[Summary] Thyroid cancer is the complicated result of both environmental and genetic factors. Recently with the emergence of genome-wide association study ( GWAS) , the researches on genetic predisposition of thyroid cancer have entered a new phase and revealed a lot of new susceptibility genes or regions. Up to now, there are 11 regions with 16 single nucleotidepolymorphisms in total have been found with GWAS, which provide new ideas for the cause of thyroid cancer and its prevention.

[Summary] Adrenocortical carcinoma is a rare disease with poor prognosis, and its pathogenesis is mainly related to genetic mutations, abnormal expressions of steroidogenic factor-1, insulin-like growth factor 2,cell growth factors including vascular endothelial growth factor, dysfunction of Wnt pathway, as well as dysregulation of microRNA and DNA methylation. In recent years, the intensive molecular studies provide a brand-new methodology to distinguish adrenocortical carcinomas from benign tumors in early stage.

[Summary] Graves'ophthalmopathy ( GO) is the most common extrathyroidal manifestation of Graves disease ( GD) . It is an organ-specific autoimmune disorder. The estimated incidence of GO in the general population is 16 women and 3 men per 100,000 population every year. Approximately 3%-5% of patients with GO are exposed to the potential of losing their sight and requiring optimized medical intervention. For the clinicians it is helpful to assess the degree of activity and severity of GO;both are important in deciding whether a patient requires intervention and which type of intervention is indicated. These interventions include management of hyperthyroidism, measures to relieve local symptoms, immunosuppressive therapies for active moderate and severe GO, and finally rehabilitative surgery for inactive patients.

[Summary] The activities of 17α-hydroxylase and 17,20 lyase of cytochrome P450c17 were evaluated by ELISA in NCI-H295R cells after treatment with palmitate and oleate. The results showed that 0. 75 mmol/L plamitate did not influence the activity of 17α-hydroxylase, but increased the activity of 17, 20 lyase by 74. 3% ( P<0. 05). Oleate at the same concentration did not change the activity of 17,20 lyase. There were no significant changes in the protein expressions of P450c17, P450 oxidoreductase, and cytochrome b5 after treatment with palmitate and oleate. However,reactive oxygen species in cells were elevated by palmitate. The results suggest that exposure to palmitate may increase androgen production by inducing 17, 20 lyase activity of P450c17 in NCI-H295R cells, which is related with oxidative stress-mediated post-translational regulation of the enzyme.

Objective To observe and compare the different orthotopic models of papillary thyroid cancer ( PTC) cell lines of RET/PTC1 rearrangement and BRAFV600E mutation in nude mice. Methods Human PTC cell lines TPC-1, BHP5-16 and BHP2-7 were used. The genotypes of RET/PTC1 rearrangement and BRAFV600E mutation were determined by realtime-PCR and DNA sequencing analysis. The cells(2×105) were injected into the thyroid gland of nude mice. The nude mice were executed at 4th, 12th week, and then their thyroid tumors were removed and weighed. The levels of thyroid hormone were detected using chemiluminescent immunoassay. Results Both TPC-1 and BHP2-7 cells were identified as RET/PTC1 rearrangement by real time-PCR, and the expression of RET/PTC1 rearrangement in BHP2-7 cell was higher than that of TPC-1 cell. BRAFV600E mutation was found in BHP5-16 cell by DNA sequencing analysis, but was not found in TPC-1 and BHP2-7 cells. There were different characteristics in three orthotopic nude model groups. Tumorigenic rates of TPC-1 and BHP5-16 groups were 100%, but the growth of tumor was more rapid in BHP5-16 group than that in TPC-1 group, with more weight tumor. The changes of thyroid hormone levels in BHP5-16 group and TPC-1 group were the same, which were normal at 4th week and sharply decreased at 12 th week(P<0. 05). However, the tumorigenic rate of BHP2-7 group was only 6. 25%. Compared with normal control group, there was no statistical difference in the levels of thyroid hormone in BHP2-7group(P>0. 05). Conclusions It showed difference in the orthotopic models of PTC cell lines of RET/PTC1 rearrangement and BRAFV600E mutation in nude mice. BRAFV600E mutation has obvious impacts on increasing tumorigenic rate and promotion of tumor growth in the orthotopic model. It should not be ignored that advanced thyroid tumor will lead to the destruction of thyroid function.

Objective To investigate the effect and mechanism of liver X receptor ( LXR ) agonist on expression of fatty acid synthase( FAS) in diabetic kidney. Methods In the part of in vivo study, immunostaining was used to detect the FAS protein expression in kidney. 16-week-old male db/db mice on C57BL/6 background were administered via gavage a LXR synthetic agonist, TO901317, at a dose of 3 mg · kg-1 · d-1 or vehicle ( 0. 5%Carboxymethyl Cellulose Sodium, CMC-Na) alone for 7 d;Quantitative RT-PCR and Western blot were used to detect mRNA and protein levels of FAS and SREBP-1. In the part of in vitro study, MCT cell(a mouse murine proximal tubule cell line)was treated with 10μmol/L TO901317 for 24 h or transfected with active SREBP-1c expression vector (SREBP-1cN). HEK293 cells(a human renal tubule cell line)were transfected with mFAS-(1. 7 kb)-luc, LXR expression vector or SREBP-1cN for 12 h. Quantitative RT-PCR and luciferase reproter assay were utilized to examine FAS mRNA level and FAS promoter activity. Results FAS was abundantly expressed in renal cortex, with low expresson in renal glomeruli. The mRNA and protein expressious of FAS in kidney of db/db mice were lowered compared with db/m mice. TO90137 treatment increased FAS mRNA expression by 1. 3-fold. TO901317 increased expression of SREBP-1 in kidneys of db/m and db/db mice by 5. 1-fold and 17-fold, respectively. TO901317 and overexpression of SREBP-1c increased expression of FAS in MCT cells by 1. 5-fold and 1. 8-fold. Transcription activity of FAS were induced by TO901317, LXR, and SREBP-1cN overexpressions in HEK293 cells. Conclusions Both direct(LXRE)and indirect(SREBP-1c)mechanisms may contribute to the up-regulation of FAS expression by LXR in renal proximal tubule cells.

Objective To explore promoter methylation of HIC1 gene and the expression of HIC1/SIRT1 related to the occurrence, development, and metastasis of papillary thyroid carcinoma. Methods Using Bisulfite sequencing PCR to analyze the promoter methylation of HIC1 gene. Using quantitative real-time PCR and Western blot to analyze expression differences of HIC1 and SIRT1 genes in tissues of papillary thyroid carcinoma(40 cases) and in adjacent normal thyroid(40 cases), of which datas were analyzed by statistics. Results The degree of HIC1 gene promoter methylation was significantly higher than that in adjacent normal tissues(P<0. 01). The degree of HIC1 gene promoter methylation in papillary thyroid carcinoma was related to lymph node metastasis, age, and the tumor-node-metastasis stages(P<0. 01). Compared with the expression of HIC1 mRNA and protein in adjacent normal thyroid tissue, that in papillary thyroid carcinoma was significantly lower(P<0. 01), while the expression of SIRT1 mRNA and protein in papillary thyroid carcinoma was significantly higher(P<0. 01). The lower expression of HIC1 mRNA and protein in the tumor tissues was related to the stage of lymph node metastasis, age, and the tumor-node-metastasis stages(P<0. 05). There was a strong negative correlation between the degree of HIC1 gene promoter methylation and expression of HIC1 in papillary thyroid carcinoma(P<0. 05). The expression of HIC1 mRNA and protein between that of SIRT1 also showed a strong negative correlation(P<0. 01). Conclusion Promoter hypermethylation of HIC1 and aberrant expression of HIC1/SIRT1 in papillary thyroid carcinoma may play a significant role in the oncogenesis and progress of papillary thyroid carcinoma. HIC1 is expected to become a new marker for prevention and treatment of papillary thyroid carcinoma.

Objective To compare the diagnostic efficiency of the thyroid imaging reporting and data system (TIRADS), the Bethesda system for reporting thyroid cytopathology(BSRTC) and BRAFV600E detection, and their combined use in the differentiation between benign and malignant thyroid nodules. Methods One hundred and twenty eight patients with 128 thyroid nodules who were scheduled for ultrasound-guided fine-needle aspiration biopsy (FNAB) were recruited for the study. All of them underwent ultrasound, fine-needle aspiration cytology(FNAC) examination, and BRAFV600E detection. TIRADS and BSRTC systems were adopted to judge the ultrasound and FNAC results. The receiver operating characteristic curve was established to assess the diagnostic value of each method. Results The sensitivity, specificity, and AUC of TIRADS were 74. 3%, 84. 5%, and 0. 794, respectively. BSRTC had higher specificity(98. 3%) and equal sensitivity compared to TIRADS. The sensitivity, specificity, and AUC of BRAFV600E detection were the highest ones among the three methods. Combinations of different methods could increase the diagnostic sensitivity and accuracy. The combination of FNAC and BRAFV600E detection significantly increased the diagnostic efficiency(AUC=0. 984), with sensitivity 98. 6% and specificity 98. 3%. Conclusions The diagnostic value of BRAFV600E detection in the differentiation of benign and malignant thyroid nodules is better than both TIRADS and BSRTC, and the combination of FNAC and BRAFV600E detection reaches the best diagnostic efficiency.

[Summary] Lifestyle intervention is one of the important strategies for the prevention of type 2 diabetes. Recently, caloric restriction regimen has become a hot topic as one of the cornerstone of lifestyle intervention. The alternate day fasting regimen is simple, and increases the patient compliance. Both daily calorie restriction and alternate day fasting regimen can reduce body-weight significantly in pre-diabetes subjects, and reduce the visceral fat mass and the fasting insulin levels, and improve the insulin sensitivity, as well as maintain the lean mass, though the effect on fasting blood glucose was not significant. Nevertheless, the most recent studies have demonstrated that daily calorie restriction,in particular, alternate day fasting regimens can be effective in individuals with pre-diebates in order to prevent type 2 diabetes.

[Summary] Hyperuricemia is a syndrome caused by increased production or reduced excretion of uric acid which is characterized by oliguria, anuria, and uremia. Recent studies found that hyperuricemia was correlated with the risk, recurrence, metastasis, and prognosis of cancer. The mechanism may be uric acid associated chronic inflammation and decrease of xanthine oxidoreductase expression in cancer cells. Current treatment of hyperuricemia is to reduce the production of uric acid by inhibition of xanthine oxidoreductase, but the side effects of systemic inhibition of xanthine oxidoreductase received more and more attention. These unwanted side effects underscore the urgent need for mechanism based preclinical studies that can identify optimal strategies for management of hyperuricemia in relevant cancer models.