Abstract 5215: Metabolic and lipidomic changes in early asparaginase hepatotoxicity in mice

Abstract Asparaginase (ASNase) is an effective treatment for pediatric acute lymphoblastic leukemia but is limited by hepatotoxicity, particularly in obese patients. While ASNase has been shown to induce adipocyte lipolysis and hepatocyte integrated stress response, the mechanisms by which ASNase causes hepatosteatosis and hepatotoxicity remain unclear. We previously examined the effects of PEG-ASNase on livers in mice seven days after injection. However, by this timepoint, livers were severely steatotic. Therefore, to uncover early effects of ASNase, we treated obese and control 18-week-old male C57Bl6 mice with one IP dose of 3,000 IU/kg pegylated-ASNase and analyzed livers three days later. ASNase caused significant hepatosteatosis already 3 days after injection (n=6; Table). ASNase increased liver unsaturated triglycerides and decreased phosphatidylcholine and lysophosphatidylcholine. Metabolomics identified decreases in s-adenylmethionine (SAM), 5-Aminoimidazole-4-carboxamide ribonucleoside (AICAR), and glutathione to glutathione disulfide ratio (GSH:GSSG, Table), indicating oxidative stress. These lipidomic and metabolomic changes were more pronounced in obese mice. RNAseq identified lower expression of palatin-like phospholipase domain containing protein 3 (PNPLA3) after ASNase (-4.8 to -5.1 log2fold change, p0.001). qPCR showed low PNPLA3 expression in obese compared to control vehicle livers (p0.001) and confirmed substantial suppression after ASNase in both groups (Table). Our results show that within three days, ASNase induces hepatic steatosis, oxidative stress lower phosphatidylcholine levels and suppression of PNPLA3 expression. These effects appear to be magnified in obesity. Since phosphatidylcholine and PNPLA3 are known to be related to metabolic dysfunction associated steatotic liver disease (MASLD), these effects are likely contributory to ASNase hepatotoxicity. Further work is needed to fully understand the mechanisms of these changes. Citation Format: Veronica Ruiz-Torres, Jennifer J. Chia, Michael D. Cohen, Jia Tan, Kevin J. Williams, Nedas Matulionis, Abby Krall, Heather R. Christofk, Etan Orgel, Steven D. Mittelman. Metabolic and lipidomic changes in early asparaginase hepatotoxicity in mice abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 5215.