BACKGROUNDT cell factor-4 (TCF-4) plays an important role in development and carcinogenesis. Recently, the role of TCF-4 has been described in colon cancer and other cancers. However, whether TCF-4 plays a similar role in lung cancer is unknown. To answer this question, we studied the expression of TCF-4 protein and mRNA in non-small-cell lung cancer (NSCLC) and the relation of TCF-4 expression pattern to histological type and cell differentiation.

METHODSTissue samples from sixty cases of pathologically diagnosed NSCLC and eight normal tissue samples were obtained between September 2001 and March 2003. Immunohistochemistry was used to investigate the distribution of TCF-4 protein. The staining patterns of the tumors were divided into 4 categories: nuclear staining alone or nuclear staining greater than cytoplasmic staining; cytoplasmic staining or cytoplasmic staining greater than nuclear staining; equal nuclear and cytoplasmic staining; no nuclear staining or cytoplasmic staining. The integrated optical density (OD) values of all sections were analyzed by UIC MetaMorph image analysis software. The expression of TCF-4 mRNA was detected by one-step reverse transcription-polymerase chain reaction (RT-PCR). The integrated density values of the PCR products were analyzed semi-quantitatively.

RESULTSImmunohistochemistry showed that there was no expression of TCF-4 in normal tissue. However, TCF-4 was expressed in 86.7% (52/60) of NSCLC samples, mainly in the nuclei of tumor cells. Furthermore, there was a significant difference in TCF-4 localization patterns between squamous cell carcinomas and adenocarcinomas (P < 0.05). The integrated OD values of TCF-4 expression was significantly higher in tumors with moderate-poor cell differentiation than in well differentiated tumors (51.63 +/- 6.67 vs 46.13 +/- 12.31, P < 0.01). There was no TCF-4 mRNA expression in normal tissue. However, 63.9% (23/36) of carcinoma samples expressed TCF-4 mRNA. TCF-4 mRNA expression was significantly higher in tumors with moderate-poor cell differentiation than in well differentiated tumors (P < 0.05). There were no significant differences in mRNA expression in comparison with histological type.

CONCLUSIONSThe sub-cellular distribution of TCF-4 may correlate with NSCLC histological type. High expression of TCF-4 mRNA and protein may be associated with the degree of cell differentiation in NSCLC.

Carcinoma, Non-Small-Cell Lung ; chemistry ; Cytoskeletal Proteins ; metabolism ; Female ; Humans ; Immunohistochemistry ; Lung Neoplasms ; chemistry ; Male ; Middle Aged ; RNA, Messenger ; analysis ; TCF Transcription Factors ; Trans-Activators ; metabolism ; Transcription Factor 7-Like 2 Protein ; Transcription Factors ; analysis ; genetics ; beta Catenin

Carcinoma, Non-Small-Cell Lung ; metabolism ; pathology ; Cell Membrane ; metabolism ; Cell Nucleus ; metabolism ; Cytoplasm ; metabolism ; Humans ; Lung Neoplasms ; metabolism ; pathology ; Signal Transduction ; TCF Transcription Factors ; metabolism ; Transcription Factor 7-Like 2 Protein ; Wnt Proteins ; physiology ; beta Catenin ; metabolism

OBJECTIVEThe goal of this study is to investigate the inappropriate activation of Wnt pathway in the hepatocarcinogenesis.

METHODSWe analyzed the alterations of three key components of Wnt pathway, beta-catenin, glycogen synthase kinase 3beta (GSK-3beta) and T cell factor 4 (Tcf-4), in 34 samples of hepatocellular carcinoma (HCC) and paracancerous normal liver by immunohistochemistry, polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP), direct sequencing, semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and in situ hybridization.

RESULTSWe found 61.8% (21/34) of all the HCCs examined showed an abnormal beta-catenin protein accumulation in the cytoplasm or nuclei. RT-PCR-SSCP and direct sequencing showed that beta-catenin exon 3 mutations existed in 44.1% (15/34) of the HCCs. No mutations of GSK-3beta or Tcf-4 were detected in HCCs. Moreover, mRNA of beta-catenin and Tcf-4 but not GSK-3beta was found to be over expressed in HCCs. On analyzing the relationship between alterations of beta-catenin or Tcf-4 and C-myc or Cyclin D1 expression, we found that the mutations of beta-catenin as well as over expression of beta-catenin or Tcf-4 gene were independently correlated with C-myc gene over expression in HCCs.

CONCLUSIONSOur present findings strongly suggest mutations of beta-catenin as well as over expression of beta-catenin and Tcf-4 gene activate the Wnt pathway in HCC independently with the target gene most likely to be C-myc.

Carcinoma, Hepatocellular ; metabolism ; Cytoskeletal Proteins ; genetics ; physiology ; Glycogen Synthase Kinase 3 ; genetics ; physiology ; Glycogen Synthase Kinase 3 beta ; Humans ; Immunohistochemistry ; Liver Neoplasms ; metabolism ; Polymerase Chain Reaction ; Polymorphism, Single-Stranded Conformational ; Proto-Oncogene Proteins ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; TCF Transcription Factors ; Trans-Activators ; genetics ; physiology ; Transcription Factor 7-Like 2 Protein ; Transcription Factors ; genetics ; physiology ; Wnt Proteins ; Zebrafish Proteins ; beta Catenin

OBJECTIVES: To observe the effect of type 2 diabetes mellitus (T2DM) on mandibular bone regeneration and the expression of factors related to T helper cell 17 (Th17 cell) and regulatory T cell (Treg cell) in mice. METHODS: Thirty-six 6-week-old C57BL/6J male mice were randomly divided into normal control (NC) and T2DM groups. Fasting blood glucose levels were detected 0 d, 7 d, 14 d, and 28 d after surgery for mandibular defects. Hematoxylin-eosin (HE) staining was used in observing the bone after 7 d, 14 d, and 28 d of the healing process. Immunohistochemical staining was used in observing the expression of alkaline phosphatase (ALP), Runt-related transcription factor 2 (RUNX2), forkhead box protein P3 (Foxp3), retinoic acid related orphan receptor gamma T (RORγt), and protein tyrosine phosphatase non-receptor type 2 (PTPN2) after 7 d, 14 d, and 28 d of healing. RESULTS: HE staining showed that the area with new bones in the T2DM group was significantly smaller than that in the NC group. Immunohistochemical staining showed that the expression of osteogenesis related proteins ALP and RUNX2 were significantly reduced in the T2DM group. In addition, the number of RORγt positive cells increased, whereas the number of Foxp3 positive cells and the expression PTPN2 decreased significantly in the mandibular bone defect in mice with T2DM. CONCLUSIONS T2DM significantly inhibit mandibular bone regeneration in mice. Decline in PTPN2 expression and the transition of Treg and Th17 may be the underlying molecular mechanisms.
Animals ; Bone Regeneration ; Diabetes Mellitus, Type 2 ; Forkhead Transcription Factors ; Male ; Mice ; Mice, Inbred C57BL ; TCF Transcription Factors ; Th17 Cells

The Wnt signaling pathway is conserved in various species from worms to mammals, and plays important roles in cellular proliferation, differentiation, and migration. Wnt stabilizes cytoplasmic beta-catenin and then the accumulated beta-catenin is translocated into the nucleus, where it activates the transcriptional factor T-cell factor (Tcf)/lymphoid enhancer factor (Lef), and thereby stimulates the expression of genes including c-myc, c-jun, fra-1, and cyclin D1. Tight regulation of this response involves post-translational modifications of the components of the Wnt signaling pathway. Phosphorylation, ubiquitination, and sumoylation have been shown to affect the half-life of beta-catenin and the transcriptional activity of Tcf/Lef. The precise spatio-temporal patterns of these multiple modifications determine the driving force of various cellular responses.
Animals ; Binding Sites ; Gene Expression Regulation ; Humans ; Models, Biological ; Protein Binding ; *Protein Processing, Post-Translational ; *Signal Transduction ; TCF Transcription Factors ; *Trans-Activators ; Wnt Proteins/classification/genetics/*metabolism ; beta Catenin

The effects of retinoic acid on the beta-catenin/TCF pathway in cultured porcine tracheobronchial epithelial cells (TBEC) were investigated. After TBEC were treated with retinoic acid at various concentrations, mRNA and protein changes of beta-catenin in cytoplasm, nucleus and whole cell of the TBEC were observed by immunocytochemical stain, RT-PCR and Western blotting. And the changes of the target gene cyclinD1 of beta-catenin/TCF pathway were also observed. It was found that there was no significant difference in beta-cat mRNA level after retinoic acid treatment. However, the expression of beta-catenin in the whole cell and cytoplasm was elevated with the increase of retinoic acid concentration (P<0. 01). The nuclear protein beta-catenin and target gene cyclinD1 of beta-catenin/TCF pathway was decreased (P<0.05). It was indicated that retinoic acid could increase beta-catenin level of the whole cell protein and decrease nuclear beta-catenin, downregulating beta-cat/TCF signaling activity and reducing target gene cyclinD1 protein level. As a result, retinoic acid can downregulate beta-catenin/TCF pathway in porcine tracheobronchial epithelial cell, suggesting that retinoic acid can inhibit the proliferation and accelerate differentiation of tracheobronchial epithelial cells.
Animals ; Bronchi ; cytology ; metabolism ; Cells, Cultured ; Cyclin D1 ; biosynthesis ; genetics ; Epithelial Cells ; cytology ; metabolism ; RNA, Messenger ; biosynthesis ; genetics ; Signal Transduction ; Swine ; TCF Transcription Factors ; biosynthesis ; genetics ; Trachea ; cytology ; metabolism ; Tretinoin ; pharmacology ; beta Catenin ; biosynthesis ; genetics

This study was purposed to investigate the effect of phenylhexyl isothiocyanate (PHI) on Wnt/β-catenin signaling pathway, histone acetylation, histone methylation and cell apoptosis in Jurkat cell line. The viability of Jurkat cells after treatment with PHI was tested by MTT. Apoptotic rate of Jurkat cells was measured by flow cytometry. The levels of Wnt/β-catenin related proteins including β-catenin, TCF, c-myc, and cyclinD1, histone acetylated H3 and H4, histone methylated H3K9 and H3K4 were detected by Western blot. The results showed that PHI inhibited the cell growth and induced apoptosis in Jurkat cells in time-and dose-dependent manners. Its IC50 at 48 h was about 20 µmol/L. Expression of histone acetylated H3, H4 and histone methylated H3k4 increased after exposure to PHI for 3 h, while histone methylated H3K9 decreased. Expression of β-catenin was not changed after exposure to PHI for 3 h, but expression of β-catenin, and its cell cycle-related genes such as TCF, c-myc and cyclinD1 decreased after exposure to PHI for 7 h. It is concluded that PHI regulates acetylation and methylation of histone, inhibits Wnt/β-catenin signal pathway, and is able to induce apoptosis and inhibits growth of Jurkat cells.
Acetylation ; Acylation ; Cyclin D1 ; metabolism ; Histones ; metabolism ; Humans ; Isothiocyanates ; pharmacology ; Jurkat Cells ; Methylation ; Proto-Oncogene Proteins c-myc ; metabolism ; TCF Transcription Factors ; metabolism ; Wnt Signaling Pathway ; drug effects ; beta Catenin ; metabolism

OBJECTIVETo assess the association between a rs7903146(C/T) polymorphism of TCF7L2 gene and metabolic syndrome (MS), plasma lipoprotein, and plasma adiponectin (PA) in Chinese Korean and Han populations from Yanbian region.

METHODSPolymerase chain reaction and DNA sequencing were used to determine the genotype of rs7903146 in 310 Chinese Korean (190 in case group and 120 in control group) and 344 Chinese Han (255 in case group and 89 in control group). ELIAS was used to test serum insulin (INS) and PA.

RESULTSThe frequency of T allele was higher in ethnic Han compared with ethnic Koreans (0.022 vs. 0.008), lower than that of Europeans (0.279) and Africans (0.257), but similar to those of Beijing Chinese and Japanese. For ethnic Korean Chinese, the frequencies of TT and CT genotypes as well as the T allele in patients with EH were significantly higher than those of the control group (P< 0.01), which also showed an increasing trend for both MS and T2DM groups (P=0.09 and P=0.07, respectively). By contrast, for Chinese Han, the frequencies of genotypes and particular allele in patients with MS, T2DM and EH showed no significant difference from those of the control group. For T2DM, EH, and control groups, PA level of individuals with CT or TT genotypes was significantly higher compared with that of the CC genotype (P< 0.05). The TC and LDL-C levels were significantly higher in T2DM, MS and EH groups compared with those of the control group. The PA level was lower in MS group compared with the control group.

CONCLUSIONThe T allele of SNP rs7903146 of TCF7L2 gene may be a risk factor for EH in Chinese Korean population from Yanbian region. The T allele also affects the PA level; lower PA is a risk factor for MS. The rs7903146 polymorphism showed a racial and ethnic difference.

Adiponectin ; blood ; Base Sequence ; China ; ethnology ; Female ; Humans ; Male ; Metabolic Syndrome ; blood ; enzymology ; genetics ; Molecular Sequence Data ; Polymorphism, Single Nucleotide ; Transcription Factor 7-Like 2 Protein ; genetics ; metabolism

This cohort study was designed to evaluate the association of transcription factor 7-like 2 (TCF7L2) and proglucagon gene (GCG) variants with disordered glucose metabolism and the incidence of type 2 diabetes mellitus (T2DM) in a rural adult Chinese population. A total of 7,751 non-T2DM participants ⋝18 years old genotyped at baseline were recruited. The same questionnaire interview and physical and blood biochemical examinations were performed at both baseline and follow-up. During a median 6 years of follow-up, T2DM developed in 227 participants. After adjustment for potential contributory factors, nominally significant associations were seen between TT genotype and the recessive model of TCF7L2 rs7903146 and increased risk of T2DM [hazard ratio (HR)=4.068, 95% confidence interval (CI): 1.270-13.026; HR=4.051, 95% CI: 1.268-12.946, respectively]. The TT genotype of rs7903146 was also significantly associated with higher fasting plasma insulin level and the homeostasis model assessment of insulin resistance in case of new-onset diabetes. In addition, the TCF7L2 rs290487 TT genotype was associated with abdominal obesity and the GCG rs12104705 CC genotype was associated with both general obesity and abdominal obesity in case of new-onset diabetes.
Adult ; Cohort Studies ; Diabetes Mellitus, Type 2 ; complications ; genetics ; Female ; Humans ; Insulin ; secretion ; Insulin Resistance ; genetics ; Male ; Middle Aged ; Obesity ; complications ; genetics ; Polymorphism, Single Nucleotide ; Proglucagon ; genetics ; Transcription Factor 7-Like 2 Protein ; genetics

Abnormal activation of Wnt signaling pathway is closely related to the occurrence of tumor, and T cell factor 4 (Tcf4 ) and beta-catenin are important signal transmission factors of this pathway. The aim of the present study is to explore the significance and correlation between expression of Tcf4, beta-catenin and secreted frizzled related protein 1(SFRP1), suppressor gene of Wnt signaling pathway, in colorectal carcinoma and their correlations to the clinicopathological factors. The expressions of Tcf4, beta-catenin and SFRP1 were performed with immunohistochemistry staining in 97 cases of primary colorectal carcinoma and 40 cases of normal colorectal mucosa tissues. The results showed that the abnormal expression rates of Tcf4 and beta-catenin in colorectal carcinoma were significantly higher than those in the control groups (P<0.01). The positive rate of SFRP1 was significantly lower than those in the control groups (P<0.01). The abnormal expression rates of Tcf4 and beta-catenin were also related to the lymph node metastasis and Dukes stage (P<0.05). A significant correlation was found between the expressions of SFRP1 and Tcf4, beta-catenin (P<0.05). Overexpression of Tcf4 and beta-catenin was related to poor prognosis (P<0.05). But the survival rates of the group with SFRP1 expressions were higher than those in group without SFRP1 expressions (P<0.05). Cox multifactor regression analysis indicated that Dukes stage, expression of beta-catenin and SFRP1 were independent risk factors of colorectal carcinoma (P<0.05). The results suggested that the abnormal expression of Tcf4 and beta-catenin in colorectal cancer may be related to the reduced or absent expression of SFRP1. beta-catenin accumulation in the nuclei formed complexes with Tcf4 is one of the important molecular switch maintaining colorectal malignant phenotype. The combined detection of these indexes may perform an important role in predicting the progression and prognosis of colorectal cancer, and could provide new molecular targets for gene treatment of colorectal cancer.
Carcinoma ; metabolism ; Colorectal Neoplasms ; metabolism ; Disease Progression ; Humans ; Intercellular Signaling Peptides and Proteins ; metabolism ; Lymphatic Metastasis ; Membrane Proteins ; metabolism ; Phenotype ; Prognosis ; Risk Factors ; Transcription Factor 7-Like 2 Protein ; metabolism ; Wnt Signaling Pathway ; beta Catenin ; metabolism