Thyroid Transcription Factor-1 mRNA Research Articles

The associations of urinary DEHP metabolite levels, serum thyroid hormones, and thyroid-related genes among the adolescent students from China: a cross-sectional study.

Our study aimed to investigate the associations between DEHP exposure and serum thyroid hormone levels in 347 adolescents and young adults. We measured DEHP metabolites including mono(2-ethylhexyl) phthalate (MEHP), mono(2-ethyl-5-oxohexyl) phthalate (MEOHP), mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono(2-ethyl-5-carboxypentyl) phthalate (MECPP), and mono(2-carboxymethyl)hexyl phthalate (MCMHP) in their urine. Total thyroxine (TT4), total triiodothyronine, free triiodothyronine, free thyroxine (FT4), thyroid-stimulating hormone and the mRNA levels of thyroid peroxidase (TPO), thyroglobulin (TG), sodium iodide symporter (NIS), thyroid transcription factor 1 (TTF-1), and paired box gene 8 (PAX-8) in serum were measured. The results of statistical analysis showed that urinary DEHP metabolites were generally negatively associated with TT4 levels in serum. In the males, the FT4 levels showed positive associations with urinary MEHP, MECPP, MCMHP, and ∑DEHP. The mRNA level of TG was significantly positively correlated with the levels of MECPP, MCMHP, and ∑DEHP, while the levels of TTF-1 and PAX-8 mRNA were significantly positively correlated with the levels of DEHP metabolites. Taken together, DEHP may affect the synthesis of TG by altering the normal transcription of TTF-1 and PAX-8, leading to decreased TT4 levels in Chinese adolescents.

Aberrant expression of thyroid transcription factor–1 in schwannomas

Aberrant expression of thyroid transcription factor-1 (TTF-1) has been observed in tumors arising in locations other than thyroid gland, lung and ventral forebrain. However, TTF-1 expression in schwannomas has not yet been studied. Meanwhile, a few inconsistent changes in protein expression have been identified between schwannomas and other peripheral nerve sheath tumors. We evaluated TTF-1 expression in 161 schwannomas and 43 other peripheral nervous system lesions, including ganglioneuromas (n = 8), malignant peripheral nerve sheath tumors (MPNSTs) (n = 11), neurofibromas (n = 24), and traumatic neuromas (n = 9), using immunohistochemistry and verified it using quantitative real-time reverse-transcription polymerase chain reaction (qPCR) to explore TTF-1 expression in peripheral nervous system lesions. Formalin-fixed paraffin-embedded (FFPE) tissues were obtained for both analyses. In this study, we observed nuclear TTF-1 staining in 109 (67.7%) schwannomas, including 102 of 131 (77.9%) conventional, 1 of 20 (5.0%) cellular and 6 of 10 (60.0%) plexiform schwannomas. Nuclear staining was not observed in normal peripheral nerves and non-schwannoma lesions. qPCR verified the aberrant expression and revealed a correlation between TTF-1 protein and mRNA levels (r = 0.633, P = .003). In conclusion, the data from our study show that TTF-1 is selectively expressed in the majority of schwannomas, particularly the conventional variants. Based on this observation, the TTF-1 protein and mRNA are specifically expressed in schwannomas. This highly aberrant expression of varying amounts of TTF-1 may provide new clues to reveal the pathogenesis of schwannoma.

Comparison of immunohistochemistry and mRNA in situ hybridization in detecting thyroid transcription factor-1 expression in non-small cell lung carcinomas tissue

Thyroid transcription factor-1 (TTF-1) reportedly possesses oncogenic and suppressive roles within the same tumor type and may play a dual function in the progression of lung cancer. Immunohistochemistry (IHC) and mRNA in situ hybridization (ISH) are commonly used methods for detecting protein or mRNA expression. The present study compared the concordance rate of the two methods in the evaluation of thyroid transcription factor-1 (TTF-1) expression in non-small cell lung carcinoma (NSCLC) using tissue microarray-based IHC and mRNA ISH. TTF-1 protein and mRNA expression levels were examined in 196 cases of NSCLC. The IHC and mRNA ISH agreement was 91.3% (179/196), and near-perfect agreement was observed between the two methods (κ-coefficient, 0.848). There was no significant difference between IHC and mRNA ISH, as analyzed by the McNemar-Bowker test (P=0.219). The present findings proved that IHC is comparable to mRNA ISH for evaluating TTF-1 expression in NSCLC. These two methods can be used to detect TTF-1 expression in future studies.

Serum microRNA-365 in combination with its target gene TTF-1 as a non-invasive prognostic marker for non-small cell lung cancer.

MicroRNA (miR)-365 functions as a tumor suppressor in non-small cell lung cancer (NSCLC) cells by targeting thyroid transcription factor 1 (TTF-1). To investigate miR-365 and TTF-1 mRNA expression in serum of NSCLC and their associations with patients' prognosis. MiR-365 and TTF-1 mRNA expression in 100 NSCLCs and 100 healthy control sera were detected by quantitative real-time PCR (qRT-PCR). MiR-365 expression level was significantly lower in NSCLC serum samples than in healthy control serum samples (P<0.001), while TTF-1 mRNA expression level was significantly increased in NSCLC serum samples compared to healthy control serum samples (P<0.001). In addition, low miR-365 expression and high TTF-1 expression, alone or in combination, were all significantly associated with poor differentiation (P=0.008, 0.008 and 0.001, respectively), advanced TNM stage (P=0.001, 0.005 and <0.001 respectively) and positive lymph node metastasis (P=0.02, 0.02 and 0.01, respectively) of NSCLC patients. Notably, NSCLC patients with combined low miR-365 expression and high TTF-1 expression (miR-365-low/TTF-1-high) had shortest overall survival (P<0.001). Furthermore, multivariate analysis showed that miR-365 expression (P=0.01), TTF-1 expression (P=0.01), and combined expression of miR-365 and TTF-1 (miR-365/TTF-1, P=0.001) were all independent prognostic factors for overall survival in NSCLC patients. Our data reveal that preoperative serum miR-365 and TTF-1 mRNA levels may be both effective indicators of tumor aggressiveness in human NSCLC. More interestingly, miR-365 and its target gene TTF-1 appear to be synergistic risk factors for the reduction in overall survival of patients with NSCLC.

Expression and clinical significance of the thyroid transcription factor 1 in Xuanwei lung adenocarcinoma

背景与目的通过检测宣威肺腺癌细胞株（XWLC-05）中甲状腺转录因子（thyroid transcription factor 1, TTF-1）mRNA和蛋白表达及宣威肺腺癌标本组织TTF-1和Ki-67蛋白的表达，分析宣威肺腺癌中TTF-1与Ki-67表达相关性及对患者预后的影响。方法利用qRT-PCR方法检测XWLC-05中TTF-1 mRNA和免疫组化分析TTF-1及Ki-67蛋白表达。同时收集2008年1月-2012年3月96例手术后宣威肺腺癌组织标本，免疫组化检测TTF-1及Ki-67的蛋白表达。结果XWLC-05中TTF-1 mRNA低表达，免疫组化TTF-1表达阴性，Ki-67 100%表达。96例肺癌患者TNM分期Ⅰ期-Ⅱ期66%（63/96）、Ⅲ期34%（33/96），TTF-1蛋白表达率93%（89/96），Ki-67为70%（67/96)，其中高分化腺癌TTF-1阳性表达率98%（31/39)，中低分化腺癌89%（51/57)。TTF-1阳性表达随着分化程度的增加而增高（P=0.002），与Ki-67的表达负相关（P=0.01），与性别、年龄、吸烟史及分期无关。Kaplan-Meier生存曲线显示患者中位无进展生存（median progression-free survival, PFS）与分期、TTF-1及Ki-67表达强度有关，Ⅰ期-Ⅱ期PFS高于Ⅲ期（46个月vs 32个月，P=0.001），TTF-1强阳性高于弱阳性和阴性组（45个月vs 35个月，P=0.036），Ki-67弱阳性和阴性高于强阳性组（46个月vs 40个月，P=0.048）。结论TTF-1在肺腺癌中可能是一个肿瘤抑制基因，基于它能抑制Ki-67的表达，并且可作为宣威肺腺癌好的预后指标。

Combination of four gene markers to detect circulating tumor cells in the peripheral blood of patients with advanced lung adenocarcinoma using real-time PCR

The aim of this study was to establish a robust and reliable assay for the detection of circulating tumor cells (CTCs) in the peripheral blood (PB) of patients with advanced lung adenocarcinoma. We used real-time reverse transcription PCR (RT-PCR) to detect survivin, human telomerase reverse transcriptase (hTERT), cytokeratin-7 (CK-7) and thyroid transcription factor 1 (TTF-1) mRNA expression levels in 68 advanced lung adenocarcinoma patients and 30 healthy patients. Statistical analyses were additionally performed to examine the correlation between the mRNA expression levels of these markers with the clinicopathological features of advanced lung adenocarcinoma patients. The sensitivity of these four mRNA markers in the PB of advanced lung adenocarcinoma patients was 41.18, 61.76, 41.18 and 35.29%, respectively. The sensitivity of these four markers combined was 82.35%, which was significantly higher compared with single marker detection. Statistical analysis demonstrated that high expression levels of survivin, hTERT and TTF-1 mRNA are positively correlated with lymph node classification, and high expression levels of survivin, hTERT, CK7 and TTF-1 mRNA are positively correlated with distant metastasis (P<0.05). In addition, overexpression of these four mRNA markers is positively correlated with disease progression (P<0.05). Our data suggest that the combination of survivin, hTERT, CK-7 and TTF-1 mRNA markers may provide a valuable tool for CTC detection and is associated with disease progression in advanced lung adenocarcinoma patients.

Synergistic Effect of Caffeine and Glucocorticoids on Expression of Surfactant Protein B (SP-B) mRNA

Administration of glucocorticoids and caffeine is a common therapeutic intervention in the neonatal period, but possible interactions between these substances are still unclear. The present study investigated the effect of caffeine and different glucocorticoids on expression of surfactant protein (SP)-B, crucial for the physiological function of pulmonary surfactant. We measured expression levels of SP-B, various SP-B transcription factors including erythroblastic leukemia viral oncogene homolog 4 (ErbB4) and thyroid transcription factor-1 (TTF-1), as well as the glucocorticoid receptor (GR) after administering different doses of glucocorticoids, caffeine, cAMP, or the phosphodiesterase-4 inhibitor rolipram in the human airway epithelial cell line NCI-H441. Administration of dexamethasone (1 µM) or caffeine (5 mM) stimulated SP-B mRNA expression with a maximal of 38.8±11.1-fold and 5.2±1.4-fold increase, respectively. Synergistic induction was achieved after co-administration of dexamethasone (1 mM) in combination with caffeine (10 mM) (206±59.7-fold increase, p<0.0001) or cAMP (1 mM) (213±111-fold increase, p = 0.0108). SP-B mRNA was synergistically induced also by administration of caffeine with hydrocortisone (87.9±39.0), prednisolone (154±66.8), and betamethasone (123±6.4). Rolipram also induced SP-B mRNA (64.9±21.0-fold increase). We detected a higher expression of ErbB4 and GR mRNA (7.0- and 1.7-fold increase, respectively), whereas TTF-1, Jun B, c-Jun, SP1, SP3, and HNF-3α mRNA expression was predominantly unchanged. In accordance with mRNA data, mature SP-B was induced significantly by dexamethasone with caffeine (13.8±9.0-fold increase, p = 0.0134). We found a synergistic upregulation of SP-B mRNA expression induced by co-administration of various glucocorticoids and caffeine, achieved by accumulation of intracellular cAMP. This effect was mediated by a caffeine-dependent phosphodiesterase inhibition and by upregulation of both ErbB4 and the GR. These results suggested that caffeine is able to induce the expression of SP-transcription factors and affects the signaling pathways of glucocorticoids, amplifying their effects. Co-administration of caffeine and corticosteroids may therefore be of benefit in surfactant homeostasis.

Thyroid transcription factor 1 represses the expression of Ki-67 and induces apoptosis in non-small cell lung cancer

The thyroid transcription factor 1 (TTF-1) gene is associated with the differentiation of lung epithelial cells and has been reported to be an independent prognostic factor for lung adenocarcinoma patients. The aim of the present study was to detect the expression of TTF-1 in human lung cancer cell lines and to evaluate the association of overexpressed TTF-1 with Ki-67 and apoptosis in the A549 cell line. We also investigated the expression of TTF-1 and Ki-67 in Xuanwei lung adenocarcinoma. TTF-1 mRNA expression was evaluated in 10 non-small cell lung cancer (NSCLC) cell lines by quantitative real-time RT-PCR (qRT-PCR). Overexpression of TTF-1 in A549 cells was achieved by transient transfection. The TTF-1 and Ki-67 proteins were detected by immunohistochemistry and apoptosis was detected by flow cytometry. We also investigated immunohistochemically the expression of TTF-1 and Ki-67 in 62 resected cases of Xuanwei lung adenocarcinoma. Overall the expression of TTF-1 mRNA in the 10 cell lines was low. Overexpression of TTF-1 mRNA was found only in 3 (30%) of 10 NSCLC cell lines, including 1 (25%) of 4 adenocarcinoma cell lines. A549 cells overexpressing TTF-1 were found to have repressed expression of Ki-67 (P=0.012) and increased apoptosis (P=0.000). Immunohistochemical analysis of resected cases of Xuanwei lung adenocarcinoma (n=62) showed the expression of TTF-1 in 58 (93%) of 62 and Ki-67 in 22 (35%) of 62. Patients with strong immunohistochemical expression TTF-1 were statistically associated with well-differentiated phenotype (P=0.006) and inverse correlation with Ki-67 expression (P=0.016). These data suggest that TTF-1 may serve as a tumor suppressor gene based on its inverse correlation with Ki-67 proliferative activity and increase of cellular apoptosis.

Thyroid Transcription Factor-1 Amplification and Expressions in Lung Adenocarcinoma Tissues and Pleural Effusions Predict Patient Survival and Prognosis

Thyroid transcription factor-1 (TTF1) plays a role in lung adenocarcinoma development. We investigated the significance of TTF1 in primary lung adenocarcinomas, lymph node metastases, and malignant pleural effusions (MPEs). We studied TTF1 in 175 primary lung adenocarcinomas, 52 lymph node metastases, and 46 MPE using microarray-based fluorescence in situ hybridization, immunohistochemistry, and messenger RNA (mRNA) in situ hybridization. Real-time reverse transcription polymerase chain reaction was used to investigate correlations between TTF1 amplification and mRNA expression. Correlations between clinicopathologic characteristics, TTF1 amplification, TTF1 expressions, overall survival, and prognosis were analyzed. TTF1 was amplified in 7% of primary lung adenocarcinomas, 4% of lymph node metastases, and 4% of MPE. TTF1 amplification in lung adenocarcinomas was associated with pathologic subtypes (p = 0.029). Patients with positive TTF1 protein and mRNA expressions had improved overall survival if TTF1 was unamplified compared with those with TTF1 amplification (p = 0.068). A multivariate model did not show patients with positive TTF1 expressions tended to have better prognoses if TTF1 was unamplified compared with those with TTF1 amplification (p = 0.068). Survival time was longer for patients with TTF1 expressions in both primary lung tissues (p < 0.001) and MPE (p = 0.045). A multivariate model confirmed the prognostic value of TTF1 expressions in lung adenocarcinoma (p < 0.001). A multivariate model confirmed the prognostic value of TTF1 expressions in lung adenocarcinoma tissues (p < 0.001) while not in MPE (p = 0.058). TTF1 mRNA level was higher in cases with TTF1 amplification compared with those without TTF1 amplification. Patients with lung adenocarcinoma without TTF1 amplification tend to have better prognoses than those with TTF1 amplification in cases with positive TTF1 expressions. Positive TTF1 expressions in lung adenocarcinoma tissues are favorable prognostic parameters in patients with lung adenocarcinoma.

Ontogenic expression profiles of thyroid-specific genes in embryonic and hatching chicks

The last trimester of the embryonic life of chickens is marked by a steady increase in circulating thyroxine (T 4) levels, reaching a maximum around hatching. We have measured thyroidal mRNA expression levels of several genes involved in the biosynthesis of T 4, namely sodium/iodine symporter ( NIS), thyroglobulin ( Tg), thyroid peroxidase ( TPO), thyrotropin receptor ( TSHR), and thyroid transcription factor 1 ( TTF-1), during this period. Subsequently, we measured the expression of these genes in more detail during the entire hatching process and compared the gene expression profiles with concomitant changes in intrathyroidal and circulating thyroid hormone levels. We found that NIS and TPO mRNA expression increased significantly in the perinatal period, whereas Tg mRNA expression rose gradually throughout the last week of embryogenesis but was stable during hatching. TSHR and TTF-1 mRNA levels did not change significantly during the last week of embryonic development and hatching. Our results suggest that the elevated plasma T 4 levels observed in the developmental period studied are caused by an increased synthesis and secretion of T 4 by the thyroid gland. Augmented expression of Tg may play an important role in the increasing T 4 production during the last week of embryonic development, whereas increased NIS and TPO expression around hatching allows the thyrocytes to boost T 4 synthesis even further.

Transcriptional regulation of SP-B gene expression by nitric oxide in H441 lung epithelial cells.

Surfactant protein B (SP-B) is essential for the surface tension-lowering function of pulmonary surfactant. Surfactant dysfunction and reduced SP-B levels are associated with elevated nitric oxide (NO) in inflammatory lung diseases, such as acute respiratory distress syndrome. We previously found that NO donors decreased SP-B expression in H441 and MLE-12 lung epithelial cells by reducing SP-B promoter activity. In this study, we determined the roles of DNA elements and interacting transcription factors necessary for NO inhibition of SP-B promoter activity in H441 cells. We found that the NO donor diethylenetriamine-nitric oxide adduct (DETA-NO) decreased SP-B promoter thyroid transcription factor 1 (TTF-1), hepatocyte nuclear factor 3 (HNF-3), and Sp1 binding activities but increased activator protein 1 (AP-1) binding activity. DETA-NO decreased TTF-1, but not Sp1, levels, suggesting that reduced TTF-1 expression contributes to reduced TTF-1 binding activity. Lack of effect on Sp1 levels suggested that DETA-NO inhibits Sp1 binding activity per se. Overexpression of Sp1, but not TTF-1, blocked DETA-NO inhibition of SP-B promoter activity. DETA-NO inhibited SP-B promoter induction by exogenous TTF-1 without altering TTF-1 levels. DETA-NO decreased TTF-1 mRNA levels and gene transcription rate, indicating that DETA-NO inhibits TTF-1 expression at the transcriptional level. We conclude that NO inhibits SP-B promoter by decreasing TTF-1, Sp1, and HNF-3 binding activities and increasing AP-1 binding activity. NO inhibits TTF-1 levels and activity to decrease SP-B expression. NO inhibition of SP-B expression could be a mechanism by which surfactant dysfunction occurs in inflammatory lung diseases.

Transcription expression and clinical significance of TTF‐1 mRNA in pleural effusion of patients with lung cancer

The aim of this study was to evaluate diagnostic utility of thyroid transcription factor 1 (TTF-1) mRNA in pleural effusions (PEs) of patients with lung cancer, especially primary pulmonary adenocarcinoma (PPA). Transcription levels of TTF-1 were detected by reverse transcription polymerase chain reaction (RT-PCR) in PEs of patients with lung cancer (56 cases) and with lung benign diseases (44 cases). The expression rate of TTF-1 mRNA was significantly higher in PEs of patients with lung cancer (73.2%) than with benign lung diseases (0%). In subclasses, the expression rate of TTF-1 mRNA was obviously higher in PEs of patients with PPA (93.0%) than with metastatic pulmonary adenocarcinoma (0%) and with primary pulmonary squamous cell carcinoma (12.5%). When compared with immunocytochemistry and cytology, TTF-1 mRNA gave the best diagnostic performance in diagnosing PPA: sensitivity of 93.0%, specificity of 100%, and accuracy of 96.6%, respectively. As a molecular marker of detecting pleural micrometastasis, TTF-1 mRNA may be helpful to diagnose the cancer cells in PEs of patients with lung cancer, especially with PPA.

Induction of sodium iodide symporter gene and molecular characterisation of HNF3β/FoxA2, TTF-1 and C/EBPβ in thyroid carcinoma cells

Thyroid carcinoma cells often do not express thyroid-specific genes including sodium iodide symporter (NIS), thyroperoxidase (TPO), thyroglobulin (TG), and thyrotropin-stimulating hormone receptor (TSHR). Treatment of thyroid carcinoma cells (four papillary and two anaplastic cell lines) with histone deacetylase inhibitors (SAHA or VPA) modestly induced the expression of the NIS gene. The promoter regions of the thyroid-specific genes contained binding sites for hepatocyte nuclear factor 3 β (HNF3β)/forkhead box A2 (FoxA2), thyroid transcription factor 1 (TTF-1), and CCAAT/enhancer binding protein β (C/EBPβ). Quantitative reverse transcription-polymerase chain reaction (RT–PCR) showed decreased expression of HNF3β/FoxA2 and TTF-1 mRNA in papillary thyroid carcinoma cell lines, when compared with normal thyroid cells. Forced expression of these genes in papillary thyroid carcinoma cells inhibited their growth. Furthermore, the CpG island in the promoter region of HNF3β/FoxA2 was aberrantly methylated; and treatment with 5-aza-2-deoxycytidine (5-Az) induced its expression. Immunohistochemical staining showed that C/EBPβ was localised in the nucleus in normal thyroid cells but was detected in the cytoplasm in papillary thyroid carcinoma cells. Subcellular fractionation of papillary thyroid carcinoma cell lines also demonstrated high levels of expression of C/EBPβ in the cytoplasm, suggesting that a large proportion of C/EBPβ protein is inappropriately localised in the cytoplasm. In summary, these findings reveal novel abnormalities in thyroid carcinoma cells

Mutational analysis of thyroid transcription factor-1 gene (TTF-1) in lung carcinomas

We studied the expression and mutation of thyroid transcription factor-1 (TTF-1) gene in 92 cases of lung carcinomas comprised of lung adenocarcinoma (36 cases), squamous cell lung carcinoma (42 cases), small cell lung carcinoma (8 cases), and large cell lung carcinoma (6 cases) to investigate whether TTF-1 gene mutation predisposed to the development of lung cancer. Normal lung tissues were obtained from each of the 92 patients. The tissues served as controls. Polymerase chain reaction-single-strand conformation polymorphism, denaturing high-performance liquid chromatography, and DNA sequencing were used to analyze TTF-1 gene mutation and its relationship with the carcinogenesis of lung cancer. We detected the expression of TTF-1 protein and messenger RNA (mRNA) in paraffin-embedded lung carcinomas and their normal lung tissues by tissue microarray. TTF-1 protein and mRNA intensities were measured by Leica-Q500 MC Image Analysis System to reveal their correlation with TTF-1 mutation in lung carcinomas. TTF-1 gene missense and synonymous mutation are present in lung carcinomas with the mutation rate of 16%. TTF-1 protein and mRNA are higher in normal lung tissues than in different lung carcinomas. TTF-1 gene mutation is correlated with the loss of TTF-1 protein and mRNA. The analyses of TTF-1 gene missense mutation and synonymous mutation and the loss of TTF-1 protein and mRNA can be regarded as the important indexes of molecular pathology of lung carcinoma.

Derivation of Lung Epithelium from Human Cord Blood–derived Mesenchymal Stem Cells

Recent studies have suggested that both embryonic stem cells and adult bone marrow stem cells can participate in the regeneration and repair of diseased adult organs, including the lungs. However, the extent of airway epithelial remodeling with adult marrow stem cells is low, and there are no available in vivo data with embryonic stem cells. Human umbilical cord blood contains both hematopoietic and nonhematopoietic stem cells, which have been used clinically as an alternative to bone marrow transplantation for hematologic malignancies and other diseases. We hypothesized that human umbilical cord blood stem cells might be an effective alternative to adult bone marrow and embryonic stem cells for regeneration and repair of injured airway epithelium. Human cord blood was obtained from normal deliveries at the University of Vermont. Cultured plastic adherent cells were characterized as mesenchymal stem cells (MSCs) by flow cytometry and differentiation assays. Cord blood-derived MSCs (CB-MSCs) were cultured in specialized airway growth media or with specific growth factors, including keratinocyte growth factor and retinoic acid. mRNA and protein expression were analyzed with PCR and immunofluorescent staining. CB-MSCs were systematically administered to immunotolerant, nonobese diabetic/severe combined immunodeficiency (NOD-SCID) mice. Lungs were analyzed for presence of human cells. When cultured in specialized airway growth media or with specific growth factors, CB-MSCs differentially expressed Clara cell secretory protein (CCSP), cystic fibrosis transmembrane conductance regulator (CFTR), surfactant protein C, and thyroid transcription factor-1 mRNA, and CCSP and CFTR protein. Furthermore, CB-MSCs were easily transduced with recombinant lentiviral vectors to express human CFTR. After systemic administration to immunotolerant, NOD-SCID, mice, rare cells were found in the airway epithelium that had acquired cytokeratin and human CFTR expression. CB-MSCs appear to be comparable to MSCs obtained from adult bone marrow in ability to express phenotypic markers of airway epithelium and to participate in airway remodeling in vivo.

Quantitative measurement of telomerase reverse transcriptase, thyroglobulin and thyroid transcription factor 1 mRNAs in anaplastic thyroid carcinoma tissues and cell lines

Anaplastic thyroid carcinomas (ATC) are undifferentiated tumors that show rapid progression and dissemination. The recent increase in knowledge about cancer stem cells has attracted marked interest in ATC, since these lesions are suggested to be closely related to thyroid stem cells (TSCs). Due to the rarity of ATCs, however, the gene expression patterns that characterize these lesions have not been fully clarified. Using real-time quantitative reverse transcription-polymerase chain reaction, we measured the mRNA expression levels of three representative genes, telomerase reverse transcriptase (hTERT), thyroglobulin and thyroid transcription factor 1 (TTF-1) in twelve frozen tissue samples of ATC and six cell lines derived from ATCs. All twelve ATC specimens and six ATC cell lines showed an increased expression of hTERT mRNA but the expression levels of hTERT mRNA did not show a clear difference between ATCs and other thyroid tumors. The mean expression level of thyroglobulin mRNA in the ATCs and ATC cell lines was <10(2) times higher than that in the differentiated thyroid carcinomas. All twelve ATCs showed a loss of TTF-1 mRNA expression, but two cell lines, TCO-1 and 8505C, expressed TTF-1 mRNA. In conclusion, ATC tissues and cell lines were characterized by the expression of hTERT and a loss of thyroglobulin expression, concordant with the general recognition. However, the loss of TTF-1 expression can not characterize ATC cells, as some ATC cell lines expressed TTF-1 mRNA abundantly. This information could contribute to clarifying the nature of ATCs and could be useful in detecting TSCs, which have not yet been identified.

TTF-1 regulates growth hormone and prolactin transcription in the anterior pituitary gland

Thyroid transcription factor 1 (TTF-1) is required for morphogenesis of the fetal diencephalon. Previous reports showed that mice carrying a TTF-1 null mutation lacked normal development of the pituitary gland. In this study, a role for TTF-1 in the regulation of growth hormone and prolactin transcription was identified. In-situ hybridization analysis demonstrated TTF-1 mRNA in the growth hormone-producing cells and prolactin-producing cells of the rat anterior pituitary gland. In the GH3 pituitary cell line, we identified TTF-1 as a factor functionally regulating growth hormone and prolactin transcription. TTF-1 activated prolactin transcription, but inhibited growth hormone transcription. Inhibition and activation of growth hormone and prolactin transcription, respectively, by TTF-1 disappeared upon deletion of the TTF-1 binding motifs within the promoters of these genes. These data suggest that TTF-1 plays a regulatory role in the transcription of growth hormone and prolactin genes and may regulate transdifferentiation of cells expressing these two hormones.

Thyroid Transcription Factor-1 Facilitates Cerebrospinal Fluid Formation by Regulating Aquaporin-1 Synthesis in the Brain

In the brain, aquaporin-1 (AQP-1), a water channel for high osmotic water permeability, is mainly expressed in the apical membrane of the ventricular choroid plexus and regulates formation of cerebrospinal fluid (CSF). Although the physiology of AQP-1 has been the subject of several publications, much less is known about the trans-acting factors involved in the control of AQP-1 gene expression. Here we report that TTF-1, a homeodomain-containing transcriptional regulator, is coexpressed with AQP-1 in the rat brain choroid plexus and enhances AQP-1 gene transcription by binding to conserved core TTF-1-binding motifs in the 5'-flanking region of the AQP-1 gene. Intracerebroventricular administration of an antisense TTF-1 oligodeoxynucleotide significantly decreased AQP-1 synthesis and reduced CSF formation. In addition, blockade of TTF-1 synthesis increased survival of the animals following acute water intoxication-induced brain edema. These results suggest that TTF-1 is physiologically involved in the transcriptional control of AQP-1, which is required for CSF formation.

Effects of Nitrofen and Vitamins A, C and E on Maturation of Cultured Human H441 Pneumocytes

Background/Aim: Nitrofen (2,4-dichloro-4´-nitrodiphenyl ether), a teratogen with oxidant properties, induces congenital diaphragmatic hernia (CDH) with lung hypoplasia and delayed lung development and maturation in rat embryos. Several phenotypic features of the alveolar epithelium including surfactant proteins A and B synthesis and its regulation by transcription factors are reproduced in cultured human H441 pneumocytes. The aim of the present study was to test whether vitamins A, E and C with anti-oxidant properties were able to recover the expression of such regulators in an in vitro setting. Materials and Methods: Cultured human H441 pneumocytes were treated with nitrofen with or without additional exposure to vitamins A, E and C. Thyroid transcription factor 1 (TTF-1), hepatocyte nuclear factor 3-β (HNF-3β) and hepatocyte nuclear factor 3-β surfactant protein B (SP-B) mRNAs were measured by real-time polymerase chain reaction (RT-PCR). The cells were also immunohistochemically stained for assessment of proliferation (PCNA) and apoptosis (bis-benzimide) status and SP-B and TTF-1 protein expressions. Results were compared by ANOVA with a significant threshold of 5%. Results: Nitrofen severely decreased TTF-1, HNF-3β and SP-B mRNA expression by H441 pneumocytes in culture. Addition of vitamin E normalized the levels of the three transcripts, while vitamin A normalized only those of TTF-1 and SP-B mRNA. Vitamin C was significantly beneficial only for SP-B transcript. Nitrofen decreased proliferation and TTF-1 and SP-B protein expressions with no apparent effect on apoptosis. Additional exposure to vitamins A, C or E rescued near normal values. Conclusions: The changes induced by nitrofen in cultured H441 human pneumocytes are reverted in part by anti-oxidant vitamins by upregulating TTF-1, HNF-3β and SP-B and stimulating proliferation and maturity in nitrofen-treated cells. These effects of anti-oxidant vitamins could be of some interest for developing new transplacental therapeutic strategies aimed at improving lung development and maturation in fetuses with CDH.

Thyroid Transcription Factor-1 in Orbital Adipose Tissues: Potential Role in Orbital Thyrotropin Receptor Expression

Thyroid transcription factor-1 (TTF-1) is required for maximal expression of thyrotropin receptor (TSHR) in the thyroid. Extrathyroidal TSHR expression is detectable in normal orbital adipose tissues, with increased levels found in orbital tissues from patients with Graves' ophthalmopathy (GO), and in orbital preadipocyte cultures following differentiation. In order to determine whether TTF-1 might be involved in orbital TSHR expression, we used quantitative real-time polymerase chain reaction (PCR) to assess relative expression of this and other thyroid-associated transcription factors (TTF-2 and Pax-8) in GO orbital tissue specimens (n = 28) and cultures (n = 3), and in normal orbital tissues (n = 19) and cultures (n = 3). We detected TTF-1 and TTF-2 mRNA in GO and normal orbital tissue samples, with no difference in levels noted between the tissues. In the GO orbital cultures, TTF-1 mRNA was higher in differentiated than in control (undifferentiated) cultures (p < 0.05), while TTF-2 was unchanged. In the normal cultures, neither TTF-1 nor TTF-2 mRNA levels increased in differentiated cultures. Pax8 was undetectable in all orbital tissues and cell cultures. The presence of mRNA encoding TTF-1 in orbital tissues and cultures suggest that this transcription factor may play an important role in extrathyroidal, as it does in thyroidal, TSHR expression.