In addition, in the UACC930 melanoma cell line, where the expression of GRM1 protein is not detectable [24], the induction of Smad2 and Smad3 linker phosphorylation in the presence of riluzole is comparable to that of the other melanoma cell lines that express GRM1 (Figures 3A and 3B). Here, SMAD3 is linked to melanoma.