STAT3 and astrocytoma (excluding glioblastoma): STAT3 mRNA expression in WHO grade III gliomas (including anaplastic astrocytoma (AA), anaplastic oligodendroastrocytoma (AOA) and anaplastic oligodendroglioma (AO)) was higher than that in WHO grade II gliomas (including astrocytoma (A), oligodendroastrocytoma (OA), and oligodendroglioma (O)) (Figure 1C).