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INTRODUÇÃO: Os tumores neuroendócrinos (TNE) são neoplasias, com origem mais comum no trato gastrointestinal, que podem cursar com liberação de hormônios associado a sintomas, levando a síndrome carcinoide, com incidência anual estimada em 0,25/1.000.000 na Europa (ano de 2008). As manifestações clínicas mais comuns incluem diarreia secretória e rubor súbito, mas a diarreia é considerada mais debilitante com potencial risco de morte. Quando o tratamento curativo com ressecção completa não é viável pela presença de doença metastática, o tratamento é direcionado para o controle dos sintomas da síndrome carcinoide e os análogos da somatostatina (octreotida ou lanreotida) são considerados terapia de primeira linha na SC. PERGUNTAS DE PESQUISA: O acetato de octreotida de liberação prolongada (octreotida LAR) e o acetato de lanreotida de liberação prolongada (lanreotida LP) são eficazes, seguros e custo-efetivos para o tratamento dos sintomas relacionados à SC associados ao TNE gastroenteropancreático funcional em pacientes adultos? EVIDÊNCIAS CLÍNICAS: Foram selecionados três ensaios clínico

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Introducción: El cáncer de tiroides se posiciona como una de las neoplasias más prevalentes en Ecuador, manifestándose típicamente en la cuarta década de vida, con una mayor inciden-cia en mujeres. El subtipo histológico predominante es el papilar (CPT), y diversos estudios han evidenciado que hasta un 80% de los casos de CPT presentan la mutación BRAF. Esta mutación se ha asociado con factores de pronóstico desfavorable, como la presencia de me-tástasis ganglionares, estadíos tumorales avanzados, extensión extratiroidea y característi-cas histológicas agresivas. Además, se ha observado una relación con una mayor tasa de recurrencia y una respuesta reducida al tratamiento con yodo. Ante este contexto, esta inves-tigación se propone analizar la distribución de la mutación BRAF según características epide-miológicas e histopatológicas en pacientes con diagnóstico de cáncer papilar de tiroides en Ecuador. Materiales y métodos: Este estudio se llevó a cabo de manera descriptiva y retrospectiva, abarcando a pacientes con diagnóstico de cáncer papilar de tiroides a quienes se les practicó el análisis genético para la detección de la mutación BRAF. La muestra incluyó 106 historias clínicas que cumplían con los criterios de selección establecidos Resultados: La evaluación de las historias clínicas reveló la presencia de la mutación BRAF en el 75% de los casos. Este porcentaje fue más elevado en mujeres, individuos mayores de 45 años y residentes en áreas urbanas. Respecto a la ocupación, la mayoría de los pacientes se dedicaba a labores de limpieza y no presentaban antecedentes personales de exposición a radiación ionizante ni antecedentes oncológicos familiares. El 84% se encontraba en la etapa clínica I, y en su mayoría, la neoplasia estaba localizada en el lóbulo tiroideo derecho.Conclusión:Este análisis subraya la imperiosa necesidad de identificar los factores de riesgo vinculados con la aparición del carcinoma papilar de tiroides en la población ecuatoriana. Los resultados indican una prevalencia significativa de la mutación BRAF, lo que subraya su rele-vancia comomarcador pronóstico en esta enfermedad. Estos hallazgos pueden contribuir a una mejor comprensión de la epidemiología y la patogenia del cáncer de tiroides, así como a la mejora de las estrategias de prevención y tratamiento en el ámbito local.

Introduction: Thyroid cancer is positioned as one of the most prevalent neoplasms in Ecuador, typically manifesting in the fourth decade of life, with a higher incidence in women. The pre-dominant histological subtype is papillary carcinoma (PTC), and various studies presentshown that up to 80% of PTC cases present the BRAF mutation. This mutation has been as-sociated with unfavorable prognostic factors, such as the presence of lymph node metasta-ses, advanced tumor stages, extrathyroidal extension, and aggressive histologicalfeatures. Additionally, a correlationhas been observed with a higher recurrence rate and a reduced re-sponse toiodine treatment. Given this context, this research aims to analyze the distribution of the BRAF mutation according to epidemiological and histopathological characteristics in patients diagnosed with papillary thyroid cancer in Ecuador. Materials and methods: This retrospective descriptive study involved the analysis of genetic data from 106 medical records of patients diagnosed with papillary thyroid cancer who under-went BRAF mutation detection. The sample was selected based on established criteria. Results: Evaluation of medical records revealed the presence of the BRAF mutation in 75% of cases. This percentage was higher in women, individuals over 45 years of age, and residents in urban areas. Regarding occupation, most patients were dedicated to cleaning work and had no personal history of exposure to ionizing radiation orafamily history of cancer.Additionally, 84% of the patients were in clinical stage I and the neoplasmswerelocated in the right thyroid lobe.Conclusion: This analysis highlights the urgent need to identify risk factors linked to the ap-pearance of papillary thyroid carcinoma in the Ecuadorian population. The results indicate a significant prevalence of the BRAF mutation, underlining its relevance as a prognostic marker in this disease. These findings may contribute to a better understanding of the epidemiology and pathogenesis of thyroid cancerleadingtoimprovementsinprevention and treatment strategies at the local level.

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Thyroid carcinomas are a common form of endocrine neoplasia in dogs. In the present study, we combined histopathology with immunohistochemistry (IHC) to search for the presence of oestrogen receptor alpha (ORα), Cox-2 and Ki67 in canine thyroid carcinomas. Forty-eight thyroid carcinomas were diagnosed throughout the study period. Thyroglobulin and calcitonin IHC distinguished between thyroid tumours with a follicular and medullary (C-cell) origin, respectively. IHC-based diagnosis showed that 42 (87.50%) of the cases were follicular cell carcinoma. In these cases, the follicular-compact pattern was the most frequent (n = 20/42; 47.62%) and six cases (12.5%) were medullary cell (C-cell) carcinomas. Both medullary (C-cell) and follicular carcinomas expressed Ki67 and Cox-2. No differences were observed between medullary and follicular carcinomas with respect to expression of Ki67 (P = 0.34) and Cox-2 (P = 0.9523) markers. A total of 4.17% (n = 2/48) of thyroid carcinomas showed positive nuclear labelling for ORα, suggesting that oestrogen does not directly participate in the pathogenesis of canine thyroid neoplasia.

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Immune checkpoint inhibitors are agents that act by inhibiting the mechanisms of immune escape displayed by various cancers. The success of immune checkpoint inhibitors against several tumors has promoted a new treatment strategy in clinical oncology, and this has encouraged physicians to increase the number of patients who receive the immune checkpoint therapy. In the present article, we review the main concepts regarding immune checkpoint mechanisms and how cancer disrupts them to undergo immune escape. In addition, we describe the most essential concepts related to immune checkpoint inhibitors. We critically review the literature on preclinical and clinical studies of the immune checkpoint inhibitors as a treatment option for thyroid cancer, ovarian carcinoma, pancreatic adenocarcinoma, adrenocortical carcinoma and neuroendocrine tumors. We present the challenges and the opportunities of using immune checkpoint inhibitors against these endocrine malignancies, highlighting the breakthroughs and pitfalls that have recently emerged.

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Autophagy is an important intracellular process involving the degradation of cytoplasmic components. It is involved in both physiological and pathological conditions, including cancer. The role of autophagy in cancer is described as a 'double-edged sword,' a term that reflects its known participation in tumor suppression, tumor survival and tumor cell proliferation. Available research regarding autophagy in endocrine cancer supports this concept. Autophagy shows promise as a novel therapeutic target in different types of endocrine cancer, inhibiting or increasing treatment efficacy in a context- and cell-type-dependent manner. At present, however, there is very little research concerning autophagy in endocrine tumors. No research was reported connecting autophagy to some of the tumors of the endocrine glands such as the pancreas and ovary. This review aims to elucidate the roles of autophagy in different types of endocrine cancer and highlight the need for increased research in the field.

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El paraganglioma es un tumor neuroendocrino poco frecuente que puede desarrollarse en diversos sitios del organismo. Alrededor del 97 por ciento son benignos y se curan mediante la extirpación quirúrgica, y el restante 3 por ciento son malignos, y provocar metástasis a distancia. Alrededor del 75 por ciento son esporádicos y el restante 25 por ciento son hereditarios (y tienen una mayor probabilidad de ser múltiples y de desarrollo a una edad temprana). Pueden tener predisposición genética asociada a síndromes tumorales familiares, como la neoplasia endocrina múltiple tipo 2, el síndrome de Von Hippel-Lindau y la neurofibromatosis tipo 1, o mutaciones específicas relacionadas solamente con el desarrollo de paragangliomas. Comparado con la forma de aparición esporádica, la presentación familiar tiene tendencia a aparecer en edades más jóvenes, y a tener múltiple localización. Por la poca disponibilidad de recursos y lo costoso de las investigaciones utilizadas, son de difícil diagnóstico en nuestro medio, por lo cual no se excluye que exista un subregistro en el número de casos que se puedan presentar, razón por la que es importante siempre -ante la sospecha clínica- pensar en su probable confirmación diagnóstica y situación. Los estudios de imágenes y la medición de la producción no fisiológica de catecolaminas, pueden ayudar en el diagnóstico de esta entidad. Las principales modalidades de tratamiento son: la cirugía, la embolización y la radioterapia. Con el objetivo de actualizar y sugerir una guía de tratamiento se realizó la presente revisión(AU)

Paraganglioma is a rare neuroendocrine tumor that may occur in several parts of the body. Roughly 97 percent of these tumors are benign and can be excised through surgery whereas 3 percent of them are malignant and cause distant metastasis. Almost 75 percent are sporadic and the remaining 25 percent are hereditary (more likely to be multiple and developed at early ages). They may be genetically predisposed and associated to family tumor syndromes such as type 2 multiple endocrine neoplasia, Von Hippel-Lindau syndrome and type 1 neurofibromatosis or specific mutations related to development of paragangliomas. When compared to the sporadic occurrence, the family presentation tends to appear at younger ages, with multiple locations. Owing to the low resource availability and the high cost of research, these tumors are difficult to be diagnosed in our conditions, so there may be failures in registering the real number of cases; this is the reason why it is always important to think on possible diagnostic confirmation when clinical suspicion of paraganglioma arises. Imaging studies and measurement of the non-physiological production of catecholamines may help in the diagnosis of this disease. The main therapeutical modalities are surgery, embolization and radiotherapy. The present review was intended to update this topic and to submit a treatment guideline(AU)

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El paraganglioma es un tumor neuroendocrino poco frecuente que puede desarrollarse en diversos sitios del organismo. Alrededor del 97 por ciento son benignos y se curan mediante la extirpación quirúrgica, y el restante 3 por ciento son malignos, y provocar metástasis a distancia. Alrededor del 75 por ciento son esporádicos y el restante 25 por ciento son hereditarios (y tienen una mayor probabilidad de ser múltiples y de desarrollo a una edad temprana). Pueden tener predisposición genética asociada a síndromes tumorales familiares, como la neoplasia endocrina múltiple tipo 2, el síndrome de Von Hippel-Lindau y la neurofibromatosis tipo 1, o mutaciones específicas relacionadas solamente con el desarrollo de paragangliomas. Comparado con la forma de aparición esporádica, la presentación familiar tiene tendencia a aparecer en edades más jóvenes, y a tener múltiple localización. Por la poca disponibilidad de recursos y lo costoso de las investigaciones utilizadas, son de difícil diagnóstico en nuestro medio, por lo cual no se excluye que exista un subregistro en el número de casos que se puedan presentar, razón por la que es importante siempre -ante la sospecha clínica- pensar en su probable confirmación diagnóstica y situación. Los estudios de imágenes y la medición de la producción no fisiológica de catecolaminas, pueden ayudar en el diagnóstico de esta entidad. Las principales modalidades de tratamiento son: la cirugía, la embolización y la radioterapia. Con el objetivo de actualizar y sugerir una guía de tratamiento se realizó la presente revisión(AU)

Paraganglioma is a rare neuroendocrine tumor that may occur in several parts of the body. Roughly 97 percent of these tumors are benign and can be excised through surgery whereas 3 percent of them are malignant and cause distant metastasis. Almost 75 percent are sporadic and the remaining 25 percent are hereditary (more likely to be multiple and developed at early ages). They may be genetically predisposed and associated to family tumor syndromes such as type 2 multiple endocrine neoplasia, Von Hippel-Lindau syndrome and type 1 neurofibromatosis or specific mutations related to development of paragangliomas. When compared to the sporadic occurrence, the family presentation tends to appear at younger ages, with multiple locations. Owing to the low resource availability and the high cost of research, these tumors are difficult to be diagnosed in our conditions, so there may be failures in registering the real number of cases; this is the reason why it is always important to think on possible diagnostic confirmation when clinical suspicion of paraganglioma arises. Imaging studies and measurement of the non-physiological production of catecholamines may help in the diagnosis of this disease. The main therapeutical modalities are surgery, embolization and radiotherapy. The present review was intended to update this topic and to submit a treatment guideline(AU)

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Los tumores neuroendocrinos en la glándula mamaria, representan menos del 2 por ciento de las lesiones malignas que se presentan en la mama, un 30 por ciento pueden ser metastásicos, principalmente de tumores carcinoides intestinales. Se presenta el caso de una paciente femenina 64 años con el antecedente de carcinoma de mama izquierda pT1N1Mo Estadio II A, se le practicó en el año 2000 cirugía preservadora, recibió tratamiento sistémico y radioterapia, presentando recaída local, histológicamente y por inmuhistoquímica, como tumor neuroendocrino, en mayo de 2008 se le realiza mastectomía simple izquierda. Actualmente viva y sin enfermedad. Los tumores neuroendocrinos pueden presentarse en localizaciones extra intestinales. El diagnóstico debe realizarse por histología y confirmado con técnicas de inmunohistoquímica, son tumores de baja agresividad biológica, no se presentan síntomas sistémicos por liberación de hormonas como en otras localizaciones, y el tratamiento debe basarse en el estadio clínico de la enfermedad al momento del diagnóstico.

Neuroendocrines in the mammary gland tumors represent less than 2 percent of malignant injuries, which 30 percent can be source metastatic, mainly tumors intestinal carcinoid. The clinical of a female patient case 64 years old are presented with the antecedent of pT1N1Mo Stadium II A left breast carcinoma who was practiced in the year 2000 sparing surgery, received systemic therapy and radiotherapy, featuring local relapse, histological and inmuhistochemestry, as neuroendocrines, practicing it in May of 2008 mastectomy left, currently living and without disease tumor. Neuroendocrines tumors can occur in extra intestinal in lung, uterine and less common in the mammary gland neck locations. The diagnosis must be made by histology and confirmed with Immunohistochemistry techniques, are tumors of low biological aggression, not have systemic symptoms by release of hormones as in other locations, and treatment must be based on the clinical stage of the disease at the time of diagnosis.

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INTRODUCTION: Somatostatin receptors are expressed in a large number of human tumours. The somatostatin receptors types 1-5 expression in a series including 100 gastro-entero-pancreatic endocrine tumours were analysed. METHODS: From a prospectively built database of patients with gastro-entero-pancreatic endocrine tumours referred from three institutions, 100 cases with clinical and pathological data were selected. Somatostatin receptors expression by immunohistochemistry with somatostatin receptor types 1-5 antibodies in tissue paraffin sections were studied and correlated with the histological diagnosis according to the WHO classification, location and functional status. RESULTS: Of the 100 cases, 67 were gastrointestinal tumours, 25 pancreatic and 8 liver metastasis of unknown origin. Thirty-one of them were functioning tumours: 2 insulinomas, 5 gastrinomas, 1 glucagonoma and 23 carcinoids. Somatostatin receptors expression was observed in 94 tumours. The six negative cases were all non-functioning tumours. Somatostatin receptors 2a and 5 were highly expressed (86 and 62%, respectively), and surprisingly found even in poorly differentiated endocrine carcinomas. Somatostatin receptors expression was less frequent in pancreatic than in gastrointestinal tumours. Well-differentiated neoplasms had a higher density of somatostatin receptors. Only SSTR2a showed membrane staining. CONCLUSIONS: Immunohistochemistry revealed that somatostatin receptors were highly expressed in both primary and metastatic gastro-entero-pancreatic endocrine tumours with heterogeneous staining distribution. It proved to be a reliable technique even in small tumour samples.

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The relationship between environmental factors and health is well known. Rural environmental influences on reproductive health have been properly proved, both in animals and humans. In Latin America, few studies have been conducted in this area. The current project is based on the description of relationships between reproductive health and environmental factors in rural populations, characterized by specific environmental characteristics. Three variables were evaluated: male-to-female birth ratio, male urogenital malformations (cryptorchidism and hypospadias), and endocrine-related cancer incidence. Five rural communities in the Pampa Humeda in Argentina were selected, and the data were compared to the national mean. Biomedical data and environmental risk factors were correlated through a geographic information system. The ratio of male to female births did not show any differences. Malformations showed very significant differences. Endocrine-related cancers showed higher incidence rates compared to the national mean, particularly in some communities. In conclusion, there is a relationship between environmental factors and reproductive health conditions in this region.

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La relación entre factores ambientales y salud es un hecho reconocido. La influencia de ambientes rurales sobre la salud reproductiva ha sido fehacientemente probada en diferentes regiones del mundo, tanto en la fauna como en humanos. En América Latina pocas investigaciones han sido realizadas en este campo. El presente proyecto se establece sobre la base de la describir las relaciones entre salud reproductiva y factores ambientales en poblaciones rurales, caracterizada por aspectos ambientales particulares. Tres variables han sido evaluadas: relación de nacimientos masculinos/femeninos; incidencia de malformaciones uro-genitales masculinas (hipospadias y criptorquidias); e incidencia de cánceres hormono-dependientes. Se seleccionaron cinco comunidades rurales de la Pampa Húmeda de Argentina, comparándose los datos obtenidos con medias nacionales. Los datos bio-médicos y las fuentes ambientales de riesgo fueron relacionados entre sí a través de un sistema de geo-referenciación. La relación de nacimientos no mostró significación. Las malformaciones presentaron una muy significativa incidencia. Los cánceres hormono-dependientes presentaron incidencia mayores a las medias nacionales, particularmente en algunas de las comunidades estudiadas. Se concluye que existe una relación entre condiciones de salud reproductiva y factores ambientales en esta región.

The relationship between environmental factors and health is well known. Rural environmental influences on reproductive health have been properly proved, both in animals and humans. In Latin America, few studies have been conducted in this area. The current project is based on the description of relationships between reproductive health and environmental factors in rural populations, characterized by specific environmental characteristics. Three variables were evaluated: male-to-female birth ratio, male urogenital malformations (cryptorchidism and hypospadias), and endocrine-related cancer incidence. Five rural communities in the Pampa Humeda in Argentina were selected, and the data were compared to the national mean. Biomedical data and environmental risk factors were correlated through a geographic information system. The ratio of male to female births did not show any differences. Malformations showed very significant differences. Endocrine-related cancers showed higher incidence rates compared to the national mean, particularly in some communities. In conclusion, there is a relationship between environmental factors and reproductive health conditions in this region.

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BACKGROUND: Of all cancers, only 0.3% are carcinoid tumors of the small bowel. The diagnostic approach of these patients is difficult because they may appear asymptomatic for a long time and also because of the low specificity of the currently available diagnostic tests. We present a case in which the laparoscopic approach allowed not just the diagnosis but facilitated surgery. CASE REPORT: A 58-year-old male had 2 months with mid-intestinal subocclusive symptoms (late postprandial abdominal pain relieved by vomiting). No abnormalities were found on physical examinations or with laboratory tests. Barium plain x-rays and CT scan revealed a retention stomach and proximal dilation of the small bowel without demonstrating cause. Laparoscopically, we found a 5-cm jejunal tumor. We performed intestinal resection and anastomosis by mini-laparotomy (7 cm). There were no postoperative complications. Pathology report disclosed a well-differentiated neuroendocrine carcinoma. At 1-year follow-up there are no signs of tumor activity. CONCLUSIONS: Laparoscopic surgery contributes to diagnosis and facilitates the management of patients with mid-intestinal subocclusive disease. Due to previous reports, the frequency of small intestine carcinoids may be underestimated. There are carcinoid tumors 2 cm or larger without metastases at the time of diagnosis.

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Se presenta el caso de una paciente de 51 años con cuadro clínico de hipoglicemia por un probable insulinoma pancreático. Los exámenes de laboratorio confirmaron la sospecha de insulinoma, pero los estudios por imágenes no pudieron demostrar el tumor. Bajo estas circunstancias, la paciente tuvo abordaje laparoscópico y con la ayuda del ultrasonido intraoperatorio se localizó el tumor en el proceso uncinado del páncreas y, finalmente, se procedió a la enucleación laparoscópica.

The case of a 51-year-old woman with a clinical history of hipoglicemia causedby a presumed pancreatic insulinoma is reported. Laboratory tests pointed outfor a insulinoma, but imaginologic studies could not locate the tumor. Under this circumstances, the patient was laparoscopically approached. By means of the ultrasononography device the tumor was located at the uncinate process of the pancreas and, eventually treated by laparoscopic enucleation.

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OBJECTIVE: Melanotic schwannoma is a rare neoplasm, classifiable as a peripheral nerve sheath tumor, and differentiated from a typical schwannoma by heavy pigmentation. Psammoma bodies can be visualized in more than 50% of melanotic schwannomas. Half of patients with such "psammomatous melanotic schwannomas" have Carney complex, a dominantly transmitted autosomal disorder. Most recently, the tumor suppressor gene, PRKAR1A, coding for the Type 1alpha regulatory subunit of protein kinase A was found to be mutated in approximately half of the known Carney complex families. Although cranial schwannomas have been described in patients with Carney complex, their numbers are too small to be considered a definite part of the syndrome. Furthermore, only melanotic schwannomas with psammoma bodies are included as diagnostic criteria for Carney complex. The objective of this report is to communicate a case of trigeminal nonpsammomatous melanotic schwannoma as the first manifestation of Carney complex. CLINICAL PRESENTATION: A 34-year-old woman presented with odontalgia, right V3 hypoesthesia, V2 paresthesia, and diplopia. Magnetic resonance imaging scans of the brain revealed a small tumor with homogenous contrast in the right trigeminal pathway. INTERVENTION: We performed an extradural approach to the right cavernous sinus by a middle fossa approach. The lateral wall was opened between the cranial nerves, and a soft and black tumor was resected in a piecemeal fashion. Histology and immunohistochemical analysis of the tumor were compatible with melanotic schwannoma, but no psammomatous bodies were identified. Endocrine evaluation showed that this patient's symptoms fulfilled the diagnostic criteria of Carney complex, with lentiginosis, multiple breast ductal adenomas, multiple hypoechoic nodules on thyroid ultrasonography, and a 4 x 5-cm asymptomatic atrial cardiac myxoma, which was removed 15 days after the neurosurgery. Three months later, a recurrence of melanotic schwannoma was identified. Molecular analyses of genomic and somatic deoxyribonucleic acid from the patient found a 578 to 579delTG mutation of PRKAR1A. CONCLUSION: We present the unusual case of a nonpsammomatous trigeminal melanotic schwannoma associated with Carney complex, with confirmed PRKAR1A gene mutation. Our case highlights that neurosurgeons, in the presence of a melanotic schwannoma, should be aware of the features of the Carney complex because, in such cases, pre- and postoperative management is significantly affected. We also postulate that the absence of psammoma bodies or cranial localization do not exclude this diagnosis.

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Diversas mutações em oncogenes promovem o crescimento tumoral através da indução de atividade de proteínas que normalmente transmitem sinais proliferativos a partir de fatores extracelulares. As proteínas G são uma família de proteínas ligadas ao nucleotídeo guanina que apresentam homologia estrutural e estão amplamente distribuídas em células eucariotas. Elas são constituídas por três sub-unidades (alfa, beta e gama). A sub-unidade alfa apresenta o sítio de ligação ao nucleotídeo guanina e é única para cada proteína G. A proteínas G estão acopladas aos receptores de superfície celular com sete hélices transmembrana com uma grande variedade de efetores intracelulares e segundos mensageiros. Um subgrupo de tumores endócrinos, incluindo os tumores hipofisários secretores de GH e ACTH, nódulos tireoideanos autônomos, tumores adrenocorticais e gonadais, foram associados a mutações somáticas ativadoras em códons altamente conservados das proteínas Gs (Arg201 e Gln227) e Gi (Arg179, Gln205). Estes achados moleculares indicaram que as proteínas G atuam como oncogenes, contribuindo no processo da tumorigênese endócrina em humanos.

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