Eight circRNAs, including circ_COL1A2, circ_PTN, circ_VCAN, circ_SMO, circ_PLOD2, circ_GLIS3, circ_EPHB4, and circ_CLIP2 showed significantly higher expression in glioblastoma (GBM) than in normal tissues [102]. This evidence concerns the gene PLOD2 and glioblastoma.