INDUCTION OF ENDOGENOUS DIFFERENTIATION PATHWAYS REGULATES NEUROBLASTOMA AGGRESSIVENESS

GARDE, FEDERICO JULIÁN; PASTORE, CANDELA DIVA; MOSNA, MARÍA JIMENA; STINSON, MARCELO GABRIEL; PETRIZ OTAÑO, LUCÍA PAULA; DI BELLA, DANIELA JÉSICA; CARCAGNO, ABEL LUIS

Valparaíso

Congreso; LASDB 2024; 2024

LASDB

Neuroblastoma (NB) is the most common extracranial pediatric cancer, originating from cells of the sympathoadrenal lineage. ASCL1 is a critical transcription factor in this lineage's development whose expression should be embryonic and transient, however, it is overexpressed in NB and has been linked to a worse clinical prognosis. The aim was to investigate the consequences of its knockdown (KD) in NB cells. We conducted ASCL1 KD in SK-N-SH cells. Additionally, we analyzed publicly available single-cell RNA sequencing (scRNA-seq) data obtained from tumors of NB patients, to gain insights into the heterogeneity of NB. ASCL1 loss of function results in the induction of differentiation of these cells. NB cells lacking ASCL1 acquire neuronal morphology and decrease their proliferative and migratory capacities, without affecting their viability. For our scRNA-seq analysis, we integrated the data into a single dataset, and clustered by dimensional reduction. We characterized the derived clusters by performing functional enrichment analysis and evaluating the expression patterns of ASCL1 with non-negative matrix factorization. Our findings revealed that NB cells share a common origin, specifically deriving from sympathoblasts of the adrenal medulla and that the observed heterogeneity can be explained by the grade of cellular differentiation and the predicted phase of the cell cycle. We discovered that ASCL1 is expressed across various clusters, and co-expresses with genes linked to neurogenesis and cell cycle. Finally, for future testing of ASCL1 KD, we optimized the implantation of SK-N-SH spheroids onto the chorioallantoic membrane of chicken.The results obtained led to two significant points: a) ASCL1 plays a role in blocking terminal neuronal differentiation in NB, thereby promoting tumor progression; b) the observed effects of reducing ASCL1 function in vitro that correlate with the role assessed in silico suggest that ASCL1 is a potential target for NB therapy.