CSE1L在神经母细胞瘤发展中的作用及分子机制研究

神经母细胞瘤（Neuroblastoma, NB）是最常见儿童颅外恶性肿瘤，早诊困难、恶性度高、进展迅速，其发生发展的分子机制尚不明确。核转运因子染色体分离1样基因（Chromosome segregation 1-like, CSE1L）表达及定位异常与多种肿瘤的进展密切相关。本课题前期工作显示CSE1L可促进NB细胞增殖、减少细胞凋亡、加快细胞周期、细胞定位异常。本研究拟在NB细胞系和临床样本中观察CSE1L对细胞增殖、细胞周期、细胞凋亡、细胞转移等肿瘤进展指标的影响；利用裸鼠模型观察CSE1L对肿瘤形成作用，验证CSE1L参与调节NB肿瘤进展假说。采用ChIP-on-Chip、蛋白质亲和层析联合质谱、荧光素酶报告基因和ChIP-re-ChIP等方法揭示CSE1L调节NB进展机制。本课题的实施可阐明CSE1L对NB肿瘤进展作用及其分子调控机理，为NB临床诊治及预后提供新的分子标记物。

Neuroblastoma is the most common extra cranial solid tumor of childhood, with characters of difficult diagnosis, rapid progression and poor prognosis resulting in survival rates of less than 50%. The mechanisms of NB initiation and progression are still unclear. The cellular apoptosis susceptibility gene CSE1L (Chromosome segregation 1-like, CSE1L) is highly expressed in most cancers, although it was originally identified as a gene that renders cells vulnerable to apoptotic stimuli. Our previous work has shown that lentiviral knock-down of CSE1L in neuroblastoma cells inhibits cell proliferation, induces G2/M phase arrest and promotes apoptosis. Moreover, we found that CSE1L localizes in the nucleus of neuroblastoma cells rather than on the nuclear membrane in normal cells. These results suggest that CSE1L plays a role in regulation of neuroblastoma progression but the molecular mechanism remains to be fully elucidated. CSE1L is known to bind to select genes with significant functional consequences for p53-mediated transcription. Therefore, it is plausible that CSE1L involves in neuroblastoma progression via regulation of target gene's transcription as a co-factor. To investigate this hypothesis, human neuroblastoma cell lines and nude mice will be used to study the role of CSE1L in neuroblastoma proliferation and migration. Immunofluorescence and realtime-PCR will be performed in clinical samples of neuroblastoma to explore the relationship between expression level of CSE1L and tumor status (including gender, age, stage and metastis). Furthermore, ChIP-on-Chip, Affinity chromatography combined LC-MS/MS, Luciferase assay, ChIP-re-ChIP, Co-IP will be applied to investigate the molecular mechanism of CSE1L in regulation of candidate gene's transcription and expression. At the end of this study, we hope to uncover the molecular mechanism underlying the function of CSE1L for neuroblastoma progression, and provide evidence for CSE1L as a novel biomarker for diagnosis and prognosis in Neuroblastoma.