RESUMEN
PURPOSE: To determine, by means of immunohistochemistry, tumoral expression of collagenase-3, a matrix metalloproteinase linked to cancer and to basal cell and squamous cell carcinomas of the eyelid. MATERIAL AND METHOD: Retrospective review of 23 basal cell carcinomas and 25 squamous cell carcinomas of the eyelid treated at different hospitals during the last five years. We evaluated collagenase-3 expression and the possible relationship to patient and tumour characteristics which included age, sex, histological type, tumour location and surgical margins status. RESULTS: 65% of the basal cell carcinomas and 88% of the squamous cell carcinomas of the eyelids stained positively for collagenase-3. In both cases, the immunostaining was localized in the cytoplasm of the malignant cells and, occasionally in the surrounding stromal cells. CONCLUSIONS: Statistical analysis showed no significant association between collagenase-3 immunostaining and patients or tumour characteristics but the expression of this protein was more intense in the epithelial tumoral cells located at the invading front which could explain the aggressive behaviour of this kind of tumours.
Asunto(s)
Carcinoma Basocelular/enzimología , Carcinoma de Células Escamosas/enzimología , Colagenasas/biosíntesis , Neoplasias de los Párpados/enzimología , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Basocelular/patología , Carcinoma de Células Escamosas/patología , Neoplasias de los Párpados/patología , Femenino , Humanos , Masculino , Metaloproteinasa 13 de la Matriz , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
The present study was designed to establish a) whether chromaffin cells of the human adrenal medulla express immunoreactivity for beta-amyloid precursor protein (beta APP) and/or beta-amyloid protein (beta/A4); and b) whether cells expressing one or both of the above-mentioned proteins display immunoreactivity for the low- (gp75) and/or the high-affinity (gp140-trkA) nerve growth factor receptor. To identify chromaffin cells and their supporting cells, chromogranin A, neurofilament proteins, and S-100 protein were studied in parallel. Beta APP and beta/A4 immunoreactivity (IR) was observed primarily labeling two different cell populations, without colocalization: Beta APP IR was found in the adrenal cortical cells, which were mainly localized in the reticulate layer and in the blood vessel walls, whereas beta/A4 IR was observed in the chromaffin cells. Furthermore, supporting cells were also immunoreactive for beta/A4, and sympathetic ganglionic cells were immunoreactive for both beta APP and beta/A4. Interestingly, clusters of cells expressing beta/A4 IR also displayed gp 75 IR and/or gp140-trkA IR. Finally, all chromaffin cells (identified by chromogranin A IR) were immunolabeled for the 200 kDa neurofilament subunit, but not for a phosphorylated epitope of this protein. These results demonstrate the occurrence of beta/A4 IR, but not of beta APP, in the chromaffin cells of the human adrenal gland. The complementary distribution of amyloid-related proteins, and the possible involvement of neurotrophins in beta/A4 metabolism are discussed.
Asunto(s)
Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Sistema Cromafín/metabolismo , Anciano , Sistema Cromafín/citología , Cromogranina A , Cromograninas/metabolismo , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Proteínas de Neurofilamentos/biosíntesis , Neuronas/metabolismo , Receptores de Factor de Crecimiento Nervioso/metabolismo , Proteínas S100/metabolismoRESUMEN
The distribution of the beta-amyloid precursor protein (betaAPP) in the human gastrointestinal tract, from esophagus trough rectum, was studied using immunoblotting, as well as combined immunohistochemical and image analysis (optic microdensitometry) techniques. The study was focused on the enteric nervous system. betaAPP was detected by means of a monoclonal antibody (22C11), which recognizes all betaAPP isoforms as well as betaAPP-like proteins. Immunoblotting revealed two main protein bands, one corresponding to full-length betaAPPs (estimated molecular masses of approximately 97-115 kDa); the other corresponded to a protein with estimated molecular masses of 55 kDa. Specific betaAPP immunoreactivity (IR) was found in the submucous and myenteric plexuses localized in the supporting glial cells rather than in neurons. Differences were encountered neither in the localization nor in the intensity of immunostaining among different segments of the gastrointestinal tract. Moreover, no age-dependent changes were found. betaAPP IR was also regularly observed in blood vessels, primarily labelling endothelial cells. Our results provide evidence for the occurrence of betaAPP in human gastrointestinal tract of healthy people in both neuronal and nonneuronal tissues. Whether or not these findings have functional or clinical relevance remains to be clarified in future studies.