NCL was significantly downregulated in the adult brain, with 16% of the CD31+ cells being NCL+ ECs (predominant nucleolar expression) (Figure 1, E and Q), but it was significantly upregulated in GBM ECs, where 67% of the CD31+ were NCL+ (nucleoplasm and nucleolar expression), similar to its expression in fetal brain (Figure 1, D, F, and Q). This evidence concerns the gene PECAM1 and glioblastoma.