Medulloblastomas come from stem cells
30 Janeiro 2010
A recent report published in Oncogene has shed new light to the origin on medulloblastomas, linking them to neural stem cells. Cells with stem cell properties have been isolated from various areas of
the postnatal mammalian brain, most recently from the postnatal mouse
cerebellum. A team from Switzerland and UK has showed that inactivation of the tumor suppressor genes
Rb and p53 in these endogenous neural stem cells induced deregulated proliferation and resistance to apoptosis in vitro.
Moreover, they have injected these cells into mice, forming medulloblastomas.
Medulloblastomas are the most common malignant brain tumors of
childhood, and despite recent advances in treatment they are associated
with high morbidity and mortality. They are highly heterogeneous tumors
characterized by a diverse genetic make-up and expression profile as
well as variable prognosis. The authors described a novel ontogenetic
pathway of medulloblastoma that significantly contributes to
understanding their heterogeneity. Experimental medulloblastomas
originating from neural stem cells preferentially expressed stem cell
markers Nestin, Sox2 and Sox9, which were not expressed in
medulloblastomas originating from granule-cell-restricted progenitors.
Furthermore, the expression of these markers identified a subset of
human medulloblastomas associated with a poorer clinical outcome.
the postnatal mammalian brain, most recently from the postnatal mouse
cerebellum. A team from Switzerland and UK has showed that inactivation of the tumor suppressor genes
Rb and p53 in these endogenous neural stem cells induced deregulated proliferation and resistance to apoptosis in vitro.
Moreover, they have injected these cells into mice, forming medulloblastomas.
Medulloblastomas are the most common malignant brain tumors of
childhood, and despite recent advances in treatment they are associated
with high morbidity and mortality. They are highly heterogeneous tumors
characterized by a diverse genetic make-up and expression profile as
well as variable prognosis. The authors described a novel ontogenetic
pathway of medulloblastoma that significantly contributes to
understanding their heterogeneity. Experimental medulloblastomas
originating from neural stem cells preferentially expressed stem cell
markers Nestin, Sox2 and Sox9, which were not expressed in
medulloblastomas originating from granule-cell-restricted progenitors.
Furthermore, the expression of these markers identified a subset of
human medulloblastomas associated with a poorer clinical outcome.