Potential role of WSB1 isoforms in growth and survival of neuroblastoma cells

WD repeat and SOCS box containing protein 1 (WSB1) generates three isoforms that were found to play a role in cancer cell growth and tumor progression. We have studied their expression in neuroblastoma (NB). The behavior of the expression levels of the WSB1 isoforms was analyzed in NB cell lines, in an in vivo NB xenograft mouse model, and in primary NB tumors using real-time PCR. Effective WSB1 small interfering RNAs were transfected into cultured NB cell lines, and cell viability was analyzed using XTT assay and flow cytometry. A significant predominance of the WSB1 isoform 3 (WSB13) expression level was demonstrated in all NB systems examined. Correspondingly, combination of WSB13 silencing together with WSB1 isoforms 1+2 silencing in NB cells showed reduced growth, enhanced apoptosis rate, and increased sensitivity to chemotherapeutic agents, specifically related to low expression of WSB13. Our results point to a possible differential role of WSB1 isoforms in NB and suggest WSB13 as a target for therapy in NB.