According to the proposed functions of the two classical RA signaling pathways [15] and our data from human medulloblastoma cells [13], it was possible that the distinct CRABP-II and FABP5 expression patterns found randomly in the four grades of astrocytomas might explain the variable RA sensitivities of individual glioblastoma cases. This evidence concerns the gene FABP5 and astrocytoma (excluding glioblastoma).