated in 91 of a consecutive series of 100 somatotroph tumors by in situ hybridization; these findings were corroborated by Northern analysis and reverse transcriptase polymerase chain reaction, and protein translation was confirmed by Western blotting. By comparison, transcript accumulation was absent or negligibly low in 30 normal pituitary glands. GHRH transcripts were found to preferentially accumulate among clinically aggressive tumors. Specifically, GHRH mRNA signal intensity was 1) linearly correlated with Ki-67 tumor growth fractions (r = 0.71; P < 0.001), 2) linearly correlated with preoperative serum GH levels (r = 0.56; p = 0.01), 3) higher among invasive tumors (P < 0.001), and 4) highest in those tumors in which post-operative remission was not achieved (P < 0.001). Using multivariate logistic regression, a model of postoperative remission likelihood was derived wherein remission was defined by the single criterion of suppressibility of GH levels to less than 2 ng/ml during an oral glucose tolerance test. In this outcome model, GHRH mRNA signal intensity proved to be the most important explanatory variable overall, eclipsing any and all conventional clinicopathological predictors as the single most significant predictor of postoperative remission; increases in GHRH mRNA signal were associated with marked declines in remission likelihood. The generalizability of this outcome model was further validated by the model's significant performance in predicting postoperative remission in a random sample of 30 somatotroph tumors treated at

  20. A geometric understanding of how fast activating potassium channels promote bursting in pituitary cells.

    PubMed

    Vo, Theodore; Tabak, Joël; Bertram, Richard; Wechselberger, Martin

    2014-04-01

    The electrical activity of endocrine pituitary cells is mediated by a plethora of ionic currents and establishing the role of a single channel type is difficult. Experimental observations have shown however that fast-activating voltage- and calcium-dependent potassium (BK) current tends to promote bursting in pituitary cells. This burst promoting effect requires fast activation of the BK current, otherwise it is inhibitory to bursting. In this work, we analyze a pituitary cell model in order to answer the question of why the BK activation must be fast to promote bursting. We also examine how the interplay between the activation rate and conductance of the BK current shapes the bursting activity. We use the multiple timescale structure of the model to our advantage and employ geometric singular perturbation theory to demonstrate the origin of the bursting behaviour. In particular, we show that the bursting can arise from either canard dynamics or slow passage through a dynamic Hopf bifurcation. We then compare our theoretical predictions with experimental data using the dynamic clamp technique and find that the data is consistent with a burst mechanism due to a slow passage through a Hopf. PMID:23820858

  1. [Primary Pituitary Malignant Lymphoma that was Difficult to Differentiate from Nonfunctioning Pituitary Adenoma:A Case Report].

    PubMed

    Murakami, Yuta; Sato, Taku; Jinguji, Shinya; Kishida, Yugo; Watanabe, Tadashi; Suzuki, Osamu; Ikeda, Kazuhiko; Homma, Miyuki; Midorikawa, Sanae; Saito, Kiyoshi

    2016-09-01

    We report a rare case of primary pituitary lymphoma in a 75-year-old immunocompetent woman. The patient was blind in the right eye and presented with visual disturbance in the left eye that started 2 months previously. She also exhibited right third and fifth cranial nerve palsy. Magnetic resonance imaging(MRI)revealed an intrasellar mass lesion with right cavernous sinus invasion and suprasellar extension with compression of the optic chiasm. The mass lesion was isointense on both T1WI and T2WI, and showed less enhancement than a normal pituitary gland on gadolinium-enhanced T1WI. We therefore suspected the tumor to be a nonfunctioning pituitary adenoma. The patient underwent endoscopic endonasal transsphenoidal surgery. The tumor was firm and grayish, and had an ill-defined border along the normal pituitary gland. Histological examination revealed a malignant CD5-positive diffuse large B-cell lymphoma. After surgery, the patient received both chemotherapy and radiotherapy. Although the visual acuity of the right eye did not improved, other symptoms improved. At the 34-month follow-up, no recurrence was detected on serial MRI. Patients with primary pituitary lymphoma often exhibit ophthalmoplegia and/or panhypopituitarism more frequently than expected from radiological findings. In cases of pituitary tumors with atypical symptoms, a biopsy and general physical examination should be performed immediately to determine the diagnosis and perform adjuvant therapy even when the tumor is assumed as nonfunctioning pituitary adenoma from the image findings. PMID:27605481

  2. Effects of Prenatal Dexamethasone on the Rat Pituitary Gland and Gonadotropic Cells in Female Offspring.

    PubMed

    Ristić, Nataša; Severs, Walter; Nestorović, Nataša; Jarić, Ivana; Manojlović-Stojanoski, Milica; Trifunović, Svetlana; Pendovski, Lazo; Milosević, Verica

    2016-01-01

    Glucocorticoids have a strong influence on growth and maturation of fetal organ systems, but overexposure to exogenous glucocorticoids may retard fetal growth and alter developmental processes in sensitive tissues. The aim of this study was to specifically determine whether prenatal exposure to dexamethasone (Dx) altered normal development and function of pituitary gonadotropic cells in neonatal, infant and peripubertal female offspring. On day 16 of pregnancy, rat dams received 1.0 mg Dx/kg body weight (BW) s.c., followed by 0.5 mg Dx/kg BW on days 17 and 18 of gestation. Control gravid females received the same volume of saline. Female offspring were sacrificed on days 5, 16 and 38 after delivery. The volume of the pituitary gland estimated using Cavalieri's principle was significantly reduced (p < 0.05). Using a fractionator-physical disector method, we found reduced total numbers of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) cells (p < 0.05), accompanied by a decrease (p < 0.05) in serum concentrations of FSH and LH, while the relative intensity of FSH and LH immunofluorescence remained unchanged in neonatal, infant and peripubertal female offspring prenatally exposed to Dx. The data document that overexposure to Dx during fetal development evokes developmental programming of the female reproductive system at the pituitary cellular level, which may be associated with impaired reproductive function. PMID:26950885

  3. In vivo and in vitro effects of chromium VI on anterior pituitary hormone release and cell viability

    SciTech Connect

    Quinteros, Fernanda A.; Poliandri, Ariel H.B.; Machiavelli, Leticia I.; Cabilla, Jimena P.; Duvilanski, Beatriz H. . E-mail: neuroend@ffyb.uba.ar

    2007-01-01

    Hexavalent chromium (Cr VI) is a highly toxic metal and an environmental pollutant. Different studies indicate that Cr VI exposure adversely affects reproductive functions. This metal has been shown to affect several tissues and organs but Cr VI effects on pituitary gland have not been reported. Anterior pituitary hormones are central for the body homeostasis and have a fundamental role in reproductive physiology. The aim of this study was to evaluate the effect of Cr VI at the pituitary level both in vivo and in vitro. We showed that Cr VI accumulates in the pituitary and hypothalamus, and decreases serum prolactin levels in vivo but observed no effects on LH levels. In anterior pituitary cells in culture, the effect of Cr VI on hormone secretion followed the same differential pattern. Besides, lactotrophs were more sensitive to the toxicity of the metal. As a result of oxidative stress generation, Cr VI induced apoptosis evidenced by nuclear fragmentation and caspase 3 activation. Our results indicate that the anterior pituitary gland can be a target of Cr VI toxicity in vivo and in vitro, thus producing a negative impact on the hypothalamic-pituitary-gonadal axis and affecting the normal endocrine function.

  4. Tumor angiogenesis--characteristics of tumor endothelial cells.

    PubMed

    Hida, Kyoko; Maishi, Nako; Torii, Chisaho; Hida, Yasuhiro

    2016-04-01

    Tumor blood vessels provide nutrition and oxygen to the tumor, resulting in tumor progression. They also act as gatekeepers, inducing tumor metastasis. Thus, targeting tumor blood vessels is an important strategy in cancer therapy. Tumor endothelial cells (TECs), which line the inner layer of blood vessels of the tumor stromal tissue, are the main targets of anti-angiogenic therapy. Because new tumor blood vessels generally sprout from pre-existing vasculature, they have been considered to be the same as normal blood vessels. However, tumor blood vessels demonstrate a markedly abnormal phenotype that includes several important morphological changes. The degree of angiogenesis is determined by the balance between the angiogenic stimulators and inhibitors released by the tumor and host cells. Recent studies have revealed that TECs also exhibit altered characteristics which depend on the tumor microenvironment. Here, we review recent studies on TEC abnormalities and heterogeneity with respect to tumor progression and consider their therapeutic implications. PMID:26879652

  5. [Ovarian germ cell tumors in girls].

    PubMed

    Nechushkina, I V; Karseladze, A I

    2015-01-01

    Morphological structure of tumor influences on the clinical course of the disease in children with germ cell tumors. Patients with ovarian dysgerminoma at the time of diagnosis are significantly older than patients with immature teratoma and yolk sac tumor. Immature teratoma and mixed germ cell tumors are significantly larger compared to other germ cell tumors. Yolk sac tumor and embryonal carcinoma are the most common cause of emergency surgical interventions and are accompanied by rupture of tumor capsule. PMID:26087605

  6. Dopamine inhibits somatolactin gene expression in tilapia pituitary cells through the dopamine D2 receptors.

    PubMed

    Jiang, Quan; Lian, Anji; He, Qi

    2016-07-01

    Dopamine (DA) is an important neurotransmitter in the central nervous system of vertebrates and possesses key hypophysiotropic functions. Early studies have shown that DA has a potent inhibitory effect on somatolactin (SL) release in fish. However, the mechanisms responsible for DA inhibition of SL gene expression are largely unknown. To this end, tilapia DA type-1 (D1) and type-2 (D2) receptor transcripts were examined in the neurointermediate lobe (NIL) of the tilapia pituitary by real-time PCR. In tilapia, DA not only was effective in inhibiting SL mRNA levels in vivo and in vitro, but also could abolish pituitary adenylate cyclase-activating polypeptide (PACAP)- and salmon gonadotropin-releasing hormone (sGnRH)-stimulated SL gene expression at the pituitary level. In parallel studies, the specific D2 receptor agonists quinpirole and bromocriptine could mimic the DA-inhibited SL gene expression. Furthermore, the D2 receptor antagonists domperidone and (-)-sulpiride could abolish the SL response to DA or the D2 agonist quinpirole, whereas D1 receptor antagonists SCH23390 and SKF83566 were not effective in this respect. In primary cultures of tilapia NIL cells, D2 agonist quinpirole-inhibited cAMP production could be blocked by co-treatment with the D2 antagonist domperidone and the ability of forskolin to increase cAMP production was also inhibited by quinpirole. Using a pharmacological approach, the AC/cAMP pathway was shown to be involved in quinpirole-inhibited SL mRNA expression. These results provide evidence that DA can directly inhibit SL gene expression at the tilapia pituitary level via D2 receptor through the AC/cAMP-dependent mechanism. PMID:26970582

  7. Receptors for corticotropin-releasing hormone in human pituitary: Binding characteristics and autoradiographic localization to immunocytochemically defined proopiomelanocortin cells

    SciTech Connect

    Smets, G.; Vauquelin, G.; Moons, L.; Smitz, J.; Kloeppel, G. )

    1991-08-01

    Using autoradiography combined with immunocytochemistry, the authors demonstrated that the target cells of CRH in the human pituitary were proopiomelanocortin cells. Scatchard analysis of (125I)Tyr0-oCRH saturation binding revealed the presence of one class of saturable, high affinity sites on pituitary tissue homogenate. The equilibrium dissociation constant (Kd) for (125I)Tyr0-oCRH ranged from 1.1-1.6 nM, and the receptor density was between 200-350 fmol/mg protein. Fixation of cryostat sections with 4% paraformaldehyde before tracer incubation improved both tissue preservation and localization of the CRH receptor at the cellular level. Additional postfixation with 1% glutaraldehyde inhibited tracer diffusion during subsequent immunocytochemistry and autoradiography. (125I)Tyr0-oCRH was found in cytoplasmic inclusions or at the cell periphery of ACTH/beta-endorphin cells in the anterior pituitary. Single cells of the posterior pituitary were also CRH receptor positive. Cells staining for PRL or GH were CRH receptor negative. They conclude that CRH binds only to high affinity receptors on ACTH/{beta}-endorphin cells in the human pituitary.

  8. [Practice guideline for diagnosis and treatment of craniopharyngioma and parasellar tumors of the pituitary gland].

    PubMed

    Venegas, Eva; Concepcion, Blanco; Martin, Tomas; Soto, Alfonso

    2015-01-01

    Craniopharyngiomas are rare, locally aggressive epithelial tumors usually located in the sellar and suprasellar region. Diagnosis of craniopharyngioma is usually suggested by clinical and radiological findings that should be confirmed histologically. Surgery is the treatment of choice for most patients. The goal of surgery is to relieve compressive symptoms and to remove as much tumor as safely possible. Radiation therapy is the usual treatment to control postoperative tumor remnants and local recurrences. Parasellar lesions are low prevalent lesions and include neoplastic, inflammatory, infectious, developmental, and vascular diseases. Both their diagnosis and treatment depend on the type of lesion. PMID:25066506

  9. Experimental Modification of Rat Pituitary Prolactin Cell Function During and After Spaceflight

    NASA Technical Reports Server (NTRS)

    Hymer, W. C.; Salada, T.; Avery, L.; Grindeland, R. E.

    1996-01-01

    Experimental modification of rat pituitary prolactin cell function during and after spaceflight. This study was done to evaluate the effects of microgravity on prolactin (PRL) cells of the male rat pituitary gland. We used the identical passive closed-vial cell culture system that was described for the culture of growth hormone cells (W C. Hymer, R. E. Grindeland, T. Salada, P. Nye, E. Grossman, and R Lane). After an 8-day spaceflight, all flight media (containing released PRL), as well as extracts (containing intracellular PRL), contained significantly lower amounts of immunoreactive PRL than their corresponding ground control samples. On the other hand, these same samples, when assessed for their biological activities by two different in vitro lymphocyte assays, yielded disparate results that may reflect posttranslational modifications to the hormone molecule. Other data showed that: (1) the apparent molecular weights of released PRL molecules were not altered by microgravity; but (2) the region from which the PRL cells came (dorsal or ventral) made a significant difference in the amount and activity of PRL released from the flight cells. Because there is much current interest in the role that PRL may play in the regulation of the immune system and because changes in both cellular and humoral immunity accompany spaceflight, this study could help define future microgravity research in this area.

  10. Effects of spaceflight on rat pituitary cell function

    NASA Technical Reports Server (NTRS)

    Hymer, W. C.; Grindeland, R.; Krasnov, I.; Viktorov, I.; Motter, K.; Mukherjee, P.; Shellenberger, K.; Vasques, M.

    1992-01-01

    The secretory capacity of growth hormone (GH) and prolactin (PRL) cells prepared from rats flown in space on the 12.5 day mission of Cosmos 1887 and the 14 day mission of Cosmos 2044 was evaluated in several post-flight tests on earth. The results showed statistically significant and repeatable decrements in hormone release, especially when biological assays (rather than immunological assays) were used in the tests. Significant and repeatable intracellular changes in GH cells from the flight animals were also found; most important were increases in the GH-specific cytoplasmic staining intensities and cytoplasmic areas occupied by hormone. Tail suspension of rats for 14 days, an established model for mimicking musculo-skeletal changes seen in spaceflown rats, results in some changes in GH and PRL cell function that were similar to those from spaceflown animals. Our results add to a growing body of data that described deconditioning of physiological systems in spaceflight and provide insights into the time frame that might be required for readaptation of the GH/PRL cell system upon return to earth.

  11. Molecular mechanisms of regulation of growth hormone gene expression in cultured rat pituitary cells by thyroid and glucocorticoid hormones

    SciTech Connect

    Yaffe, B.M.

    1989-01-01

    In cultured GC cells, a rat pituitary tumor cell line, growth hormone (GH) is induced in a synergistic fashion by physiologic concentrations of thyroid and glucocorticoid hormones. Abundant evidence indicates that these hormones mediate this response via their specific receptors. The purpose of this thesis is to explore the mechanisms by which these hormones affect GH production. When poly (A){sup +} RNA was isolated from cells grown both with and without hormones and translated in a cell-free wheat germ system, the preGH translation products were shown to be proportional to immunoassayable GH production under all combinations of hormonal milieux, indicating that changes in GH production is modulated at a pretranslational level. A cDNA library was constructed from poly (A){sup +}RNA and one clone containing GH cDNA sequences was isolated. This was used to confirm the above results by Northern dot blot analysis. This probe was also used to assess hormonal effects on GH mRNA half-life and synthetic rates as well as GH gene transcription rates in isolated nuclei. Using a pulse-chase protocol in which cellular RNA was labeled in vivo with ({sup 3}H)uridine, and quantitating ({sup 3}H)GHmRNA directly by hybridization to GH cDNA bound to nitrocellulose filters, GHmRNA was found to have a half-life of approximately 50 hours, and was not significantly altered by the presence of inducing hormones.

  12. Methylmercury inhibits prolactin release in a cell line of pituitary origin

    PubMed Central

    Maués, L.A.L.; Macchi, B.M.; Crespo-López, M.E.; Nasciutti, L.E.; Picanço-Diniz, D.L.W.; Antunes-Rodrigues, J.; do Nascimento, J.L.M.

    2015-01-01

    Heavy metals, such as methylmercury, are key environmental pollutants that easily reach human beings by bioaccumulation through the food chain. Several reports have demonstrated that endocrine organs, and especially the pituitary gland, are potential targets for mercury accumulation; however, the effects on the regulation of hormonal release are unclear. It has been suggested that serum prolactin could represent a biomarker of heavy metal exposure. The aim of this study was to evaluate the effect of methylmercury on prolactin release and the role of the nitrergic system using prolactin secretory cells (the mammosomatotroph cell line, GH3B6). Exposure to methylmercury (0-100 μM) was cytotoxic in a time- and concentration-dependent manner, with an LC50 higher than described for cells of neuronal origin, suggesting GH3B6 cells have a relative resistance. Methylmercury (at exposures as low as 1 μM for 2 h) also decreased prolactin release. Interestingly, inhibition of nitric oxide synthase by N-nitro-L-arginine completely prevented the decrease in prolactin release without acute neurotoxic effects of methylmercury. These data indicate that the decrease in prolactin production occurs via activation of the nitrergic system and is an early effect of methylmercury in cells of pituitary origin. PMID:26108095

  13. Pineal Diffuse Large B-Cell Lymphoma Concomitant With Pituitary Prolactinoma: Possible Correlation Between 2 Distinguished Pathologies

    PubMed Central

    Kim, Yeong-Jin; Kim, Hee Kyung; Yang, Deok-Hwan; Jung, Shin; Noh, Myung-Giun; Lee, Jae-Hyuk; Lee, Kyung-Hwa; Moon, Kyung-Sub

    2016-01-01

    Abstract This is the first reported case of pineal lymphoma with concomitant prolactin-producing pituitary adenoma. A 51-year-old male experienced worsening headaches accompanied by nausea, diplopia, and memory loss for 1 month. Cranial nerve examination revealed bilateral upward gaze limitation with convergence impairment, which is known as Parinaud syndrome. Magnetic resonance images revealed a mass in the pineal gland with a coexisting mass within the enlarged sella fossa. Hormone analysis revealed hyperprolactinemia. The pineal mass was removed without injuring the hypothalamus, brain stem, or any neighboring vessels. Pathology examination confirmed the diagnosis of diffuse large B-cell lymphoma (DLBCL) involving the pineal gland. After further studies, the pineal lymphoma was determined to be a secondary tumor from a gastric primary tumor. The patient died 6 months after diagnosis due to systemic progression of DLBCL. Although the mechanistic link between hyperprolactinemia and lymphoma progression has not been clarified on a clinical basis, high prolactin levels may contribute to the rapid progression and therapeutic resistance of the lymphoma. PMID:26937937

  14. Pineal Diffuse Large B-Cell Lymphoma Concomitant With Pituitary Prolactinoma: Possible Correlation Between 2 Distinguished Pathologies: A Case Report.

    PubMed

    Kim, Yeong-Jin; Kim, Hee Kyung; Yang, Deok-Hwan; Jung, Shin; Noh, Myung-Giun; Lee, Jae-Hyuk; Lee, Kyung-Hwa; Moon, Kyung-Sub

    2016-02-01

    This is the first reported case of pineal lymphoma with concomitant prolactin-producing pituitary adenoma.A 51-year-old male experienced worsening headaches accompanied by nausea, diplopia, and memory loss for 1 month. Cranial nerve examination revealed bilateral upward gaze limitation with convergence impairment, which is known as Parinaud syndrome. Magnetic resonance images revealed a mass in the pineal gland with a coexisting mass within the enlarged sella fossa. Hormone analysis revealed hyperprolactinemia. The pineal mass was removed without injuring the hypothalamus, brain stem, or any neighboring vessels. Pathology examination confirmed the diagnosis of diffuse large B-cell lymphoma (DLBCL) involving the pineal gland. After further studies, the pineal lymphoma was determined to be a secondary tumor from a gastric primary tumor. The patient died 6 months after diagnosis due to systemic progression of DLBCL.Although the mechanistic link between hyperprolactinemia and lymphoma progression has not been clarified on a clinical basis, high prolactin levels may contribute to the rapid progression and therapeutic resistance of the lymphoma. PMID:26937937

  15. Tumor Shrinkage Assessed by Volumetric MRI in Long-Term Follow-Up After Fractionated Stereotactic Radiotherapy of Nonfunctioning Pituitary Adenoma

    SciTech Connect

    Kopp, Christine; Theodorou, Marilena; Poullos, Nektarios; Jacob, Vesna; Astner, Sabrina T.; Molls, Michael; Grosu, Anca-Ligia

    2012-03-01

    Purpose: To evaluate tumor control and side effects associated with fractionated stereotactic radiotherapy (FSRT) in the management of residual or recurrent nonfunctioning pituitary adenomas (NFPAs). Methods and Materials: We assessed exact tumor volume shrinkage in 16 patients with NFPA after FSRT. All patients had previously undergone surgery. Gross tumor volume (GTV) was outlined on contrast-enhanced magnetic resonance imaging (MRI) before and median 63 months (range, 28-100 months) after FSRT. MRI was performed as an axial three-dimensional gradient echo T1-weighted sequence at 1.6-mm slice thickness without gap (3D MRI). Results: Mean tumor size of all 16 pituitary adenomas before treatment was 7.4 mL (3.3-18.9 mL). We found shrinkage of the treated pituitary adenoma in all patients. Within a median follow-up of 63 months (28-100 months) an absolute mean volume reduction of 3.8 mL (0.9-12.4 mL) was seen. The mean relative size reduction compared with the volume before radiotherapy was 51% (22%-95%). Shrinkage measured by 3D MRI was greater at longer time intervals after radiotherapy. A strong negative correlation between the initial tumor volume and the absolute volume reduction after FSRT was found. There was no correlation between tumor size reduction and patient age, sex, or number of previous surgeries. Conclusions: By using 3D MRI in all patients undergoing FSRT of an NFPA, tumor shrinkage is detected. Our data demonstrate that volumetric assessment based on 3D MRI adds additional information to routinely used radiological response measurements. After FSRT a mean relative size reduction of 51% can be expected within 5 years.

  16. Hypothalamic corticotropin-releasing factor immunoreactivity is reduced during induction of pituitary tumors by chronic estrogen treatment

    SciTech Connect

    Haas, D.A.; Borgundvaag, B.; Sturtridge, W.C.; George, S.R.

    1987-11-02

    The role that estrogen plays in the regulation of corticotropin-releasing factor (CRF) is not known. A radioimmunoassay specific for rat CRF was utilized to measure the CRF-like immunoreactivity (CRF-ir) in the hypothalamus of ovariectomized rats treated with estradiol for periods up to 12 weeks. Compared to ovariectomized controls, estradiol treatment resulted in significantly reduced CRF-ir after 3 and 12 weeks, although no significant change was seen after 8 weeks. Anterior pituitary (AP) weight was greatly increased by estradiol treatment at all time points studied. Bromocriptine treatment for the last 3 weeks of the 12-week period, or removal of estradiol for 3 weeks after 9 weeks of treatment did not reverse the changes in CRF-ir even though significant regressions of tumor size was achieved. There was no correlation between AP weight and CRF-ir in individual animals. These data show that chronic treatment with estrogen reduced hypothalamic CRF-ir content. Neither a direct estrogenic effect or an indirect effect mediated through alterations in the adenohypophysis could be ruled out. 21 references, 3 figures.

  17. Mechanisms for stimulation of rat anterior pituitary cells by arginine and other amino acids.

    PubMed Central

    Villalobos, C; Núñez, L; García-Sancho, J

    1997-01-01

    1. Arginine and other amino acids are secretagogues for growth hormone and prolactin in the intact animal, but the mechanism of action is unclear. We have studied the effects of amino acids on cytosolic free calcium concentration ([Ca2+]i) in single rat anterior pituitary (AP) cells. Arginine elicited a large increase of [Ca2+]i) in about 40% of all the AP cells, suggesting that amino acids may modulate hormone secretion by acting directly on the pituitary. 2. Cell typing by immunofluorescence of the hormone the cells store showed that the arginine-sensitive cells are distributed uniformly within all the five AP cell types. The arginine-sensitive cells overlapped closely with the subpopulation of cells sensitive to thyrotrophin-releasing hormone. 3. Other cationic as well as several neutral (dipolar) amino acids had the same effect as arginine. The increase of [Ca2+]i was dependent on extracellular Ca2+ and blocked by dihydropyridine, suggesting that it is due to Ca2+ influx through L-type voltage-gated Ca2+ channels. The [Ca2+]i increase was also blocked by removal of extracellular Na+ but not by tetrodotoxin. The substrate specificity for stimulation of AP cells resembled closely that of the amino acid transport system B0+. We propose that electrogenic amino acid influx through this pathway depolarizes the plasma membrane with the subsequent activation of voltage-gated Ca2+ channels and Ca2+ entry. 4. Amino acids also stimulated prolactin secretion in vitro with a similar substrate specificity to that found for the [Ca2+]i increase. Existing data on the stimulation of secretion of other hormones by amino acids suggest that a similar mechanism could apply to other endocrine glands. PMID:9263921

  18. Locally produced estrogen through aromatization might enhance tissue expression of pituitary tumor transforming gene and fibroblast growth factor 2 in growth hormone-secreting adenomas.

    PubMed

    Ozkaya, Hande Mefkure; Comunoglu, Nil; Keskin, Fatma Ela; Oz, Buge; Haliloglu, Ozlem Asmaz; Tanriover, Necmettin; Gazioglu, Nurperi; Kadioglu, Pinar

    2016-06-01

    Aromatase, a key enzyme in local estrogen synthesis, is expressed in different pituitary tumors including growth hormone (GH)-secreting adenomas. We aimed to evaluate aromatase, estrogen receptor α (ERα), estrogen receptor β (ERβ), pituitary tumor transforming gene (PTTG), and fibroblast growth factor 2 (FGF2) expressions in GH-secreting adenomas, and investigate their correlation with clinical, pathologic, and radiologic parameters. This cross-sectional study was conducted in a tertiary center in Turkey. Protein expressions were determined via immunohistochemical staining in ex vivo tumor samples of 62 patients with acromegaly and ten normal pituitary tissues. Concordantly increased aromatase, PTTG, and FGF2 expressions were detected in the tumor samples as compared with controls (p < 0.001 for all). None of the tumors expressed ERα while ERβ was detected only in mixed somatotroph adenomas. Aromatase, ERβ, PTTG expressions were not significantly different between patients with and without remission (p > 0.05 for all). FGF2 expression was significantly higher in patients without postoperative and late remission (p = 0.002 and p = 0.012, respectively), with sphenoid bone invasion, optic chiasm compression, and somatostatin analog resistance (p = 0.005, p = 0.033, and p = 0.013, respectively). Aromatase, PTTG and FGF2 expressions were positively correlated with each other (r = 0,311, p = 0.008 for aromatase, FGF2; r = 0.380, p = 0.001 for aromatase, PTTG; r = 0.400, p = 0.001 for FGF2, PTTG). PTTG-mediated FGF2 upregulation is associated with more aggressive tumor features in patients with acromegaly. Also, locally produced estrogen through aromatization might have a role in this phenomenon. PMID:26578364

  19. Pituitary gland

    MedlinePlus Videos and Cool Tools

    ... gland is the hypothalamus. The hypothalamus decides which hormones the pituitary should release by sending it either ... the hypothalamus, the pituitary gland releases the following hormones: GH (growth hormone) – increases size of muscle and ...

  20. Anatomy, Physiology, and Laboratory Evaluation of the Pituitary Gland.

    PubMed

    Hong, Gregory K; Payne, Spencer C; Jane, John A

    2016-02-01

    The pituitary gland functions prominently in the control of most endocrine systems in the body. Diverse processes such as metabolism, growth, reproduction, and water balance are tightly regulated by the pituitary in conjunction with the hypothalamus and various downstream endocrine organs. Benign tumors of the pituitary gland are the primary cause of pituitary pathology and can result in inappropriate secretion of pituitary hormones or loss of pituitary function. First-line management of clinically significant tumors often involves surgical resection. Understanding of normal pituitary physiology and basic testing strategies to assess for pituitary dysfunction should be familiar to any skull base surgeon. PMID:26614827

  1. Interaction of MSC with tumor cells.

    PubMed

    Melzer, Catharina; Yang, Yuanyuan; Hass, Ralf

    2016-01-01

    Tumor development and tumor progression is not only determined by the corresponding tumor cells but also by the tumor microenvironment. This includes an orchestrated network of interacting cell types (e.g. immune cells, endothelial cells, fibroblasts, and mesenchymal stroma/stem cells (MSC)) via the extracellular matrix and soluble factors such as cytokines, chemokines, growth factors and various metabolites. Cell populations of the tumor microenvironment can interact directly and indirectly with cancer cells by mutually altering properties and functions of the involved partners. Particularly, mesenchymal stroma/stem cells (MSC) play an important role during carcinogenesis exhibiting different types of intercellular communication. Accordingly, this work focusses on diverse mechanisms of interaction between MSC and cancer cells. Moreover, some functional changes and consequences for both cell types are summarized which can eventually result in the establishment of a carcinoma stem cell niche (CSCN) or the generation of new tumor cell populations by MSC-tumor cell fusion. PMID:27608835

  2. Synchronous pituitary adenoma and pituicytoma.

    PubMed

    Neidert, Marian C; Leske, Henning; Burkhardt, Jan-Karl; Kollias, Spyros S; Capper, David; Schrimpf, Daniel; Regli, Luca; Rushing, Elisabeth J

    2016-01-01

    Pituicytoma is a rare benign neoplasm arising in the sellar region, usually found in the posterior lobe and/or pituitary stalk. Here, we report the case of a 67-year-old woman who presented with bitemporal hemianopsia and visual impairment accompanied by mildly elevated prolactin. Pathologic and molecular examination of the tissue removed transsphenoidally revealed 2 distinct tumors: pituitary adenoma and pituicytoma. To the best of our knowledge, histologically proven pituicytoma and pituitary adenoma have never been reported together. PMID:26476569

  3. THE ONTOGENY OF INSULIN-LIKE GROWTH FACTOR-I (IGF-I) MODULATION OF GH SECRETION FROM PORCINE ANTERIOR PITUITARY CELLS IN CULTURE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ontogeny of IGF-I modulation of GH secretion from the anterior pituitary was studied. Anterior pituitary cells collected from 110 day old fetuses (n =4), 2- (n = 7), 4- (n =8) and 6- (n = 7) month old gilts were studied in primary culture. On day 4 of culture, 100,000 cells/well were challenge...

  4. Cell Type-Specific Sexual Dimorphism in Rat Pituitary Gene Expression During Maturation.

    PubMed

    Bjelobaba, Ivana; Janjic, Marija M; Kucka, Marek; Stojilkovic, Stanko S

    2015-07-01

    The most obvious functional differences between mammalian males and females are related to the control of reproductive physiology and include patterns of GnRH and gonadotropin release, the timing of puberty, sexual and social behavior, and the regulation of food intake and body weight. Using the rat as the best-studied mammalian model for maturation, we examined the expression of major anterior pituitary genes in five secretory cell types of developing males and females. Corticotrophs show comparable Pomc profiles in both sexes, with the highest expression occurring during the infantile period. Somatotrophs and lactotrophs also exhibit no difference in Gh1 and Prl profiles during embryonic to juvenile age but show the amplification of Prl expression in females and Gh1 expression in males during peripubertal and postpubertal ages. Gonadotrophs exhibit highly synchronized Lhb, Fshb, Cga, and Gnrhr expression in both sexes, but the peak of expression occurs during the infantile period in females and at the end of the juvenile period in males. Thyrotrophs also show different developmental Tshb profiles, which are synchronized with the expression of gonadotroph genes in males but not in females. These results indicate the lack of influence of sex on Pomc expression and the presence of two patterns of sexual dimorphism in the expression of other pituitary genes: a time shift in the peak expression during postnatal development, most likely reflecting the perinatal sex-specific brain differentiation, and modulation of the amplitude of expression during late development, which is secondary to the establishment of the hypothalamic-pituitary-gonadal and -thyroid axes. PMID:26063874

  5. Kisspeptin-1 directly stimulates LH and GH secretion from goldfish pituitary cells in a Ca(2+)-dependent manner.

    PubMed

    Chang, John P; Mar, Alan; Wlasichuk, Michael; Wong, Anderson O L

    2012-10-01

    It has been established that kisspeptin regulates reproduction via stimulation of hypothalamic gonadotropin-releasing hormone (GnRH) secretion, which then induces pituitary luteinizing hormone (LH) release. Kisspeptin also directly stimulates pituitary hormone release in some mammals. However, in goldfish, whether kisspeptin directly affects pituitary hormone release is controversial. In this study, synthetic goldfish kisspeptin-1((1-10)) (gKiss1) enhances LH and growth hormone (GH) release from primary cultures of goldfish pituitary cells in column perifusion. gKiss1 stimulation of LH and GH secretion were still manifested in the presence of the two native goldfish GnRHs, salmon (s)GnRH (goldfish GnRH-3) and chicken (c)GnRH-II (goldfish GnRH-2), but were attenuated by two voltage-sensitive calcium channel blockers, verapamil and nifedipine. gKiss-induced increases in intracellular Ca(2+) in Fura-2AM pre-loaded goldfish pars distalis cells were also inhibited by nifedipine. These results indicate that, in goldfish, (1) direct gKiss1 actions on pituitary LH and GH secretion exist, (2) these actions are independent of GnRH and (3) they involve Ca(2+) signalling. PMID:22885559

  6. Microgravity associated changes in pituitary growth hormone (GH) cells prepared from rats flown on Space Lab 3

    NASA Technical Reports Server (NTRS)

    Hymer, W. C.; Farrington, M.; Hayes, C.; Grindeland, R.; Fast, T.

    1985-01-01

    The effect of microgravity on the release of pituitary growth hormone (GH) in rats is studied. The pituitary glands from six adult rats exposed to microgravity are analyzed for in vitro and in vivo changes in pituitary growth hormone cells. The GH cell functions in the somatotrophs of flight rats are compared to a control group. The two assay procedures employed in the experiment are described. It is observed that intracellular levels of GH are two to three times greater in the flight rats than in the control group; however, the amount of GH released from the somatotrophs is 1.11 + or - 0.4 micrograms for the flight rats and 1.85 + or - 1.3 micrograms for the control rats.

  7. Rapid enlargement of an intracranial germ cell tumor after gonadotropin hormone therapy.

    PubMed

    Sasagawa, Yasuo; Tachibana, Osamu; Nakagawa, Athushi; Nakada, Satoko; Nojima, Takayuki; Koya, Daisuke; Iizuka, Hideaki

    2016-09-01

    We report a case of an intracranial germ cell tumor (iGCT) that showed rapid enlargement after human chorionic gonadotropin (hCG) hormone therapy for pituitary hypogonadism. A 16-year-old boy presented with headache and was diagnosed with a suprasellar tumor. He was initially observed without surgery. Intranasal desmopressin therapy was started for central diabetes insipidus, but there was no change in the tumor size on MRI. The diagnosis of the tumor remained unknown for 4years. Levels of serum gonadotropin hormones (follicle-stimulating and luteinizing hormone) and testosterone progressively decreased, and the patient developed pituitary hypogonadism and complained about his undeveloped beard, lack of underarm hair, and erectile dysfunction. Intramuscular gonadotropin injection (hCG 5000U×2/week) was started at age 20. Eight months after the first gonadotropin injection, the MRI showed tumor growth with vivid enhancement. Craniotomy was performed and the tumor was partially resected. The histological diagnosis was immature teratoma. After surgery, the patient was treated with 5 cycles of chemotherapy with carboplatin and etoposide. He also received radiation therapy of 50Gy (20Gy tumor bed and 30Gy whole ventricles) to the residual tumor, after which the tumor decreased in size. We postulate that iGCT may be at risk of progression during hCG hormone therapy. Thus, careful monitoring is required for a patient with iGCT who receives this therapy. PMID:27050912

  8. Palifosfamide in Treating Patients With Recurrent Germ Cell Tumors

    ClinicalTrials.gov

    2015-06-11

    Adult Central Nervous System Germ Cell Tumor; Adult Teratoma; Malignant Extragonadal Germ Cell Tumor; Malignant Extragonadal Non-Seminomatous Germ Cell Tumor; Extragonadal Seminoma; Recurrent Malignant Testicular Germ Cell Tumor; Recurrent Ovarian Germ Cell Tumor; Stage IV Extragonadal Non-Seminomatous Germ Cell Tumor; Stage IV Extragonadal Seminoma; Stage IV Ovarian Germ Cell Tumor

  9. [Treatment of pituitary adenomas].

    PubMed

    Mezosi, Emese; Nemes, Orsolya

    2009-09-27

    According to epidemiological studies, the prevalence of pituitary adenomas is 16.5% and the majority of them are "incidentalomas". The symptoms of pituitary disorders are often non-specific; disturbances of pituitary function, compression symptoms, hypophysis apoplexy or accidental findings may help the diagnosis. The hormonal evaluation of pituitary adenomas is different from the algorithm used in the disorders of peripheral endocrine organs. The first-line therapy of prolactinomas are the dopamine agonists, and the aims of the treatment are to normalize the prolactin level, restore fertility in child-bearing age, decrease tumor mass, save or improve the residual pituitary function and inhibit the relapse of the disease. The available dopamine agonists in Hungary are bromocriptine and quinagolide. In case of tumors with good therapeutic response, medical therapy can be withdrawn after 3-5 years; hyperprolactinemia will not recur in 2/3 of these patients. Neurosurgery is the primary therapy of GH-, ACTH-, TSH-producing and inactive adenomas. In the last decades, significant improvement has been reached in surgical procedures, resulting in low mortality rates. Acromegalic patients with unresectable tumors have a great benefit from somatostatin analog treatment. The growth hormone receptor antagonist pegvisomant is the newest modality for the treatment of acromegaly. The medical therapy of Cushing's disease is still based on the inhibition of steroid production. A new, promising somatostatin analog, pasireotide is evaluated in clinical trials. The rare TSH-producing tumor can respond to both dopamine agonist and somatostatin analog therapy. The application of conventional radiotherapy has decreased; radiotherapy is mainly used in the treatment of invasive, incurable or malignant tumors. Further studies are needed to elucidate the exact role of radiosurgery and fractionated stereotaxic irradiation in the treatment of pituitary tumors. PMID:19758960

  10. Multiple splice variants of the pituitary adenylate cyclase-activating polypeptide type 1 receptor detected by RT-PCR in single rat pituitary cells.

    PubMed

    Bresson-Bépoldin, L; Jacquot, M C; Schlegel, W; Rawlings, S R

    1998-10-01

    Alternative splicing of the rat type 1 pituitary adenylate cyclase-activating polypeptide (PACAP) receptor (PVR1) produces variants that couple either to both adenylyl cyclase (AC) and phospholipase C (PLC) (PVR1 short, PVR1 hop, PVR1 hiphop), or to AC alone (PVR1 hip). We have previously shown that populations of clonal alphaT3-1 gonadotrophs express PVR1 hop and PVR1 short mRNAs, whereas clonal GH4C1 somatotrophs do not. Here we have used the single cell RT-PCR technique to investigate whether normal rat gonadotrophs and somatotrophs express PVR1 mRNA, whether a single cell co-expresses multiple splice variant forms, and whether differential PVR1 mRNA expression correlates with differences in PACAP-stimulated Ca2+ signalling. We found that individual rat gonadotrophs expressed mRNA either for PVR1 hop, for PVR1 short, or co-expressed the two forms. Although we found no differences between the splice variant(s) expressed and the characteristics of PACAP-stimulated Ca2+ responses, the expression of PVR1 mRNA is consistent with the known PACAP stimulation of the PLC system in gonadotrophs. Individual rat somatotrophs also expressed PVR1 hop or PVR1 short (but not PVR1 hip) mRNAs although these forms were never co-expressed. The expression of PVR1 mRNA in somatotrophs can explain in part the activation by PACAP of the AC system in such cells. In conclusion, the single cell RT-PCR technique was used to demonstrate expression of multiple PVR1 splice variants in single identified pituitary cells. These findings open up important questions on the role of alternative splicing in cell biology. PMID:9801454

  11. Differential signaling of the GnRH receptor in pituitary gonadotrope cell lines and prostate cancer cell lines

    PubMed Central

    Sviridonov, Ludmila; Dobkin-Bekman, Masha; Shterntal, Boris; Przedecki, Fiorenza; Formishell, Linor; Kravchook, Shani; Navi, Liat Rahamim-Ben; Bar-Lev, Tali Hana; Kazanietz, Marcelo G.; Yao, Zhong; Seger, Rony; Naor, Zvi

    2014-01-01

    The GnRH receptor (GnRHR) mediates the pituitary functions of GnRH, as well as its anti-proliferative effects in sex hormone-dependent cancer cells. Here we compare the signaling of GnRHR in pituitary gonadotrope cell lines vs. prostate cancer cell lines. We first noticed that the expression level of PKCα, PKCβII and PKCε is much higher in αT3-1 and LβT2 gonadotrope cell lines vs. LNCaP and DU-145 cell lines, while the opposite is seen for PKCδ. Activation of PKCα, PKCβII and PKCε by GnRH is relatively transient in αT3-1 and LβT2 gonadotrope cell lines and more prolonged in LNCaP and DU-145 cell lines. On the otherhand, the activation and re-distribution of the above PKCs by PMA was similar for both gonadotrope cell lines and prostate cancer cell lines. Activation of ERK1/2 by GnRH and PMA was robust in the gonadotrope cell lines, with a smaller effect observed in the prostate cancer cell lines. The Ca2+ ionophore A23187 stimulated ERK1/2 in gonadotrope cell lines but not in prostate cancer cell lines. GnRH, PMA and A23187 stimulated JNK activity in gonadotrope cell lines, with a more sustained effect in prostate cancer cell lines. Sustained activation of p38 was observed for PMA and A23187 in Du-145 cells, while p38 activation by GnRH, PMA and A23187 in LβT2 cells was transient. Thus, differential expression and re-distribution of PKCs by GnRH and the transient vs. the more sustained nature of the activation of the PKC-MAPK cascade by GnRH in gonadotrope cell lines vs. prostate cancer cell lines respectively, may provide the mechanistic basis for the cell context-dependent differential biological responses observed in GnRH interaction with pituitary gonadotropes vs. prostate cancer cells. PMID:23380421

  12. Maintenance of the Extracellular Matrix in Rat Anterior Pituitary Gland: Identification of Cells Expressing Tissue Inhibitors of Metalloproteinases

    PubMed Central

    Azuma, Morio; Tofrizal, Alimuddin; Maliza, Rita; Batchuluun, Khongorzul; Ramadhani, Dini; Syaidah, Rahimi; Tsukada, Takehiro; Fujiwara, Ken; Kikuchi, Motoshi; Horiguchi, Kotaro; Yashiro, Takashi

    2015-01-01

    The extracellular matrix (ECM) is important in creating cellular environments in tissues. Recent studies have demonstrated that ECM components are localized in anterior pituitary cells and affect cell activity. Thus, clarifying the mechanism responsible for ECM maintenance would improve understanding of gland function. Tissue inhibitors of metalloproteinases (TIMPs) are endogenous inhibitors of matrix metalloproteinases and participate in ECM degradation. In this study, we investigated whether cells expressing TIMPs are present in rat anterior pituitary gland. Reverse transcription polymerase chain reaction was used to analyze expression of the TIMP family (TIMP1-4), and cells producing TIMPs in the gland were identified by using in situ hybridization. Expression of TIMP1, TIMP2, and TIMP3 mRNAs was detected, and the TIMP-expressing cells were located in the gland. The TIMP-expressing cells were also investigated by means of double-staining with in situ hybridization and immunohistochemical techniques. Double-staining revealed that TIMP1 mRNA was expressed in folliculostellate cells. TIMP2 mRNA was detected in folliculostellate cells, prolactin cells, and thyroid-stimulating hormone cells. TIMP3 mRNA was identified in endothelial cells, pericytes, novel desmin-immunopositive perivascular cells, and folliculostellate cells. These findings indicate that TIMP1-, TIMP2-, and TIMP3-expressing cells are present in rat anterior pituitary gland and that they are involved in maintaining ECM components. PMID:26855451

  13. General Information about Extragonadal Germ Cell Tumors

    MedlinePlus

    ... Germ Cell Tumors Treatment (PDQ®)–Patient Version General Information About Extragonadal Germ Cell Tumors Go to Health ... the PDQ Adult Treatment Editorial Board . Clinical Trial Information A clinical trial is a study to answer ...

  14. General Information about Ovarian Germ Cell Tumors

    MedlinePlus

    ... Germ Cell Tumors Treatment (PDQ®)–Patient Version General Information About Ovarian Germ Cell Tumors Go to Health ... the PDQ Adult Treatment Editorial Board . Clinical Trial Information A clinical trial is a study to answer ...

  15. Patient-Derived Antibody Targets Tumor Cells

    Cancer.gov

    An NCI Cancer Currents blog on an antibody derived from patients that killed tumor cells in cell lines of several cancer types and slowed tumor growth in mouse models of brain and lung cancer without evidence of side effects.

  16. Affinity isolation of cultured tumor cells by means of drugs and hormones covalently bound to glass and Sepharose beads.

    PubMed Central

    Venter, B R; Venter, J C; Kaplan, N O

    1976-01-01

    Isoproterenol, corticotropin (ACTH), and triodothyronine immobilized on glass and Sepharose beads by diazotization procedures have been shown to interact with cultured tumor cells of "target tissue" origin. Cells used were rat glioma cells (C6), rat adrenal tumor cells (Y-1), and rat pituitary tumor cells (GH3). The rat glioma cells bound principally to immobilized isoproterenol, whereas the rat adrenal tumor cells bound to immobilized corticotropin, and rat pituitary tumor cells bound to immobilized triiodothyronine. Binding was inhibited by preincubation of the cells in soluble drug or hormone. With C6 cells there was a positive correlation between adenylate cyclase [ATP pyrophosphate-lyase (cyclizing, EC 4.6.1.1] stimulation and the degree of binding to the immobilized isoproterenol. Norepinephrine, bound through the ethanolamine side chain via an amide linkage, did not bind cells, demonstrating specific structural requirements for drug-cell interactions. HeLa cells were shown to bind tightly to diphtheria toxin coupled to Sepharose beads via an amide bond. This binding was inhibited by prior incubation of the Sepharose toxin with purified antitoxin. Toxin bound to Sepharose via an azo bond did not bind cells. These data suggest that the cell affinities are due to cell surface receptors interacting with the immobilized drugs and hormones, and that the observed affinities possibly reflect the relative receptor complement of these cells. Images PMID:180534

  17. Central diabetes insipidus as a very late relapse limited to the pituitary stalk in Langerhans cell histiocytosis.

    PubMed

    Nakagawa, Shunsuke; Shinkoda, Yuichi; Hazeki, Daisuke; Imamura, Mari; Okamoto, Yasuhiro; Kawakami, Kiyoshi; Kawano, Yoshifumi

    2016-07-01

    Central diabetes insipidus (CDI) and relapse are frequently seen in multifocal Langerhans cell histiocytosis (LCH). We present two females with multifocal LCH who developed CDI 9 and 5 years after the initial diagnosis, respectively, as a relapse limited to the pituitary stalk. Combination chemotherapy with cytarabine reduced the mass in the pituitary stalk. Although CDI did not improve, there has been no anterior pituitary hormone deficiency (APHD), neurodegenerative disease in the central nervous system (ND-CNS) or additional relapse for 2 years after therapy. It was difficult to predict the development of CDI in these cases. CDI might develop very late in patients with multifocal LCH, and therefore strict follow-up is necessary, especially with regard to symptoms of CDI such as polydipsia and polyuria. For new-onset CDI with LCH, chemotherapy with cytarabine might be useful for preventing APHD and ND-CNS. PMID:27089406

  18. Mechanisms of desensitization of the adrenocorticotropin response to arginine vasopressin in ovine anterior pituitary cells.

    PubMed

    Hassan, A; Mason, D

    2005-01-01

    Arginine vasopressin (AVP) stimulates adrenocorticotropin (ACTH) secretion from corticotroph cells of the anterior pituitary via activation of the V1b vasopressin receptor, a member of the G protein-coupled receptor (GPCR) family. Recently, we have shown that treatment of ovine anterior pituitary cells with AVP for short periods results in reduced responsiveness to subsequent stimulation with AVP. The aim of this study was to investigate mechanisms involved in this desensitization process. Among the GPCR family, rapid desensitization is commonly mediated by receptor phosphorylation, with resensitization being mediated by internalization and subsequent dephosphorylation of the receptors by protein phosphatases. Since desensitization of V1a vasopressin receptors is mediated by protein kinase C-mediated receptor phosphorylation, we investigated the involvement of this enzyme in desensitization of the ACTH response to AVP. Treatment of perifused ovine anterior pituitary cells with the specific protein kinase C (PKC) activator 1,2-dioctanoyl-sn-glycerol (300 microM) did not induce any reduction in response to a subsequent 5-min stimulation with 100 nM AVP, despite potently stimulating ACTH secretion. Likewise, the results obtained using the PKC inhibitor Ro 31-8220 were not consistent with involvement of PKC in AVP desensitization: 2 microM Ro 31-8220 did not reduce the ability of a 10 nM AVP pretreatment to induce desensitization to a subsequent stimulation with 100 nM AVP. Pharmacologic blockade of receptor internalization by treatment with 0.25 mg/ml concanavalin A significantly impaired the ability of a 15-min pretreatment with 10 nM AVP to induce desensitization, rather than affecting resensitization. Treatment with 10 nM okadaic acid, an inhibitor of protein phosphatase 1 and 2A, had no effect on either resensitization or desensitization. In contrast, inhibition of protein phosphatase 2B (PP2B) with 1 microM FK506 decreased the rate of resensitization: complete

  19. Null cell adenomas of the pituitary gland: an institutional review of their clinical imaging and behavioral characteristics.

    PubMed

    Balogun, James A; Monsalves, Eric; Juraschka, Kyle; Parvez, Kashif; Kucharczyk, Walter; Mete, Ozgur; Gentili, Fred; Zadeh, Gelareh

    2015-03-01

    The aim of the study was to establish if the null cell adenoma (NCA) forms a distinct subgroup with unique clinicopathological characteristics within the nonfunctioning pituitary adenoma group particularly in relation to the silent gonadotroph adenomas (SGAs). We identified 31 patients with the pathological diagnosis of NCA verified by routine histology and immunohistochemistry with distinct differentiation from SGAs by an established negative testing for SF-1 at the Toronto Western Hospital between December 2004 and August 2010. We reviewed their demographic data, clinical features, magnetic resonance imaging, and the histologic variables: MIB-1, FGFR4, and P27. We compared these to 63 SGAs identified within the same period. All the NCAs were macroadenomas with diameter ranging from 15-57 mm and tumor volumes between 1.95-53.5 mm(3). Preoperative cavernous sinus tumor growth was able to predict the presence of a residual after surgery (p = 0.023). Furthermore, preoperative cavernous sinus extension (p = 0.002) and negative P27 expression (p = 0.035) were able to independently predict the subsequent growth of the postoperative tumor residual. Comparing the NCA to SGA, we found that MIB-1 was higher in NCA (mean ± SD = 3.43 ± 2.76 %) compared to SGAs (mean ± SD = 2.49 ± 1.41 %) (p = 0.044). The preoperative and postoperative tumor volume doubling times (TVDTs) displayed a negative correlation in the SGA (r = -0.855, p = 0.002) while in the NCA, a positive correlation was evident (r = 0.718, p = 0.029). Our study suggests that the NCAs are a distinct group with differing behavioral characteristics from the SGAs. It also appears that the finding of cavernous sinus extension on preoperative imaging and a negative P27 expression on immunohistochemistry in NCAs may be valuable tools in predicting residual tumor growth which may impact on postoperative care. PMID:25403448

  20. Differential tissue regulation of the insulin-like growth factors in rats bearing the MStT/W15 pituitary tumor.

    PubMed

    Gelato, M C; Vassalotti, J; Spatola, E; Rutherford, C; Marsh, K; Carlson, H E

    1992-12-01

    The content of insulin-like growth factors, IGF-I and IGF-II, was measured in tissues of rats bearing a transplantable mammosomatotrophic tumor, MStT/W15. Serum IGF-I was elevated in tumor-implanted rats [2,557 +/- (SE) 419 vs. 891 +/- 100 ng/ml], and tumor tissue concentrations of IGF-I were increased (321 +/- 16 ng/g) in comparison to control liver tissue (160 +/- 5 ng/g) or control pituitary (80 +/- 3 ng/g). The IGF-I levels were significantly increased in most peripheral tissues in the tumor-bearing rats with the exception of the liver. In support of this finding, messenger RNA for prepro IGF-I was likewise not increased in the livers of tumor-bearing rats, nor was there an increase in the growth hormone-dependent IGF-binding protein, BP-3, in the liver or serum of these animals. All tumors had detectable levels of prepro IGF-I mRNA which was, however, less than 50% of that noted in normal control liver. The tumors also expressed an IGF-BP which was identified as IGF-BP-2 by immunoblotting. Serum concentrations of IGF-II were similar in control and tumor-bearing animals (approximately 70 ng/ml). IGF-II levels in the tumor (90 +/- 5 ng/g) were significantly higher than levels in control liver (34 +/- 2 ng/g), but similar to those found in normal pituitary (165 +/- 24 ng/g). In peripheral tissues, IGF-II concentrations were selectively increased in skeletal muscle and heart of tumor-bearing rats. These data demonstrate tissue-specific regulation of IGF-I and IGF-II. Paradoxically, the liver does not appear to be stimulated over control levels by high serum growth hormone levels, since neither IGF-I peptide, IGF-I mRNA, nor IGF-BP-3 levels are increased in livers of tumor-bearing rats. This suggests that the increase in serum IGF-I in these animals is due to increased production of IGF-I by the tumors themselves and by nonhepatic peripheral tissues and further that hepatic responsiveness to growth hormone is diminished in these tumor-bearing animals. PMID:1369583

  1. Localisation and semi-quantitative measurement of lipocortin 1 in rat anterior pituitary cells by fluorescence-activated cell analysis/sorting and electron microscopy.

    PubMed

    Christian, H C; Flower, R J; Morris, J F; Buckingham, J C

    1999-09-01

    Lipocortin 1 (LC1, also called annexin 1), a Ca2(+)- and phospholipid-binding protein, is an important mediator of glucocorticoid action in the anterior pituitary gland. Previous studies based on immunoprecipitation and Western blot analysis suggest that LC1 is found intracellularly both in the cytoplasm and in association with membranes and also on the cell surface where it attaches to the membrane by a Ca2(+)-dependent mechanism. However, as yet it is unclear which anterior pituitary cell types express the protein. Accordingly, we have developed a method based on a combination of fluorescence activated cell (FAC) analysis/sorting and electron microscopy to detect and quantify intracellular LC1 in rat anterior pituitary cells and to identify the cell types in which it is expressed. In addition, we have measured cell surface LC1 and examined the influence of glucocorticoids on the cellular disposition of the protein. Anterior pituitary cells were dispersed with collagenase. For experiments measuring intracellular LC1, three cell fixation/permeabilisation methods were examined initially, i.e. (1) Zamboni's fluid (30 min) and Triton-X-100 (0.12%, 1 or 12 h); (2) paraformaldehyde (2%, 1 h) and Triton-X-100 (0.2%, 10 min); and (3) paraformaldehyde (0.2%, 15 min) and saponin (0.1%, 5 min). The protocol using paraformaldehyde/Triton-X-100 provided optimal preservation of cell ultrastructure and of LC1 immunoreactivity (ir-LC1) while also effectively permeabilising the cells; it was therefore used in subsequent studies. Using an anti-LC1 monoclonal antibody as a probe, 82+/-5% of the secretory cells in the heterogeneous anterior pituitary cell preparation were shown by FAC analysis to display specific fluorescence for intracellular ir-LC1. Morphological analysis and immunogold-histochemistry of cells separated by FAC sorting identified corticotrophs, lactotrophs, somatotrophs and gonadotrophs in the population displaying LC1 immunofluorescence. LC1 was also detected on

  2. Cloning of Porcine Pituitary Tumor Transforming Gene 1 and Its Expression in Porcine Oocytes and Embryos.

    PubMed

    Xie, Bingkun; Qin, Zhaoxian; Liu, Shuai; Nong, Suqun; Ma, Qingyan; Chen, Baojian; Liu, Mingjun; Pan, Tianbiao; Liao, D Joshua

    2016-01-01

    The maternal-to-embryonic transition (MET) is a complex process that occurs during early mammalian embryogenesis and is characterized by activation of the zygotic genome, initiation of embryonic transcription, and replacement of maternal mRNA with embryonic mRNA. The objective of this study was to reveal the temporal expression and localization patterns of PTTG1 during early porcine embryonic development and to establish a relationship between PTTG1 and the MET. To achieve this goal, reverse transcription-polymerase chain reaction (RT-PCR) was performed to clone porcine PTTG1. Subsequently, germinal vesicle (GV)- and metaphase II (MII)-stage oocytes, zygotes, 2-, 4-, and 8-cell-stage embryos, morulas, and blastocysts were produced in vitro and their gene expression was analyzed. The results revealed that the coding sequence of porcine PTTG1 is 609-bp in length and that it encodes a 202-aa polypeptide. Using qRT-PCR, PTTG1 mRNA expression was observed to be maintained at high levels in GV- and MII-stage oocytes. The transcript levels in oocytes were also significantly higher than those in embryos from the zygote to blastocyst stages. Immunohistochemical analyses revealed that porcine PTTG1 was primarily localized to the cytoplasm and partially localized to the nucleus. Furthermore, the PTTG1 protein levels in MII-stage oocytes and zygotes were significantly higher than those in embryos from the 2-cell to blastocyst stage. After fertilization, the level of this protein began to decrease gradually until the blastocyst stage. The results of our study suggest that porcine PTTG1 is a new candidate maternal effect gene (MEG) that may participate in the processes of oocyte maturation and zygotic genome activation during porcine embryogenesis. PMID:27058238

  3. Cloning of Porcine Pituitary Tumor Transforming Gene 1 and Its Expression in Porcine Oocytes and Embryos

    PubMed Central

    Liu, Shuai; Nong, Suqun; Ma, Qingyan; Chen, Baojian; Liu, Mingjun; Pan, Tianbiao; Liao, D. Joshua

    2016-01-01

    The maternal-to-embryonic transition (MET) is a complex process that occurs during early mammalian embryogenesis and is characterized by activation of the zygotic genome, initiation of embryonic transcription, and replacement of maternal mRNA with embryonic mRNA. The objective of this study was to reveal the temporal expression and localization patterns of PTTG1 during early porcine embryonic development and to establish a relationship between PTTG1 and the MET. To achieve this goal, reverse transcription-polymerase chain reaction (RT-PCR) was performed to clone porcine PTTG1. Subsequently, germinal vesicle (GV)- and metaphase II (MII)-stage oocytes, zygotes, 2-, 4-, and 8-cell-stage embryos, morulas, and blastocysts were produced in vitro and their gene expression was analyzed. The results revealed that the coding sequence of porcine PTTG1 is 609-bp in length and that it encodes a 202-aa polypeptide. Using qRT-PCR, PTTG1 mRNA expression was observed to be maintained at high levels in GV- and MII-stage oocytes. The transcript levels in oocytes were also significantly higher than those in embryos from the zygote to blastocyst stages. Immunohistochemical analyses revealed that porcine PTTG1 was primarily localized to the cytoplasm and partially localized to the nucleus. Furthermore, the PTTG1 protein levels in MII-stage oocytes and zygotes were significantly higher than those in embryos from the 2-cell to blastocyst stage. After fertilization, the level of this protein began to decrease gradually until the blastocyst stage. The results of our study suggest that porcine PTTG1 is a new candidate maternal effect gene (MEG) that may participate in the processes of oocyte maturation and zygotic genome activation during porcine embryogenesis. PMID:27058238

  4. Primary, non-exophytic, optic nerve germ cell tumors.

    PubMed

    DiLuna, Michael L; Two, Aimee M; Levy, Gillian H; Patel, Toral; Huttner, Anita J; Duncan, Charles C; Piepmeier, Joseph M

    2009-12-01

    Tumors of the optic chiasm are relatively uncommon and usually associated with phakomatoses such as neurofibromatosis. Even more rare is the presentation of a primary, non-exophytic, isolated optic chiasm germ cell tumor (GCT). These tumors have imaging characteristics nearly indistinguishable from optic chiasmatic gliomas (OCGs). Herein we describe two cases of young men who presented with similar findings of progressive, painless visual loss and hypothalamic-pituitary-adrenal axis dysfunction including diabetes insipidus. Brain imaging was non-diagnostic and suggestive of an OCG. Pathology demonstrated GCTs in each case highlighting the importance of biopsy confirmation of the diagnosis. Both patients underwent a pterional craniotomy and sub-frontal approach to the optic chiasm. The chiasm was diffusely enlarged and discolored in each case without evidence of sellar, suprasellar or perichiasmatic pathology. Pathology demonstrated a malignant mixed GCT in the first patient and a germinoma in the second. This case series highlights the importance of tissue biopsy for patients with progressive symptoms from optic chiasm tumors. Furthermore, this is the first report of a primary, non-exophytic malignant mixed GCT. As the treatment regimens differ widely between optic chiasm GCTs and chiasm gliomas, tissue diagnosis is important. PMID:19554263

  5. Treatment Option Overview (Extragonadal Germ Cell Tumors)

    MedlinePlus

    ... hCG and LDH may be at any level. Poor prognosis A nonseminoma extragonadal germ cell tumor is in the poor prognosis group if: the tumor is in the ... extragonadal germ cell tumor does not have a poor prognosis group. Treatment Option Overview Key Points There ...

  6. Impact of environmental chemicals on the thyroid hormone function in pituitary rat GH3 cells.

    PubMed

    Ghisari, Mandana; Bonefeld-Jorgensen, Eva C

    2005-12-01

    Endocrine disrupting chemicals (EDCs) are widespread in the environment and suspected to interfere with the function of thyroid hormones (THs). We investigated the TH disrupting activity of different classes of EDCs including plasticizers (bisphenol A, bisphenol A dimethacrylate), alkylphenols (4-n-nonylphenol, 4-octylphenol), pesticides (prochloraz, iprodion, chlorpyrifos), PCB metabolites (OH-PCB 106, OH-PCB 121, OH-PCB 69) and brominated flame-retardants (tetrabromobisphenol A). The ED potential of a chemical was determined by its effect on the cell proliferation of TH-dependent rat pituitary GH3 cell line. All tested chemicals significantly interfered with the cell proliferation alone or upon co-treatment with T3. The growth of GH3 cells was stimulated by all tested chemicals, but 4-n-nonylphenol, 4-octylphenol, prochloraz and iprodion elicited an inhibitory effect on cell growth. In conclusion, these EDCs have the potential to exert TH disruption increasing the risk or a negative impact on fetal brain development, resulting in cognitive dysfunctions. PMID:16221524

  7. Lactotrophs: the new and major source for VEGF secretion and the influence of ECM on rat pituitary function in vitro.

    PubMed

    Alfer, Joachim; Neulen, Joseph; Gaumann, Andreas

    2015-05-01

    Vascular endothelial growth factor (VEGF) plays a pivotal role in pituitary endocrine function by influencing fenestration and blood vessel growth. Folliculostellate (FS) cells, which represent only a small number of pituitary cells, are recognized to produce VEGF. Tissue sections and primary pituitary cell cultures from rat pituitary glands were performed to co-localize VEGF and pituitary lactotrophs, which represents nearly 50% of all pituitary cells, by immunofluorescence. VEGF is co-localized with prolactin-producing cells in vivo and in vitro. FS cells are present infrequently in vivo (1.6%) and in vitro (2.4%). Culture supernatants were analyzed for the presence of VEGF by ELISA. VEGF levels are always significantly lower in supernatants from the cells that are seeded on Matrigel extracellular matrix (ECM) compared to the cells grown on plastic. Lower VEGF concentrations in supernatants from the pituitary cells cultured on ECM may reflect a more adequate cell environment compared to culture on plastic. These results demonstrate for the first time, that VEGF is expressed by lactotrophs, which outnumber FS cells. These results are of potential clinical relevance especially in oncology for the interpretation of studies investigating anti‑angiogenic treatment of pituitary tumors. PMID:25778675

  8. Role of nonselective cation channels in spontaneous and protein kinase A-stimulated calcium signaling in pituitary cells.

    PubMed

    Tomić, Melanija; Kucka, Marek; Kretschmannova, Karla; Li, Shuo; Nesterova, Maria; Stratakis, Constantine A; Stojilkovic, Stanko S

    2011-08-01

    Several receptors linked to the adenylyl cyclase signaling pathway stimulate electrical activity and calcium influx in endocrine pituitary cells, and a role for an unidentified sodium-conducting channel in this process has been proposed. Here we show that forskolin dose-dependently increases cAMP production and facilitates calcium influx in about 30% of rat and mouse pituitary cells at its maximal concentration. The stimulatory effect of forskolin on calcium influx was lost in cells with inhibited PKA (cAMP-dependent protein kinase) and in cells that were haploinsufficient for the main PKA regulatory subunit but was preserved in cells that were also haploinsufficient for the main PKA catalytic subunit. Spontaneous and forskolin-stimulated calcium influx was present in cells with inhibited voltage-gated sodium and hyperpolarization-activated cation channels but not in cells bathed in medium, in which sodium was replaced with organic cations. Consistent with the role of sodium-conducting nonselective cation channels in PKA-stimulated Ca(2+) influx, cAMP induced a slowly developing current with a reversal potential of about 0 mV. Two TRP (transient receptor potential) channel blockers, SKF96365 and 2-APB, as well as flufenamic acid, an inhibitor of nonselective cation channels, also inhibited spontaneous and forskolin-stimulated electrical activity and calcium influx. Quantitative RT-PCR analysis indicated the expression of mRNA transcripts for TRPC1 > TRPC6 > TRPC4 > TRPC5 > TRPC3 in rat pituitary cells. These experiments suggest that in pituitary cells constitutively active cation channels are stimulated further by PKA and contribute to calcium signaling indirectly by controlling the pacemaking depolarization in a sodium-dependent manner and directly by conducting calcium. PMID:21586701

  9. Interaction of tumor cells with the microenvironment

    PubMed Central

    2011-01-01

    Recent advances in tumor biology have revealed that a detailed analysis of the complex interactions of tumor cells with their adjacent microenvironment (tumor stroma) is mandatory in order to understand the various mechanisms involved in tumor growth and the development of metastasis. The mutual interactions between tumor cells and cellular and non-cellular components (extracellular matrix = ECM) of the tumor microenvironment will eventually lead to a loss of tissue homeostasis and promote tumor development and progression. Thus, interactions of genetically altered tumor cells and the ECM on the one hand and reactive non-neoplastic cells on the other hand essentially control most aspects of tumorigenesis such as epithelial-mesenchymal-transition (EMT), migration, invasion (i.e. migration through connective tissue), metastasis formation, neovascularisation, apoptosis and chemotherapeutic drug resistance. In this mini-review we will focus on these issues that were recently raised by two review articles in CCS. PMID:21914164

  10. Determination of cell proliferation using Mcm2 antigen and evaluation of apoptosis and TGF-beta1 expression in GH-secreting or clinically nonfunctioning pituitary adenomas.

    PubMed

    Dallago, Cristina Micheletto; Barbosa-Coutinho, Ligia Maria; Ferreira, Nelson Pires; Meurer, Rosalva; Pereira-Lima, Julia Fernanda Semmelmann; Oliveira, Miriam da Costa

    2010-03-01

    Pituitary adenomas (PA) occasionally show aggressive behavior, with invasion of the surrounding tissues. The identification of markers able to recognize aggressive PA in early stages remains a challenge. We aimed to determine the expression of a new cell proliferation marker, Mcm2, and the presence of apoptosis in PA, and to evaluate the association of clinicopathological features with the apoptotic and proliferative indices. Additionally, the TGF-beta1 expression, an inducer of apoptosis, was determined. The proliferative index was determined in GH-secreting or clinically nonfunctioning PA using immunohistochemical (IH) methods for Mcm2 and Ki-67 antigens. The apoptosis was assessed by the TUNEL method and the TGF-beta1 expression by IH. A significant positive correlation was found between log Mcm2 index and log Ki-67 index (p < 0.001). Mcm2 and Ki-67 detected a similar number of proliferating cells. Mcm2 index showed a significant association with tumor extension (p = 0.02), but not with tumor invasion. Apoptosis was detected in 17% of the adenomas, with a maximum apoptotic index of 0.77%. Immunoreactivity to TGF-beta1 was observed in 77% of the adenomas, showing an association with tumor extension. We concluded that, in this sample, Mcm2 was similar to Ki-67 in the identification of the proliferating cells and that apoptosis was rare. PMID:20174894

  11. Measurements of prolactin and growth hormone synthesis and secretion by rat pituitary cells in culture.

    PubMed

    Gautvik, K M; Kriz, M

    1976-02-01

    A specific and sensitive immunoprecipitation method for measurements of biosynthesized radioactive prolactin and growth hormone is described. Antisera to rat prolactin and growth hormone were developed in the rabbit and monkey, respectively. The specificity of the immune sera was assessed by polyacylamide gel electrophoresis of the dissolved immunoprecipitates. The two antisera showed cross-reactions with the nonhomologous hormone of less than 1%. Separation of tritium-labelled prolactin and growth hormone by immunoprecipitation, followed by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate was shown to be 95-57% complete. When both hormones were measured in the same microsample by sequential immunoprecipitation, the reaction was 97% complete for determination of intra- and extracellular prolactin and extracellular growth hormone, but 85% complete for determination of intracellular growth hormone. This method has been used to characterize the basal synthesis and secretion of prolactin and growth hormone in three different but related, pituitary cell strains. Radioactive prolactin and growth hormone was obtained from monolayer cultures when the cells were grown in the presence of [3H]L-leucine. The rate of prolactin synthesis and extracellular accumulation was higher than that of growth hormone in a cell strain which produced both hormones. In these cells prolactin synthesis represents 1-5%, and growth hormone 0.1-0.6% of total protein synthesis. PMID:942913

  12. Receptor-mediated binding and uptake of GnRH agonist and antagonist by pituitary cells

    SciTech Connect

    Jennes, L.; Stumpf, W.E.; Conn, P.M.

    1984-01-01

    The intracellular pathway of an enzyme resistant GnRH agonist (D- Lys6 -GnRH) conjugated to ferritin or to colloidal gold was followed in cultured pituitary cells. After an initial uniform distribution over the cell surface of gonadotropes, the electrondense marker was internalized, either individually or in small groups. After longer incubation times, the marker appeared in the lysosomal compartment and the Golgi apparatus, where it could be found in the vesicular as well as cisternal portion. In addition, the receptor-mediated endocytosis of the GnRH antagonist D-p-Glu1-D-Phe2-D-Trp3-D- Lys6 -GnRH was studied by light and electron microscopic autoradiography after 30 and 60 min of incubation to ensure uptake. At both time points, in in vitro as well as in vivo studies, silver grains were localized over cytoplasmic organelles of castration cells, including dilated endoplasmic reticulum, lysosomes, and clear vesicles. No consistent association with cell nuclei, mitochondria, or secretory vesicles could be observed. The results suggest that both agonist and antagonist are binding selectively to the plasma membrane of gonadotropes and subsequently are taken up via receptor-mediated endocytosis for degradation or possible action on synthetic processes.

  13. G-protein-coupled glucocorticoid receptors on the pituitary cell membrane.

    PubMed

    Maier, Christina; Rünzler, Dominik; Schindelar, Julia; Grabner, Gottfried; Waldhäusl, Werner; Köhler, Gottfried; Luger, Anton

    2005-08-01

    Rapid, nongenomic actions of glucocorticoids (GCs) have been well documented, but information about putative membrane receptors that mediate them is scarce. We used fluorescence correlation spectroscopy to search for membrane GC-binding on the mouse pituitary cell line AtT-20. A slowly diffusing fraction (tau3; diffusion constant 3x10(-10) cm2 s-1) of fluorescein-labeled dexamethasone on the cell membrane corresponds to fluorescein-dexamethasone binding. Preincubation experiments were performed to test binding specificity: a 500-fold excess of unlabeled dexamethasone abolished subsequent fluorescein-dexamethasone membrane binding from 58+/-2 (control) to 8+/-1 (% of tau3, mean+/-s.e.m.), the natural ligand corticosterone prevented it partially (29+/-2), while the sex steroids estradiol (56+/-4) and progesterone (50+/-4) and the GC-receptor antagonist RU486 (56+/-2) had no effect. Preincubation with pertussis toxin resulted in disappearance of the slowest diffusion component (11+/-4) suggesting association of the receptor with a G-protein. Varying the concentration of fluorescein-dexamethasone showed that membrane binding is highly cooperative with an apparent Kd of 180 nM and Bmax of 230 nM. Taken together, these results demonstrate high-affinity GC-binding on the cell membrane of AtT-20 cells with characteristics distinct from intracellular binding. PMID:16079279

  14. Granular Cell Tumor: An Uncommon Benign Neoplasm

    PubMed Central

    Gayen, Tirthankar; Das, Anupam; Shome, Kaushik; Bandyopadhyay, Debabrata; Das, Dipti; Saha, Abanti

    2015-01-01

    Granular cell tumor is a distinctly rare neoplasm of neural sheath origin. It mainly presents as a solitary asymptomatic swelling in the oral cavity, skin, and rarely internal organs in the middle age. Histopathology is characteristic, showing polyhedral cells containing numerous fine eosinophilic granules with indistinct cell margins. We present a case of granular cell tumor on the back of a 48-year-old woman which was painful, mimicking an adnexal tumor. PMID:26120181

  15. Immunocytochemical and ultrastructural identification of pituitary cell types in the protogynous Thalassoma duperrey during adult sexual ontogeny

    USGS Publications Warehouse

    Parhar, I.S.; Nagahama, Y.; Grau, E.G.; Ross, R.M.

    1998-01-01

    Protogynous wrasses (Thalassoma duperrey): females (F), primary males (PM) along with a few terminal-phase males (TM) and sex-changed males (SM), were used to characterize the topographical organization of the pituitary. In general, immunocytochemical and ultrastructural features of the adenohypophyseal cell types of the saddleback wrasse pituitary resemble those of other teleosts. In the rostral pars distalis (RPD), corticotropic cells were found bordering the neurohypophysis (NH) and surrounding the centroventrally located prolactin cells. Thyrotropic cells formed a small group in the anteriodorsal part of the rostral and proximal pars distalis (PPD). The somatotropic cells were distributed in large clusters, mostly organized in cell cords around the interdigitations of the NH of the dorsal PPD. Cells containing gonadotropin I?? subunit were localized in the dorsal parts of the PPD, in close association with somatotropic cells and gonadotropin II?? subunit containing cells were seen in the centroventral parts of the PPD and along the periphery of the pars intermedia (PI). The pars intermedia was composed of melanotropic cells and somatolactin cells that lined the neurohypohysis. Distinct ultrastructural differences in corticotropic and somatotropic cells were not observed between the four groups. In all groups, prolactin cells in the ventral-most RPD could be immature cells or actively secreting prolactin. Gonadotropic II cells of PM and F had relatively higher incidence of "nuclear budding" and cell organelles compared to TM and SM. Besides gonadotropic, the active melanotropic and somatolactin cells might be associated with some aspect(s) of reproduction.

  16. Cell-specific distributions of estrogen receptor alpha (ERα) and androgen receptor (AR) in anterior pituitary glands from adult cockerels as revealed by immunohistochemistry.

    PubMed

    Sun, Dehao; Cui, Tongtong; Luo, Haoshu; Li, Ruiguo; Cui, Sheng; Liu, Jiali

    2012-06-01

    Estrogens and androgens play important roles in regulating the hormone-secreting functions of the pituitary gland by binding to their corresponding receptors. However, the expression of estrogen receptors (ERs) and the androgen receptor (AR) and the cell types containing ERs and AR in the anterior pituitary gland of adult chickens have not been well-studied. In this study, the distribution of ERα, AR and their corresponding cell types in the anterior pituitary gland of adult cockerels was detected by immunohistochemistry. The results showed that ERα was expressed in 68.63 % of luteinizing hormone (LH) producing cells but was not found in thyrotropes, lactotropes, somatotropes, corticotropes and folliculo-stellate (FS) cells. Pituitary hormone and AR double labeling results showed that about 37 % of LH cells and 50 % of thyroid-stimulating hormone (TSH) producing cells expressed AR, respectively. In contrast, less than 1 % of the somatotropes had an AR positive signal and AR signals were not detected in lactotropes, corticotropes or FS cells. In addition, there were only a few AR and ERα dual-labeled cells observed. These novel results provide evidence for a cell-specific distribution of ERα and AR in the anterior pituitary from adult cockerels by immunohistochemistry. The different distributions of ERα and AR in the LH cells suggest that the feedback-regulating mechanisms of estrogen and androgen on the pituitary hormones secretion are different. The functions and related mechanisms still need to be elucidated further. PMID:22453555

  17. Pituitary: Secretory Tumors

    MedlinePlus

    ... too much prolactin, the hormone that causes milk production. Prolactinomas affect both men and women. While excess ... acting somatostatin analogue, a drug that suppresses GH production. Somatostatin analogues are given by a monthly injection ...

  18. Pituitary Tumors Fact Sheet

    MedlinePlus

    ... y Cuidadores Hormones and Health Journey Through the Endocrine System Endocrine Disrupting Chemicals (EDCs) Endocrine Glands and Types ... Women's Health Hormones and Health Journey Through the Endocrine System Endocrine Disrupting Chemicals (EDCs) Endocrine Glands and Types ...

  19. Endogenous retinoid X receptors can function as hormone receptors in pituitary cells.

    PubMed Central

    Davis, K D; Berrodin, T J; Stelmach, J E; Winkler, J D; Lazar, M A

    1994-01-01

    Retinoids regulate gene transcription by interacting with both retinoic acid (RA) receptors (RARs) and retinoid X receptors (RXRs). Since unliganded RXRs can act as heterodimerization partners for RARs and other nuclear hormone receptors, it is unclear whether ligand binding by RXRs actually regulates the expression of naturally occurring genes. To address this issue, we synthesized the RXR-selective retinoid SR11237 and confirmed its specificity in transient transfection and proteolytic susceptibility assays before using it to assess the contribution of ligand-activated RXRs to retinoid action. Unlike RAR ligands, SR11237 did not increase endogenous RAR beta mRNA levels in F9 embryonal carcinoma cells, even though it activated transcription of an RXR-responsive reporter gene in these cells. Thus, it is likely that RARs mediate the induction of RAR beta gene expression by RA. In contrast, the RXR-specific ligand induced rat growth hormone mRNA in GH3 pituitary cells, indicating that the effects of RA on growth hormone gene expression at least in part involve ligand binding to endogenous RXRs in vivo. Our results indicate that in addition to serving as cofactors for other nuclear hormone receptors, endogenous RXRs can function as ligand-dependent regulators of gene expression, i.e., classical nuclear hormone receptors. Images PMID:7935425

  20. Hypothalamus-Pituitary-Adrenal cell-mediated immunity regulation in the Immune Restoration Inflammatory Syndrome

    PubMed Central

    Khakshooy, Allen; Chiappelli, Francesco

    2016-01-01

    Over one third of the patients sero-positive for the human immunodeficiency virus (HIV) with signs of the acquired immune deficiency syndrome (AIDS), and under treatment with anti-retroviral therapy (ART), develop the immune reconstitution inflammatory syndrome (IRIS). It is not clear what variables are that determine whether a patient with HIV/AIDS will develop ART-related IRIS, but the best evidence base thus far indicates that HIV/AIDS patients with low CD4 cell count, and HIV/AIDS patients whose CD4 count recovery shows a sharp slope, suggesting a particularly fast "immune reconstitution", are at greater risk of developing IRIS. Here, we propose the hypothesis that one important variable that can contribute to low CD4 cell count number and function in ART-treated HIV/AIDS patients is altered hypothalamic-pituitary-adrenal (HPA) cell-mediated immune (CMI) regulation. We discuss HPA-CMI deregulation in IRIS as the new frontier in comparative effectiveness research (CRE) for obtaining and utilizing the best evidence base for treatment of patients with HIV/AIDS in specific clinical settings. We propose that our hypothesis about altered HPA-CMI may extend to the pathologies observed in related viral infection, including Zika PMID:27212842

  1. Hypothalamus-Pituitary-Adrenal cell-mediated immunity regulation in the Immune Restoration Inflammatory Syndrome.

    PubMed

    Khakshooy, Allen; Chiappelli, Francesco

    2016-01-01

    Over one third of the patients sero-positive for the human immunodeficiency virus (HIV) with signs of the acquired immune deficiency syndrome (AIDS), and under treatment with anti-retroviral therapy (ART), develop the immune reconstitution inflammatory syndrome (IRIS). It is not clear what variables are that determine whether a patient with HIV/AIDS will develop ART-related IRIS, but the best evidence base thus far indicates that HIV/AIDS patients with low CD4 cell count, and HIV/AIDS patients whose CD4 count recovery shows a sharp slope, suggesting a particularly fast "immune reconstitution", are at greater risk of developing IRIS. Here, we propose the hypothesis that one important variable that can contribute to low CD4 cell count number and function in ART-treated HIV/AIDS patients is altered hypothalamic-pituitary-adrenal (HPA) cell-mediated immune (CMI) regulation. We discuss HPA-CMI deregulation in IRIS as the new frontier in comparative effectiveness research (CRE) for obtaining and utilizing the best evidence base for treatment of patients with HIV/AIDS in specific clinical settings. We propose that our hypothesis about altered HPA-CMI may extend to the pathologies observed in related viral infection, including Zika. PMID:27212842

  2. Novel evidence that pituitary gonadotropins directly stimulate human leukemic cells-studies of myeloid cell lines and primary patient AML and CML cells

    PubMed Central

    Abdelbaset-Ismail, Ahmed; Borkowska, Sylwia; Janowska-Wieczorek, Anna; Tonn, Torsten; Rodriguez, Cesar; Moniuszko, Marcin; Bolkun, Lukasz; Koloczko, Janusz; Eljaszewicz, Andrzej; Ratajczak, Janina; Ratajczak, Mariusz Z.; Kucia, Magda

    2016-01-01

    We recently reported that normal hematopoietic stem cells express functional pituitary sex hormone (SexH) receptors. Here we report for the first time that pituitary-secreted gonadotrophins stimulate migration, adhesion, and proliferation of several human myeloid and lymphoid leukemia cell lines. Similar effects were observed after stimulation of human leukemic cell lines by gonadal SexHs. This effect seems to be direct, as the SexH receptors expressed by leukemic cells responded to stimulation by phosphorylation of MAPKp42/44 and AKTser473. Furthermore, in parallel studies we confirmed that human primary patient-derived AML and CML blasts also express several functional SexH receptors. These results shed more light on the potential role of SexHs in leukemogenesis and, in addition, provide further evidence suggesting a developmental link between hematopoiesis and the germline. PMID:26701888

  3. Novel evidence that pituitary gonadotropins directly stimulate human leukemic cells-studies of myeloid cell lines and primary patient AML and CML cells.

    PubMed

    Abdelbaset-Ismail, Ahmed; Borkowska, Sylwia; Janowska-Wieczorek, Anna; Tonn, Torsten; Rodriguez, Cesar; Moniuszko, Marcin; Bolkun, Lukasz; Koloczko, Janusz; Eljaszewicz, Andrzej; Ratajczak, Janina; Ratajczak, Mariusz Z; Kucia, Magda

    2016-01-19

    We recently reported that normal hematopoietic stem cells express functional pituitary sex hormone (SexH) receptors. Here we report for the first time that pituitary-secreted gonadotrophins stimulate migration, adhesion, and proliferation of several human myeloid and lymphoid leukemia cell lines. Similar effects were observed after stimulation of human leukemic cell lines by gonadal SexHs. This effect seems to be direct, as the SexH receptors expressed by leukemic cells responded to stimulation by phosphorylation of MAPKp42/44 and AKTser473. Furthermore, in parallel studies we confirmed that human primary patient-derived AML and CML blasts also express several functional SexH receptors. These results shed more light on the potential role of SexHs in leukemogenesis and, in addition, provide further evidence suggesting a developmental link between hematopoiesis and the germline. PMID:26701888

  4. Tumor initiating cells in malignant gliomas

    PubMed Central

    Hadjipanayis, Costas G.; Van Meir, Erwin G.

    2009-01-01

    A rare subpopulation of cells within malignant gliomas, which shares canonical properties with neural stem cells (NSCs), may be integral to glial tumor development and perpetuation. These cells, also known as tumor initiating cells (TICs), have the ability to self-renew, develop into any cell in the overall tumor population (multipotency), and proliferate. A defining property of TICs is their ability to initiate new tumors in immunocompromised mice with high efficiency. Mounting evidence suggests that TICs originate from the transformation of NSCs and their progenitors. New findings show that TICs may be more resistant to chemotherapy and radiation than the bulk of tumor cells, thereby permitting recurrent tumor formation and accounting for the failure of conventional therapies. The development of new therapeutic strategies selectively targeting TICs while sparing NSCs may provide for more effective treatment of malignant gliomas. PMID:19189072

  5. MEN1 tumorigenesis in the pituitary and pancreatic islet requires Cdk4 but not Cdk2.

    PubMed

    Gillam, M P; Nimbalkar, D; Sun, L; Christov, K; Ray, D; Kaldis, P; Liu, X; Kiyokawa, H

    2015-02-12

    Recent studies suggest that physiological and tumorigenic proliferation of mammalian cells is controlled by multiple cyclin-dependent kinases (CDKs) largely in tissue-specific manners. We and others previously demonstrated that adult mice deficient for the Cyclin D partner CDK4 (Cdk4(-/-) mice) exhibit hypoplasia in the pituitary and pancreatic islet due to primary postnatal defects in proliferation. Intriguingly, those neuroendocrine tissues affected in Cdk4(-/-) mice are the primary targets of tumorigenesis in the syndrome of multiple endocrine neoplasia type-1 (MEN1). Mice with heterozygous disruption of the tumor suppressor Men1 gene (Men1(+/-)) develop tumors in the pituitary, pancreatic islets and other neuroendocrine tissues, which is analogous to humans with MEN1 mutations. To explore the genetic interactions between loss of Men1 and activation of CDKs, we examined the impact of Cdk4 or Cdk2 disruption on tumorigenesis in Men1(+/-) mice. A majority of Men1(+/-) mice with wild-type CDKs developed pituitary and islet tumors by 15 months of age. Strikingly, Men1(+/-); Cdk4(-/-) mice did not develop any tumors, and their islets and pituitaries remained hypoplastic with decreased proliferation. In contrast, Men1(+/-); Cdk2(-/-) mice showed pituitary and islet tumorigenesis comparable to those in Men1(+/-) mice. Pituitaries of Men1(+/-); Cdk4(-/-) mice showed no signs of loss of heterozygosity (LOH) in the Men1 locus, whereas tumors in Men1(+/-) mice and Men1(+/-); Cdk2(-/-) mice exhibited LOH. Consistently, CDK4 knockdown in INS-1 insulinoma cells inhibited glucose-stimulated cell cycle progression with a significant decrease in phosphorylation of retinoblastoma protein (RB) at specific sites including Ser780. CDK2 knockdown had minimum effects on RB phosphorylation and cell cycle progression. These data suggest that CDK4 is a critical downstream target of MEN1-dependent tumor suppression and is required for tumorigenic proliferation in the pituitary and

  6. Effects of spaceflight on rat pituitary cell function: Preflight and flight experiment for pituitary gland study on COSMOS, 1989

    NASA Technical Reports Server (NTRS)

    Hymer, Wesley C.

    1990-01-01

    The secretory capacity of growth hormone (GH) and prolactin (PRL) cells prepared from rats flown in space on the 12.5 day mission of Cosmos 1887 and the 14 day mission of Cosmos 2044 was evaluated in several post-flight tests on Earth. The results showed statistically significant and repeatable decrements in hormone release, especially when biological assays (rather than immunological assays) were used in the tests. Significant and repeatable intracellular changes in GH cells from the flight animals were also found; most important were increases in the GH-specific cytoplasmic staining intensities and cytoplasmic areas occupied by hormore. Tail suspension of rats for 14 days, an established model for mimicking musculo-skeletal changes seen in spaceflown rats, results in some changes in GH and PRL cell function that were similar to those from spaceflown animals. Our results add to a growing body of data that described deconditioning of physiological systems in spaceflight and provide insights into the time frame that might be required for readaptation of the GH/PRL cell system upon return to Earth.

  7. Cell Fusion Connects Oncogenesis with Tumor Evolution

    PubMed Central

    Zhou, Xiaofeng; Merchak, Kevin; Lee, Woojin; Grande, Joseph P.; Cascalho, Marilia; Platt, Jeffrey L.

    2016-01-01

    Cell fusion likely drives tumor evolution by undermining chromosomal and DNA stability and/or by generating phenotypic diversity; however, whether a cell fusion event can initiate malignancy and direct tumor evolution is unknown. We report that a fusion event involving normal, nontransformed, cytogenetically stable epithelial cells can initiate chromosomal instability, DNA damage, cell transformation, and malignancy. Clonal analysis of fused cells reveals that the karyotypic and phenotypic potential of tumors formed by cell fusion is established immediately or within a few cell divisions after the fusion event, without further ongoing genetic and phenotypic plasticity, and that subsequent evolution of such tumors reflects selection from the initial diverse population rather than ongoing plasticity of the progeny. Thus, one cell fusion event can both initiate malignancy and fuel evolution of the tumor that ensues. PMID:26066710

  8. In1-ghrelin splicing variant is overexpressed in pituitary adenomas and increases their aggressive features

    PubMed Central

    Ibáñez-Costa, Alejandro; Gahete, Manuel D.; Rivero-Cortés, Esther; Rincón-Fernández, David; Nelson, Richard; Beltrán, Manuel; de la Riva, Andrés; Japón, Miguel A.; Venegas-Moreno, Eva; Gálvez, Ma Ángeles; García-Arnés, Juan A.; Soto-Moreno, Alfonso; Morgan, Jennifer; Tsomaia, Natia; Culler, Michael D.; Dieguez, Carlos; Castaño, Justo P.; Luque, Raúl M.

    2015-01-01

    Pituitary adenomas comprise a heterogeneous subset of pathologies causing serious comorbidities, which would benefit from identification of novel, common molecular/cellular biomarkers and therapeutic targets. The ghrelin system has been linked to development of certain endocrine-related cancers. Systematic analysis of the presence and functional implications of some components of the ghrelin system, including native ghrelin, receptors and the recently discovered splicing variant In1-ghrelin, in human normal pituitaries (n = 11) and pituitary adenomas (n = 169) revealed that expression pattern of ghrelin system suffers a clear alteration in pituitary adenomasas comparedwith normal pituitary, where In1-ghrelin is markedly overexpressed. Interestingly, in cultured pituitary adenoma cells In1-ghrelin treatment (acylated peptides at 100 nM; 24–72 h) increased GH and ACTH secretion, Ca2+ and ERK1/2 signaling and cell viability, whereas In1-ghrelin silencing (using a specific siRNA; 100 nM) reduced cell viability. These results indicate that an alteration of the ghrelin system, specially its In1-ghrelin variant, could contribute to pathogenesis of different pituitary adenomas types, and suggest that this variant and its related ghrelin system could provide new tools to identify novel, more general diagnostic, prognostic and potential therapeutic targets in pituitary tumors. PMID:25737012

  9. In1-ghrelin splicing variant is overexpressed in pituitary adenomas and increases their aggressive features.

    PubMed

    Ibáñez-Costa, Alejandro; Gahete, Manuel D; Rivero-Cortés, Esther; Rincón-Fernández, David; Nelson, Richard; Beltrán, Manuel; de la Riva, Andrés; Japón, Miguel A; Venegas-Moreno, Eva; Gálvez, Ma Ángeles; García-Arnés, Juan A; Soto-Moreno, Alfonso; Morgan, Jennifer; Tsomaia, Natia; Culler, Michael D; Dieguez, Carlos; Castaño, Justo P; Luque, Raúl M

    2015-01-01

    Pituitary adenomas comprise a heterogeneous subset of pathologies causing serious comorbidities, which would benefit from identification of novel, common molecular/cellular biomarkers and therapeutic targets. The ghrelin system has been linked to development of certain endocrine-related cancers. Systematic analysis of the presence and functional implications of some components of the ghrelin system, including native ghrelin, receptors and the recently discovered splicing variant In1-ghrelin, in human normal pituitaries (n = 11) and pituitary adenomas (n = 169) revealed that expression pattern of ghrelin system suffers a clear alteration in pituitary adenomasas compared with normal pituitary, where In1-ghrelin is markedly overexpressed. Interestingly, in cultured pituitary adenoma cells In1-ghrelin treatment (acylated peptides at 100 nM; 24-72 h) increased GH and ACTH secretion, Ca(2+) and ERK1/2 signaling and cell viability, whereas In1-ghrelin silencing (using a specific siRNA; 100 nM) reduced cell viability. These results indicate that an alteration of the ghrelin system, specially its In1-ghrelin variant, could contribute to pathogenesis of different pituitary adenomas types, and suggest that this variant and its related ghrelin system could provide new tools to identify novel, more general diagnostic, prognostic and potential therapeutic targets in pituitary tumors. PMID:25737012

  10. Short- and long-term exposure to alternating magnetic field (50 Hz, 0.5 mT) affects rat pituitary ACTH cells: Stereological study.

    PubMed

    Rauš Balind, Snežana; Manojlović-Stojanoski, Milica; Milošević, Verica; Todorović, Dajana; Nikolić, Ljiljana; Petković, Branka

    2016-04-01

    The aim of the present study was to determine does extremely low frequency magnetic field (ELF-MF, 50 Hz, 0.5 mT) affect pituitary adrenocorticotroph (ACTH) cells in adult animals. We performed two series of experiments: (1) short-term exposure of 3-month-old rats to ELF-MF for 1 and 7 days, and (2) long-term exposure of rats to ELF-MF from their conception to 3 months of age. Stereological study was performed on immunolabeled pituitary ACTH cells. The total number and volume of ACTH cells, the volume of their nuclei and pituitary volume were measured. ELF-MF exposure for 1 day significantly decreased total number and volume of ACTH cells, the volume of their nuclei, as well as pituitary volume. ELF-MF exposure for 7 days significantly reduced only the volume of ACTH cells. Life-long exposure to ELF-MF induced decrease in the volume of ACTH cells and pituitary volume. We can conclude that the applied ELF-MF has a strong influence on morphometrical parameters of the pituitary ACTH cells and could be considered as a stressogenic factor. PMID:25346405