Poluha W, Poluha D K, Ross A H
Worcester Foundation for Experimental Biology, Shrewsbury, Massachusetts 01545.
Oncogene. 1995 Jan 5;10(1):185-9.
We examined events associated with neuronal differentiation of neuroblastoma cell line SH-SY5Y. Treatment with nerve growth factor (NGF) and aphidicolin, an inhibitor of DNA polymerases alpha and delta, induces terminal differentiation of SH-SY5Y cells. Following 3-4 days of treatment with NGF + aphidicolin, the cells irreversibly ceased proliferation and differentiated. There was a succession of events preceding differentiation. Down-regulation of c-myc was an early event occurring after less than 1 day of treatment with NGF + aphidicolin. Upregulation of the trkA and low-affinity NGF receptors (LNGFR) occurred after 3 days of NGF + aphidicolin treatment and required treatment with both NGF and aphidicolin. To test the role of TrkA in neuroblastic differentiation, we transfected SH-SY5Y cells with a TrkA-expression plasmid. In response to NGF in the absence of aphidicolin, the TrkA-transformant line ceased proliferation and irreversibly differentiated. SH-SY5Y cells bearing a control plasmid displayed only modest, reversible differentiation and did not cease cell proliferation in response to NGF. Hence, expression of NGF receptors is upregulated during differentiation of SH-SY5Y cells, and overexpression of TrkA enhances NGF-induced differentiation.
我们研究了与神经母细胞瘤细胞系SH-SY5Y神经元分化相关的事件。用神经生长因子（NGF）和阿非迪霉素（一种DNA聚合酶α和δ的抑制剂）处理可诱导SH-SY5Y细胞的终末分化。在用NGF +阿非迪霉素处理3 - 4天后，细胞不可逆地停止增殖并分化。在分化之前有一系列事件发生。c-myc的下调是在用NGF +阿非迪霉素处理不到1天后发生的早期事件。trkA和低亲和力NGF受体（LNGFR）的上调在NGF +阿非迪霉素处理3天后出现，并且需要同时用NGF和阿非迪霉素处理。为了测试TrkA在神经母细胞分化中的作用，我们用TrkA表达质粒转染SH-SY5Y细胞。在没有阿非迪霉素的情况下，响应NGF，TrkA转化细胞系停止增殖并不可逆地分化。携带对照质粒的SH-SY5Y细胞仅表现出适度的、可逆的分化，并且在响应NGF时不会停止细胞增殖。因此，在SH-SY5Y细胞分化过程中NGF受体的表达上调，并且TrkA的过表达增强了NGF诱导的分化。
