TP53 and multiple system atrophy: 25 proteins with at least 2.0-fold upregulation and 16 proteins with less than 0.5-fold downregulation in MSA-P cell lines revealed alterations in neuronal functions such as amplification and attenuation of electrical stimulus transmission, postsynaptic processes, mitochondrial processes, gene regulatory mechanisms, enzymatic processes, apoptosis, signal pathways, etc. As potential upstream regulators, chaperone, histone, histone demethylase and p53 protein were predicted.