The Association of Thyroid Nodule with Non-Iodized Salt among Chinese Children

<div><p>Objective</p><p>The controversy that iodized salt may increase the risk of thyroid disorders has been aroused in China during the past decade. Most of studies focused on adult rather than children. We aimed to explore whether iodized salt was associated with an increased risk of thyroid nodule in Chinese children.</p><p>Methods</p><p>The cross-sectional study was conducted in Hangzhou, China, in 2010. Iodized salt intake, urine iodine concentration (UIC) and thyroid nodule (by ultrasonography) were measured in 3026 children. The associations of iodized salt with thyroid nodule were evaluated using multiple logistic regression models.</p><p>Results</p><p>The prevalence of thyroid nodule was 10.59% among Chinese children. Girls (11.89%) had higher prevalence of thyroid nodule than boys (9.26%). No significant association was observed between type of salt and thyroid nodule in pooled samples, boys and girls, respectively. Similar associations were observed between UIC and thyroid nodule. There was no significant association between milk consumption and thyroid nodule as well.</p><p>Conclusion</p><p>The present study indicated that non-iodized salt may not increase the risk of thyroid nodules among Chinese children. Similar associations were observed between milk consumption, UIC and thyroid nodules.</p></div

POSTN promotes a mesenchymal phenotype in MCF-10A and MCF-7 cells.

<p><b>A.</b> POSTN-overexpressing cells exhibit a mesenchymal-like morphology. <b>B.</b> POSTN promotes cell invasion of human mammary epithelial cells and BCCs as detected by a matrigel-coated transwell invasion assay. <b>C, D.</b> Immunofluorescence analysis revealed that the mesenchymal markers N-cadherin, fibronectin, vimentin and α-SMA in POSTN-expressing cells were increased while the epithelial marker E-cadherin was decreased. <b>E, F.</b> POSTN-expressing cells show increased levels of N-cadherin, fibrnectin, vimentin and α-SMA and decreased E-cadherin. Expression of epithelial and mesenchymal markers was analysed by western blotting.</p

Adjusted associations¹ between types of salt, salt appetite, milk consuming and thyroid nodule among girls of different age group, respectively.

1:<p>Adjustment for age, dietary patterns, resident location, meanwhile, the models of types of salt, milk consumption, salt appetite were adjusted each other.</p>2:<p>Iodized salt indicates that subjects consistently consumed iodized salt; Non-iodized salt indicates that subjects intermittently consumed iodized salt or consistently consumed non-iodized salt.</p

POSTN induces adipogenic and chondrogenic differentiation.

<p><b>A.</b> Following adipogenic differentiation, MCF-10A/POSTN, MCF-7/POSTN cells and hMSCs stained positive with oil red O (top) and fluorescent LipidTox, which stains oil droplets (bottom). <b>B, C.</b> Real-time RT-PCR analysis for the expression of the adipocyte markers <i>PPARγ</i>and <i>ADFP</i> in MCF-10A and MCF-7 cells and their POSTN-overexpressing cells subjected to adipocyte differentiation for 21 days. The data are means ± SD. *P<0.05, **P<0.01. <b>D.</b> Chondrocytic nodules formed by MCF-10A/POSTN cells and hMSCs stained positive with alcian blue 8 GX (left panel). Immunohistochemistry was performed on chondrocyte sections using antibody against collagen II (right panel). MCF-10A/Vector cells, MCF-7/Vector and MCF-7/POSTN cells did not form any chondrocytic nodules under identical conditions.</p

Model of role of POSTN in mammary epithelial neoplasia and metastasis.

<p>POSTN might confer mammary epithelial cells and BCCs with stem cell-like traits and a mesenchymal phenotype, as well as the multipotent potentials of MSCs to promote tumorigenesis and metastasis.</p

The distributions of socio-demographic characteristics among patients with thyroid nodule and no-nodule group among children.

1:<p>Vegetarian indicates that subjects consistently had vegetable diet; meat indicates that subjects consistently had meat diet; moderate indicates that subjects intermittently had vegetable diet or meat diet.</p>2:<p>Iodized salt indicates that subjects consistently consumed iodized salt; Non-iodized salt indicates that subjects intermittently consumed iodized salt or consistently consumed non-iodized salt.</p

Adjusted associations¹ between types of salt, salt appetite, milk consuming and thyroid nodule among boys of different age group, respectively.

1:<p>Adjustment for age, dietary patterns, resident location, meanwhile, the models of types of salt, milk consumption, salt appetite were adjusted each other.</p>2:<p>Iodized salt indicates that subjects consistently consumed iodized salt; Non-iodized salt indicates that subjects intermittently consumed iodized salt or consistently consumed non-iodized salt.</p

POSTN induces osteoblastic and myogenic differentiation.

<p><b>A, B.</b> Following culture in osteoblastic differentiation media for 21 days, MCF-10A/POSTN, MCF-7/POSTN cells and hMSCs were positive for alizarin red S and von Kossa staining. <b>C, D.</b> Relative levels of mRNAs encoding BSP and Runx2 in MCF-10A and MCF-7 cells expressing the vector or POSTN were determined by real-time RT-PCR. <i>Cyclophilin G</i> mRNA was used to normalize the variability in template loading. The data are the means ± SD. *P<0.05, **P<0.01. <b>E.</b> Following myogenic differentiation for 4 weeks, MCF-10A/POSTN cells stained positive for CD56. MCF-7/POSTN cells died under the same myogenic differentiation condition and did not differentiate into myogenic lineages (data not shown). <b>F.</b> Real-time RT-PCR analysis of <i>MyoG</i> and <i>Pax3</i> showing the expression of myogenic markers. The data are the means ± SD. *P<0.05.</p

POSTN-overexpressing cells accelerates the tumor growth and metastatic properties of BCCs.

<p><b>A.</b> 2.5×10⁶ MCF-7/Vector or MCF-7/POSTN cells were injected subcutaneously into 5- to 6-week-old female Balb/c nude mice (n = 4 mice per group). Mice were sacrificed 30 days after injection and examined for the growth of subcutaneous tumors. **P<0.01. <b>B.</b> Tumor weight measurements of 1×10⁶ MDA-MB-231 cells subcutaneously injected into nude mice with 3×10⁶ MCF-10A/Vector cells or MCF-10A/POSTN cells. <b>C.</b> The tumors were measured once or twice per week. Circles, MDA-MB-231 cells; squares, MDA-MB-231 cells plus MCF-10A/Vector cells; triangles, MDA-MB-231 cells plus MCF-10A/POSTN cells; diamonds, MCF-10A/POSTN cells (n = 4 mice per group). **P<0.01. <b>D.</b> Mice subcutaneously implanted with 3×10⁶ MDA-MB-231 mixed with 9×10⁶ MCF-10A/Vector cells or with MCF-10A/POSTN cells (n = 3 mice per group). Twelve weeks after cell injection, the mice were euthanized and the lung metastasis indices for each tumor bearing mouse were determined. *P<0.05. <b>E.</b> Representative haematoxylin-and-eosin-stained sections of lungs of mice bearing the indicated tumors in (D). Scale bar = 500 µm.</p