1,4-dinitrosopiperazine specifically induces malignant nasopharyngeal transformation through the cytochrome P450 enzyme

1,4-Dinitrosopiperazine (DNP), a nitrite-derived compound widely found in Cantonese-style salted fish, induces malignant transformation of nasopharyngeal epithelial cells, but its tissue specificity and carcinogenic mechanisms remain unclear. In this study, tree shrews were used to investigate the tissue specificity and carcinogenic mechanisms of DNP. A pathological atlas of tree shrew nasopharyngeal tissue was constructed via anatomical and pathological examination. Pharmacokinetics and tissue affinity were assessed through single-dose administration, quantifying blood/tissue distribution via liquid chromatography-tandem mass spectrometry‌ (LC‒MS/MS). Chronic intervention was established via 12-month DNP exposure, with micro positron emission tomography/computed tomography (PET-CT) imaging and pathology confirming malignant transformation. Network toxicology analyzed DNP-associated head/neck carcinomas, followed by qPCR validation of key mechanisms. A three-dimensional reconstruction model and tissue atlas of the tree shrew nasopharynx were developed. LC-MS/MS analysis revealed peak DNP accumulation in the nasopharynx at 24 h post-injection (with significantly higher retention compared to other tissues), followed by complete systemic clearance within 72 h. After 12-month chronic DNP intervention, microPET/CT imaging and pathological examination confirmed precancerous lesions or malignant transformation in nasopharyngeal tissues of all tree shrews. Network toxicology highlighted cytochrome P450 (CYP450) enzyme activation as closely associated with malignant progression, with CYP19A1 (HR = 1.52) and CYP2D6 (HR = 0.745) expression showing significant prognostic relevance. qPCR validation demonstrated marked CYP19A1 upregulation and CYP2D6 downregulation in animal nasopharyngeal tissues, indicating their role as key pathogenic biomarkers. These findings confirm DNP’s selective nasopharyngeal accumulation drives carcinogenesis via CYP450 activation, with CYP19A1 overexpression and CYP2D6 suppression may serve as key pathogenic biomarkers and potential regulatory factors in DNP-induced malignant nasopharyngeal transformation.