KDM2B and neoplasm: Altogether, these results show that miR-M6-5p facilitates MDV latency by suppressing the expression of the viral lytic gene pp38 via targeting histone demethylase KDM2B accompanied by increased transcriptionally repressive histone marks H3K27me3 at the pp38 promoter, which can contribute to the second viral cytolytic replication and tumor formation in vivo.