The effect of in vivo growth hormone treatment on blood gene expression in adults with growth hormone deficiency reveals potential biomarkers to monitor growth hormone therapy.

OBJECTIVE: Growth hormone (GH) replacement therapy is presently utilized in the treatment of adult GH deficiency (AGHD). Adult responses to GH treatment are highly variable and, apart from measurement of IGF-I, few tools are currently available for monitoring GH treatment progress. As GH receptors are expressed in certain blood cell types, changes in gene expression in peripheral blood can reflect perturbations induced as a result of GH therapy. DESIGN/PATIENTS: We have carried out a pilot study to identify GH-responsive genes in blood, and have assessed the utility of GH-responsive genes in monitoring GH therapy in AGHD. Blood was collected from ten women diagnosed with AGHD syndrome both before and 4 weeks after initiation of GH substitutive therapy. RNA was extracted from peripheral blood mononuclear cells (PBMCs) and changes in response to GH were detected using microarray-based gene analysis. RESULTS: All patients responded to GH replacement therapy, with serum levels of IGF-I increasing by an average of 307% (P = 0.0003) while IGFBP-3 increased by an average of 182% (P = 0.0002). Serum levels of triglycerides, LDL-C, HDL-C, APOA1 or APOB did not change after 1 month of GH treatment. By contrast, we detected an increase in Lp(a) serum levels (P = 0.0149). Using a stringent selection cutoff of P

Ezrin mediates c-Myc actions in prostate cancer cell invasion.

The forced overexpression of c-Myc in mouse prostate and in normal human prostate epithelial cells results in tumor transformation with an invasive phenotype. How c-Myc regulates cell invasion is poorly understood. In this study, we have investigated the interplay of c-Myc and androgens in the regulation of prostate cancer cell invasion. We found that c-Myc induces cell invasion and anchorage-independent growth by regulating ezrin protein expression in the presence of androgens. The activity of the ezrin promoter is controlled by androgens through c-Myc, which binds to a phylogenetically conserved E-Box located in the proximal promoter region. Besides, we also show that ezrin is an important regulator of c-Myc protein levels. These effects are achieved through androgen-induced changes in ezrin phosphorylation, which results in the regulation of downstream signals. These downstream signals involve the modulation of Akt and GSK-3beta activity resulting in increased c-Myc protein synthesis and inhibition of its degradation. In summary, we have shown a key role for ezrin as a mediator of c-Myc-induced tumorigenesis in prostate cancer cells.

Manejo de la taquicardia supraventricular paroxística en el primer mes de vida / Management of paroxysmal supraventricular tachycardia in the first month of life

Introducción: La taquicardia supraventricular paroxística(TSVP) es la arritmia más frecuente en Pediatríapor detrás de las extrasístoles. La mayoría de las veces esbien tolerada, pero hay que tener presente que existe riesgode insuficiencia cardiaca si la taquicardia se prolongaen el tiempo, por lo que es importante conocer la clínica,diagnóstico, y el manejo agudo y crónico de estos pacientes.Casos clínicos: Presentamos cuatro casos de TSVP enlactantes menores de un mes que han sido tratados en nuestrocentro en los últimos cuatro años. En nuestra serie no seobserva predominio de sexo, todos los casos ocurrieron antesdel mes de vida, dos de ellos se asociaron a cardiopatía congénita,uno presentó insuficiencia cardiaca y, tras la instauracióndel tratamiento crónico, ninguno ha presentado recurrenciashasta el momento actual.Comentarios: Aunque los trastornos del ritmo son relativamenteinfrecuentes en niños, su conocimiento es untema fundamental en la práctica pediátrica. Asimismo, esmuy útil disponer en nuestros servicios de protocolos deactuación unificados para el tratamiento de estos trastornos (AU)

Introduction: Paroxysmal supraventricular tachycardia(PSVT) is the most frequent arrhythmia in pediatrics afterextrasystoles. Most of the times, it is well tolerated, but itmust be kept in mind that there is risk of heart failure if thetachycardia is prolonged over time. Thus, it is important toknow the symptoms, diagnosis and acute and chronic managementof these patients.Clinical cases:We present four cases of PSVT in infantsunder one month who have been treated in our center overthe last 4 years. In our series, predominance of gender hasnot been observed. All the cases occurred prior to 1 monthsof life, two of which were associated to congenital heart diseaseand one had heart failure. After chronic treatment wasestablished, there have been no recurrences up to date.Comments: Although rhythm disorders are relatively rarein children, its knowledge is a fundamental subject in the pediatricpractice. In addition, it is very useful to have unified actionprotocols in our services for the treatment of these disorders (AU)

Asociación entre gastroenteritis aguda leve y convulsiones afebriles benignas / Association between mild acute gastroenteritis and benign afebrile convulsions

Introducción: La presentación de convulsiones benignas febriles durante una gastroenteritis leve sin deshidratación ni fiebre ni alteraciones electrolíticas es una asociación descrita con relativa frecuencia en Asia, siendo más desconocida fuera del continente asiático. Casos clínicos: Se describen las características de cuatro casos de lactantes que ingresaron en nuestro hospital por presentar convulsiones a febriles asociadas a gastroenteritis agudas. En tres de los cuatro casos se identificó la presencia de Rotavirus en heces y en todos los casos la evolución ha sido favorable. Comentarios: Probablemente, esta entidad es infradiagnosticada en nuestro país. Reconocer esta entidad debe servirnos para evitar tratamientos antiepilépticos prolongadose intensos (AU)

Introduction: The presentation of benign seizures afebriles in association a slight gastroenteritis without dehydration or fever or electrolytic imbalance is an association described with relative frequency in Asia, not being more known out of the Asian continent. Case reports: There are described the characteristics off our cases who joined our hospital for presenting convulsions afebriles associated with gastroenteritis acute. In three of four cases Rotavirus’s presence was identified in dregs and in all the cases the evolution has been favorable. Conclusions: Probably this entity is infradiagnosticada in our country. To recognize ourselves this entity must serve to avoid anti-epileptic long and intense (AU)

Gene polymorphisms in TYMS, MTHFR, p53 and MDR1 as risk factors for breast cancer: a case-control study.

Breast cancer (BC) is a complex disease influenced by environmental and genetic factors. The disease has important genetic and environmental components, most of them are still unknown. An important role of gene polymorphisms related to the risk of developing BC has been reported. However, the results have been controversial. We investigated the association of TSER, MTHFR C677T, p53 codon 72 and MDR1 C3435T gene polymorphisms with breast carcinoma in women from Canary Islands (Spain). Blood samples collected from 135 patients with BC and 304 healthy controls all of them Caucasian, were analyzed through polymerase chain reaction-restriction fragment length polymorphism. Subsequently, a structured questionnaire including patient history and risk factors in relation to BC development was filled out. Allelic frequencies of these genetic variations were: TSER, (2) 0.55 and (3) 0.45 in cases, 0.49 and 0.51 respectively in controls (P=0.240); MTHFR C677T, (C) 0.63 and (T) 0.37 in cases, 0.60 and 0.40 respectively in controls (P=0.568); p53 Arg72Pro, (Arg) 0.74 and (Pro) 0.26 in cases and controls (P=0.910); MDR1 C3435T, (C) 0.52 and (T) 0.48 in cases, 0.55 and 0.45 respectively in controls (P=0.523). We did not observe any gene polymorphism as a risk factor to develop BC. A statistical association was observed between p53 codon 72 polymorphism and family history of breast cancer in both groups, as well as between MDR1 C3435T and smoking habits in cases (P<0.05). Gene polymorphisms vary by regions. The present study contributes to the characterization of the genetic pattern of the Canary population.

Del laboratorio a la clínica: desarrollo de perfiles genéticos en cáncer de mama / No disponible

El cáncer de mama es una enfermedad con un alto impactoen nuestra sociedad. La incidencia y prevalencia de esta patologíaes cada vez mayor. En su desarrollo intervienen factoresgenéticos, epigenéticos y ambientales. Aún hoy se desconocenla totalidad de procesos involucrados en el desarrollo, promocióny progresión del tumor mamario. Por todo ello, los esfuerzosen investigación dentro de este campo son cada díamayores. El objetivo no es sólo entender el comportamientotumoral. Además se busca poder predecir el pronóstico, la respuestaa los tratamientos quimioterápicos y aumentar lo máximolos ratios de supervivencia. En la última década se ha desarrolladoy perfeccionado la tecnología de DNA microarray,que permite realizar estudios genéticos y genómicos a gran escala.La aplicación de esta técnica al campo de la oncología hagenerado muchos conocimientos y suscitado mucha expectación.En esta revisión hemos hecho una aproximación técnicaa la metodología de DNA microarray: sus principios básicos,en qué consiste, cómo interpretar los resultados, así como lasdiferentes estrategias que se pueden aplicar para visualizar,agrupar y comprender la inmensa cantidad de información generadacon este tipo de experimentos. Este trabajo incluye unestudio detallado de las aplicaciones que tiene el DNA microarrayen el cáncer de mama: estudios para mejorar el diagnóstico,para conocer mejor el pronóstico, para predecir la respuestaa los tratamientos, para identificar dianas terapéuticasy para generar test de diagnóstico clínico. Todas estas estrategiasbuscan llevar la metodología de DNA microarray del laboratorioa la práctica clínica rutinaria(AU)

Breast cancer is a disease with a profound impact in our society.Incidence and prevalence of this pathology increaseevery year. In the breast cancer developmet genetic, epigeneticand environmental factors are involved. Many details of theentire process of initiation, promotion and tumoral progressionare still unknown, and additional efforts are required. Themain objective is not only to understand the tumour behaviourbut also predict the prognosis, the response to quimiotherapictreatments and increase the survival ratios are importantgoals. In the last ten years DNA microarray technology hasbeen developed and improved. This is a high through puttechnology that permits genetic and genomic studies on alarge scale. The implementation of DNA microarray in oncologyhas been generated a big amount of knowledge as well asa great expectancy. In this review we have carried out a technicalapproximation to DNA microarray methodology: basicprinciples, how to interpret the results as well as the differentstrategies available for visualize, cluster and understand thevast amount of information generated with this kind of experiments.We have described in detail the applications of DNAmicroarray to breast cancer: studies for improve the diagnosis,to predict the prognosis and the response to quimiotherapy,to identify therapeutic targets and for to generate predictivetest useful in the clinical practice. All these strategies are oftranslational meaning, trying to carry the DNA microarrayfrom the laboratory to the daily clinical routine(AU)

Steroid binding sites in liver membranes: interplay between glucocorticoids, sex steroids, and pituitary hormones.

Steroid hormones activate target cells through specific receptors that discriminate among ligands based upon recognition of distinct structural features. For most known steroids, membrane and nuclear receptors co-exist in many target cells. However, while the structure of the nuclear receptors and their function as transcriptional activators of specific target genes is generally well understood, the identity of the membrane receptors remains elusive. Using pharmacological and biochemical approaches, we are beginning to characterize receptors for glucocorticoids and anabolic-androgenic steroids in male rat liver membranes. Male rat liver endoplasmic reticulum contains two steroid binding sites which are functionally related and associated with a 90-134 kDa oligomeric protein: (1) the low-affinity glucocorticoid binding site (LAGS), composed at least in part of two peptides (37 and 53 kDa) that bind glucocorticoids and (2) the stanozolol binding protein (STBP), composed at least in part of three peptides (22, 31, and 55 kDa) that bind the synthetic androgen stanozolol. These steroid binding proteins have many properties different from those of classical nuclear receptors, with the salient differences being a failure to recognize "classical" ligands for nuclear receptors together with marked differences in biochemical properties and physiological regulation. The mechanism of interaction of glucocorticoids with the LAGS can be clearly distinguished from that with STBP. Moreover, STBP shows an extremely narrow pharmacological profile, being selective for ST and its analog, danazol, among more than 100 steroids and non-steroidal compounds that were assayed, including those that are able to displace glucocorticoids from the LAGS. The level of LAGS activity undergoes dramatic variations following changes from the physiological serum levels of thyroid hormones, glucocorticoids, GH, vitamin A, and E2. However, neither thyroid hormones nor GH have a critical role on STBP activity. The STBP is functionally related to LAGS. We have suggested a novel mechanism for STBP whereby membrane-associated glucocorticoid binding activity is targeted by stanozolol (and 16beta-hydroxylated stanozolol): stanozolol modulates glucocorticoid activity in the liver through negative allosteric modulation of the LAGS resulting in an effective increase in classical GR-signaling by increasing glucocorticoid availability to the cytosolic GR.

IGF-II regulates metastatic properties of choriocarcinoma cells through the activation of the insulin receptor.

Choriocarcinoma is a highly malignant tumor that can arise from trophoblasts of any type of gestational event but most often from complete hydatidiform mole. IGF-II plays a fundamental role in placental development and may play a role in gestational trophoblastic diseases. Several studies have shown that IGF-II is expressed at high levels in hydatidiform moles and choriocarcinoma tissues; however, conflicting data exist on how IGF-II regulates the behaviour of choriocarcinoma cells. The purpose of this study was to determine the contribution of the receptors for IGF-I and insulin to the actions of IGF-II on the regulation of choriocarcinoma cells metastasis. An Immuno Radio Metric Assay was used to analyse the circulating and tissue levels of IGF-I and IGF-II in 24 cases of hydatidiform mole, two cases of choriocarcinoma and eight cases of spontaneous abortion at the same gestational age. The JEG-3 choriocarcinoma cell line was used to investigate the role of IGF-II in the regulation of cell invasion. We found that mole and choriocarcinoma tissue express high levels of IGF-II compared to first trimester placenta. Both IGF-I and IGF-II regulate choriocarcinoma cell invasion in a dose dependent manner but through a different mechanism. IGF-II effects involve the activation of the InsR while IGF-I uses the IGF-IR. The positive effects of IGF-II on invasion are the result of enhanced cell adhesion and chemotaxis (specifically towards collagen IV). The actions of IGF-II but not those of IGF-I were sensitive to inhibition by the insulin receptor inhibitor HNMPA(AM)3. Our results demonstrate that the insulin receptor regulates choriocarcinoma cell invasion.

Role of pituitary hormones on 17alpha-ethinylestradiol-induced cholestasis in rat.

Estrogens cause intrahepatic cholestasis in susceptible women during pregnancy, after administration of oral contraceptives, or during postmenopausal hormone replacement therapy. 17alpha-Ethinylestradiol (EE) is a synthetic estrogen widely used to cause experimental cholestasis in rodents with the aim of examining molecular mechanisms involved in this disease. EE actions on the liver are thought to be mediated by estrogen receptor alpha (ERalpha) and pituitary hormones. We tested this hypothesis by analyzing metabolic changes induced by EE in livers from hypophysectomized (HYPOX) and hypothyroid rats. Microarray studies revealed that the number of genes regulated by EE was increased almost 4-fold in HYPOX rat livers compared with intact males. Little overlap was apparent between the effects of EE in intact and HYPOX rats, demonstrating that pituitary hormones play a critical role in the hepatic effects of EE. Consistently, hypophysectomy protects the liver against induction by EE of serum bilirubin and alkaline phosphatase, two markers of cholestasis and hepatotoxicity and modulates the effects of EE on several genes involved in bile acid homeostasis (e.g., FXR, SHP, BSEP, and Cyp8b1). Finally, we demonstrate a novel mechanism of action of EE through binding and negative regulation of glucocorticoid receptor-mediated transcription. In summary, pituitary- and ERalpha-independent mechanisms contribute to development of EE-induced changes in liver transcriptome. Such mechanisms may be relevant when this model of EE-induced cholestasis is evaluated. The observation that the pharmacological effects of estrogen in liver differ in the absence or presence of the pituitary could be clinically relevant, because different drugs that block actions of pituitary hormones are now available.