Knockdown of ribosomal protein S15A induces human glioblastoma cell apoptosis

BACKGROUND: RPS15A is a ribosome protein that is highly conserved in many organisms from yeast to human. A number of studies implied its role in promoting cancer cell growth. METHODS: Here, we firstly conducted RPS15A gene expression analysis in brain cancer using Oncomine database and found RPS15A was remarkably overexpressed in glioblastoma (GBM) compared with that in normal tissues. Then, the expression of RPS15A was specifically silenced in GBM cell line U251 using lentiviral-mediated RNA interference technique. We further investigated the effect of RPS15A knockdown in U251 cells using MTT assay, colony formation test, and flow cytometry analysis. We detected the protein level of Bcl-2 and poly (ADP-ribose) polymerase (PARP) as well as activation of caspase-3. RESULTS: Our results showed that the knockdown of RPS15A could inhibit cancer cell growth and colony formation in vitro, as well as induced cell cycle arrest at G0/G1 phase and cell apoptosis. In addition, Western blot analysis indicated that the knockdown of RPS15A could significantly inhibit bcl-2 and activate caspase-3 and PARP. CONCLUSIONS: Our findings suggest RPS15A may play an important role in the progression of GBM and lentiviral-mediated silencing of RPS15A could be an effective tool in GBM treatment.