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Objective:To investigate the role of nuclear transcription factor Gli1/Gli2 of the sonic hedgehog (Shh) signaling pathway in the hepatic epithelial mesenchymal transition (EMT) of biliary atresia mice caused by Rhesus rotavirus (RRV) infection.Methods:The biliary atresia model in mice was generated by RRV infection.Mice were divided into normal group, model group, Gli1 overexpression group, Gli1 shRNA group, Gli2 overexpression group and Gli2 shRNA group.Real-time fluorescence quantitative polymerase chain reaction and Western blot were used to detect the mRNA and protein expressions of regulatory factors for EMT (Snail/Slug) and characteristic cytokines of EMT [Vimentin, α-smooth muscle actin(α-SMA), E-cadherin] in mouse liver tissues.Additionally, hematoxylin-eosin staining and Masson staining were performed to calculate the percentage of liver fibrous tissue expression area.The data were analyzed by One- Way ANOVA and LSD- t test. Results:The relative mRNA expression of Snail, Slug, Vimentin, α-SMA and E-cadherin in Gli2 overexpression group, Gli2 shRNA group and model group were 15.13±3.40, 5.48±0.46, 8.78±1.06, 12.40±2.18 and 3.06±0.53; 3.73±1.16, 5.62±1.75, 3.56±1.06, 3.88±1.16 and 10.51±1.83; 8.13±1.27, 5.32±0.98, 5.05±0.98, 4.02±0.77 and 5.12±1.60.Compared with those of the model group, mRNA levels of Snail, Vimentin and α-SMA were significantly higher in Gli2 overexpression group, while that of E-cadherin was significantly lower( t=4.53, 5.29, 8.12, -2.13; all P<0.05); compared with those of the model group, mRNA levels of Snail and Vimentin in Gli2 shRNA group significantly decreased, while that of E-cadherin significantly increased( t=-2.86, -2.12, 5.62; all P<0.05). In Gli2 overexpression group, Gli2 shRNA group and model group, the protein levels of Snail, Slug, Vimentin, α-SMA and E-cadherin were 2.02±0.39, 0.31±0.08, 0.95±0.17, 1.07±0.17 and 0.42±0.06; 0.53±0.13, 0.40±0.18, 0.20±0.04, 0.28±0.07 and 1.09±0.31; 0.70±0.15, 0.42±0.22, 0.64±0.13, 0.81±0.11 and 0.42±0.09.Compared with those of the model group, protein levels of Snail, Vimentin and α-SMA were significantly higher in Gli2 overexpression group( t=12.71, 4.28, 3.70; all P<0.05); compared with those of the model group, protein levels of Vimentin and α-SMA in Gli2 shRNA group significantly decreased, while that of E-cadherin significantly increased( t=-6.14, -7.57, 5.96; all P<0.05). However, no significant change trend were detected in expression levels of characteristic cytokines of EMT between Gli1 overexpression group and Gli1 shRNA group.The area percentage of liver fiber expression in normal group, model group, Gli1 overexpression group, Gli1 shRNA group, Gli2 overexpression group and Gli2 shRNA group were (1.03±0.58)%, (33.02±11.39)%, (39.81±5.67)%, (26.06±1.29)%, (49.81±8.57)% and (17.55±0.66)%, respectively.Besides, in terms of percentage of area expressed in liver fiber tissue, the Gli2 overexpression group and Gli2 shRNA group were statistically significant compared with the model group( t=3.21, -2.96; all P<0.05), while the Gli1 overexpression group and Gli1 shRNA group were not statistically significant compared with the model group (all P>0.05). Conclusions:The Shh signaling pathway plays an important role in liver fibrosis in mice with biliary atresia.Gli2, a key transcription factor of Shh signaling pathway, can significantly regulate liver EMT process in mice with biliary atresi.
ABSTRACT
OBJECTIVES@#Silence of SET domain containing lysine methyltransferase 7 (SET7) alleviates myocardial tissue injury caused by ischemia-reperfusion. But the effects of SET7 on angiotensin II (Ang II)-induced myocardial fibroblast proliferation and the collagen synthesis are not clear. The purpose of this study was to explore the effect of SET7 on the proliferation and collagen synthesis of myocardial fibroblasts and its mechanisms.@*METHODS@#Myocardial fibroblasts were isolated and identified by immunofluorescence. Myocardial fibroblasts were randomly divided into 4 groups: a control group (cells were normally cultured), an Ang II group (cells were treated with 100 nmol/L Ang II for 24 h), a siCtrl group (cells were transfected with siRNA control and were then treated with 100 nmol/L Ang II for 24 h), and a siSET7 group (cells were transfected with siRNA SET7 and were then treated with 100 nmol/L Ang II for 24 h). Cell counting kit-8 (CCK-8) and 5-ethynyl-2'-deoxyuridine (EdU) assay were used to evaluate cell proliferation. Real-time PCR was used to detect the mRNA levels of SET7, collagen I, collagen III, and α-smooth muscle actin (α-SMA). Western blotting was used to detect the protein expression of SET7, collagen I, collagen III, α-SMA, sonic hedgehog (Shh), ptched1 (Ptch1), and glioma-associated oncogene homolog 1 (Gli1).@*RESULTS@#Fluorescence microscopy showed positive vimentin staining, and myocardial fibroblasts were in good condition. As compared to the control group, the mRNA and protein levels of SET7 in the Ang II group were significantly upregulated; cell proliferation rate and EdU fluorescence intensity in the Ang II group were significantly increased; the mRNA and protein levels of collagen I, collagen III, and α-SMA were significantly upregulated (all @*CONCLUSIONS@#Silence of SET7 gene inhibits Ang II-induced proliferation and collagen synthesis of myocardial fibroblasts. Shh signaling pathway may be involved in this process.
Subject(s)
Angiotensin II/pharmacology , Cell Proliferation , Cells, Cultured , Collagen/genetics , Fibroblasts , Hedgehog ProteinsABSTRACT
Sonic Hedgehog (SHH) signaling pathway participates in the regulation of various organs and growth of tissue cells, maintains normal function and structure in the development of embryogenesis, however, SHH signaling pathway is in a state of inhibition. Meanwhile, the abnormal regulation of SHH signaling pathway plays an important role in the occurrence, development and drug resistance of leukemia. The mechanism of SHH signaling pathway in leukemia is similar to the solid tumor. With the further understanding of SHH signaling pathway, there are many antitumor drugs targeting SHH signaling pathway. The targeting inhibitors targeted SHH signaling pathway will become a new method for the treatment of leukemia. This paper reviews the application of the inhibitors targeting SHH signaling pathway in leukemia.
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Sonic hedgehog(Shh) is a member of the hedgehog family in vertebrate. The Shh signaling pathway is mainly composed of a secreted glycoprotein, named Shh, two transmembrane proteins (Ptch and Smo) and the downstream transcription factor family Glis. It plays a vital role in the embryo development, especially in the neuronal system. Recent study have demonstrated that the Shh pathway is closely associated with the tumorigenesis of various tumors. Glioma, the most common malignant brain tumor of humans, is characterized by the rapid proliferation, infiltrative growth and high rate of relapse, and it is one of the brain tumors with poorest prognosis. Abnormal activation of multiple signaling pathways has been known to enhance the proliferation ability of glioma cells. Moreover, glioma is composed of various tumor cells and the glioma stem cells were endowed with the ability of self-renewal and unlimited proliferation, which plays a key role in the tumorigenesis, progress and relapse. Evidence has been found that Shh signaling pathway is closely assoicated with tumorigenesis of glioma. Herein we review the current knowledge on the components of Shh signaling pathway and its role in the tumorigenesis of glioma and glioma stem cells.
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Sonic Hedgehog (SHH) signaling pathway not only plays key roles in embryonic development,but also functions in postnatal development and maintenance of tissue/organ integrity and function.In recent years,it has been found that the SHH signaling pathway was abnormally activated in some lung diseases,which suggested that the SHH signaling pathway may play a part in the development of some lung diseases.This article reviewed the potential role of SHH signaling pathway on the embryonic lung development and lung diseases.
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Background and purpose: It was reported that Sonic Hedgehog (SHH) signaling pathway was involved in carcinogenesis and progression of various tumor types. This study was designed to observe the expression of Shh and Gli2 in SHH signaling pathway in hepatocellular carcinoma (HCC) and to study the relationship between the expression of Shh and Gli2 and different clinicopathlogical characteristics, and further to explore the clinical significance. Methods: We studied 30 HCC tissues and 10 normal liver tissue slices using immunochemistry for the expression of Shh and Gli2, 10 fresh HCC tissues, adjacent-tumor tissues and 2 HCC cell lines HepG2, Huh7 by using RT-PCR for the mRNA expression of Shh and Gli2. Results: Immunochemistry showed in 30 HCC tissue slices,the positive ratios of the components of SHH signaling pathway Shh, Gli2 were 63.3% (19/30) and 66.7% (20/30), respectively. Expression of Gli2 was significantly correlated with the pathological grade and the tumor invasion in hepatic portal vein (P=0.017 and P=0.024). Shh and Gli2 did not express in normal liver tissue. RT-PCR showed Shh and Gli2 were detected as positive in both HCC tissues and lines. The expressions of Shh mRNA and Gli2 mRNA were higher in HCC than in adjacent-tumor tissues (P<0.05). The expressions of Shh mRNA and Gli2 mRNA were higher in Huh7 than in HepG2 cell lines, but no significant difference was found between them (P>0.05). Conclusion: The expressions of Shh and Gli2 were elevated in HCC, which indicated that SHH signaling pathway may be involved in human HCC carcinogenesis. The study may be useful for treatment of HCC.
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The effects of Sonic hedgehog (Shh) signaling pathway activation on S-type neuroblastoma (NB) cell lines and its role in NB tumorigenesis were investigated. Immunohistochemistry was used to detect the expression of Shh pathway components-- Patchedl (PTCH1) and Glil in 40 human primary NB samples. Western blotting and RT-PCR were used to examine the protein expression and mRNA levels of PTCH1 and Glil in three kinds of S-type NB cell lines (SK-N-AS, SK-N-SH and SHEPI), re-spectively. Exogenous Shh was administrated to activate Shh signaling pathway while cyclopamine was used as a selective antagonist of Shh pathway. S-type NB cell lines were treated with different concen-trations of Shh or/and cyclopamine for different durations. Cell viability was measured by using MTT method. Apoptosis rate and cell cycle were assayed by flow cytometry. The xenograft experiments were used to evaluate the role of Shh pathway in tumor growth in immunodeficient mice. High-level expres-sion of PTCH1 and Gill was detected in both NB samples and S-type NB cell lines. Cyclopamine de-creased the survival rate of the three cell lines while Shh increased it, and the inhibition effects of cyclopaminc could be partially reversed by shh pre-treatment. Cyclopamine induced the cell apoptosis and the cell cycle arrest in G0/G1 phase, while Shh induced the reverse effects and could partially pre-vent effects of cyclopamine. Cyclopamine could also inhibit the growth of NB in vivo. Our studies re-vealed that activation of the Shh pathway is important for survival and proliferation of S-type NB cells in vivo and in vitro through affecting cell apoptosis and cell cycle, suggesting a new therapeutic ap-proach to NB.