目的观察遗传性视网膜色素变性RCS大鼠病程发展中视网膜边缘生发区Shh/Ptc信号途径改变及其与该区细胞增殖能力变化的关系。方法RCS大鼠按出生后病程变化分为15、30、60、90 d 4组(免疫组化每组4只,PCR每组3只),以同龄含色素的正常大鼠(...目的观察遗传性视网膜色素变性RCS大鼠病程发展中视网膜边缘生发区Shh/Ptc信号途径改变及其与该区细胞增殖能力变化的关系。方法RCS大鼠按出生后病程变化分为15、30、60、90 d 4组(免疫组化每组4只,PCR每组3只),以同龄含色素的正常大鼠(Long-Evan’s大鼠)作为正常对照。视网膜组织切片DAPI荧光染色观察外核层(outernuclear layer,ONL)厚度的变化;视网膜细胞增殖标记Ki67免疫荧光染色观察视网膜边缘生发区细胞增殖能力的变化;荧光定量PCR检测视网膜边缘生发区Shh/Ptc信号途径中关键分子Shh、Ptc1、Smo和Gli1 mRNA表达水平。结果①RCS大鼠从第15天开始,随着年龄的增加视网膜ONL逐渐变薄,第90天ONL几乎消失。②正常对照组大鼠视网膜边缘生发区Ki67阳性细胞较少,与同龄正常对照组大鼠相比,出生30、60 d组大鼠Ki67阳性细胞数均显著增多(P<0.05);大鼠各年龄组间比较,60 d组Ki67阳性细胞数明显增多(P<0.01)。③60 d组大鼠视网膜边缘生发区Shh、Ptc1、Smo和Gli1mRNA表达水平明显上调。结论出生后60 d RCS大鼠视网膜边缘生发区Shh/Ptc信号途径的激活,可能刺激了该部位细胞短期的增殖。展开更多
Objective: To investigate the changes and mechanism of angiogenesis in myocardium induced by transplantation of the sonic hedgehog (shh) gene transfected in bone marrow mesenchymal stem cells (BMMSC) after myocardial ...Objective: To investigate the changes and mechanism of angiogenesis in myocardium induced by transplantation of the sonic hedgehog (shh) gene transfected in bone marrow mesenchymal stem cells (BMMSC) after myocardial infarction. Methods: A rat model of acute myocardial infarction was made by coronary artery ligation. The rats were randomly divided into five groups of 40 rats each. These were further subdivided into groups of 10 rats. The peripheral regions of the infarcts were injected with either BMMSCSHH (transfection group), equivalent BMMSC (cell only group), BMMSC and pcDNA3.1-Shh DNA mixture (mixture group), pcDNA3.1-shh DNA alone (gene only group), or equal volumes of low-sugar DMEM medium (control group). One, two, four, and eight weeks after transplantation, specimens were harvested from the transplantation site to determine the expression of SHH signaling pathway downstream genes Ptc1, Gli-2, COUP-TF II, angiogenesis promoting factor VEGF, and Ang-1 using RT-PCR. Results: Seven days after transplantation, the expression of SHH signaling pathway downstream genes, Ptc1, Gli-2, and COUP-TF II was significantly more pronounced in the transfection group than in the control group, cell only group, gene only group, or mixture group (Ptc1: P P P < 0.05, and P COUP-TF II: P P P P Gli-2: P P P < 0.05, and P < 0.05, respectively). The expression of angiogenesis-promoting genes Vegf and Ang-1 was significantly more pronounced than in the control group, cell only group, or gene only group (Vegf: P P P Ang-1: P P P < 0.05, respectively). Conclusion: Transplantation of the shh-gene-transfected BMMSCs to the peripheral regions of myocardial infarcts promoted angiogenesis by upregulating downstream gene expression.展开更多
Medulloblastoma is the most common malignant pediatric brain tumor. Some are thought to originate from cerebellar granule neuron progenitors （CGNPs） that fail to undergo normal cell cycle exit and differentiation. T...Medulloblastoma is the most common malignant pediatric brain tumor. Some are thought to originate from cerebellar granule neuron progenitors （CGNPs） that fail to undergo normal cell cycle exit and differentiation. The contribution of microRNAs to the initiation and progression of medulloblastoma remains poorly understood. Increased expression of the miR-183-96-182 cluster of microRNAs has been noted in several aggressive sub- groups. We identified that expression of miR-183-96-182 was higher in medulloblastomas with Pten gene loss in the background of the activated sonic hedgehog （Shh） signaling pathway. Ectopic miR-183-96-182 expression in CGNPs synergized with exogenous Shh to increase proliferation and its role depended on hedgehog signaling ac- tivation. Our findings suggest a new microRNA cluster, the miR-183-96-182, functionally collaborates with the Shh signaling pathway in the development of medulloblastomas in mice.展开更多
Odontogenic keratocysts(OKCs) are common cystic lesions of odontogenic epithelial origin that can occur sporadically or in association with naevoid basal cell carcinoma syndrome(NBCCS). OKCs are locally aggressive, ca...Odontogenic keratocysts(OKCs) are common cystic lesions of odontogenic epithelial origin that can occur sporadically or in association with naevoid basal cell carcinoma syndrome(NBCCS). OKCs are locally aggressive, cause marked destruction of the jaw bones and have a propensity to recur. PTCH1 mutations(at ～80%) are frequently detected in the epithelia of both NBCCS-related and sporadic OKCs, suggesting that PTCH1 inactivation might constitutively activate sonic hedgehog(SHH) signalling and play a major role in disease pathogenesis. Thus, small molecule inhibitors of SHH signalling might represent a new treatment strategy for OKCs. However, studies on the molecular mechanisms associated with OKCs have been hampered by limited epithelial cell yields during OKC explant culture. Here, we constructed an isogenic PTCH1^(R135 X/+) cellular model of PTCH1 inactivation by introducing a heterozygous mutation, namely, c.403 C>T(p.R135 X), which has been identified in OKC patients, into a human embryonic stem cell line using the clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated 9(Cas9) system. This was followed by the induction of epithelial differentiation. Using this in vitro isogenic cellular model, we verified that the PTCH1 R135 X/+heterozygous mutation causes ligand-independent activation of SHH signalling due to PTCH1 haploinsufficiency. This activation was found to be downregulated in a dose-dependent manner by the SHH pathway inhibitor GDC-0449. In addition, through inhibition of activated SHH signalling, the enhanced proliferation observed in these induced cells was suppressed, suggesting that GDC-0449 might represent an effective inhibitor of the SHH pathway for use during OKC treatment.展开更多
文摘目的观察遗传性视网膜色素变性RCS大鼠病程发展中视网膜边缘生发区Shh/Ptc信号途径改变及其与该区细胞增殖能力变化的关系。方法RCS大鼠按出生后病程变化分为15、30、60、90 d 4组(免疫组化每组4只,PCR每组3只),以同龄含色素的正常大鼠(Long-Evan’s大鼠)作为正常对照。视网膜组织切片DAPI荧光染色观察外核层(outernuclear layer,ONL)厚度的变化;视网膜细胞增殖标记Ki67免疫荧光染色观察视网膜边缘生发区细胞增殖能力的变化;荧光定量PCR检测视网膜边缘生发区Shh/Ptc信号途径中关键分子Shh、Ptc1、Smo和Gli1 mRNA表达水平。结果①RCS大鼠从第15天开始,随着年龄的增加视网膜ONL逐渐变薄,第90天ONL几乎消失。②正常对照组大鼠视网膜边缘生发区Ki67阳性细胞较少,与同龄正常对照组大鼠相比,出生30、60 d组大鼠Ki67阳性细胞数均显著增多(P<0.05);大鼠各年龄组间比较,60 d组Ki67阳性细胞数明显增多(P<0.01)。③60 d组大鼠视网膜边缘生发区Shh、Ptc1、Smo和Gli1mRNA表达水平明显上调。结论出生后60 d RCS大鼠视网膜边缘生发区Shh/Ptc信号途径的激活,可能刺激了该部位细胞短期的增殖。
文摘Objective: To investigate the changes and mechanism of angiogenesis in myocardium induced by transplantation of the sonic hedgehog (shh) gene transfected in bone marrow mesenchymal stem cells (BMMSC) after myocardial infarction. Methods: A rat model of acute myocardial infarction was made by coronary artery ligation. The rats were randomly divided into five groups of 40 rats each. These were further subdivided into groups of 10 rats. The peripheral regions of the infarcts were injected with either BMMSCSHH (transfection group), equivalent BMMSC (cell only group), BMMSC and pcDNA3.1-Shh DNA mixture (mixture group), pcDNA3.1-shh DNA alone (gene only group), or equal volumes of low-sugar DMEM medium (control group). One, two, four, and eight weeks after transplantation, specimens were harvested from the transplantation site to determine the expression of SHH signaling pathway downstream genes Ptc1, Gli-2, COUP-TF II, angiogenesis promoting factor VEGF, and Ang-1 using RT-PCR. Results: Seven days after transplantation, the expression of SHH signaling pathway downstream genes, Ptc1, Gli-2, and COUP-TF II was significantly more pronounced in the transfection group than in the control group, cell only group, gene only group, or mixture group (Ptc1: P P P < 0.05, and P COUP-TF II: P P P P Gli-2: P P P < 0.05, and P < 0.05, respectively). The expression of angiogenesis-promoting genes Vegf and Ang-1 was significantly more pronounced than in the control group, cell only group, or gene only group (Vegf: P P P Ang-1: P P P < 0.05, respectively). Conclusion: Transplantation of the shh-gene-transfected BMMSCs to the peripheral regions of myocardial infarcts promoted angiogenesis by upregulating downstream gene expression.
文摘Medulloblastoma is the most common malignant pediatric brain tumor. Some are thought to originate from cerebellar granule neuron progenitors （CGNPs） that fail to undergo normal cell cycle exit and differentiation. The contribution of microRNAs to the initiation and progression of medulloblastoma remains poorly understood. Increased expression of the miR-183-96-182 cluster of microRNAs has been noted in several aggressive sub- groups. We identified that expression of miR-183-96-182 was higher in medulloblastomas with Pten gene loss in the background of the activated sonic hedgehog （Shh） signaling pathway. Ectopic miR-183-96-182 expression in CGNPs synergized with exogenous Shh to increase proliferation and its role depended on hedgehog signaling ac- tivation. Our findings suggest a new microRNA cluster, the miR-183-96-182, functionally collaborates with the Shh signaling pathway in the development of medulloblastomas in mice.
基金supported by the National Natural Science Foundation of China (81671006, 81300894)Beijing Natural Science Foundation (7172238)
文摘Odontogenic keratocysts(OKCs) are common cystic lesions of odontogenic epithelial origin that can occur sporadically or in association with naevoid basal cell carcinoma syndrome(NBCCS). OKCs are locally aggressive, cause marked destruction of the jaw bones and have a propensity to recur. PTCH1 mutations(at ～80%) are frequently detected in the epithelia of both NBCCS-related and sporadic OKCs, suggesting that PTCH1 inactivation might constitutively activate sonic hedgehog(SHH) signalling and play a major role in disease pathogenesis. Thus, small molecule inhibitors of SHH signalling might represent a new treatment strategy for OKCs. However, studies on the molecular mechanisms associated with OKCs have been hampered by limited epithelial cell yields during OKC explant culture. Here, we constructed an isogenic PTCH1^(R135 X/+) cellular model of PTCH1 inactivation by introducing a heterozygous mutation, namely, c.403 C>T(p.R135 X), which has been identified in OKC patients, into a human embryonic stem cell line using the clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated 9(Cas9) system. This was followed by the induction of epithelial differentiation. Using this in vitro isogenic cellular model, we verified that the PTCH1 R135 X/+heterozygous mutation causes ligand-independent activation of SHH signalling due to PTCH1 haploinsufficiency. This activation was found to be downregulated in a dose-dependent manner by the SHH pathway inhibitor GDC-0449. In addition, through inhibition of activated SHH signalling, the enhanced proliferation observed in these induced cells was suppressed, suggesting that GDC-0449 might represent an effective inhibitor of the SHH pathway for use during OKC treatment.
