Xenograft models of human neuroblastoma bone metastases.

描述（由申请人提供）： 神经母细胞瘤是一种神秘的肿瘤，其中一些患有广泛疾病的患者即使没有治疗也表现良好，而另一些患者尽管进行了清髓性治疗，但仍在不断进步。与神经母细胞瘤不良结局相关的一个关键临床特征是骨转移的存在。尽管骨转移与神经母细胞瘤的不良预后相关，并且骨病对临终痛苦有重要贡献，但关于神经母细胞瘤骨转移的生物学研究很少，也没有临床研究。我们建议利用我们的大型（> 200）人类神经母细胞瘤细胞系来鉴定细胞系，这些细胞系容易在免疫功能低下（SCID）小鼠的骨中形成转移。我们将采用高分辨率的小动物放射成像来监测动物的骨转移，并在尸检时确定用于直接组织病理学和细胞培养的部位。然后，我们建议在高度选择的一组细胞系中使用亲和寡核苷酸阵列基因表达谱（6个显示容易形成骨转移，6个在通过静脉注射到SCID小鼠中进行测试时不形成骨转移）来鉴定其中改变的表达（特别是过表达）与在SCID小鼠中形成骨转移的能力相关的基因。我们将通过重复循环的静脉注射到SCID小鼠中并收获和再培养发现在骨中生长的细胞来选择具有增加的形成骨转移的偏好的细胞，并且我们将使用Affytron表达谱将所选择的细胞系与原始亲本系以及不“归巢”于骨的细胞系进行比较。我们将通过定量RT-PCR对表达谱鉴定的基因进行分析，以证实基因过表达（或表达不足）与骨转移之间的关系。将对该组中已知形成或不形成骨转移的所有细胞系进行RT-PCR，还将使用来自小鼠骨的异种移植肿瘤进行RT-PCR，并与皮下或其他非骨部位生长的非骨转移性异种移植物进行比较。该项目将提供细胞系和动物模型，这将有助于了解神经母细胞瘤骨转移的生物学，也可用于临床前治疗研究。我们还将确定候选基因是关键的骨转移神经母细胞瘤。在未来的研究中，超出本提案的范围，我们和/或其他研究人员可以确定所鉴定的候选基因在通过转导过度表达时赋予SCID小鼠中形成骨转移的能力的能力，以已知很少形成骨转移的细胞系。这些候选基因可能适用于神经母细胞瘤以外的肿瘤。我们预计，该项目将增加我们对骨转移生物学的理解，并将开发小鼠模型，用于高风险神经母细胞瘤新治疗方法的临床前测试。

DESCRIPTION (provided by applicant): Neurobtastoma is an enigmatic tumor, in which some patients who have widespread disease do well, even with no therapy, while others relentlessly progress, in spite of myeloablative therapy. A key clinical feature associated with bad outcome in neurobtastoma is the presence of bone metastases. In spite of the association of bone metastases with poor outcome in neurobtastoma, and the important contribution that bony disease makes to end-of-life suffering, there have been a paucity of biological studies on neurobtastoma bone metastases, and no clinical tdals. We propose to utilize our large (> 200) panel of human neuroblastoma cell lines to identify cell lines, which readily form metastases in bones of immunocompromised (SCID) mice. We will employ high-resolution small animal radiographic imaging to monitor the animals for bone metastases, and to identify sites for directed histopathology and cell culture at the time of necropsy. We then propose to use Affymetrix otigonucleotide array gene expression profiling in a highly selected panel of cell lines (6 shown to readily form bone metastases and 6 that do not when tested by i.v. injection into SCID mice) to identify genes in which altered expression (especially over-expression) correlates with the ability to form bone metastases in SCID mice. We will select for cells with an increased predilection to form bone metastases by repeated cycles of intravenous injection into SCID mice and harvest and re-culture of cells found growing in bone, and we will compare the selected cell lines to the original parental lines, and to cell lines that do not "home" to bone, using Affymetrix expression profiling. We will confirm a relationship between gene over-expression (or under-expression) and bone metastases in our large panel of cell lines by quantitative RT-PCR for genes identified by expression profiling. RT-PCR will be conducted for all cell lines in the panel known to form or to not form bone metastases, and also will be conducted using xenograft tumors from mouse bone and compared to non-bone metastasizing xenografts grown subcutaneously or in other non-bony sites. This project will provide cell lines and animal models that will be useful for understanding the biology of bone metastases in neuroblastoma, and also for pre-clinical therapeutic studies. We will also identify candidate genes that are key for bone metastases in neuroblastoma. In future studies, beyond the scope of this proposal, we and/or other investigators can determine the ability of the identified candidate genes, when over expressed via transduction, to confer an ability to form bone metastases in SCID mice to cell lines known to rarely form bone metastases. Those candidate genes are likely to be applicable to tumors other than neuroblastoma. We anticipate that this project will increase our understanding of the biology of bone metastases and will develop mouse models for pre-clinical testing of new therapeutic approaches to high risk neuroblastoma.