YTHDF1 and oligoastrocytoma: The expression of YTHDF1 was proportional to the brain tumor grade with the statistical significance of GBM vs. oligodendroglioma p = 0.0001, GBM vs. oligoastrocytoma p = 0.001, and GBM vs. astrocytoma p = 0.04 (Fig. 7a, left panel).