Previous studies have shown a functional relationship between EF1α expression and invasion; in particular, expression of EF1α2 appears to increase cell migration, EF1α mRNA levels correlate with increased metastatic potential in mammary adenocarcinoma and EF1α protein is overexpressed in metastatic compared to non metastatic cells [16,19,31] However, Kulkarni et al. [18] reported that EF1α2 expression is associated with good prognosis and suggested that EF1α2 may not be able to activate an effective metastatic program. This evidence concerns the gene EEF1A1 and breast adenocarcinoma.