Expression of E-cadherin, Slug and NCAM and its relationship to tumor invasiveness in patients with acromegaly

Pituitary adenomas account for 10-15% of primary intracranial tumors. Growth hormone (GH)-secreting adenomas account for 13% of all pituitary adenomas and cause acromegaly. These tumors can be aggressive, invade surrounding structures and are highly recurrent. The objective of this study was to evaluate E-cadherin, Slug and neural cell adhesion molecule (NCAM) expression in GH-secreting pituitary adenomas and its relationship to tumor invasiveness. A cross-sectional study of patients who underwent hypophysectomy due to GH-secreting pituitary adenoma from April 2007 to December 2014 was carried out. The medical records were reviewed to collect clinical data. Immediately after surgery, tumor samples were frozen in liquid nitrogen and stored in a biofreezer at -80°C for assessment of E-cadherin 1 (CDH1), SLUG (SNAI2), and NCAM (NCAM1) by real-time PCR. The samples were fixed in formalin and embedded in paraffin for immunohistochemical analysis of E-cadherin and NCAM. Thirty-five patients with acromegaly were included in the study. Of these, 65.7% had invasive tumors. Immunohistochemically, E-cadherin was expressed in 96.7% of patients, and NCAM in 80% of patients. There was no statistically significant relationship between tumor grade or invasiveness and immunohistochemical expression of these markers. Regarding gene expression, 50% of cases expressed CDH1, none expressed SNAI2, and 53.3% expressed NCAM1. There was no statistically significant relationship between tumor grade or invasiveness and gene expression of CDH1, SNAI2, and NCAM1. The absence of Slug overexpression and of E-cadherin and NCAM suppression suggests that expression of these markers is not associated with tumor invasiveness in GH-secreting pituitary adenomas.

Estudio piloto de marcadores inflamatorios en el sindrome de apnea obstructiva del sueño / Pilot study of inflammatory markers in the syndrome of obstructive sleep apnea

El síndrome de Apnea Obstructiva del Sueño (SAOS), consiste en la aparición repetida de episodios de obstrucción faríngea durante el sueño como consecuencia de un colapso de la vía respiratoria. La respuesta fisiológica a la hipoxia intermitente crónica es la generación de una respuesta inflamatoria local y sistémica. Se han evidenciado cambios importantes a nivel cardiovascular en pacientes con SAOS; sin embargo, se desconocen cuáles marcadores séricos y genéticos pudieran ser de utilidad. En el presente estudio, se presentan 15 marcadores séricos y 3 genéticos (IL-6, IL-1β y TNF-α) en un grupo de cinco pacientes para determinar cuáles pueden ser los marcadores de interés en la aparición y en el desarrollo de esta patología respiratoria. Se proponen como marcadores los niveles séricos: proteína C reactiva, TNFα, IL-6, el receptor soluble de TNF I, sCD62, sCD154, nitrotirosina y anti-oxLDL. Los niveles de IL-1 β, el receptor de TNF soluble II, sCD25, sCD54, nitritos y nitratos no parecieran ser buenos marcadores en SAOS. Los estudios genéticos no fueron concluyentes.

Obstructive sleep apnea syndrome (OSAS) is a repeated sequences of pharynx obstruction during sleep as a consequence of airway collapse. The physiological response to the desaturation is the generation of a local and systemic inflammatory immune response. Important changes at cardiovascular levels in patients with OSAS have been observed; however, it is not know which serum or genetic parameters could be useful. In the present study, we present 15 serum and 3 genetic (IL-6, IL-1β y TNF-α) markers in a group of five patients in order to determine which marker could be useful to study the genesis and progression of this respiratory pathology. The proposed serum markers are C reactive proteín, TNFα, IL-6, soluble de TNF receptor I, sCD62, sCD154, nitrotirosine and anti-oxLDL. The levels of IL-1 β, soluble TNF receptor II, sCD25, sCD54, nitrite y nitrate do not seem to be good markers for OSAS. The genetic studies were not conclusive.

Morphometric Evaluation of PGP9.5 and NCAM Expressing Nerve Fibers in Colonic Muscle of Patients with Hirschsprung's Disease

A quantitative assessment of the density of the protein gene product 9.5 (PGP9.5), the neural cell adhesion molecule (NCAM), and the low-affinity nerve growth factor receptor (NGFR) expressing nerve fibers in the circular muscle layer in the colon was carried out by morphometric analyses from 13 patients with Hirschsprung's disease (HD). The difference in the nerve fiber density between the ganglionic and aganglionic segments was compared by calculating the ratio of the sum of the areas occupied by positively stained nerve fibers per unit area of the muscle after immunohistochemical staining on paraffin embedded tissue sections using computer software. There was an obvious difference in the density of the PGP9.5 stained nerve fibers between the ganglionic (0.0380 +/- 0.0171) and aganglionic segments (0.0143 +/- 0.01661). The NCAM-positive nerve fibers were fewer in number than those of both the PGP9.5-positive fibers and NCAM-positive fibers, which were also markedly lower in number in the aganglionic segment (0.0066 +/- 0.0076) than in the ganglionic segment (0.0230 +/- 0.0195). Immunostaining for low-affinity NGFR revealed much fainter staining in the ganglionic and aganglionic segment without a statistically significant difference in their density. Considering the fact that PGP9.5 is a very sensitive marker for nerve fibers, the results of this study reaffirm the innervation failure of the proper muscle in HD. The decreased NCAM expression level in the aganglionic segment appears to be caused not by the selective down-regulation of NCAM expression among the nerve fibers but by a markedly reduced number of nerve fibers.

The 9-O-acetyl GD3 gangliosides are expressed by migrating chains of subventricular zone neurons in vitro

Neurons from the anterior subventricular zone (SVZ) of the cerebral cortex migrate tangentially to become interneurons in the olfactory bulb during development and in adult rodents. This migration was defined as neuronophilic, independent of a radial glial substrate. The cortical SVZ and the rostral migratory stream to the olfactory bulb were shown to be rich in 9-O-acetyl GD3 gangliosides (9-O-acGD3), which have been previously shown to be implicated in gliophilic migration in the rodent cerebral cortex and cerebellum. In the present study, we performed SVZ explant cultures using rats during their first postnatal week to analyze the expression of these gangliosides in chain migration of neuronal precursors. We characterized migrating chains of these neuroblasts through morphological analysis and immunocytochemistry for the neural cell adhesion molecule. By using the Jones monoclonal antibody which binds specifically to 9-O-acGD3 we showed that migrating chains from the SVZ explants express 9-O-acGD3 which is distributed in a punctate manner in individual cells. 9-O-acGD3 is also present in migrating chains that form in the absence of radial glia, typical of the neuronophilic chain migration of the SVZ. Our data indicate that 9-O-acetylated gangliosides may participate in neuronophilic as well as gliophilic migration