Targeted gene therapy has become a promising approach for lung cancer treatment. In our previous work, we reported that the targeted expression of microRNA-7 (miR-7) operated by thyroid transcription factor-1 (TTF-1) promoter inhibited the growth of human lung cancer cells in vitro and in vivo; however, the intervention efficiency needed to be further improved. In this study, we identified the core promoter of TTF-1 (from -1299 bp to -871 bp) by 5' deletion assay and screened out the putative transcription factors nuclear factor-1 (NF-1) and activator protein-1 (AP-1). Further analysis revealed that the expression level of NF-1, but not AP-1, was positively connected with the activation of TTF-1 core promoter in human non-small-cell lung cancer (NSCLC) cells. Moreover, the silencing of NF-1 could reduce the expression level of miR-7 operated by TTF-1 core promoter. Of note, we optimized four distinct sequences to form additional NF-1-binding sites (TGGCA) in the sequence of TTF-1 core promoter (termed as ^optTTF-1 promoter), and verified the binding efficiency of NF-1 on the ^optTTF-1 promoter by electrophoretic mobility shift assay (EMSA). As expected, the ^optTTF-1 promoter could more effectively drive miR-7 expression and inhibit the growth of human NSCLC cells in vitro, accompanied by a reduced transduction of NADH dehydrogenase (ubiquinone) 1α subcomplex 4 (NDUFA4)/protein kinase B (Akt) pathway. Consistently, ^optTTF-1 promoter-driven miR-7 expression could also effectively abrogate the growth and metastasis of tumor cells in a murine xenograft model of human NSCLC. Finally, no significant changes were detected in the biological indicators or the histology of some important tissues and organs, including heart, liver, and spleen. On the whole, our study revealed that the optimized TTF-1 promoter could more effectively operate miR-7 to influence the growth of human NSCLC cells, providing a new basis for the development of microRNA-based targeting gene therapy against clinical lung cancer.
Animals ; Humans ; Mice ; Carcinoma, Non-Small-Cell Lung/therapy* ; Lung Neoplasms/metabolism* ; MicroRNAs/metabolism* ; Nuclear Proteins/metabolism* ; Thyroid Gland/pathology* ; Thyroid Nuclear Factor 1/genetics* ; Transcription Factors/metabolism*

BACKGROUND: Thyroid dysfunction is associated with cardiovascular diseases. However, the role of thyroid function in lipid metabolism remains partly unknown. The present study aimed to investigate the causal association between thyroid function and serum lipid metabolism via a genetic analysis termed Mendelian randomization (MR). METHODS: The MR approach uses a genetic variant as the instrumental variable in epidemiological studies to mimic a randomized controlled trial. A two-sample MR was performed to assess the causal association, using summary statistics from the Atrial Fibrillation Genetics Consortium (n = 537,409) and the Global Lipids Genetics Consortium (n = 188,577). The clinical measures of thyroid function include thyrotropin (TSH), free triiodothyronine (FT3) and free thyroxine (FT4) levels, FT3:FT4 ratio and concentration of thyroid peroxidase antibodies (TPOAb). The serum lipid metabolism traits include total cholesterol (TC) and triglycerides, high-density lipoprotein, and low-density lipoprotein (LDL) levels. The MR estimate and MR inverse variance-weighted method were used to assess the association between thyroid function and serum lipid metabolism. RESULTS: The results demonstrated that increased TSH levels were significantly associated with higher TC (β = 0.052, P = 0.002) and LDL (β = 0.041, P = 0.018) levels. In addition, the FT3:FT4 ratio was significantly associated with TC (β = 0.240, P = 0.033) and LDL (β = 0.025, P = 0.027) levels. However, no significant differences were observed between genetically predicted FT4 and TPOAb and serum lipids. CONCLUSION Taken together, the results of the present study suggest an association between thyroid function and serum lipid metabolism, highlighting the importance of the pituitary-thyroid-cardiac axis in dyslipidemia susceptibility.
Lipid Metabolism/genetics* ; Mendelian Randomization Analysis ; Thyroid Function Tests ; Thyroid Gland ; Thyrotropin ; Thyroxine ; Triiodothyronine

BACKGROUND: The absence of thyroid cysts may indicate latent thyroid damage, as demonstrated in our previous study. However, the association between the absence of thyroid cysts and latent functional damage of the thyroid is unknown. At low thyroid hormone productivity, which may be associated with latent functional damage of the thyroid, the association between thyroid-stimulating hormone (TSH) and hypertension might be enhanced. Therefore, we evaluated the association between TSH level and hypertension stratified by thyroid cyst status. METHODS: We conducted a cross-sectional study of 1724 euthyroid Japanese individuals aged 40-74 years who participated in an annual health checkup in 2014. RESULTS: In the study population, 564 and 686 participants had thyroid cysts and hypertension, respectively. A significant positive association was observed between TSH and hypertension in subjects without a thyroid cyst but not in subjects with thyroid cysts. There was a significant positive association between hypertension and TSH in subjects without a thyroid cyst (odds ratio [OR] 1.27; 95% confidence intervals [CI] 1.01, 1.61) but not in subjects with thyroid cysts (OR 0.79; CI 0.57, 1.09) in the model fully adjusted for known confounding factors. The correlation between the TSH and free triiodothyronine (fee T3) levels (simple correlation coefficient [r] = - 0.13, p < 0.01) was stronger in the subjects without thyroid cysts than in those with thyroid cysts (r = - 0.03, p = 0.525). CONCLUSIONS TSH is positively associated with hypertension only in individuals without thyroid cysts. The correlation between the TSH and free T3 levels was stronger in the subjects without thyroid cysts than in those with thyroid cysts. Therefore, the absence of thyroid cysts could be related to the association between TSH level and hypertension, possibly by indicating that the subjects without thyroid cysts had limited thyroid hormone reserves. Therefore, the absence of thyroid cysts could indicate the latent functional damage of the thyroid.
Aged ; Cross-Sectional Studies ; Cysts/etiology* ; Female ; Humans ; Hypertension/metabolism* ; Japan ; Male ; Middle Aged ; Thyroid Diseases/etiology* ; Thyroid Gland/pathology* ; Thyrotropin/metabolism*

BACKGROUND: A correct thyroid function reference range is important for the accurate diagnosis of thyroid disease during pregnancy. However, there is no consensus on whether thyroid function reference ranges in Chinese population should follow the America Thyroid Association (ATA) guidelines. This study aimed to establish a thyroid function reference range more suited to the Chinese population by evaluating the current thyroid function reference range in pregnant Chinese women and comparing it to the ATA guidelines. METHODS: A total of 52,027 pregnant women were enrolled from January 2013 to December 2016. Thyroid stimulating hormone (TSH), free thyroxine (FT4), and thyroid peroxidase antibody (TPOAb) levels were tested during the first and third trimesters of pregnancy. Reference ranges of TSH and FT4 were established from the 2.5th and 97.5th percentiles of the TPOAb-negative population of women. The Mann-Whitney U test was used to compare thyroid hormones between the TPOAb-positive and TPOAb-negative groups. RESULTS: We obtained that the TSH reference ranges were 0.03 to 3.52 mU/L and 0.39 to 3.67 mU/L, and the FT4 reference ranges were 11.7 to 19.7 pmol/L and 9.1 to 14.4 pmol/L, in the first and third trimester, respectively. If we used the 2011 ATA criteria about 7.0% and 4.0% pregnant women would be over diagnosed in first and third trimester, respectively, compared with local population thyroid hormone reference. When we compared our local criteria with the new 2017 ATA criteria, about 1.2% and 0.8% pregnant women would have a missed diagnosis in first and third trimester, respectively. CONCLUSIONS: Based on our data, which is in line with the current ATA guidelines, a population-based thyroid function reference range would be the first choice for diagnosis of thyroid disease during pregnancy in China. In case such population-based thyroid function reference ranges are unavailable in the east of China, our reference ranges can be adopted, if the same assay is used. TRIAL REGISTRATION www.chictr.org.cn (No. ChiCTR1800014394).
Adult ; Asian Continental Ancestry Group ; Female ; Humans ; Iodide Peroxidase ; metabolism ; Pregnancy ; Thyroid Gland ; metabolism ; physiopathology ; Thyrotropin ; metabolism ; Thyroxine ; metabolism ; Young Adult

Thyroglobulin is the most important and abundant protein in thyroid follicles and has been widely studied as a tumor marker of thyroid cancer recurrence and persistence. Tg is considered the material basis of thyroid hormone synthesis and does not participate in the regulation of thyroid hormone synthesis and secretion. This review summarizes the recent progress in the research of thyroid hormone synthesis and secretion regulation via a negative feedback regulation mechanism by the thyroid-hypothalamus-pituitary axis. Thyroglobulin can negatively regulate the synthesis of thyroid hormone by thyroid follicular cells and antagonize the positive regulation of thyrotropin TSH. The function of thyroid follicular cells is presumably a result of Tg and TSH interaction, and a follicular cycle model is proposed to explain the causes of follicular heterogeneity in glands. We also discuss the prospects and clinical significance of studies into the negative feedback regulation mechanism of the thyroid-hypothalamus-pituitary axis and compare two theories for this mechanism.
Feedback, Physiological ; Humans ; Hypothalamo-Hypophyseal System ; physiology ; Neoplasm Recurrence, Local ; Thyroglobulin ; metabolism ; Thyroid Gland ; physiology ; Thyroid Hormones ; metabolism ; Thyrotropin ; metabolism

Objective: To study the dose-response relationship between maternal thyroid hormone levels in the first twenty weeks of pregnancy and the infant physical and neuropsychological development. Methods: In this prospective cohort study, a total of 945 women and their children were included. Maternal serum samples during first half of the pregnancy were collected and analyzed for levels of thyroid hormones by using the electro-chemiluminescence immunoassay. Maternal social demographic information was collected by using the a self-administered questionnaire. Physical measurements of newborns and neuropsychological evaluation of infants were performed by doctors of maternal and child health care. Results: The differences in newborns' birth length and head circumference were significant among the newborns of mothers with different percentiles of maternal serum (thyroid-stimulating hormone, TSH) levels (P<0.05). Newborns with maternal TSH level ≥P(95) or <P(5) had significantly lower birth length and birth head circumference, compared with the newborns with maternal TSH level between P(25)-P(75) (P<0.05). Newborns' birth head circumferences showed an inverted U-shaped association with maternal serum TSH level (Y=33.940+0.003X-0.109X(2), F=4.685, P=0.009). The difference in mental development index (MDI) of the infants at 18-30 months were significant among the infants of mothers with different percentiles of maternal serum TSH level (P<0.05). Infants with maternal TSH level ≥P(90) showed lower MDI (6.39, 95%CI: 2.29-10.49, P=0.002) compared with the infants with maternal TSH level between P(25)-P(75). Infant's MDI at 18- 30 months also showed an inverted U-shaped association with maternal serum TSH level (Y=103.249-1.524X-0.939X(2), F=6.616, P=0.001). Conclusions: Maternal TSH level was associated with newborn's birth length, birth head circumference and infant's MDI at 18-30 months. Newborn's birth head circumference and infant's MDI at 18-30 months showed an inverted U-shaped association with maternal serum TSH-Z score.
Birth Weight/physiology* ; Child ; Child Development/physiology* ; China ; Female ; Fetal Blood/metabolism* ; Humans ; Infant ; Infant, Newborn/blood* ; Pregnancy ; Prenatal Exposure Delayed Effects/blood* ; Prospective Studies ; Thyroid Gland/physiology* ; Thyroid Hormones/metabolism* ; Thyrotropin/blood*

To investigate the effect of serine/threonine-protein kinase B-Raf (BRAF)-activated long-chain non-coding RNA (lncRNA-BANCR) on apoptosis and autophagy in thyroid carcinoma cells and the underlying mechanisms.
 Methods: RT-PCR was used to detect the expression of lncRNA-BANCR in thyroid carcinoma and normal thyroid tissues. The association between lncRNA-BANCR and clinicopathological data was analyzed in patients with thyroid cancer. Cell counting kit-8 (CCK-8) was used to detect the effect of lncRNA-BANCR on the proliferation of thyroid cancer cells. The effect of lncRNA-BANCR on the apoptosis of thyroid carcinoma cells was detected by flow cytometry. Transwell invasion assay was used to detect the effect of lncRNA-BANCR on the invasive ability of thyroid cancer cells. Western blot was used to detect the changes of autophagy proteins LC3-I and LC3-II after the lncRNA-BANCR expression was suppressed.
 Results: Compared with normal thyroid tissues, the expression level of lncRNA-BANCR in thyroid carcinoma tissues was elevated (P<0.05). The expression of lncRNA-BANCR was positively related to the pathological stage of thyroid carcinoma and the lymph node metastasis. Inhibition of lncRNA-BANCR expression attenuated the proliferation and invasion ability of thyroid cancer cells (both P<0.05); but the apoptosis was enhanced (P<0.05); the expression levels of autophagy protein LC3-I and LC3-II were also increased (P<0.05).
 Conclusion: The expression level of lncRNA-BANCR affects the proliferation, invasion and apoptosis of thyroid cancer cells through modulation of autophagy behavior.
Apoptosis ; Autophagy ; Cell Proliferation ; Gene Expression Regulation, Neoplastic ; Humans ; Neoplasm Invasiveness ; Proto-Oncogene Proteins B-raf ; metabolism ; RNA, Long Noncoding ; metabolism ; Serine ; metabolism ; Threonine ; metabolism ; Thyroid Gland ; cytology ; metabolism ; Thyroid Neoplasms ; metabolism ; pathology

Thyroid hormone plays an important role in bone remodeling. In overt hyperthyroidism, excess thyroid hormone accelerates bone turnover and shortens the normal bone remodeling cycle, leading osteoporosis and increased fracture risk. Several population and case-control studies have demonstrated that a prior history of hyperthyroidism is an independent risk factor for hip and vertebral fracture. In contrast, bone remodeling cycle is prolonged to almost 2 years with an increase in mineralized cortical bone in overt hypothyroidism. Some cross-sectional and longitudinal studies have suggested that thyroid hormone replacement could decrease bone mineral density in overt hypothyroidism. However, this effect might be interpreted as an adaptive mechanism on decreased bone turnover in preexistent hypothyroidism, and not as thyroid hormone induced bone loss. The effect of thyroid hormone replacement for hypothyroidism on fracture risk has not been investigated well. However, excessive thyroid hormone treatment might be increased the risk of fracture.
Bone Density ; Bone Remodeling ; Case-Control Studies ; Hip ; Hyperthyroidism ; Hypothyroidism ; Longitudinal Studies ; Metabolism ; Miners ; Osteoporosis ; Risk Factors ; Thyroid Gland

Thyroid cancer is one of the most common malignancies of endocrine organs, and its incidence rate has increased steadily over the past several decades. Most differentiated thyroid tumors derived from thyroid epithelial cells exhibit slow-growing cancers, and patients with these tumors can achieve a good prognosis with surgical removal and radioiodine treatment. However, a small proportion of patients present with advanced thyroid cancer and are unusually resistant to current drug treatment modalities. Thyroid tumorigenesis is a complex process that is regulated by the activation of oncogenes, inactivation of tumor suppressors, and alterations in programmed cell death. Mitochondria play an essential role during tumor formation, progression, and metastasis of thyroid cancer. Recent studies have successfully observed the mitochondrial etiology of thyroid carcinogenesis. This review focuses on the recent progress in understanding the molecular mechanisms of thyroid cancer relating to altered mitochondrial metabolism.
Carcinogenesis ; Cell Death ; Epithelial Cells ; Humans ; Incidence ; Metabolism* ; Mitochondria ; Neoplasm Metastasis ; Oncogenes* ; Prognosis ; Quality Control* ; Thyroid Gland* ; Thyroid Neoplasms*

OBJECTIVETo evaluate the usefulness of the thyroglobulin (Tg) level in adults as a nutritional biomarker of iodine status and to identify the factors related to the serum Tg level.

METHODSA cross-sectional study was conducted in adult populations of areas differing in iodine nutrition from three provinces (Autonomous Region) in China. Serum levels of thyroid hormones and Tg as well as thyroid autoantibodies were measured. The thyroid volume and nodule were measured by ultrasound. A multivariate linear regression analysis was used to assess iodine intake and other indeterminate factors associated with the serum Tg level.

RESULTSA total of 573 adults were recruited for this study. The serum Tg levels differed significantly among the three groups (22.27 μg/L, 9.73 μg/L and 15.77 μg/L in the excess, more-than-adequate, and deficient groups, respectively). The results of multivariate linear regression analysis indicate that excess and deficient iodine intake, goiter, thyroid nodule, hypothyroidism are significantly related with higher Tg level, and TgAb positivity is significantly related with lower serum Tg.

CONCLUSIONThe serum Tg level reflects abnormal thyroid function and is a sensitive functional biomarker of iodine nutrition status.

Adult ; Biomarkers ; blood ; China ; Cross-Sectional Studies ; Female ; Humans ; Iodine ; Male ; Middle Aged ; Thyroglobulin ; blood ; Thyroid Diseases ; blood ; Thyroid Gland ; metabolism