“…In contrast, deacetylation of these residues is associated with a repressive state (Rice and Allis, 2001). Consequently, combinations of histone deacetylase inhibitors with hypomethylating agents results in reactivation of gene expression (Richon and O'Brien, 2002), cell cycle arrest and apoptosis (Zhu et al, 2001b;Tang et al, 2004;Schmelz et al, 2005;Walton et al, 2008). The azanucleosides analogs have also shown synergistic activity with conventional nucleoside analog chemotherapeutic agents such as 5-fluorouracil, which is based on their ability to reactivate previously silenced proapoptotic genes (Kanda et al, 2005;Morita et al, 2006).…”