TBX3 and melanoma: Interestingly, TBX3 mRNA levels remained unaltered when the AKT pathway was inhibited with either AKTVIII or siAKT3 (Figures 3A, 3B) and pre-treatment of both melanoma cell lines with the proteasome inhibitor MG132 rescued TBX3 protein levels when the AKT pathway was inhibited (Figure 3C, 3D).