Ribosome biogenesis is a therapeutic vulnerability in pediatric neuroblastoma

Abstract

Neuroblastoma is a heterogeneous malignant pediatric tumor, the prognosis of which depends on patient age and disease stage. Current treatment strategies rely on four key diagnostic criteria: age, histological stage, genomic profile, and MYCN gene status. The oncogenic activity of MYC depends on ribosome biogenesis, which is hyperactivated in cancer cells to support their high proliferative capacity, and which may thus represent a vulnerability in neuroblastoma and constitute a therapeutic target. Here, using the well-established IMR-32 cell line along with a previously established panel of patient-derived neuroblastoma cell lines with varying MYCN status, we show that RNA polymerase I inhibition following exposure to CX-5461 and BMH-21 suppressed cell proliferation at nanomolar concentrations and induced ribosomal stress, leading to the activation of apoptosis and the p21 pathway. Furthermore, analysis of expression of ribosome biogenesis factors using publicly available datasets and RT-qPCR data from an in-house neuroblastoma cohort, we identified FBL as a marker of poor prognosis in neuroblastoma. Consistently, FBL knockdown reduced neuroblastoma cell proliferation, supporting its relevance as a therapeutic target. In conclusion, our study reinforces the therapeutic potential of ribosome biogenesis inhibition in neuroblastoma and expands the list of potential targets to include rRNA maturation factors. These findings highlight the relevance of targeting ribosome biogenesis as a novel approach for neuroblastoma treatment.

Keywords: Cancer; Fibrillarin; MYC; Neuroblastoma; RNA polymerase I inhibitor; Ribosome biogenesis; Targeted therapy.