We note that ectopic expression of ARMC12 rescues the decreased H3K27me3 enrichment on target gene promoters induced by EZH2 knockdown in NB cells, suggesting that the binding of AMRC12 to RBBP4 may result in structure alteration of PRC2 that facilitates the activity of EZH2 expressed at relatively low levels, which warrants further investigation. The gene discussed is RBBP4; the disease is neuroblastoma.