EIF5A2, a downstream target of p-Akt, regulates melanoma cell invasion. (A) MMRU cells were transfected with vector control or EIF5A2 overexpression plasmid, or treated with 2.5 μM of either API1 or DMSO for 48 h. Protein extracts were prepared and analysed for the expression of EIF5A2, p-Akt and total Akt by western blot analysis. (B) Boyden chamber assay was performed 24 h after transfection or API1 treatment. *P<0.05, **P<0.01, Student's t-test. (C) Matrix metalloproteinase-2 activity determined by zymography, which was performed 48 h after transfection or API1 treatment. Recombinant MMP-2 was used as a positive control. (D) Positive staining of EIF5A2 directly correlates with strong expression of MMP-2 in human melanomas (n=369; P=0.0024, χ2-test). (E) MMRU cells were transfected with either siC plus empty vector or EIF5A2 overexpression plasmid, or a combination of EIF5A2 overexpression plasmid and siMMP-2. Boyden chamber assay was performed 48 h after transfection. **P<0.01, Student's t-test. (F) Positive staining of EIF5A2 directly correlates with strong expression of p-Akt in human melanomas (n=123, P=0.026, χ2-test).