A preclinical study using tazemetostat, a small-molecule inhibitor of EZH2, the catalytic subunit of PRC2, and an alternative EZH2 inhibitor, EPZ011989, showed a significant slowdown of tumor growth in one out of two cell line-derived xenografts (Fuji responding and HS-SY-II not responding) and in two out of three SyS PDX models (CTG-0771 and CTG-0331 responding, and CTG-1169 not responding), indicating a heterogenous behavior among SyS in vivo models to EZH2 inhibitors [76]. Here, EZH2 is linked to neoplasm.