Figure 3.

Methylthioadenosine (MTA) inhibits in vivo tumor growth and decreases the activation of RAS and PI3K tumor signaling pathways. (A) 37-31E melanoma cell line was subcutaneously injected into immunocompetent FVB/N mice. The animal groups were treated with DMSO (Control) (n = 7) or methylthioadenosine (MTA) (n = 7). Tumor size was calculated as described in materials and methods. p-values were calculated performing a t-student test. Representative photographs of three paired untreated and MTA-treated excised melanoma tumors are showed on the right. (B) Immunostaining of paraffin-embedded tumor sections showing the levels of p-Erk1/2, p-Akt and p-S6 (20×). Insets show a 40× detail of the picture. Representative images from two different untreated and treated tumors are shown.