倫敦大學瑪麗皇后學院的一項新的研究表明,，一種在兒童中常見的腦癌——髓母細胞瘤(medulloblastomas)發(fā)源于一種神經(jīng)干細胞。這篇研究報告發(fā)表在Oncogene雜志上,，研究表明,，這種癌癥可能需要一種有別于其他腫瘤治療的新的治療方法,。
在所有患腦部腫瘤的兒童中,，患髓母細胞瘤的可能性占1/5。這種腫瘤常發(fā)生于3～8歲的兒童中,，也偶發(fā)于年輕人中,。
之前曾有研究表明，人類大腦中存在一些神經(jīng)干細胞(neural stem cells),，能夠在一定程度上進行自我修復,。在最近的這項研究中，研究人員對小鼠大腦中的神經(jīng)干細胞進行研究,。
他們發(fā)現(xiàn)了兩個特殊的基因Rb 和p53,，在人類中，這兩個基因功能異常往往會導致癌癥的發(fā)生,，在老鼠中,，這兩個基因功能異常導致小鼠發(fā)生髓母細胞瘤。隨后,，研究人員進一步對髓母細胞瘤的遺傳組成進行研究,，通過對比人的髓母細胞瘤，他們發(fā)現(xiàn)了一種特殊的遺傳模式,，出現(xiàn)這種遺產(chǎn)模式的腫瘤患者生存機率很低,。（生物谷Bioon.com）
生物谷推薦原始出處：
Oncogene 11 January 2010; doi: 10.1038/onc.2009.472
Cerebellar stem cells act as medulloblastoma-initiating cells in a mouse model and a neural stem cell signature characterizes a subset of human medulloblastomas
R Sutter1, O Shakhova1, H Bhagat1, H Behesti1, C Sutter2, S Penkar1, A Santuccione2, R Bernays3, F L Heppner4,7, U Schüller5, M Grotzer6, H Moch2, P Schraml2 and S Marino1
1 Neuroscience Centre, Blizard Institute of Cell and Molecular Science, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
2 Institute of Surgical Pathology, Department of Pathology, University Hospital, Zürich, Switzerland
3 Department of Neurosurgery, University Hospital, Zürich, Switzerland
4 Institute of Neuropathology, Department of Pathology, University Hospital, Zürich, Switzerland
5 Center for Neuropathology, Ludwig-Maximilians-University, Munich, Germany
6 Department of Oncology, University Children's Hospital of Zurich, Zürich, Switzerland
Cells with stem cell properties have been isolated from various areas of the postnatal mammalian brain, most recently from the postnatal mouse cerebellum. We show here 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, injection of these cells into mice formed 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. Here, we describe 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.
