Dibutyl phthalate (DBP) induces cervical injury and promotes malignant transformation of cervical epithelial cells.

Dibutyl phthalate (DBP), a widespread phthalate with reproductive toxicity and potential carcinogenicity, its cervical effects remain unclear. This study explored DBP's cervical toxicity and mechanisms via epidemiological analysis, network toxicology, and in vivo/in vitro models. Urinary 6 phthalate metabolites in 104 cervical cancer (CC) patients and 104 controls (detected by UPLC-MS/MS) showed elevated levels of MBP, MEHP, MEOHP, MEHHP, MECPP, and ΣDEHP in CC patients; MBP had the strongest CC risk association (adjusted OR = 2.54, P < 0.001). Network toxicology identified 9 core targets of DBP (e.g., CASP3, MAPK8/14, ESR1) and key pathways involved (TNF, MAPK, apoptosis, oxidative stress, etc.). Short-term DBP exposure (mice: 10-50 mg/kg/day; HcerEpic cells: 100-400 μM) induced cervical injury/oxidative stress, suppressed NRF2, and activated MAPK/NF-κB; N-acetylcysteine (NAC) supplementation mitigated damages. Long-term exposure to environmentally relevant DBP concentrations (10-7 M) promoted HcerEpic cell malignant transformation (e.g., enhanced proliferation, migration, invasion, epithelial-mesenchymal transition) via activation of the TGF-β/Smad2/3 and MAPK pathways, with in vivo tumorigenicity validated in nude mice. In conclusion, our findings not only elucidate the molecular mechanisms underlying DBP-induced cervical injury and malignant transformation, but also provide theoretical evidence for evaluating the health risks of phthalates (PAEs) and guiding prevention strategies for environmental pollutant-related female reproductive malignancies.