Moreover, PAK1 over-expression in MCF7 and T47D cells significantly enhanced invasion, mimicking the acquired invasive phenotype of FAR models, as revealed by the number of invading cells able to penetrate matrigel matrix in transwell inserts and by tumor spheroids invading area measured in a collagen type I matrix (Supplementary Fig. 4a, b; Fig. 3c, d). This evidence concerns the gene PAK1 and neoplasm.