Despite their different cellular origins, statistically significant positive correlations were observed between the expression levels of DJ-1, GDF15, and MFGE8 and both tumour grade and the Ki-67 proliferation index (Ki-67 Pi) in both glioma and meningioma cases, indicating that higher gene expression is associated with increased tumour aggressiveness in both tumour types. This evidence concerns the gene GDF15 and central nervous system cancer.