OGDH and central nervous system cancer: Consistently, IF staining results showed that the IDH1 mutation significantly decreased 5-hmC levels in OGDH-silenced glioma cells (Fig. 6h), and immunoblotting data showed that the IDH1 mutation significantly elevated H3K27me3 and H3K4me3 levels in the OGDH-silenced U87 cells (Fig. 6i).