Growth-mode-independent glutamine/glutamate/aspartate metabolic shift and urea cycle remodeling driven by FOXA1 in benzo[a]pyrene-transformed human bronchial epithelial cells

To characterize the amino acid metabolic remodeling in THBEc1 cells malignantly transformed by benzo[a]pyrene (BaP) relative to parental human bronchial epithelial HBE cells, and to delineate the role of FOXA1 in this remodeling, the amino acid metabolic phenotypes and gene expression patterns of HBE, THBEc1, THBEc1-ctrl (knockout control), and THBEc1-FOXA1 KO (FOXA1 knockout) cells were profiled under 2D, 3D spheroid, and in vivo conditions. Differential metabolic amino acids across these growth modes were identified. THBEc1 cells exhibited a glutamine/glutamate/aspartate metabolic shift and urea cycle remodeling that were conserved across all growth modes, representing key metabolic features of BaP-induced malignant transformation. FOXA1 knockout partially reversed these metabolic alterations across growth modes. Mechanistically, FOXA1 transcriptionally regulated GLUL, SLC6A14, CPS1, and SLC7A2 in a growth-mode-independent manner. These findings establish FOXA1 as a key mediator of the glutamine/glutamate/aspartate metabolic shift and urea cycle remodeling during BaP-induced malignant transformation, with GLUL, SLC6A14, CPS1, and SLC7A2 as critical downstream targets. This work advances the understanding of amino acid metabolic reprogramming in BaP-induced lung carcinogenesis.