Spindle cell oncocytoma of the adenohypophysis in a woman: a case report and review of the literature

<p>Abstract</p> <p>Introduction</p> <p>Spindle cell oncocytoma of the adenohypophysis is a rare tumour recently reported by Roncaroli <it>et al. </it>in 2002. This tumour is considered a grade I tumour by the World Health Organization.</p> <p>Case presentation</p> <p>We describe what is, to the best of our knowledge, the 14th case of its kind in the literature. A 45-year-old African woman presented clinical and radiological findings related to a nonfunctioning pituitary adenoma. The diagnosis was made on the basis of histological and immunohistochemical findings.</p> <p>Conclusion</p> <p>The purpose of this work is to report a rare pituitary tumour and to describe its histological and immunohistochemical features, which were characterized by the expression of thyroid transcription factor 1 antigen by tumour cells. This fact could support the theory of a possible common origin of these tumours in pituicytomas. In fact, thyroid transcription factor 1 is considered to be a specific marker of pituicytes.</p

Mesenchymal differentiation of glioblastoma stem cells

Glioblastoma multiforme is a severe form of cancer most likely arising from the transformation of stem or progenitor cells resident in the brain. Although the tumorigenic population in glioblastoma is defined as composed by cancer stem cells (CSCs), the cellular target of the transformation hit remains to be identified. Glioma stem cells (SCs) are thought to have a differentiation potential restricted to the neural lineage. However, using orthotopic versus heterotopic xenograft models and in vitro differentiation assays, we found that a subset of glioblastomas contained CSCs with both neural and mesenchymal potential. Subcutaneous injection of CSCs or single CSC clones from two of seven patients produced tumor xenografts containing osteo-chondrogenic areas in the context of glioblastoma-like tumor lesions. Moreover, CSC clones from four of seven cases generated both neural and chondrogenic cells in vitro. Interestingly, mesenchymal differentiation of the tumor xenografts was associated with reduction of both growth rate and mitotic index. These findings suggest that in a subclass of glioblastomas the tumorigenic hit occurs on a multipotent stem cell, which may reveal its plasticity under specific environmental stimuli. The discovery of such biological properties might provide considerable information to the development of new therapeutic strategies aimed at forcing glioblastoma stem cell differentiation