Here, we report that treatment of melanoma cells with GTPs reduces the melanoma cell viability and this effect of GTPs is mediated through, (i) inhibition of the levels of class I HADC proteins, (ii) inhibition of HDAC activity while enhancing HAT activity, (iii) DNA damage and (iv) suppression of cell cycle regulatory proteins of G1 phase. This evidence concerns the gene HDAC9 and melanoma.