Genetic analysis of a child with Pitt-Hopkins syndrome due to a novel variant of TCF4 gene derived from low percentage maternal mosaicism / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic etiology of a child with Pitt-Hopkins syndrome.@*METHODS@#A child who had presented at the Medical Genetics Center of Gansu Provincial Maternal and Child Health Care Hospital on February 24, 2021 and his parents were selected as the study subjects. Clinical data of the child was collected. Genomic DNA was extracted from peripheral blood samples of the child and his parents and subjected to trio-whole exome sequencing (trio-WES). Candidate variant was verified by Sanger sequencing. Karyotype analysis was also carried out for the child, and her mother was subjected to ultra-deep sequencing and prenatal diagnosis upon her subsequent pregnancy.@*RESULTS@#The clinical manifestations of the proband included facial dysmorphism, Simian crease, and mental retardation. Genetic testing revealed that he has carried a heterozygous c.1762C>T (p.Arg588Cys) variant of the TCF4 gene, for which both parents had a wild-type. The variant was unreported previously and was rated as likely pathogenic based on the guidelines of the American College of Medical Genetics and Genomics (ACMG). Ultra-deep sequencing indicated that the variant has a proportion of 2.63% in the mother, suggesting the presence of low percentage mosaicism. Prenatal diagnosis of amniotic fluid sample suggested that the fetus did not carry the same variant.@*CONCLUSION@#The heterozygous c.1762C>T variant of the TCF4 gene probably underlay the disease in this child and has derived from the low percentage mosaicism in his mother.

Optimizations of an ELISA-like high-throughput screening assay for the discovery of β-catenin/TCF4 interaction antagonists / 生物工程学报

In canonical Wnt/β-catenin signaling pathway, β-catenin/TCF4 (T-cell factor 4) interaction plays an important role in the pathogenesis and development of non-small cell lung cancer (NSCLC), and it is tightly associated with the proliferation, chemoresistance, recurrence and metastasis of NSCLC. Therefore, suppressing β-catenin/TCF4 interaction in Wnt/β-catenin signaling pathway would be a new therapeutic avenue against NSCLC metastasis. In this study, considering the principle of enzyme-linked immunosorbent assay (ELISA), an optimized high-throughput screening (HTS) assay was developed for the discovery of β-catenin/TCF4 interaction antagonists. Subsequently, this ELISA-like screening assay was performed using 2 μg/mL GST-TCF4 βBD and 0.5 μg/mL β-catenin, then a high Z' factor of 0.83 was achieved. A pilot screening of a natural product library using this ELISA-like screening assay identified plumbagin as a potential β-catenin/TCF4 interaction antagonist. Plumbagin remarkably inhibited the proliferation of A549, H1299, MCF7 and SW480 cell lines. More importantly, plumbagin significantly suppressed the β-catenin-responsive transcription in TOPFlash assay. In short, this newly developed ELISA-like screening assay will be vital for the rapid screening of novel Wnt inhibitors targeting β-catenin/TCF4 interaction, and this interaction is a potential anticancer target of plumbagin in vitro.

Genetic analysis of a case with Pitt-Hopkins syndrome due to variant of TCF4 gene / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic basis of a patient presenting with dysmorphism, intellectual disability, psychomotor delay and hypoplasia of corpus callosum by using next generation sequencing.@*METHODS@#Genomic DNA was extracted from peripheral blood samples of the patient and his family members and subjected to exome sequencing. Suspected variants were verified with Sanger sequencing.@*RESULTS@#The patient was found to carry a heterozygous c.1357delAinsGGA variant in exon 11 of the TCF4 gene, which was verified as de novo by Sanger sequencing. The variant may result in a truncated protein and affect its function.@*CONCLUSION@#The heterozygous c.1357delAinsGGA variant the TCF4 gene probably underlies the disease in the proband.

Genetic analysis of a rare case of Pitt-Hopkins syndrome due to partial deletion of TCF4 gene / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic basis for a child featuring delayed intellectual development.@*METHODS@#The child and his parents were subjected to conventional G-banding karyotyping and single nucleotide polymorphism array (SNP-array) analysis. Suspected copy number variations (CNVs) were verified in both parents.@*RESULTS@#No karyotypic abnormality was found with the child and his parents. SNP-array results for both parents were normal. The child was found to harbor a de novo 172 kb deletion at 18q21.2 with a physical position of 52 957 042-53 129 237. The deletion only involved one OMIM gene, namely TCF4, resulting in removal of its exons 6 to 8.@*CONCLUSION@#The SNP-array assay has facilitated with the diagnosis of this child. Deletion of 18q21.2 region probably accounts for the Pitt-Hopkins syndrome (PTHS) in this patient.

Expression of e-cadherin and wnt pathway proteins betacatenin, apc, tcf-4 and survivin in gastric adenocarcinoma: clinical and pathological implication / Expressão da e-caderina e das proteínas da via de sinalização wnt betacatenina, apc, tcf-4 e survivina no adenocarcinoma gástrico: implicações clínica e patológica

ABSTRACT Background: Gastric cancer is the fifth most frequent cancer and the third most common cause of cancer-related deaths worldwide.It has been reported that Wnt/ betacatenin pathway is activated in 30-50% of these tumors. However,the deregulation of this pathway has not been fully elucidated. Aim: To determine the expression of E-cadherin, betacatenin, APC, TCF-4 and survivin proteins in gastric adenocarcinoma tissues and correlate with clinical and pathological parameters. Method: Seventy-one patients with gastric adenocarcinoma undergoing gastrectomy were enrolled. The expression of E-cadherin, betacatenin, APC, TCF-4 and survivin proteins was detected by immunohistochemistryand related to the clinical and pathological parameters. Results: The expression rates of E-cadherin in the membrane was 3%; betacatenin in the cytoplasm and nucleus were 23,4% and 3,1% respectively; APC in the cytoplasm was 94,6%; TCF-4 in the nucleus was 19,4%; and survivin in the nucleus 93,9%. The expression rate of E-cadherin was correlated with older patients (p=0,007), while betacatenin with tumors <5 cm (p=0,041) and APC with proximal tumors (p=0,047). Moreover, the expression of TCF-4 was significantly higher in the diffuse type (p=0,017) and T4 tumors (p=0,002). Conclusion: The Wnt/betacatenin is not involved in gastric carcinogenesis. However, the high frequency of survivin allows to suggest that other signaling pathways must be involved in the transformation of gastric tissue.

RESUMO Racional: O câncer gástrico encontra-se entre as principais neoplasias malignas do mundo sendo o quinto mais incidente e o terceiro em relação ao índice de mortalidade. Acredita-se que a via Wnt/betacatenina esteja ativada em 30-50% desses tumores, porém a desregulação dela ainda não está completamente esclarecida. Objetivo: Avaliar a imunoexpressão das proteínas E-caderina, betacatenina, APC, TCF-4 e survivina em tecidos de adenocarcinoma gástrico e correlacioná-las com as variáveis clínicas dos doentes e anatomopatológicas do tumor. Método: Foram coletados os dados clínicos e anatomopatológicos dos prontuários de 71 doentes com adenocarcinoma gástrico submetidos à gastrectomia. O material obtido na operação foi submetido à análise imunoistoquímica e a frequência da expressão de cada proteína pôde ser analisada de acordo com a sua localização na célula e relacionada com as variáveis clinicopatológicas. Resultados: A graduação percentualda expressão e da localização das proteínas foi a seguinte: E-caderina em 3% na membrana; betacatenina em 23,4% no citoplasma e 3,1% no núcleo; APC em 94,6% no citoplasma; TCF-4 em19,4% no núcleo; e survivina em 93,9% no núcleo. Houve relação entre expressão da proteína E-caderina com a idade mais avançada (p=0,007); betacatenina com tumores <5 cm de diâmetro (p=0,041);APC com tumores proximais (p=0,047); e TCF-4 com tipo difuso da classificação de Lauren (p=0,017) e com o grau de penetração tumoral (p=0,002). Conclusão: A via Wnt/betacatenina não está envolvida na carcinogênese gástrica. Porém, a frequência elevada de survivina permite sugerir que outras vias sinalizadoras devam estar envolvidas na transformação do tecido gástrico.

Fibroblast growth factor-1 inhibits Wnt/β-catenin pathway during adipogenesis / 中南大学学报(医学版)

OBJECTIVE@#To determine the time course and potential mechanism of fibroblast growth factor-1 (FGF-1) in the regulation of adipogenesis.
@*METHODS@#We cultured human Simpson-Golabi-Behmel syndrome (SGBS) pre-adipocytes with recombinant FGF-1 and harvested cells at various stages prior to and during differentiation; at cell proliferation (D-3), confluence (D0), early (D3), middle (D7) and mature (D14) stages of differentiation. We determined lipid accumulation in mature adipocytes by morphological observation and quantitative measurement of oil red O staining. We also examined the expression of adipogenic genes and related markers involved in the Wnt/β-catenin pathway using quantitative Real-time PCR and Western blot.
@*RESULTS@#Compared to control SGBS cells, treatment with FGF-1 increased lipid accumulation; induced a sustained increase in the mRNA for peroxisome proliferater-activated receptor γ (PPARγ), glyceraldehyde-3-phosphate dehydrogenase (G3PDH), adiponectin and glucose transporter type 4 (GLUT4); and promoted a sustained decrease in expression of markers of the Wnt/β-catenin pathway, β-catenin and transcription factor 4 (TCF4).
@*CONCLUSION@#The adipogenic effects of FGF-1 are apparent throughout the whole priming and differentiation period in human SGBS pre-adipocytes. Furthermore, our results suggest that FGF-1 
promotes adipogenesis, at least in part, via a sustained decrease in activity of the Wnt/β-catenin pathway.

Immunohistochemistry expression of TCF4 protein on carcinoma, adenoma and non neoplastic colorectal mucosa / Expressão imuno-histoquímica da proteína TCF4 no carcinoma, no adenoma e na mucosa não neoplásica colorretal

PURPOSE: To detect and quantify the immunoreactivity of TCF4 protein in colorectal carcinoma, colorectal adenoma and non-neoplasic colorectal epithelium. METHODS: We studied 129 individuals: 40 with colorectal cancer, 52 with colorectal adenoma and 37 with non-neoplastic colorectal epithelium. The colorectal adenoma and carcinoma samples were obtained from patients who underwent surgical procedures, and colonoscopies and samples of non-neoplastic colorectal epithelium were taken from patients who died from cardiovascular diseases, without diseases of the large intestine. Samples of different tissues were included in paraffin blocks, and the immunohistochemical expression of protein TCF4 was analyzed using the technique of tissue microarray (TMA) with polyclonal antibody TCF4. The immunoreactivity was analyzed and classified as positive and negative. RESULTS: The immunohistochemical expression of TCF4 protein was significantly higher (p < 0.01) in colorectal carcinoma than in the non-neoplastic colorectal epithelium and adenoma. There was no difference (p = 0.76) between TCF4 protein immunohistochemical expression in colorectal adenoma and non-neoplastic colorectal tissue. CONCLUSIONS: TCF4 protein showed a more intense expression in colorectal carcinoma than in non-neoplastic colorectal epithelium and adenoma, indicating that this protein is involved in colorectal carcinogenesis. (AU)

OBJETIVOS: Detectar e quantificar a imunoexpressão da proteína TCF4 no carcinoma e no adenoma colorretal e no epitélio colorretal não neoplásico. MÉTODO: Foram estudados 129 indivíduos: 40 com carcinoma colorretal, 52 com adenoma colorretal e 37 com epitélio colorretal não neoplásico. Os tecidos de adenoma e carcinoma colorretais foram representados por amostras da lesão retirada de doentes submetidos a procedimentos cirúrgicos e colonoscópicos, e as amostras de epitélio colorretal não neoplásico foram retiradas de doentes falecidos por afecções cardiovasculares e sem comprometimento do intestino grosso. As amostras dos diferentes tecidos foram incluídas em blocos de parafina e submetidas ao estudo da imunoexpressão da proteína TCF4 pela técnica do tissue microarray (TMA) com o anticorpo policlonal anti-TCF4. A imunorreatividade foi analisada e classificada como positiva e negativa. RESULTADOS: A imunoexpressão da proteína TCF4 foi significantemente maior (p < 0,01) no carcinoma colorretal do que nos adenomas e no epitélio colorretal não doente. Não houve diferença significante (p = 0,76) entre a imunoexpressão da proteína TCF4 no adenoma colorretal e no epitélio colorretal não doente. CONCLUSÃO: A maior expressão da proteína TCF4 no carcinoma colorretal em relação ao adenoma e ao epitélio não doente sugere que esta proteína possui participação na carcinogênese colorretal. (AU)

Effects of Biejiajian Pills on Wnt signal pathway signal molecules β-catenin/TCF4 complex activities and downstream proteins cyclin D1 and MMP-2 in hepatocellular carcinoma cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the effect of Biejiajian Pills on Wnt signal pathway and the mechanisms underlying its action to suppress the invasiveness of hepatocellular carcinoma.</p><p><b>METHODS</b>HepG2 cells cultured in the serum of rats fed with Biejiajian Pills for 48 h were examined for β-catenin expression using immunofluorescence, β-catenin/TCF4 complex activity with luciferase, and expressions of the downstream proteins cyclin D1 and MMP-2 using qRT-PCR.</p><p><b>RESULTS</b>Biejiajian Pills-treated sera significantly reduced the expressions of cytoplasmic and nuclear β-catenin protein, cyclin D1 and MMP-2 proteins and lowered the activities of β-catenin/TCF4 complex.</p><p><b>CONCLUSION</b>Biejiajian Pills may serve as a potential anti-tumor agent, whose effect might be mediated by inhibiting the Wnt/β-catenin pathway.</p>

Effect of over-expressed miR-155 on inhibiting C2C12 myogenic differentiation / 生物工程学报

To clarify the function and molecular mechanism of miR-155 in myogenic differentiation of C2C12, we constructed adenovirus over-expression vector of miR-155, then C2C12 cells were infected by adenovirus and induced myogenic differentiation. First, we observed the morphology of C2C12 after differentiation. Then the mRNA and protein expressions of myogenic markers (MyoD, MyoG and MyHC) were detected by qPCR and western blotting. Subsequently, the dual luciferase reporter gene assay was carried out to validate putative target gene (TCF4) of miR-155. Meanwhile, mRNA level of TCF4 was analyzed after over-expressing miR-155. The results show that over-expressed miR-155 reduced myotubes formation. Moreover, the mRNA and protein expression of MyoG and MyHC decreased significantly (P < 0.01). Further research demonstrated miR-155 bound the one (4532-4538) of three putative sites (1487-1493,1516-1522, 4532-4583) of TCF4 by luciferase reporter gene assay and the mRNA level of TCF4 decreased notably (P < 0.05). The data suggest that miR-155 inhibited myogenic differentiation of C2C12 through targeted TCF4.

Effect of Radix Astragali on signal transducer and activator of transcription activator-4 and its mRNA expression in a rat model of asthma / 中华儿科杂志

<p><b>OBJECTIVE</b>To study the effect of Radix Astragali (RA) on the expression of signal transducer and activator of transcription-4 (STAT4) and its mRNA in the bronchus of a rat model of asthma.</p><p><b>METHODS</b>Forty male SD rats were randomly divided into four groups: the control group, asthma group, high dosage of RA group and low dosage of RA group. In the experiment, the rat model of asthma was established by the ovalbumin (OVA) challenge methods. The lung tissue was gainedfrom the left lung, bronchoalveolar lavage fluid (BALF) was gained from the right lung. The eosinophils (EOS) numbers and differentiated cell numbers in BALF were counted by different counting fluids; the protein expressions of STAT4 were detected by immunohistochemistry; the mRNA expressions of STAT4 were detected by in situ hybridization.</p><p><b>RESULTS</b>(1) In the BALF of the asthma group, the absolute numbers of EOS, the ratios of EOS to the total cell numbers (EOS%) of asthma group [(35.81 +/- 7.30) x 10(7)/L, (8. 20 +/- 1.75)%] were all significantly higher than those of the control group [(1.51 +/- 1.04) x 10(7)/L, (0.70 +/- 0.48)%] (P < 0.01); the total cell numbers in BALF, the absolute numbers of EOS and EOS% of RA groups [(14.89 +/- 2.35) x 10(7)/L, (4.70 +/- 0.82)%; (10.98 +/- 1.81) x 10(7)/L, (3.56 +/- 0.53)%] were all significantly lower than those of asthma group (P < 0.01); (2) The concentration of IL-4 in BALF of asthma group (25.70 +/- 7.36) was significantly higher than that of the control group (8.55 +/- 2.97) (P < 0.01); the concentration of IL-4 of BALF of RA groups [(31.89 +/- 5.46), (35.26 +/- 6.03)] was significantly lower than that of asthma group (P < 0.01); the concentration of IL-12 of BALF of asthma group (16.10 +/- 3.38) was significantly lower than that of the control group (42.33 +/- 9.66) (P < 0.01); the concentration of IL-12 of BALF of the RA groups [(31.89 +/- 5.46), (35.26 +/- 6.03)] was significantly higher than that of the asthma group (P < 0.01); (3) Immunohistochemistry and in situ hybridization showed that the protein content of STAT4 and the STAT4 mRNA expression around the bronchus of asthma group [(0.096 +/- 0.012), (0.098 +/- 0.011)] were lower than those of the control group [(0.216 +/- 0.034), (0.228 +/- 0.032)], while those of RA groups [(0.176 +/- 0.012), (0.185 +/- 0.023); (0.183 +/- 0.011), (0.201 +/- 0.019)] were all significantly higher than that of the asthma group (P < 0.01), the airway smooth muscle cells, the pulmonary arterial smooth muscle cells and endothelial cells were the chief expression cells; (4) the STAT4 and the STAT4mRNA expression around the bronchus had positive correlation with the concentration of IL-12 in BALF while had negative correlation with the concentration of IL-4, absolute numbers of EOS in BALF.</p><p><b>CONCLUSIONS</b>RA has an inhibitory effect on airway inflammation cells infiltration such as EOS, it raises the STAT4 protein and its mRNA expression in the airway smooth muscle cells, the pulmonary arterial smooth muscle cells and endothelial cells, and the key mechanism may be that the IL-12 composition is increased.</p>

Effects of NGX6 on the transcriptional activation of beta-catenin/TCF/LEF in Wnt/beta-catenin signal pathway / 中南大学学报(医学版)

OBJECTIVE@#To explore the effects of NGX6 on the transcriptional activation of beta-catenin/TCF/LEF in Wnt/beta-catenin signal pathway, and to identify the role of NGX6 in Wnt signal pathway.@*METHODS@#The eukaryotic expression vector pcDNA3.1(+)-beta-catenin (WT) was constructed. pcDNA3.1(+)-beta-catenin (WT) and pCMV-myc-NGX6 were cotransfected to COS-7 and the transcriptional activity of TCF/LEF was detected by TCF-4 luciferase report system. Without extro-genous beta-catenin, pCMV-myc-NGX6 was transfected alone to COS-7 and colon cancer cell line SW620, and the transcriptional activity of TCF/LEF was detected by TCF-4 luciferase report system, and then the expression of nucleus beta-catenin and TCF-4 was detected by Western blot.@*RESULTS@#The eukaryotic expression vector pcDNA3.1(+)-beta-catenin (WT) was successfully constructed. The activation of TCF-4 luciferase report gene in the cotransfection group in COS-7 was less than that in NGX6 alone transfection group (P<0.05). The activation of TCF-4 luciferase report gene in NGX6 alone transfection group without extro-genous beta-catenin was less than that in pCMV-myc transfection group in COS-7 and SW620. The expression of beta-catenin and TCF-4 was decreased after the NGX6 transfection in COS-7 and SW620 cells.@*CONCLUSION@#NGX6 can inhibit the transcriptional activation of beta-catenin/TCF/LEF in Wnt signal pathway by its negative regulation in the nuclear translocation of beta-catenin.