RESUMEN
Malignant mesothelioma (MM) is an aggressive serosal tumor associated with asbestos exposure. We previously demonstrated that mesothelial cells differentiate into cells of different mesenchymal lineages and hypothesize that osseous tissue observed in a subset of MM patients is due to local differentiation of MM cells. In this study, the capacity of human and mouse MM cells to differentiate into osteoblast-like cells was determined in vitro using a functional model of bone nodule formation and in vivo using an established model of MM. Human and murine MM cell lines cultured in osteogenic medium expressed alkaline phosphatase and formed mineralized bone-like nodules. Several human and mouse MM cell lines also expressed a number of osteoblast phenotype markers, including runt-related transcription factor 2 (RUNX2), osteopontin, osteonectin and bone sialoprotein mRNA and protein. Histological analysis of murine MM tumors identified areas of ossification within the tumor, similar to those observed in human MM biopsies. These data demonstrate the ability of MM to differentiate into another mesenchymal cell type and suggest that MM cells may contribute to the formation of the heterologous elements observed in MM tumors.
Asunto(s)
Biomarcadores/metabolismo , Neoplasias Pulmonares/metabolismo , Mesotelioma/metabolismo , Osteoblastos/citología , Osteogénesis , Adulto , Fosfatasa Alcalina/metabolismo , Animales , Diferenciación Celular , Línea Celular Tumoral , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Dexametasona/farmacología , Dexametasona/uso terapéutico , Femenino , Humanos , Sialoproteína de Unión a Integrina/genética , Sialoproteína de Unión a Integrina/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Mesotelioma/tratamiento farmacológico , Mesotelioma/genética , Mesotelioma Maligno , Ratones , Trasplante de Neoplasias , Osteoblastos/metabolismo , Osteogénesis/efectos de los fármacos , Osteonectina/metabolismoRESUMEN
Pleural infection is a disease of historical importance and is still a modern menace, with incidences rising in adults and children, and a significant mortality in adults. Basic research is hampered by limitations with in vivo models, and the bacteriology of empyema is complex. The role of thoracic ultrasound in guiding investigation and drainage of empyema is clear. Prompt treatment with appropriate systemic antibiotics and chest tube drainage are the key; in cases of failure of these measures, thoracic surgery is of proven efficacy in the treatment of this age-old disease.
Asunto(s)
Antibacterianos/uso terapéutico , Infecciones Bacterianas , Empiema Pleural , Animales , Infecciones Bacterianas/complicaciones , Infecciones Bacterianas/tratamiento farmacológico , Infecciones Bacterianas/epidemiología , Tubos Torácicos , Drenaje , Empiema Pleural/tratamiento farmacológico , Empiema Pleural/epidemiología , Empiema Pleural/microbiología , Humanos , PrevalenciaRESUMEN
Bichat first described the mesothelium in 1827 but despite its early discovery, it has only been in recent years that its importance both in health and disease has been realised. One area still poorly understood is that of the mechanisms regulating mesothelial repair. Mesothelial cells are derived from the mesoderm but express many epithelial characteristics. However, mesothelium does not heal in the same way as other epithelial-like cells. Epithelium heals by centripetal migration, with cells at the edge of the wound proliferating and migrating into the injured area. Hertzler in 1919 noted that both large and small peritoneal injuries healed within the same time frame, concluding that the mesothelium could not heal solely by centripetal migration. The exact mechanisms involved in mesothelial regeneration following injury are controversial with a number of proposals suggested to explain the origin of the regenerating cells. This review will examine these proposals and give some insights into the likely mechanisms involved.