To determine whether NHERF1 can be used as a diagnostic marker of ependymal tumors, a multi-institutional effort assembled a total of 113 primary brain tumors consisting of ependymomas, anaplastic ependymomas, and lower grade ependymal tumors, as well as miscellaneous other tumors considered in the differential diagnosis (Table 1). Here, NHERF1 is linked to ependymoma.