Considering that overexpression of EEF1D resulted in an increase in SIAH-1 level [30], and that Siah-1-interacting protein (CacyBP/SIP), a component of a novel ubiquitinylation pathway affects the proliferation of human glioma cells by regulating phospho-Akt (p-Akt) [31], we propose that EFF1D might regulate Akt-mTOR and Akt-Bad signaling pathways through interacting with SIAH-1. This evidence concerns the gene AKT1 and central nervous system cancer.