The National Cancer Institute (NCI) awarded a 5-year, $754,304 Project Grant (CFDA 93.393 - Cancer Cause and Prevention Research) to St. Jude Children's Research Hospital Inc. to examine the trajectory of epigenetic aging and health outcomes in childhood cancer survivors. The project will leverage the rich resources of the St. Jude Lifetime Cohort Study, which includes over 4,200 long-term childhood cancer survivors with detailed health data and epigenetic profiles. Key objectives are to: 1) assess the impact of health behaviors and social determinants on the rate of epigenetic age acceleration; 2) evaluate the association between epigenetic aging trajectories and long-term chronic health conditions and mortality; and 3) determine the effects of behavioral interventions on changes in epigenetic age. The findings will advance understanding of accelerated aging in childhood cancer survivors and guide the development of interventions to prevent or mitigate age-related health issues in this population.