Proteomics Analysis Of Plasma Derived Extracellular Vesicles During Development Of Tongue Squamous Cell Carcinoma In Rat Model

Chapter 1 4NQO Induced Oral Squamous Cell Carcinoma[Objective] In this study,we applied 4NQO to induce tongue squamous cell carcinoma in Wistar rats to obtain tongue and plasm of health rats,rats with TPL,and rats with TSCC.[Methods]4NQO was prepared into 2% mother liquor with 1,2-propylene glycol and then prepared into 40 g/m L solution with sterilized tap water.Wistar rats aged 5 weeks were randomly divided into experimental group and control group.Rats in the experimental group drank 40 g/ml 4NQO solution,while rats in the control group drank sterilized tap water.After 24 weeks of the intervention,the intact tongues and plasma of the rat were dissected after sacrifice.Histopathological evaluation was performed to evaluate the development of TPL and TSCC.[Results]4NQO successfully induced TPL and TSCC in Wistar rats.After the intervention of 4NQO,white lesions,erosion,ulcer,and neoplasms appeared.Histopathological evaluation showed the classic pathological change from simple epithelial hyperplasia to carcinoma in TSCC.In the control group,no obvious abnormalities in morphology and histopathology were observed on the lingual mucosa.[Conclusions]TPL and TSCC in Wistar rats were successfully induced by 4NQO.Chapter 2 Proteomics of Plasma Derived Extracellular Vesicles during Development of Oral Squamous Cell Carcinoma in Rat Model[Objective]To explore the potential biomarkers in TPL and TSCC,the protein expression profile of EVs from plasma was detected by proteomics analysis.[Methods]The EVs were extracted by exo Easy Maxi kit and identified by Nanoparticle tracking analysis,transmission electron microscopy,and western blot.EVs were then digested with enzyme,marked by TMT,identified,and quantitatively analyzed by mass spectrometry.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were performed.Protein-Protein interaction network of differentially expressed proteins was constructed.[Results] EVs isolated from plasma were successfully identified by Nanoparticle Tracking Analysis,transmission electron microscopy,and western blot.A total of 1660 proteins were identified.Principal component analysis,sample correlation analysis,and sample hierarchical clustering analysis confirmed the differences between the groups.Compared with healthy controls,749 and 593 differentially expressed proteins were identified in TPL and TSCC,respectively.These differentially expressed proteins are co-enriched in pathways such as Cell proliferation,translation,epithelial structure,pseudopod,and adhesion plaques.Protein-Protein interaction network suggests the potential activation of translation and RNA transport in the development of TPL and TSCC.[Conclusions] The protein expression profile of plasma EVs changes with the development of TSCC.This change might reflect some physiological and pathological changes such as proliferation and metabolism.Plasma EVs can provide a direction for the study of biomarkers and mechanisms of TPL and TSCC.