NUCLEOLIN and neuroblastoma: In parallel, by Western blot analysis, we observed in Roniciclib treated NB cells a significant reduction of nucleolar proteins NCL and GPC2 and a less marked depletion for NPM1 and, particularly, for PES1, whose level remained almost unchanged, revealing the Roniciclib effect mainly with their translocation from nucleolus to nucleoplasm and cytoplasm (Fig. 7A, B).