5'-Methylthioadenosine (MTA) can affect cellular processes in many ways. 5'-Methylthioadenosine has been shown to influence numerous critical responses of the cell including regulation of gene expression, proliferation, differentiation and apoptosis. Although most of these responses have been observed at the pharmacological level, their specificity makes it tempting to speculate that endogenous 5'-Methylthioadenosine could play a regulatory role in the cell. Finally, observations carried out in models of liver damage and cancer demonstrate a therapeutic potential for 5'-Methylthioadenosine that deserves further consideration ^{[1] .}