Department of Pathology, Medical School, University of Valencia/INCLIVA, Valencia, Spain.
CIBERONC, Madrid, Spain.
J Exp Clin Cancer Res. 2020 Oct 28;39(1):226. doi: 10.1186/s13046-020-01729-1.
Increased tissue stiffness is a common feature of malignant solid tumors, often associated with metastasis and poor patient outcomes. Vitronectin, as an extracellular matrix anchorage glycoprotein related to a stiff matrix, is present in a particularly increased quantity and specific distribution in high-risk neuroblastoma. Furthermore, as cells can sense and transform the proprieties of the extracellular matrix into chemical signals through mechanotransduction, genotypic changes related to stiffness are possible.
We applied high density SNPa and NGS techniques to in vivo and in vitro models (orthotropic xenograft vitronectin knock-out mice and 3D bioprinted hydrogels with different stiffness) using two representative neuroblastoma cell lines (the MYCN-amplified SK-N-BE(2) and the ALK-mutated SH-SY5Y), to discern how tumor genomics patterns and clonal heterogeneity of the two cell lines are affected.
We describe a remarkable subclonal selection of genomic aberrations in SK-N-BE(2) cells grown in knock-out vitronectin xenograft mice that also emerged when cultured for long times in stiff hydrogels. In particular, we detected an enlarged subclonal cell population with chromosome 9 aberrations in both models. Similar abnormalities were found in human high-risk neuroblastoma with MYCN amplification. The genomics of the SH-SY5Y cell line remained stable when cultured in both models.
Focus on heterogeneous intratumor segmental chromosome aberrations and mutations, as a mirror image of tumor microenvironment, is a vital area of future research.
组织硬度增加是恶性实体瘤的常见特征，常与转移和患者预后不良相关。作为一种与坚硬基质相关的细胞外基质锚定糖蛋白，纤连蛋白在高危神经母细胞瘤中含量特别高且分布特定。此外，由于细胞可以通过力学转导将细胞外基质的特性感知并转化为化学信号，因此与硬度相关的基因型变化是可能的。
我们应用高密度 SNPa 和 NGS 技术，对体内和体外模型（异体移植纤连蛋白敲除小鼠和具有不同硬度的 3D 生物打印水凝胶）进行研究，使用两种代表性的神经母细胞瘤细胞系（MYCN 扩增的 SK-N-BE(2)和 ALK 突变的 SH-SY5Y），以辨别这两种细胞系的肿瘤基因组学模式和克隆异质性是如何受到影响的。
我们描述了在 SK-N-BE(2)细胞在敲除纤连蛋白的异种移植小鼠中生长时，以及在长时间培养于坚硬水凝胶中时，基因组中出现了显著的亚克隆选择的基因组异常。特别是，我们在两种模型中都检测到了带有 9 号染色体异常的扩大的亚克隆细胞群。在具有 MYCN 扩增的人类高危神经母细胞瘤中也发现了类似的异常。当在两种模型中培养时，SH-SY5Y 细胞系的基因组保持稳定。
关注肿瘤微环境的异质性肿瘤内部片段染色体异常和突变，是未来研究的重要领域。
