Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
1.
Cell Mol Neurobiol ; 44(1): 31, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557942

RESUMO

Glioblastoma multiforme (GBM) is the most predominant and malignant primary brain tumor in adults. Thymic stromal lymphopoietin (TSLP), a cytokine primarily generated by activated epithelial cells, has recently garnered attention in cancer research. This study was aimed to elucidate the significance of TSLP in GBM cells and its interplay with the immune system, particularly focused on granulocyte neutrophils. Our results demonstrate that the tumor produces TSLP when stimulated with epidermal growth factor (EGF) in both the U251 cell line and the GBM biopsy (GBM-b). The relevance of the TSLP function was evaluated using a 3D spheroid model. Spheroids exhibited increased diameter, volume, and proliferation. In addition, TSLP promoted the generation of satellites surrounding the main spheroids and inhibited apoptosis in U251 treated with temozolomide (TMZ). Additionally, the co-culture of polymorphonuclear (PMN) cells from healthy donors with the U251 cell line in the presence of TSLP showed a reduction in apoptosis and an increase in IL-8 production. TSLP directly inhibited apoptosis in PMN from GBM patients (PMN-p). Interestingly, the vascular endothelial growth factor (VEGF) production was elevated in PMN-p compared with PMN from healthy donors. Under these conditions, TSLP also increased VEGF production, in PMN from healthy donors. Moreover, TSLP upregulated programed death-ligand 1 (PDL-1) expression in PMN cultured with U251. On the other hand, according to our results, the analysis of RNA-seq datasets from Illumina HiSeq 2000 sequencing platform performed with TIMER2.0 webserver demonstrated that the combination of TSLP with neutrophils decreases the survival of the patient. In conclusion, our results position TSLP as a possible new growth factor in GBM and indicate its modulation of the tumor microenvironment, particularly through its interaction with PMN.


Assuntos
Glioblastoma , Linfopoietina do Estroma do Timo , Adulto , Humanos , Células Cultivadas , Citocinas/metabolismo , Neutrófilos/metabolismo , Microambiente Tumoral , Fator A de Crescimento do Endotélio Vascular
3.
Front Endocrinol (Lausanne) ; 13: 870172, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35928898

RESUMO

Clinically silent corticotroph tumors are usually macroadenomas that comprise 20% of ACTH tumors. They frequently progress to aggressive tumors with high recurrence, invasiveness, and on rare occasions, they may become hormonally active causing Cushing's disease. Trustable biomarkers that can predict their aggressive course, as well as their response to traditional or new therapies, are paramount. Aberrant ß-Catenin expression and localization have been proposed as responsible for several malignancies including pituitary tumors. Nevertheless, the role of ß-Catenin in the aggressive transformation of silent corticotropinomas and their response to Temozolomide salvage treatment have not been explored yet. In this work, we present a case of a silent corticotroph tumor that invaded cavernous sinus and compressed optic chiasm and, after a first total resection and tumor remission it recurred six years later as an aggressive ACTH-secreting tumor. This lesion grew with carotid compromise and caused Cushing's signs. It required multiple medical treatments including Cabergoline, Ketoconazole, TMZ, and radiotherapy. Besides, other two surgeries were needed until it could be controlled. Interestingly, we found α-SMA vascular area reduction and differential ß-Catenin cell localization in the more aggressive tumor stages characterized by high Ki-67 indexes and p53 expression. Our results may indicate a role of angiogenesis and ß-Catenin trigged events in the pituitary tumor progression, which could in turn affect the response to TMZ and/or conventional treatments. These molecular findings in this unusual case could be useful for future management of aggressive pituitary tumors.


Assuntos
Adenoma , Neoplasias Hipofisárias , Adenoma/patologia , Hormônio Adrenocorticotrópico/metabolismo , Corticotrofos/metabolismo , Corticotrofos/patologia , Humanos , Neoplasias Hipofisárias/patologia , Temozolomida/uso terapêutico , beta Catenina/metabolismo
4.
Tumour Biol ; 44(1): 85-105, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35811548

RESUMO

INTRODUCTION: Prolactinomas are the most frequent pituitary tumor subtype. Despite most of them respond to medical treatment, a proportion are resistant and become a challenge in clinical management. Wnt/ß-Catenin pathway has been implicated in several cancers including pituitary tumors and other sellar region malignancies. Interestingly, Wnt/ß-Catenin inhibition augments the cytotoxicity of the chemotherapeutic agent Temozolomide (TMZ) in different cancers. TMZ is now being implemented as rescue therapy for aggressive pituitary adenoma treatment. However, the molecular mechanisms associated with TMZ action in pituitary tumors remain unclear. OBJECTIVES: Our aims in the present study were to evaluate differential ß-Catenin expression in human resistant prolactinomas and Wnt/ß-Catenin signaling activation and involvement in Prolactin (PRL) secreting experimental models treated with TMZ. RESULTS: We first evaluated by immunohistochemistry ß-Catenin localization in human resistant prolactinomas in which we demonstrated reduced membrane ß-Catenin in prolactinoma cells compared to normal pituitaries, independently of the Ki-67 proliferation indexes. In turn, in vivo 15 mg/kg of orally administered TMZ markedly reduced PRL production and increased prolactinoma cell apoptosis in mice bearing xenografted prolactinomas. Intratumoral ß-Catenin strongly correlated with Prl and Cyclin D1, and importantly, TMZ downregulated both ß-Catenin and Cyclin D1, supporting their significance in prolactinoma growth and as candidates of therapeutic targets. When tested in vitro, TMZ directly reduced MMQ cell viability, increased apoptosis and produced G2/M cell cycle arrest. Remarkably, ß-Catenin activation and VEGF secretion were inhibited by TMZ in vitro. CONCLUSIONS: We concluded that dopamine resistant prolactinomas undergo a ß-Catenin relocalization in relation to normal pituitaries and that TMZ restrains experimental prolactinoma tumorigenicity by reducing PRL production and ß-Catenin activation. Together, our findings contribute to the understanding of Wnt/ß-Catenin implication in prolactinoma maintenance and TMZ therapy, opening the opportunity of new treatment strategies for aggressive and resistant pituitary tumors.


Assuntos
Neoplasias Hipofisárias , Prolactinoma , Animais , Ciclina D1 , Humanos , Camundongos , Modelos Teóricos , Neoplasias Hipofisárias/patologia , Prolactina/metabolismo , Prolactina/uso terapêutico , Prolactinoma/tratamento farmacológico , Prolactinoma/metabolismo , Prolactinoma/patologia , Temozolomida/farmacologia , Temozolomida/uso terapêutico , beta Catenina
5.
Arch Endocrinol Metab ; 64(5): 614-622, 2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-34033303

RESUMO

The usual clinical presentation of non-functioning pituitary adenoma (NFPA) consists of symptoms of mass effect and hypopituitarism. NFPA is a rare condition in young women and an uncommon complication during pregnancy. We present the outcome of three patients with NFPA during pregnancy. Case 1: a 38-year-old woman was referred at 32nd week of spontaneous pregnancy because of diagnosis of a pituitary macroadenoma discovered in the context of progressive visual loss. Hormonal deficiency and hypersecretion were ruled out. Prolactin levels were high as expected. She developed diplopia and severe headache despite the use of dopamine agonists and corticosteroids, so pregnancy was interrupted at 34th week. After an uncomplicated delivery of a healthy newborn, transsphenoidal surgery was performed. The pathology was consistent with a gonadotroph adenoma. She recovered visual field, and remained with normal pituitary function. Postsurgical tumor remnant increased in size during the follow-up. Case 2: a 34-year-old woman was referred due to secondary amenorrhea and galactorrhea. A macroadenoma with suprasellar extension was discovered. Transsphenoidal surgery confirmed a gonadotroph adenoma. Two years after surgery she had a normal pregnancy. Six years after surgery a small tumor recurrence occurred. Case 3: a 23-year-old woman was referred due to a microincidental pituitary adenoma. Laboratory testing was normal. No findings on physical examination. A wait and see approach was decided. Two years after diagnosis, the patient got pregnant without complications. Image remained stable. This article may contribute new cases and provides an extensive review of NFPA during pregnancy.


Assuntos
Adenoma , Galactorreia , Hipopituitarismo , Neoplasias Hipofisárias , Adenoma/cirurgia , Adulto , Feminino , Humanos , Hipopituitarismo/etiologia , Recém-Nascido , Recidiva Local de Neoplasia , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/cirurgia , Gravidez , Adulto Jovem
6.
Arch. endocrinol. metab. (Online) ; 64(5): 614-622, Sept.-Oct. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1131135

RESUMO

SUMMARY The usual clinical presentation of non-functioning pituitary adenoma (NFPA) consists of symptoms of mass effect and hypopituitarism. NFPA is a rare condition in young women and an uncommon complication during pregnancy. We present the outcome of three patients with NFPA during pregnancy. Case 1: a 38-year-old woman was referred at 32nd week of spontaneous pregnancy because of diagnosis of a pituitary macroadenoma discovered in the context of progressive visual loss. Hormonal deficiency and hypersecretion were ruled out. Prolactin levels were high as expected. She developed diplopia and severe headache despite the use of dopamine agonists and corticosteroids, so pregnancy was interrupted at 34th week. After an uncomplicated delivery of a healthy newborn, transsphenoidal surgery was performed. The pathology was consistent with a gonadotroph adenoma. She recovered visual field, and remained with normal pituitary function. Postsurgical tumor remnant increased in size during the follow-up. Case 2: a 34-year-old woman was referred due to secondary amenorrhea and galactorrhea. A macroadenoma with suprasellar extension was discovered. Transsphenoidal surgery confirmed a gonadotroph adenoma. Two years after surgery she had a normal pregnancy. Six years after surgery a small tumor recurrence occurred. Case 3: a 23-year-old woman was referred due to a microincidental pituitary adenoma. Laboratory testing was normal. No findings on physical examination. A wait and see approach was decided. Two years after diagnosis, the patient got pregnant without complications. Image remained stable. This article may contribute new cases and provides an extensive review of NFPA during pregnancy.


Assuntos
Humanos , Feminino , Gravidez , Recém-Nascido , Adulto , Adulto Jovem , Adenoma/cirurgia , Galactorreia , Hipopituitarismo/etiologia , Neoplasias Hipofisárias/cirurgia , Neoplasias Hipofisárias/diagnóstico por imagem , Recidiva Local de Neoplasia
8.
Oncotarget ; 8(34): 57072-57088, 2017 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-28915655

RESUMO

Pituitary adenomas are among the most frequent intracranial neoplasms and treatment depends on tumor subtype and clinical features. Unfortunately, non responder cases occur, then new molecular targets are needed. Notch system component expression and activation data are scarce in pituitary tumorigenesis, we therefore aimed to characterize Notch system in pituitary tumors of different histotype. In human pituitary adenomas we showed NOTCH1-4 receptors, JAGGED1 ligand and HES1 target gene expression with positive correlations between NOTCH1,2,4 and HES1, and NOTCH3 and JAGGED1 denoting Notch system activation in a subset of tumors. Importantly, NOTCH3 positive cells were higher in corticotropinomas and somatotropinomas compared to non functioning adenomas. In accordance, Notch activation was evidenced in AtT20 tumor corticotropes, with higher levels of NOTCH1-3 active domains, Jagged1 and Hes1 compared to normal pituitary. In the prolactinoma cell lines GH3 and MMQ, in vivo GH3 tumors and normal glands, Notch system activation was lower than in corticotropes. In MMQ cells only the NOTCH2 active domain was increased, whereas NOTCH1 active domain was higher in GH3 tumors. High levels of Jagged1 and Dll1 were found solely in GH3 cells, and Hes1, Hey1 and Hey2 were expressed in a model dependent pattern. Prolactinomas harbored by lacDrd2KO mice expressed high levels of NOTCH1 active domain and reduced Hes1. We show a differential expression of Notch system components in tumoral and normal pituitaries and specific Notch system involvement depending on adenoma histotype, with higher activation in corticotropinomas. These data suggest that targeting Notch pathway may benefit non responder pituitary adenomas.

9.
Int J Endocrinol ; 2014: 608497, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25505910

RESUMO

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.

10.
Pituitary ; 16(3): 303-10, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22886682

RESUMO

The role of angiogenesis in human pituitary tumor progression is questioned. Our aim was to characterize the morphologic changes that occur in the vasculature of pituitary adenomas, in correlation with the expression of nestin, a protein found in endothelial cells of newly formed vessels of developing organs. We also evaluated the relation of angiogenic markers and nestin with Ki-67 index. Immunohistochemical studies were performed on paraffin embedded samples of 47 pituitary adenomas and six normal pituitaries. We determined microvessel density (number of CD31+ or CD34+ vessels per square millimetre), vascular area (cumulative area occupied by vessels), average vessel size, and further classified vessels as small (< 100 µm2) or large (> 100 µm2). We correlated the above parameters with nestin expression and Ki-67 index. Lower vascular area compared to normal tissue was found in adenomas (p < 0.05). Interestingly, pituitary adenomas had significantly more small vessels than control pituitaries (p < 0.04 for CD31 and CD34). In tumors many capillaries were positive for nestin, while scarce staining was detected in controls, so that nestin positive area was significantly higher in tumors. Furthermore, nestin area correlated positively with the % of small vessels. Ki-67 correlated neither with vascular area nor with nestin expression. In human pituitary tumors there was a predominance of small capillaries in correlation with increased expression of the progenitor marker nestin. We suggest that angiogenesis is an active process in these tumors, in spite of their low total vascular area when compared to normal pituitaries.


Assuntos
Adenoma/metabolismo , Nestina/metabolismo , Neoplasias Hipofisárias/metabolismo , Adulto , Idoso , Vasos Sanguíneos/metabolismo , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Antígeno Ki-67/metabolismo , Pessoa de Meia-Idade , Neovascularização Patológica , Adulto Jovem
11.
Rev. argent. neurocir ; 25(1): 31-38, ene.-mar. 2011. ilus
Artigo em Espanhol | LILACS | ID: lil-605647

RESUMO

Objetivo: analizar en la casuística de los últimos 5 años las distintas variantes que serían determinantes de su desarrollo, agresividad, invasión. Recidivas, la coexistencia con otras patologías, del tratamiento realizado, y efectuar una revisión bibliográfica de la literatura. Material y método: en el período 2005-2009, fueron intervenidos, quirúrgicamente 76 pacientes con diagnóstico de Meningioma, se hallaron 5 con grado II-III. En ellos se consideraron las siguientes variables: sexo, edad, localización, diagnóstico histopatológico, Ki 67, genética y biología molecular, tratamiento quirúrgico, recidiva, radioterapia, terapéutica hormonal y asociación a otras patologías. Resultados: los 5 pacientes (7%) con diagnóstico histológico de Meningiomas agresivos fueron de sexo femenino (100% de los casos), con una edad media de 51 años. En cuanto a la localización: 3 casos se originaron en la hoz cerebral, 1 caso a nivel de la convexidad y 1 caso a nivel columna dorsal. En el 100% de las muestras se realizó Ki 67, EMA, VIM, y receptores a progesterona. La anatomía patológica reveló 4 atípicos y 1 anaplásico. El 90% de los casos presentó recidiva. El tratamiento fue resección quirúrgica seguido de radioterapia postrecidiva, excepto a nivel espinal. En una paciente se asoció a cáncer de mama y otra a cirugía de absceso cerebral. Conclusión: factores genéticos, hormonales y de reparación celular se asocian a la formación de estos tumores. Los actuales avances en biología molecular permitirán tratamientos seleccionados para cada paciente según las características tumorales, hasta la llegada de ese futuro, la cirugía seguida de radioterapia, continúa siendo el tratamiento de elección...


Assuntos
Meningioma , Biologia Molecular , Terapêutica
12.
Rev. argent. neurocir ; 24(3): 111-116, jul.-sept. 2010. ilus
Artigo em Espanhol | LILACS | ID: lil-583691

RESUMO

Objetivo. Reportar 2 casos de pacientes con diagnóstico de síndrome de Tolosa-Hunt y realizar una revisión de la literatura de esta infrecuente patología. Descripción. Caso 1: Paciente femenina de 21 años de edad que consulto por oftalmoplejía dolorosa de 72 hs de evolución sin compromiso visual. Se realizó IRM de encéfalo que evidenció el engrosamiento difuso con realce postcontraste del seno cavernoso izquierdo. Se interpretó el cuadro como un STH. Caso 2: Paciente masculino de 45 años de edad que consultó por oftalmoplejía dolorosa de 2 meses de evolución y amaurosis del ojo derecho. Se le solicitó IRM de encéfalo que evidenció el engrosamiento difusodel seno cavernoso derecho. La retinografía evidenció la atrofia de la papila de dicho ojo. El cuadro se interpretó como un STH asociado a una neuritis óptica homolateral. Intervención. Caso 1. Inicio tratamiento con corticoides y carbemazepina lográndose a los 3 meses recuperación total sin recaídas posteriores. Caso 2. Se inicio tratamiento con corticoides. Actualmente se encuentra en control por consultorios presentando mejoría significativa de los síntomas sin mejoría de la amaurosis de ingreso. Conclusión. El STH es una entidad poco frecuente, con un probable origen autoinmunitario. Existen diversas causas que pueden simular este síndrome. Es mandatorio el análisis exhaustivo de estos pacientes, a fin de descartar otras patologías.


Assuntos
Neuralgia , Oftalmoplegia , Síndrome de Tolosa-Hunt
13.
Rev. argent. neurocir ; 24(3): 137-140, jul.-sept. 2010. ilus
Artigo em Espanhol | LILACS | ID: lil-583694

RESUMO

Objective. We developed a bibliographic research of this rarely and highly aggressive entity, showing our experience and taking into account the special case of one patient, who developed an extremely aggressive disease. Description. Patient of 71 years that consults our department for left cavernous syndrome associated with moderate headache and bilateral visual accuracy diminish. Pituitary IRM was performed showing a homogeneous selar tumor that causes slight mass effect towards optic quiasm. Both cavernous sinuses were compromised. Intervention.Trasfenoidal surgery was performed, reaching the diagnosis of acidophil stem cell adenoma. The patient is dismissed. One week later and because of the development of sudden visual loss she was admitted once again. Pituitary IRM was performed showing a massive growth of the known lesion, requiring transcranial approach. Important mass reduction was achieved but our patient evolution was erratic. Three weeks after surgery we decided to repeat the IRM where we discovered the great mass reduction achieved in the second surgery did not reflect the voluminous lesion shown. One week later the patient died. Conclusion. Acidophil stem cell adenomas of the pituitary gland are mixed PRL/GH lesions, but because its immaturity non functional secreting hormones are produced; this is why these patients do not express physiognomic changes. We should think of this pathology in any pituitary tumor with low PRL-GH expression and few physiognomic changes, and aggressive natural evolution.


Assuntos
Adenoma Acidófilo , Neoplasias , Células-Tronco
14.
Endocr Pathol ; 21(3): 154-60, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20473646

RESUMO

Pituitary tumors are usually less vascularized than the normal pituitary, and the role of angiogenesis in these adenomas is contentious. Appraisal of microvascular density and expression of the potent angiogenic vascular endothelial growth factor (VEGF) by immunohistochemistry has yielded controversial results, as a broad spectrum of immunostaining can be found. We determined the protein expression of VEGF and CD31, an endothelial marker, in a series of 56 surgically removed pituitary adenomas using Western blot assay. Prolactinomas had higher VEGF protein expression compared to nonfunctioning or ACTH- and GH-secreting adenomas, while CD31 was similar in the different adenoma histotypes. VEGF and CD31 were not affected by sex, age, years of adenoma evolution, or proliferation rate (Ki67 and PCNA) for all adenoma types. Only in nonfunctioning adenomas CD31 concentration increased significantly with age. There was a positive correlation between CD31 and VEGF expression when all adenoma histotypes were considered, or when prolactinomas and nonfunctioning adenomas were evaluated separately. The positive association of VEGF and CD31 expression suggests the participation of angiogenesis in adenoma development, while epithelial cell proliferation in pituitary tumors is not directly related to VEGF or CD31 expression, and other factors, such as primary genetic alterations may be involved.


Assuntos
Adenoma/metabolismo , Biomarcadores Tumorais/análise , Neoplasias Hipofisárias/metabolismo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/biossíntese , Fator A de Crescimento do Endotélio Vascular/biossíntese , Adulto , Western Blotting , Feminino , Humanos , Masculino
15.
Rev. argent. neurocir ; 21(3): 117-119, jul.-sept. 2007. ilus
Artigo em Espanhol | LILACS | ID: lil-511271

RESUMO

Objectives: Presentation of two cases of a pathology of the skull base of very low frequency in world-wide literature. Material and methods: First case: male patient, 25 years old. The RMN of brain showed a lesion in selar, supra and paraselar location. Second case: female patient, 40 years old. The RMN of brain showed right temporal lesion with adjacent bone commitment. Results: Both patients were treated surgically, anatomopathologyic diagnosis was giant cells tumor (GCT). Conclusion: The GCT are generally benign, locally aggressive, the surgical excision has proved to be the most effective treatment. The presentation of this work is due to the scant bibliography reported until the moment on GCT of the skull base.


Assuntos
Tumores de Células Gigantes , Granuloma , Imageamento por Ressonância Magnética , Radioterapia
16.
Front Horm Res ; 35: 22-31, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16809920

RESUMO

Bone morphogenetic protein-4 (BMP-4), a member of the transforming growth factor-Beta(TGF-Beta) family, is overexpressed in different prolactinoma models and induces the development of these lineage adenomas. SMAD proteins activated by growth factors of the TGF-Beta and BMP family interact with estrogen receptors to stimulate the proliferation of prolactin and growth hormone-secreting cells. Furthermore, BMP-4 presents differential expression in normal and adenomatous corticotropes and inhibitory action on corticotropinoma cell proliferation. Moreover, BMP-4 mediates the antiproliferative action of retinoic acid in these cells. The present review highlights not only the crucial and opposite role of BMP-4 in the progression of pituitary adenomas but also that BMP-4 and retinoic acid interaction might serve as a potential new mechanism target for therapeutic approaches for Cushing disease.


Assuntos
Proteínas Morfogenéticas Ósseas/fisiologia , Doenças da Hipófise/etiologia , Hormônio Adrenocorticotrópico/metabolismo , Animais , Proteína Morfogenética Óssea 4 , Proteínas Morfogenéticas Ósseas/metabolismo , Expressão Gênica , Humanos , Modelos Biológicos , Neurônios/metabolismo , Hipófise/citologia , Hipófise/crescimento & desenvolvimento , Hipófise/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Fator de Crescimento Transformador beta/fisiologia , Tretinoína/farmacologia
17.
Endocrinology ; 147(1): 247-56, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16195406

RESUMO

The molecular mechanisms governing the pathogenesis of ACTH-secreting pituitary adenomas are still obscure. Furthermore, the pharmacological treatment of these tumors is limited. In this study, we report that bone morphogenetic protein-4 (BMP-4) is expressed in the corticotrophs of human normal adenohypophysis and its expression is reduced in corticotrophinomas obtained from Cushing's patients compared with the normal pituitary. BMP-4 treatment of AtT-20 mouse corticotrophinoma cells has an inhibitory effect on ACTH secretion and cell proliferation. AtT-20 cells stably transfected with a dominant-negative form of the BMP-4 signal cotransducer Smad-4 or the BMP-4 inhibitor noggin have increased tumorigenicity in nude mice, showing that BMP-4 has an inhibitory role on corticotroph tumorigenesis in vivo. Because the activation of the retinoic acid receptor has an inhibitory action on Cushing's disease progression, we analyzed the putative interaction of these two pathways. Indeed, retinoic acid induces both BMP-4 transcription and expression and its antiproliferative action is blocked in Smad-4dn- and noggin-transfected Att-20 cells that do not respond to BMP-4. Therefore, retinoic acid induces BMP-4, which participates in the antiproliferative effects of retinoic acid. This new mechanism is a potential target for therapeutic approaches for Cushing's disease.


Assuntos
Adenoma/patologia , Proteínas Morfogenéticas Ósseas/farmacologia , Proteínas Morfogenéticas Ósseas/fisiologia , Síndrome de Cushing/patologia , Neoplasias Hipofisárias/patologia , Tretinoína/farmacologia , Animais , Proteína Morfogenética Óssea 4 , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Imuno-Histoquímica , Camundongos , Hipófise/patologia , Hipófise/fisiologia , Valores de Referência
18.
Rev. argent. neurocir ; 18(3): 105-108, jul.-sept. 2004. ilus
Artigo em Espanhol | LILACS | ID: lil-390627

RESUMO

Objective: to present a 38 year old female patient, with central diabetes insipidus, panhipopituitarims, and severely impaired vision. Description: magnetic resonance imaging demonstrated a large mass involving the hypothalamus, infundibulum, optic nerves, and chiasm. Intervention: at surgery the optic pathways were found to be grossly involved within the inflammatory mass. Histological examination demonstrated anonspecific, mixed inflammatory infiltrate, composed predominantly of lymphocytes and plasma cells. She responded dramatically to dexamethasone, with mass reduction on serial imaging studies and vision improvement. In addition, she received hormone replacement therapy. Infundibulohypophisitis is a rare disease. Surgical biopsy and dexamethasone were an effective treatment


Assuntos
Humanos , Feminino , Dexametasona , Neoplasias Hipotalâmicas , Doenças da Hipófise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA