Conversely, around 30% of proteins enriched in CSF-ICM were implicated in meningioma development or progression31, including the most common disease-monitoring markers in patients with meningioma APOA1, APOB, A1BG, HP, APCS and PDGFRB (Fig. 4d and Supplementary Table 5). Here, PDGFRB is linked to meningioma.