BCAM and medulloblastoma: PGE2 was secreted at substantial levels in vitro by one ependymoma and one medulloblastoma culture, and secretion was considerably reduced upon treatment with the selective COX-2 inhibitor Valdecoxib (Fig. 5c; AA-LU 74, p = 0.25; AEP-LU 158, p = 0.13; MB-LU 159, p = 0.25 by Wilcoxon matched pairs test).