AARS1-mediated AKR1B10 lactylation stabilizes an aerobic glycolysis-positive feedback loop to drive lenvatinib resistance in hepatocellular carcinoma.

[BACKGROUND] Lenvatinib resistance (LR) represents a significant obstacle in hepatocellular carcinoma (HCC) treatment. Aldo-keto reductase family 1 member B10 (AKR1B10) is involved in tumour metabolic reprogramming; however, its role in LR remains unclear.

[METHODS] Bioinformatics analyses of public databases were integrated and validated in established LR HCC cell lines. Functional assays (CCK-8, flow cytometry and Seahorse XF analysis) were performed to assess proliferation, apoptosis and aerobic glycolysis. Post-translational modifications of AKR1B10 were characterized using co-immunoprecipitation, mass spectrometry and western blot.

[RESULTS] AKR1B10 was identified as a critical driver of resistance by establishing a metabolic positive feedback loop. Bioinformatics analyses and experimental validation demonstrated that AKR1B10 upregulation correlates with therapeutic resistance. Functional studies indicated that AKR1B10 promotes resistance by enhancing aerobic glycolysis. Mechanistically, alanyl-tRNA synthetase 1 mediates lactylation modification at AKR1B10 lysine 173 (K173), stabilizing AKR1B10 by blocking ubiquitin (Ub)-proteasomal degradation. Stabilized AKR1B10 interacts physically with lactate dehydrogenase A (LDHA), promoting LDHA phosphorylation at Y10 and accelerating glycolytic lactate production. The increased lactate subsequently induces histone H3K18 lactylation (H3K18la), which transcriptionally upregulates LDHA expression. Thus, a self-reinforcing AKR1B10-lactate-LDHA amplification circuit is formed. Clinical analyses confirmed elevated AKR1B10 expression in LR HCC patient tissues. Importantly, targeting this axis with the AKR1B10 inhibitor epalrestat (EPA) synergized with lenvatinib, overcoming resistance in xenograft mouse models and patient-derived xenograft models.

[CONCLUSIONS] These findings establish AKR1B10 as both a biomarker and a therapeutic target in HCC. They reveal a novel lactylation-driven glycolytic adaptation mechanism and support the clinical translation of combined EPA-lenvatinib therapy.

[KEY POINTS] AKR1B10 confers lenvatinib resistance by enhancing aerobic glycolysis in HCC cells. AKR1B10 undergoes AARS1-mediated lactylation at K173, stabilizing it by antagonizing ubiquitin-proteasomal degradation. AKR1B10 promotes LDHA Y10 phosphorylation, boosting lactate production, which drives H3K18la-mediated transcriptional upregulation of LDHA, creating a feed-forward loop. Targeting AKR1B10 with epalrestat synergizes with lenvatinib to overcome resistance in preclinical models.