GDF15 and central nervous system cancer: In light of the growing significance of molecular biomarkers in central nervous system tumours, in this study, we aimed to comprehensively and quantitatively analyze the mRNA expression levels of DJ-1 (Parkinsonism-associated deglycase 7, PARK7), GDF15 (Growth Differentiation Factor 15), and MFGE8 (Milk Fat Globule-EGF Factor 8 Protein) in glioma and meningioma tissues and to thoroughly evaluate the associations between these gene expression profiles and clinicopathological parameters.