Identification And Analysis Of Differentially Expressed Proteins Between Papillary Thyroid Carcinoma With Different Iodine Intake And Normal Thyroid Tissue

Objective: In order to find out potential new biomarkers of papillary thyroid carcinoma(PTC),the differentially expressed proteins were investigated between papillary thyroid carcinoma and normal thyroid tissue.At the same time , the differentially expressed proteins were also analysised in PTC between differernt iodine intake status to filter out the closely related proteins with iodine in PTC,so that the role and mechanisms of iodine in the process of PTC formation were explored.Methods:The total proteins of papillary thyroid carcinoma and normal thyroid tissue were separated by two-dimensional gel electrophorsis (2-DE),PTC was divided into high iodine intake group and normal iodine intake group by the urine iodine concentration of patients,normal thyroid tissue near thyroid nodules as control. The 2-DE maps were established for papillary thyroid carcinoma with high iodine intake, papillary thyroid carcinoma with normal iodine intake and normal thyroid tissue respectively.The different expression protein spots were analyzed with Image analysis software, then the peptide mass finger- printing of different expressed proteins were verified by mass spectrum. The functions of the different expressed proteins were identified through UinPort database searching.Results: Fifty-three different protein spots were found between papillary thyroid carcinoma with high iodine intake and normal thyroid tissue by image analysis soft and Nineteen were identified with MALDI-TOF/TOF-MS. Twelve proteins were overexpressed in papillary thyroid carcinoma with high iodine intake,and seven proteins were underexpressed. The overexpressed proteins included CLIC1,Swiprosin-1,PPase,Isocitrate dehydrogenase [NAD] subunit alpha,cytokeratin 18,RNH1 protein,GSH-PX,peroxiredoxin 3,annexin A1,cytoskeletal 19,Galectin-3,glutathione peroxidase,adenosine kinase.The underexpressed proteins were consisted of SAP, tropomyosin-1,vimentin variant 3,cytokeratin 8,tropomyosin-2,α2-Collagentype VI, tubulointerstitial nephritis antigen-like isoform 2 precursor. Fifty-five different protein spots were found between papillary thyroid carcinoma with nomal iodine intake and normal thyroid tissue by image analysis soft and Eleven were identified with MALDI-TOF/TOF-MS. Six proteins were overexpressed in papillary thyroid carcinoma with high iodine intake,and six proteins were underexpressed. The overexpressed proteins included cytoskeletal 19, CD147, annexin A1,carbonyl reductase 1, Mitochondrial Delta3-Delta2- Enoyl-Coa Isomerase,Cathepsin B,carbonyl reductase 1,.The underexpressed proteins were consisted of tropomyosin-1,tropomyosin-2,tubulointerstitial nephritis antigen-like isoform 2 precursor ,fibrinogen beta chain,vimentin variant 3. This was no differentially expressed protein spot between the 2-DE maps of papillary thyroid carcinoma with high iodine intake and the 2-DE maps papillary thyroid carcinoma with normal intake. Bioinformatics data of these differentially expressed proteins were obtained by querying UniProt protein database ,and these proteins may be involved in the composition of tumor cells, cell metabolism, cell cycle regulation and tumor invasion and metastasis.Conclusion: Many different expressed proteins between papillary thyroi d carcinoma and normal thyroid tissue. these differential proteins is closely related to PTC occurs, transformation, progression and metastasis, apoptosis by participating in cell metabolism, cell cycle control, tumor invasion and metastasis.Therefore, the study of these proteins, can exporle the pathogenesis of PTC, screen specific tumor markers, and found that the molecular target for cancer therapy to be used for clinical diagnosis, drug development. This was no significant difference between the 2-DE maps of papillary thyroid carcinoma with high iodine intake and the 2-DE mapsapillary thyroid carcinoma with normal intake. High iodine intake may play a double role .On the one hand ,High iodine intake promotes progress in PTC, on the other hand iodine excess plays a protective role.