Persson Paula, Manetopoulos Christina, Lagergren Anna, Nygren Jens, Gisler Ramiro, Axelson Håkan, Sigvardsson Mikael
Department of Laboratory Medicine, Division of Molecular Medicine, Lund University, University Hospital MAS, Malmö, Sweden.
Int J Cancer. 2004 May 20;110(1):22-30. doi: 10.1002/ijc.20092.
The childhood malignancy neuroblastoma is derived from developmentally arrested sympathetic nervous system precursor cells. To obtain further insight into the molecular processes involved in the formation of these tumors, we decided to investigate the functional role of Olf/EBF (O/E) transcription factors in human neuroblastoma cells. We here report that O/E-1 and O/E-2 are expressed at variable levels in neuroblastoma cell lines and that O/E proteins could be identified by electrophoretic mobility shift assays. To identify potential neuronal target genes for O/E proteins in neuroblastoma cells we investigated the ability of a set of neuronal promoters to interact with O/E-1 in electrophoretic mobility shift assays. This analysis suggested that the Chromogranin A (CgA) and SCG10 promoters both contained binding sites for O/E-1. O/E-1 was able to activate the CgA promoter in vivo and mutation of the O/E-1 binding site in the CgA promoter reduced the functional activity of the element to about 60% of the wild-type in neuroblastoma cells, supporting the idea that O/E proteins may be involved in the control of the CgA promoter. Furthermore, overexpression of O/E-1 in hippocampal progenitor cells led to neurite outgrowth, indicative of a role for O/E proteins in neuronal differentiation.
儿童恶性肿瘤神经母细胞瘤源自发育停滞的交感神经系统前体细胞。为了更深入了解这些肿瘤形成过程中涉及的分子机制，我们决定研究嗅觉/早期B细胞因子（O/E）转录因子在人神经母细胞瘤细胞中的功能作用。我们在此报告，O/E-1和O/E-2在神经母细胞瘤细胞系中以不同水平表达，并且可以通过电泳迁移率变动分析鉴定出O/E蛋白。为了在神经母细胞瘤细胞中鉴定O/E蛋白潜在的神经元靶基因，我们在电泳迁移率变动分析中研究了一组神经元启动子与O/E-1相互作用的能力。该分析表明，嗜铬粒蛋白A（CgA）和SCG10启动子均含有O/E-1的结合位点。O/E-1能够在体内激活CgA启动子，并且CgA启动子中O/E-1结合位点的突变将该元件的功能活性降低至神经母细胞瘤细胞中野生型的约60%，这支持了O/E蛋白可能参与CgA启动子调控的观点。此外，O/E-1在海马祖细胞中的过表达导致神经突生长，表明O/E蛋白在神经元分化中发挥作用。
