Notably, a recent study measured the level of three APO-E peptides (SELEEQLTPVAEETR, LGPLVEQGR, and AATVGSLAGQPLQER) in meningioma CSF samples, and the results indicated a 2.21-fold increase in APO-E in Grade 2 as compared to Grade 1 meningiomas [142]. The gene discussed is APOE; the disease is meningioma.