Knockdown of eukaryotic translation initiation factors 3B (EIF3B) inhibits proliferation and promotes apoptosis in glioblastoma cells

Eukaryotic initiation factors 3 (EIF3) complex is essential for initiation of protein synthesis for both cells and virus. It consists of 13 subunits (EIF3A to M), among which EIF3B serves as a major scaffolding subunit. However, its functions in human glioblastoma have not been explored yet. Here, we showed that EIF3B was expressed in human glioblastoma (Grade I-IV) and human glioblastoma cell lines (U251, U87, A172 and U373). Loss of function analysis was performed on U87 cells using lentivirus-mediated siRNA against EIF3B. EIF3B-shRNA expressing lentivirus could effectively infect U87 glioma cells and downregulate EIF3B expression. Knockdown of EIF3B expression significantly inhibited proliferation of U87 cells. Further study showed that the proliferation inhibitory effect was associated with accumulation in G0/G1-phase cell number and an increased rate of apoptosis. In conclusion, EIF3B promotes the proliferation of U87 cells and may play an important role in human glioblastoma development.