Invasion (a), motility (b) and proliferation (c) of parental, vector, and siRNAi-vector transfected cells. The percentages of invading (t=24 hours) and migrating (t=24 hours) cells were calculated as reported in Materials and Methods. The pictures highlighted the differences in number between HepG2, pS, and pS-c-Myc cells able to invade (a) or migrate (b) to the lower surface of transwells. RNAi directed against c-Myc led to a reduced cellular growth rate after 24, 48 and 72 hours. Columns, averages of three independent experiments; error bars, SD. *P <0.05.