For this, 4-month-old tumor bearing-NPcis animals were treated with a c-Fos mRNA antisense oligonucleotide (ASO), the corresponding sense (or scrambled) oligo (SO) or vehicle infused intra-cranially by means of a subcutaneously implanted osmotic pump which was connected to a cannula inserted in the caudate putamen (CP) to constantly deliver treatment solution during 28 days. This evidence concerns the gene FOS and neoplasm.