Deciphering the Role of Epigenetics in Osteosarcoma Progression: Pathways to Novel Therapeutics

Background: Osteosarcoma (OS) is a highly aggressive pediatric bone cancer with poor prognosis, especially in metastatic cases. Epigenetic modifications play a pivotal role in OS progression and metastasis. Objective: This study aims to investigate the role of epigenetic changes in OS and explore their potential as therapeutic targets for novel treatments. Method: A cohort of 112 OS patients from the Department of Orthopaedic Surgery, Rajshahi Medical College Hospital, was analyzed from June 2022 to June 2024. DNA methylation, histone modification, and microRNA expression profiles were assessed using PCR, chromatin immunoprecipitation, and RNA sequencing. The methylation status of tumor suppressor genes (p16INK4a, RASSF1A) was correlated with clinical outcomes. Data were analyzed using statistical methods, including Chi-square tests, logistic regression, and survival analysis. Results: Aberrant DNA methylation was observed in 67% of cases, with a significant association between methylation of p16INK4a and poor prognosis (p<0.01). Histone modification analysis revealed a 55% overexpression of histone deacetylases (HDACs) in OS tissues, correlating with high tumor grade (p<0.05). MicroRNA profiling showed that miR-21 was overexpressed in 72% of patients, while miR-34a was significantly downregulated in 58%. Logistic regression identified DNA methylation of p16INK4a as a key risk factor for metastasis (OR=2.3, 95% CI: 1.5–3.2). Kaplan-Meier survival analysis demonstrated that patients with hypermethylated p16INK4a had a significantly lower 5-year survival rate of 35%, compared to 60% in those with normal methylation patterns (p<0.01). A multivariate Cox regression model revealed that the combination of DNA methylation status and HDAC overexpression was an independent prognostic factor for worse overall survival (HR=2.5, 95% CI: 1.8–3.4). Conclusions: Epigenetic alterations, including DNA methylation, histone modification, and microRNA dysregulation, are critical in osteosarcoma progression. These findings support the potential of targeting epigenetic mechanisms for novel therapeutic strategies.