EuroClone S.p.A Research Laboratory, Molecular Biotechnology Centre-MBC, University of Turin, Turin, Italy.
PLoS One. 2013 May 24;8(5):e63748. doi: 10.1371/journal.pone.0063748. Print 2013.
Medulloblastoma (MB) is an aggressive pediatric tumor of the Central Nervous System (CNS) usually treated according to a refined risk stratification. The study of cancer stem cells (CSC) in MB is a promising approach aimed at finding new treatment strategies.
METHODOLOGY/PRINCIPAL FINDINGS: The CSC compartment was studied in three characterized MB cell lines (DAOY, UW228 and ONS-76) grown in standard adhesion as well as being grown as spheres, which enables expansion of the CSC population. MB cell lines, grown in adherence and as spheres, were subjected to morphologic analysis at the light and electron microscopic level, as well as cytofluorimetric determinations. Medullospheres (MBS) were shown to express increasingly immature features, along with the stem cells markers: CD133, Nestin and β-catenin. Proteomic analysis highlighted the differences between MB cell lines, demonstrating a unique protein profile for each cell line, and minor differences when grown as spheres. In MBS, MALDI-TOF also identified some proteins, that have been linked to tumor progression and resistance, such as Nucleophosmin (NPM). In addition, immunocytochemistry detected Sox-2 as a stemness marker of MBS, as well as confirming high NPM expression.
CONCLUSIONS/SIGNIFICANCE: Culture conditioning based on low attachment flasks and specialized medium may provide new data on the staminal compartment of CNS tumors, although a proteomic profile of CSC is still elusive for MB.
成神经管细胞瘤（MB）是一种侵袭性儿童中枢神经系统（CNS）肿瘤，通常根据精细的风险分层进行治疗。MB 中癌症干细胞（CSC）的研究是一种很有前途的方法，旨在寻找新的治疗策略。
方法/主要发现：在三种特征明确的 MB 细胞系（DAOY、UW228 和 ONS-76）中研究了 CSC 区室，这些细胞系在标准贴壁培养以及作为球体培养，这使 CSC 群体得以扩增。MB 细胞系在粘附和球体培养中，在光镜和电子显微镜水平以及细胞荧光测定中进行形态分析。髓质球体（MBS）表现出越来越不成熟的特征，同时表达干细胞标志物：CD133、Nestin 和β-catenin。蛋白质组学分析突出了 MB 细胞系之间的差异，证明每个细胞系都有独特的蛋白质谱，而作为球体培养时差异较小。在 MBS 中，MALDI-TOF 还鉴定出一些与肿瘤进展和耐药性相关的蛋白质，如核磷蛋白（NPM）。此外，免疫细胞化学检测到 Sox-2 作为 MBS 的干性标志物，并证实 NPM 表达较高。
结论/意义：基于低附着瓶和专用培养基的培养条件可能为 CNS 肿瘤的干细胞区室提供新的数据，尽管 MB 的 CSC 蛋白质组学图谱仍难以捉摸。
