To study the influence of Pak inhibition in cells lacking Merlin function, we established a stable NIH-3T3 fibroblast cell line overexpressing Merlin ΔBB, a mutant form of the tumor suppressor that lacks the “Blue Box” motif and which, in Drosophila, acts in a dominant negative fashion, in effect mimicking loss of the NF2 gene (Fig. 1A) [30]. The gene discussed is NF2; the disease is neoplasm.