Metabolomic Profiling of Asparaginase-Induced Hepatotoxicity in Pediatric Acute Lymphoblastic Leukemia

Asparaginase is an integral component in treating pediatric patients with acute lymphoblastic leukemia (ALL) and has improved overall survival. Hepatotoxicity is one of the most frequent dose-limiting toxicities of asparaginase, often resulting in early interruption of treatment and delayed subsequent cycles of therapy, compromising treatment outcomes (PMID 32275469). Hispanic children are at higher risk of developing ALL (PMID: 25953979), and asparaginase-related hepatotoxicity (PMID: 35658244). Hispanic patients are also at higher risk of developing metabolic disorders such as obesity and fatty liver disease (PMID: 29450072). We hypothesized that profiling the metabolome of pediatric patients with ALL, post-asparaginase treatment could reveal the metabolomic changes associated with hepatotoxicity and explore potential differences between Hispanic and non-Hispanic. To this end, we performed an untargeted metabolomics analysis on buffy coat samples of blood collected at remission from 60 patients treated with asparaginase. The study primarily aimed to compare metabolite profiles between those who developed hepatotoxicity (30 patients, including 50% Hispanics) and those who did not. Toxicity and ethnic differences were evaluated using a two-way ANCOVA, controlling for gender, BMI, and age, with significance set at a p-value ≤ 0.05.

In our analysis, we identified 843 biochemicals, including 92 unknown and 751 known compounds—comprising 144 amino acids (19.2%), 17 peptides (2.3%), 37 carbohydrates (4.9%), 9 energy sources (1.2%), 392 lipids (52.2%), 39 nucleotides (5.2%), 19 cofactors and vitamins (2.5%), 81 xenobiotics (10.8%), and 13 partially characterized molecules (1.7%). Of these, 47 metabolites showed significant alterations between patients with and without hepatotoxicity. Notably, taurocholenate sulfate, a bile acid metabolite, was significantly elevated in patients who developed hepatotoxicity (fold change: 1.97, p-value: 0.035), while the phosphatidylethanolamine metabolite 1-oleoyl-2-docosahexaenoyl-GPE (18:1/22:6) was markedly reduced (fold change: 0.47, p-value: 0.017). In our dichotomized analysis comparing Hispanics and non-Hispanics, we identified fifty-nine metabolites that showed significant differences in those who developed hepatotoxicity versus those who did not among non-Hispanics, with 31 of these metabolites overlapping with the whole cohort analysis. Notably, octadecadienedioate (C18:2-DC), a fatty acid metabolite, was the most elevated, while spermidine, a polyamine metabolite, was the most decreased in non-Hispanics with hepatotoxicity (fold change: 2.84 and 0.41; p-value: 0.027 and 0.004, respectively). Among Hispanics, eight unique metabolites were significantly altered, with 2-methylserine being the most elevated and pyrraline the most decreased in patients with hepatotoxicity compared to those without (fold change: 2.36 and 0.52; p-value: 0.049 and 0.035, respectively). In comparing metabolomic profiles between Hispanic and non-Hispanic pediatric patients with hepatotoxicity, we identified thirty-six significantly altered metabolites. Notably, asparagine, an amino acid metabolite, was significantly elevated in Hispanic (fold change: 5.72; p-value: 0.048), while methyl-4-hydroxybenzoate sulfate, a xenobiotic metabolite, was markedly reduced (fold change: 0.18; p-value: 0.019). In addition, several acylcarnitine (propionylcarnitine, acetylcarnitine, myristoylcarnitine, cerotoylcarnitine, palmitoleoylcarnitine, linoleoylcarnitine, linolenoylcarnitine, dihomo-linoleoylcarnitine, arachidonoylcarnitine, dihomo-linolenoylcarnitine) were elevated in Hispanics compared with non-Hispanics (1.57 - 2.25 fold, P <0.05). These findings suggest that Hispanic patients exhibit a distinct metabolic profile, providing insights into their heightened risk of asparaginase-related hepatotoxicity.

Our study is the first to map the metabolomic landscape linked to asparaginase-related hepatotoxicity in pediatric ALL patients, including an examination of ethnic disparities. Insights from future research into the mechanisms of asparaginase-induced hepatotoxicity, guided by our metabolomic findings, will enable the development of precise strategies to predict, manage, and alleviate adverse effects, thereby improving patient safety and the efficacy of treatments.