# The Hypomethylating Agent 5-Azacitidine Potentiates the Effect of RAS and Sp1 Inhibitors in Neuroblastoma Cells

## TL;DR

This study shows that combining 5-azacitidine with RAS and Sp1 inhibitors enhances cell death in neuroblastoma cells, offering a potential new treatment strategy.

## Contribution

The study identifies synergistic drug combinations involving 5-azacitidine for neuroblastoma treatment.

## Key findings

- 5-azacitidine combined with mithramycin A and lonafarnib synergistically induced SH-SY5Y cell death.
- The drug combinations activated pathways for cell differentiation and apoptosis in neuroblastoma cells.
- Transcriptomic analysis revealed mechanisms of cell death and adaptation to hypomethylating agents.

## Abstract

Neuroblastoma is a malignant solid tumor caused by the transformation of neural
crest cells. Neuroblastoma predominantly occurs in children and is associated
with a poor prognosis. In this regard, the development of novel approaches to
neuroblastoma treatment, including combination therapy, is relevant. DNA
hypermethylation of neuroblastoma cells indicates that it is possible to use
hypomethylating agents in a combination therapy of the disease. In order to
identify effective combinations of antitumor drugs, we analyzed the
transcriptomic changes that take place in neuroblastoma SH-SY5Y cells after
treatment with the hypomethylating agent 5-azacitidine and then experimentally
tested the effectiveness of these combinations. Mithramycin A and lonafarnib
were the two drugs that, in combination with 5-azacitidine, appeared to exert a
synergistic effect on SH-SY5Y cell death. These drugs inhibit the signaling
pathway associated with the transcription factor Sp1 and RAS-MAPK signaling
pathway, which are activated by 5-azacitidine. An analysis of the signaling
pathways also revealed an activation of the signaling pathways associated with
neuroblastoma cell differentiation, as well as apoptosis induction, as
confirmed by multiplex and confocal microscopy. Hence, by analyzing the changes
in the signaling pathways, the mechanisms of cell death and cell adaptation to
hypomethylating agents can be understood, and this can be further used to
develop novel therapeutic approaches to neuroblastoma therapy.