Epigenetic Upregulation of p21 via MDM2 and DNMT Inhibition Induces Cell Death in Neuroblastoma Cells

Epigenetic Upregulation of p21 via MDM2 and DNMT Inhibition Induces Cell Death in Neuroblastoma Cells

Alvin Sherman Library

Neuroblastoma is a childhood cancer that primarily impacts children, mostly under five years of age, that originates from neuroblast cells. It's located in the adrenal glands, neck, or thorax. Experimental evidence indicates that epigenetic modifications influencing cell cycle arrest and programmed cell death (PCD), including apoptosis, may provide an effective treatment strategy for enhancing neuroblastoma that is resistant to conventional therapies. This study explored MDM2 and DNMT pathways that might suppress DNA methylation leading to the upregulation of TET enzymes and p21, which trigger cell cycle arrest and apoptotic in IMR-32 cells were treated with RG-7388, CM-272, and SGI-1027 for 24 hours. qRT-PCR assay was performed to assess the gene expression level on DNMT-1, DNMT-3A, DNMT-3B, G9a, EZH2, TET-2, TET-3, MDM2, p53, p21, and PARP. Western blotting methods were employed to evaluate protein expression levels of biomarkers linked to epigenetic, cell cycle, and apoptosis. qRT-PCR revealed a reduction of DNMT-1, DNMT-2A, DNMT-3B, G9a, and EZH2 levels in the CM-272 and SGI-1027-treated cells when compared to the control. Western blot analysis demonstrated an increase in BAX after CM-272 treatment, decrease in DNMT-1, and cleavage of PARP (indicating apoptosis). The results indicate that CM-272 treatments effectively reduce methylation by suppression of DNMTs and promote p21 upregulation in IMR-32 cells, resulting in cell cycle arrest and apoptosis. These findings indicate that additional trials and understanding of these epigenetic modulators are necessary as potential therapeutic agents for treating neuroblastoma treatment.