Fig. (4).

A). The activity of mTOR was measured by its ability to phosphorylated 4E-BP. The bottom band is the unphosphorylated form. 4E-BP. 4E-BP has multiple phosphrylation which depict multiple bands seen. After treatment with ADI-PEG at 0.6 ug/ml (81 IU/ml=11.3 mg/ml) for 72 hr., the major form of 4E-BP are unphosphorylated. B). phosphoryltion of p-70S6 kinase also reflect mTOR activity. After exposure to ADI-PEG20 at 0.6 mg/ml, the phospho-p-70S6 kinase decresaed in A-375, Sk-Mel2, but increase in A-2058, which indicative of phosphorylation from other upstream protein. Mel-1220 has minimal phosphorylation of p-70S6 kinase and hence changes is not discernable. C). phospho-AMPK in 4 melanoma cell lines after exposure to ADI-PEG20 for 72 ht. Three cell lines has increased phospho-AMPK, but no changes in Sk-Mel 2.