Poor Diet Quality is Associated with Premature Senescence of the Immune System in Survivors of Childhood Acute Lymphoblastic Leukaemia.

Acute lymphoblastic leukemia (ALL) is the most common pediatric cancer. Contributory factors such as inflammation and oxidative stress, in response to drug therapies, may induce premature aging and cellular senescence with a severe impact on cardiometabolic health. Premature immunoaging through cellular senescence can lead to lower thymic output of T-cell lymphocytes translated into lower circulating T-cell receptor excision circles (TRECs). We hypothesized TRECs levels are associated with diet quality and impacted by oxidative and inflammatory status in survivors of childhood ALL (cALL). Adolescents and young adults cALL survivors from the PETALE cohort (n = 241, 22.1 ± 6.3 years at diagnosis, 49.4% males) were assessed for TREC levels and adherence to six diet quality indexes. Healthy Diet Indicator (HDI) was associated with TREC levels (β = 50.0, p = 0.005, adjusted p = 0.03). Interleukin-6 (IL-6) and C-reactive protein (CRP) were found negatively associated with TREC levels (β = -80 and -80.1, p = 0.017 and 0.026, respectively) HDI. Further analysis revealed IL-6 and CRP to be moderating factors, but not mediators, of the association between HDI and TRECs. This study supports a positive impact of a healthy diet on premature aging of the immune system in survivors of cALL and unveils the moderating role of inflammation in this association.