The effect of melittin intervention on murine cervical cancer cells: An in-depth proteomics investigation

Melittin, the principal bioactive peptide of bee venom, exhibits promising antitumor activity, whereas its molecular mechanisms in cervical cancer remain incompletely understood. In this study, the biological effects and molecular responses of melittin in U14 cervical cancer cells were investigated using Astral data-independent acquisition (Astral-DIA)-based quantitative proteomics combined with molecular validation. The effects of melittin on cell migration, invasion, and cell death were evaluated by Transwell assays and PI/Hoechst staining. Differentially expressed proteins (DEPs) were screened and subjected to Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and protein-protein interaction (PPI) analyses. Representative oxidative stress-related genes and proteins were further validated by RT-qPCR and Western blotting. Melittin significantly inhibited the migration and invasion of U14 cervical cancer cells and increased cell death. Quantitative proteomics identified 9,782 protein groups and 187 DEPs, including 71 up- and 116 down-regulated proteins. KEGG pathway enrichment analysis revealed oxidative phosphorylation (OXPHOS) as the most significantly enriched pathway, together with glutathione metabolism, ferroptosis-related pathways, reactive oxygen species signaling, and mitophagy. GO term enrichment analysis indicated that DEGs were mainly engaged in mitochondrial function, electron transport, oxidoreductase activity, and energy metabolism. RT-qPCR assay demonstrated altered expression of Duox1, Gpx4, Gsx2, Nfe2l2, and Gstp2. Additionally, PPI analysis identified Gstp2 and ODC1 as representative hub proteins involved in redox regulation and metabolic adaptation. Furthermore, Western blotting confirmed increased GSTP2 expression following melittin treatment. Overall, these findings provide a comprehensive proteomic landscape of melittin-treated U14 cervical cancer cells and suggest that mitochondrial OXPHOS remodeling and redox-associated pathways may contribute to the antitumor activity of melittin.