1.A Study On The Relationship Between Thyroid Function And Smoking Of Chinese Urban Residents In 10 Cities 2.The Role And Clinical Significance Of DPP4 In The Pathogenesis Of Papillary Thyroid Carcinoma

Part Ⅰ:A Study on the Relationship between Thyroid Function and Smoking of Chinese Urban Residents in 10 Cities.concentrations in different smoking status.Multiple linear regression was used to analyze the influencing factors of serum TSH,TPOAb,TGAb and UIC concentrations.Thyroid gland affects metabolism,growth and development of the body,and thyroid dysfunction has a significant impact on the general population.It is a serious health problem,and has become the second largest disease in the field of Endocrinology.This study aimed to investigate the relationship between smoking and serum thyroid hormone concentration,the relationship between smoking and urinary iodine,and thequantitative relationship between smoking and TSH,TPOAb,TGAb and UIC concentration.Objective1.To describe the serum levels of TSH,TPOAb,TGAb and other thyroid hormones and UIC levels of Chinese urban residents.2.To carry out a quantitative analysis on the relationship between smoking and TSH,TPOAb,TGAb and UIC of urban residents.MethodsTen Chinese cities,Shenyang,Beijing,Jinan,Xi’an,Nanjing,Shanghai,Wuhan,Chengdu,Guiyang and Guangzhou,were selected as the investigation sites.According to the principle of multistage random sampling,samples were taken randomly in ten cities of the country.The respondents were permanent residents aged 20 or older who would not move in recent years.The cross-sectional study was conducted from March 2009 to October 2010 to perform face-to-face interviews and field investigation.The subjects received questionnaires(mainly including demographic characteristics,iodine consumption,smoking status,etc.),physical examination,thyroid ultrasound examination,sample collection,etc.Besides,the levels of thyroid-stimulating hormone(TSH),thyroid peroxidase antibody(TPOAb),thyroglobulin antibody(TGAb)and urinary iodine concentration(UIC)were measured in the laboratory.Kruskal-Wallis rank sum test and approximate t test were adopted to compareserum TSH,TPOAb,TGAb and UICResults1.A total of 7784 people(57.4%)were investigated in the area of iodine sufficient quantity.5768 people(42.6%)were investigated in the area of iodine excess.The number of people surveyed in Guizhou was the largest(11%),and the number of peopleinvestigated in Shenyang was the least(5.5%).2.The average level of serum TSH was 3.25±4.83 mU/L,the average level of serum TPOAb was 39.18±108.51 U/ml,the average level of serum TGAb was 91.89±356.59 U/ml,the average level of serum FT3 was 5.02±2.43 pmol/L,the average level of serum FT4 was 16.62±5.15 pmol/L,and the median of urine iodine was 238.59±150.25 μg/L.3.There was a significant difference(P<0.05)in TSH,TPOAb,TGAb and UIC concentration.The TSH concentration in regular smokers was the lowest(2.73±3.78 mU/L),the level of TPOAb concentration in regular smokers was the lowest(26.71±82.42 U/ml),the TGAb concentration of regular smokers was lowest(47.69±263.73 U/ml).The highest concentration of UIC(249.02±149.16 μg/L)was observed.There was no statistical difference in TSH,TPOAb and TGAb for exposure to second-hand smoke(P>0.05),and the average concentration of UIC in the subjects exposed to secondhand smoke was significantly higher than that of non-exposed ones(P<0.05).4.There was a significant relationship between sex,iodine status,age,family history of thyroid disease,monthly incomeper capita,active smoking and serum TSH level(P<0.05).Smoking could lead to the decrease of serum TSH concentration(β=-0.137).5.Gender,active smoking,family history of thyroid disease,age,iodine,seaweed,and salt source were significantly related with serum TPOAb level(P<0.05).Smoking could lead to the decrease of serum TPOAb concentration(β=-8.018).6.There was a significant relationship between gender,family history of thyroid disease,age,active smoking and the level of serum TGAb(P<0.05).Smoking could lead to the decrease of serum TGAb(β=-53.214).7.There was a significant relationship between age,gender,cultural degree,the condition of seaweed,monthly income per capita,BMI and UIC(P<0.05)in the area ofsufficient iodine.There was a significant relationship between age,seaweed,monthly income,active smoking,salt source,BMI and UIC(P<0.05)in the area of excessive iodine.The level of UIC was increased in areas where iodine excess was sufficient(β=5.145).Conclusion1.Based on the study of Chinese urban residents in 10 cities,serum TSH,TPOAb and TGAb levels were lower in active smokers than in non-smokers,and active smokers’UIC levels were higher than passive smokers.While passive smokers’ UIC levels were higher than non-exposed ones.2.As an important environmental factor,smoking plays an important role in the process of thyroid dysfunction.Part Ⅱ The role and clinical significance of DPP4 in the pathogenesis of papillary thyroid carcinomaObjectiveHashimoto’s thyroiditis(HT)and papillary thyroid carcinoma(PTC)are two common nodular thyroid diseases,and their relationship has been the focus of researchers,CD26,also known as dipeptidyl peptidase 4(DPP4),is an important molecule involved in glucose metabolism.It can regulate the expression level of cytokines through its enzymatic activity,and can also play a physiological role as a protein receptor.It has strong stability and solubility in blood and body fluids,making it a good serum marker.This article investigates the role and clinical significance of DPP4 in the pathogenesis of HT and PTC.By clarifying the expression of DPP4 in HT and PTC patients,it points out that DPP4 is a differential diagnosis marker for HT and PTC,exploresthe mechanism of DPP4 in inducing T cell differentiation and function,and deepens understanding of the pathogenesis of PTC.The understanding of the pathogenesis of PTC provides a theoretical basis for DPP4 as a biomarker or therapeutic target for the differential diagnosis of benign and malignant thyroid nodules.MethodsDownload the thyroid tumor gene chip dataset(GPL8300,Series GSE29315),and use the R language cloning analysis package to analyze the expression profiles of the thyroid tissues of each of the 6 patients with HT and PTC.A total of 191 patients with thyroid nodules weredivided into the HT group,the PTC group,and the benign nodules group.Clinical and pathological data were compared.Serum and tissue samples were detected by qPCR and western blotting at the gene and protein levels,respectively.The serum DPP4 concentration and DPP4 activity were detected by ELISA.The expression of CD26 in tissues was detected by immunohistochemistry.CD3+T cells and CD4+CD25+T cells were sorted by immunocytes sorting technique.The proportion of tissue cell subsets and the expression of GLUT1 on the surface of CD8+T cell membrane was analyzed by flow cytometry.siRNA interference and overexpression technique was used to evaluate the effect of DPP4 enzyme activity on T cell effector function.Data were used as mean±standard deviation.The t test was used to compare the two sets of independent data.The variance analysis,Welch method or H test was used to compare multiple sets of quantitative data;the rank correlation was used for correlation analysis between variables,and the chi-square test or Fisher exact probability method was used to compare the classified data.Results1.High expression of DPP4 in tissues of papillary thyroid cancer patients.(1)Cluster analysis of thyroid nodule gene chip in HT and PTC patients revealed a protein molecule DPP4 highly expressed in PTC.(2)GO enrichment analysis of differential genes in HT and PTC patients,found that compared with HT patients,PTC patients up-regulated cell proliferation regulation,cell migration,cell signal transduction,epithelial cell differentiation,phylogenetic development,and tissue differentiation and other related functional gene expression.There was down-regulation of immune system development,immune function,leukocyte activation regulation,cell surface receptor signaling pathway,protective response,positive regulation of immune system processes and other related gene expression.(3)KEGG enrichment analysis of differential genes in HT and PTC patients showed that the most obvious signaling pathways in PTC patients compared with HT patients were:tumor transcriptional disorder,cell adhesion molecule,tumor signaling pathway and tumor proteoglycan and so on.Down-regulated signaling pathways are concentrated in leukocyte transendothelial migration,T cell receptor signaling pathways,innate immune defense,cytokine signaling pathways,NK cell-mediated cytotoxicity,and NF-κB signaling pathways.2.DPP4 has better PTC diagnostic performance(1)The serum DPP4 concentration in PTC patients was 544.28±284.96 ng/ml,which was significantly higher than 418.57±215.73 ng/ml in patients with HT and 410.64±263.78 ng/ml in patients with thyroid nodules.Statistical significance(P<0.05).(2)The serum DPP4 activity of PTC patients was 11.57±0.49μg/ml,which was significantly higher than that of HT patients 10.35±0.99μg/ml and thyroid nodules patients 10.65±1.18μg/ml,compared with the two groups.Statistical significance(P<0.05).(3)To analyze the correlation between the clinical and pathological data of the patients enrolled,and to compare the TPOAb and TGAs that are most relevant to the diagnosis of HT,the TSH associated with PTC,and the activity of DPP4 and DPP4,and found that the serum TPOAb was positively correlated with the concentration of TGAb(r=0.65,P<0.05),serum DPP4 concentration was positively correlated with DPP4 enzyme activity(r=0.281,P<0.05).(4)Serum DPP4 diagnosis the area under the ROC curve of PTC is 0.632(95%CI:0.530-0.733),and the area under the ROC curve of DPP4 enzyme diagnosis PTC is 0.707 higher than the DPP4 serum concentration.Serum DPP4 concentration>409.78 ng/ml can be used for the diagnosis of PTC(sensitivity=0.625,specificity=0.727),serum DPP4 enzyme activity≥10.84μg/ml can be used for the diagnosis of PTC(sensitivity=0.781,specificity=0.673).Serum DPP4,DPP4 enzyme activity has a good diagnostic value of HT and PTC.3.DPP4 participates in the occurrence of PTC by inducing the production of regulatory T cells(Treg)and inducing effector T cell depletion(1)DPP4 is down-regulated in Nthy-ori-3-1 cells of normal thyroid cells,and DPP4 is highly expressed in thyroid papillary carcinoma cell lines BCPAP and TPC1.Recombinant human thyrotropin can induce normal thyroid follicular epithelial cells Nthy-ori-3-1 expresses DPP4.(2)In nodular tissue of simple thyroid nodules and PTC patients,DPP4 is mainly located in the cytoplasm and membrane of thyroid epithelial cells,especially the luminal surface.The positive rate of DPP4 expression in PTC patients was significantly higher than that in patients with thyroid nodules(95%CI:0.610-0.803),and DPP4 enzyme activity is used as a diagnosis.The PTC value is(P<0.05).The PTC patients had high expression of DPP4 in cancer tissues,and the adjacent tissues in the same section were almost not expressed.(3)Compared with simple nodule tissue,PTC tumor nodule tissue had higher Treg infiltration rate(P<0.05).DPP4 high expression thyroid cell follicular epithelial cell stable strain Nthy-ori-3-1 was established,and was co-incubated with CD4+CD25+T cells.It was found that DPP4 high expression of thyroid cells could induce Treg cells more effectively(P<0.05).Interfering with the expression of DPP4 in the thyroid papillary carcinoma cell line TPC1 in the co-incubation system with CD4+CD25+T cells,it was found that the down-regulation of DPP4 inhibited the production of Treg induced by TPC1 cells(P<0.05).(4)DPP4 inhibitor K579 can enhance the fluorescence intensity of Glucose transporter type 1(GLUT1)in CD8+T cells(P<0.05).Conclusion1.In the PTC patients with high expression of protein molecule DPP4,PTC patients up-regulated the expression of functional genes related to malignant behaviors such as cell proliferation regulation,cell migration and epithelial cell differentiation,down-regulated immune system development,immune effector function and leukocyte activation regulate the expression of genes involved in immune activation.2.The serum DPP4 and DPP4 activities have better diagnostic value of HT and PTC,and provide a theoretical basis for CD26/DPP4 as a biomarker or therapeutic target for differential diagnosis of benign and malignant thyroid nodules.3.DPP4 may mediate the occurrence of PTC by inducing Treg production and inducing effector T cell depletion.