When we calculated correlations between the mRNA expression levels of 31 genes associated with Wnt/β-catenin signaling and 8 immune cell fractions in GBM patients, only DKK3 showed statistically significant correlations (p < 0.001) with all 8 immune cell fractions (an x in the box indicates a p-value ≥ 0.001) (Fig. 2B). This evidence concerns the gene DKK3 and glioblastoma.