Abstract 445: Epigenetic modification induced by DNMTs inhibitor enhances apoptosis through p21 pathway in neuroblastoma cells

Abstract Introduction: Neuroblastoma, a prevalent and aggressive pediatric cancer, poses significant treatment challenges due to its aggressive nature, rapid proliferation, and tumor heterogeneity, particularly in high-risk cases. While genetic mutations and chromosomal abnormalities play a key role in the development and progression of neuroblastoma, there is growing evidence to confirm that epigenetic changes are equally important in influencing tumor behavior, treatment responses, and patient outcomes. Emerging evidence indicates that the DNMTs inhibitor (CM-272) may facilitate cell cycle arrest and induce apoptosis by modulating critical regulatory pathways. Therefore, our hypothesis is that CM-272 treatment could lead to apoptosis mediated cell death in SK-N-SH neuroblastoma cells through the upregulation of p21 transcription. Methods: To test our hypothesis, SK-N-SH cells were treated with 2 µM of CM-272 with untreated cells serving as control. Cell viability was evaluated using the Trypan Blue Dye Exclusion (TBDE) assay. Both qRT-PCR and western blot analyses were conducted to assess the expression levels of cell cycle, apoptotic, and epigenetic markers such as p53, p21, PARP, BAX, BCL-XL and DNMT1. The RT2 Profiler PCR array method was used for determining the expression profile of the cell cycle pathway genes. Results: Our study results confirmed that SK-N-SH cells treated with CM-272 undergo increased cell death. Consistent with our hypothesis, we observed an increase and decrease in BAX, BCL-XL levels, respectively, suggesting that DNMT1 inhibition might have facilitated the induction of apoptosis through a p21-driven mechanism. Conclusion: Our results highlight the potential use of CM-272 to induce apoptosis in SK-N-SH cells through p21 upregulation and an increase in BAX levels. Furthermore, our findings suggest that targeting DNMT1 may offer an alternative pathway for inducing cell death through elevation of p21 in neuroblastoma that may have p53 mutations. If validated in further studies, DNMTs-targeted therapies could represent a significant advancement in developing new treatments for aggressive cancers. Acknowledgements: This project was supported by the National Pediatric Cancer Foundation (NPCF). This research was also partially funded by the Bankhead Coley Infrastructure Development Grant from the Florida Department of Health that was awarded to A.R. through the Department of Pharmacology of the University of Miami (Coral Gables, Florida USA). The authors would like to thank Royal Dames of Cancer Research Inc. (Ft. Lauderdale, Florida) for their financial support in conducting this research. Citation Format: Arun Jagarlamudi, Nicolas Tapia Stoll, Shyam Sundar Jaganathan, Umamaheswari Natarajan, Appu Rathinavelu. Epigenetic modification induced by DNMTs inhibitor enhances apoptosis through p21 pathway in neuroblastoma cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 445.