Integrative network toxicology reveals lipoprotein lipase as a key mediator of dibutyl phthalate-associated head and neck squamous cell carcinoma

Dibutyl phthalate (DBP) is a widely distributed endocrine-disrupting chemical with potential carcinogenic properties, yet its role in head and neck squamous cell carcinoma (HNSC) remains unclear. Here, we applied an integrative framework combining network toxicology, Mendelian randomization (MR), multi-omics analyses, molecular docking, molecular dynamics simulations, and in vitro experiments to elucidate the mechanisms underlying DBP-associated HNSC. Lipoprotein Lipase (LPL) was identified as the sole overlapping gene between DBP-related targets and HNSC-associated genes. MR analysis supported a potential causal relationship between LPL and HNSC susceptibility. Expression profiling demonstrated tissue- and cell type-specific patterns of LPL and its dysregulation in HNSC, with associations to tumor stage and prognosis. Genomic analyses revealed that LPL alterations were infrequent and mainly driven by copy number loss. LPL expression positively correlated with immune and stromal infiltration. Enrichment analyses implicated immune regulation and PI3K-AKT signaling. Molecular simulations showed stable DBP-LPL binding. Functionally, DBP promoted SCC9 proliferation and reduced LPL expression, and was associated with transcriptional changes in PI3K-AKT-mTOR-related genes, whereas LPL restoration mitigated these effects. These findings reveal a novel DBP-LPL axis in HNSC.