Trojanowski J Q, Tohyama T, Lee V M
Department of Pathology, University of Pennsylvania School of Medicine, Philadelphia 19104-4283.
Mol Chem Neuropathol. 1992 Oct;17(2):121-35. doi: 10.1007/BF03159987.
We review here recent data that have brought into sharper focus a number of important biological properties of the neoplastic cells in childhood primitive neuroectodermal tumors (PNETs) of the central nervous system (CNS). Studies of this group of tumors, as exemplified by posterior fossa medulloblastomas (MBs), suggest that neoplastic cells in PNETs partially recapitulate stages in the maturation of normal human neuroblasts. These findings may contribute to the elucidation of the mechanisms involved in tumor initiation and progression because oncogenes and antioncogenes appear to exert their effects in a cell type-specific manner that also depends on the maturational state of a given cell. Currently, a large body of data suggests that populations of cells in PNETs (e.g., MBs) exhibit one or more molecular defects in the sequence of maturational events leading to the exit of stem cells or partially committed neuron-like precursors from the cell cycle, followed by their terminal differentiation into neurons. This, together with the orchestrated interactions of as yet unidentified oncogenes and antioncogenes in these PNET cells, may represent a cluster of molecular abnormalities that underly the emergence of the highly malignant phenotype that characterizes childhood PNETs.
我们在此回顾近期的数据，这些数据使中枢神经系统（CNS）儿童原始神经外胚层肿瘤（PNET）中肿瘤细胞的一些重要生物学特性更加清晰地显现出来。以颅后窝髓母细胞瘤（MB）为例，对这组肿瘤的研究表明，PNET中的肿瘤细胞部分重现了正常人神经母细胞成熟过程中的阶段。这些发现可能有助于阐明肿瘤发生和进展所涉及的机制，因为癌基因和抗癌基因似乎以细胞类型特异性的方式发挥作用，这也取决于特定细胞的成熟状态。目前，大量数据表明，PNET（如MB）中的细胞群体在导致干细胞或部分定向的神经元样前体细胞退出细胞周期，随后终末分化为神经元的成熟事件序列中表现出一种或多种分子缺陷。这与这些PNET细胞中尚未确定的癌基因和抗癌基因的精心编排的相互作用一起，可能代表了一系列分子异常，这些异常是儿童PNET高度恶性表型出现的基础。
