CDKN2B and mantle cell lymphoma: To understand how EZH2 confers growth advantage in the MCL cell lines, we focused on our attention to the cell cycle regulators, which are most commonly disrupted or deregulated either by homozygous deletion or epigenetic silencing via promoter hyper-methylation of cdkn2b (p15), and/or cdkn2a (p16) loci (37, 38).