Eukaryotic translation initiation factor 3 subunit b is a novel oncogenic factor in prostate cancer.

Prostate cancer, the second most common cancer among male adults, affects millions globally. We sought to investigate the expression and contribution of Eukaryotic translation initiation factor 3 subunit b (EIF3B) in prostate cancer. Expression of EIF3B was analyzed in both human prostate patient tissues and prostate cancer cell lines. Small interfering RNA (siRNA) knockdown of EIF3B was introduced into prostate cancer cell line PC-3 and LNCaP, followed by examination of cell viability, proliferation and apoptosis using the MTT, cell counting and terminal deoxynucleotidyl transferase dUTP nick end labeling assays, respectively. An in vivo xenograft tumor mouse model was employed to address the role of EIF3B in tumorigenesis as well. Finally, a gene microarray analysis was performed to search for differentially expressed genes upon EIF3B knockdown. EIF3B was upregulated in prostate tumor tissues and prostate cancer cell lines. EIF3B knockdown inhibited viability and proliferation of prostate cancer cells, as well as promoted cell apoptosis. In the in vivo mouse model, inoculation of EIF3B knockdown PC-3 cells displayed inhibited growth of xenograft tumors. In addition, potential signaling pathways that might be involved in EIF3B action in prostate cancer were identified by the gene microarray. EIF3B is a novel oncogenic factor in prostate cancer both in vitro and in vivo, which could be employed as a novel therapeutic target in the treatment against prostate cancer.