SOX2 and neoplasm: The main findings of the present work can be summarized as follows: (i) the expression of the stemness marker SOX2 can be reliably assessed in meningioma by IHC, as this analysis closely reflects the level of SOX2 mRNA; (ii) SOX2 expression in meningioma is a biomarker of tumor aggressiveness; (iii) SOX2 expression is an intrinsic feature of meningiomas since first diagnosis without change through recurrences.