Gadolinium nanoparticles on the AG matrix at a similar dose caused a decrease in the expression of bcl-2 in the rat brain [23], which is consistent with the results of Alarifi S. et al. (2017) on the suppression of the expression of Bcl-2 mRNA when exposed to nanoparticles of gadolinium oxide Gd2O3 on the culture of human neuroblastoma cells [30]. This evidence concerns the gene BCL2 and neuroblastoma.