PRMT2 links histone H3R8 asymmetric dimethylation to oncogenic activation and tumorigenesis of glioblastoma

Here we show that PRMT2 is highly expressed in GBM, which is correlated with poor prognosis. The silencing of PRMT2 inhibits GBM cell growth and glioblastoma stem cell self-renewal in vitro and suppreses orthotopic tumor growth. Transcriptome analysis demonstrated that PRMT2 depletion leads to significant deregulation of genes mainly associated with cell cycle progression and pathways in cancer. In agreement with previously published results, we show that PRMT2 is responsible for H3R8 asymmetric methylation (H3R8me2a) and that H3R8me2a enrichment at promoters and enhancers is closely correlated with known active histone marks. Furthermore, we show that PRMT2-mediated H3R8me2a is required for the maintenance of target gene expression and that the catalytic activity of PRMT2 is required for its protumorigenic functions. Taken together, this study demonstrates that PRMT2 acts as a transcriptional co-activator for oncogenic gene expression programs in GBM pathogenesis and provides a rationale for PRMT2 targeting in aggressive gliomas. Overall design: To examine changes in histone-modification profiles and gene expression after knockdown of PRMT2 in human U87 cells or human primary glioblastoma cells TPC1115.