Decrease in neuron-restrictive silencer factor (NRSF) mRNA levels during differentiation of cultured neuroblastoma cells

Non-neuronal cells and undifferentiated neuronal progenitors express the neuron-restrictive silencer factor (NRSF), a silencer protein which represses neuronal gene transcription in these cell types. Neuroblastoma, a childhood tumor of neuroectodermal origin, shares some biological properties with neuronal progenitor cells and can acquire neuronal phenotypes in response to a variety of agents, including cyclic AMP and staurosporine. We report here that NRSF mRNA content was markedly decreased in a human neuroblastoma cell line following differentiation induced by staurosporine plus cyclic AMP, with a concomitant increase in mRNA levels of synapsin I, whose expression is restricted to neuronal cell types. Our novel finding suggests that NRSF expression is related to an undifferentiated state and regarded as a biochemical marker of neuronal differentiation in neuroblastoma cells.