Summary: To investigate role of Notch1-3 in hyperoxia-induced lung injury in newborn rat exposed to 85% O 2, SD rat litters born on the 22th day were randomly divided into two groups: room air group and hyperoxia gro...Summary: To investigate role of Notch1-3 in hyperoxia-induced lung injury in newborn rat exposed to 85% O 2, SD rat litters born on the 22th day were randomly divided into two groups: room air group and hyperoxia group. The animals were sacrificed 1, 4, 7, 10, 14 and 21 days after continued exposure to oxygen (n=40, oxygen>0.85) or room air (n=40). 6 rats each group were used to assess lung histological changes by HE staining and expression of Notch in lungs by immunohistochemistry. Total RNA was extracted by Trizol reagent from frozen lung tissues. Notch mRNA were measured by reverse transcription polymerase chain reaction (RT-PCR). Our results showed that 7, 14 and 21 days after O 2 exposure, hyperoxia group showed lung injury characterized by pulmonary edema, hemorrhage and lung development arrest. Positive staining for Notch1, Notch 2 in hyperoxia group was much lower than those in room air group at all time points (P<0.01, P<0.05), but compared with the controls, the hyperoxia group showed higher expression of Notch3 (P>0.05). Immunostained cells were typically airways epithelia, alveolar epithelial and inflammatory cells, and fibroblasts in hyperoxia group (P<0.01). Notch mRNA levels showed similar change as protein level (P< 0.01). It is concluded that the prolonged exposure to 85 % O 2 resulted in abnormal expression of Notch receptors, which might contribute to the pathogenesis of hyperoxia-induced lung injury in newborn rats. The decreased inhibition of Notch1 might be one of the protective reaction and major mechanisms for proliferation/differentiation of type Ⅱ alveolar epithelial cells. The up-regulation of Notch3 activity might result in the lung development arrest of the newborn rats.展开更多
AIM:To investigate the role and clinicopathological significance of aberrant expression of Notch receptors and Delta-like ligand-4 (DLL4) in extrahepatic cholangiocarcinoma and gallbladder carcinoma.METHODS:One hundre...AIM:To investigate the role and clinicopathological significance of aberrant expression of Notch receptors and Delta-like ligand-4 (DLL4) in extrahepatic cholangiocarcinoma and gallbladder carcinoma.METHODS:One hundred and ten patients had surgically resected extrahepatic cholangiocarcinoma (CC) and gallbladder carcinoma specimens examined by immunohistochemistry of available paraffin blocks.Immunohistochemistry was performed using anti-Notch receptors 1-4 and anti-DLL4 antibodies.We scored the immunopositivity of Notch receptors and DLL4 expression by percentage of positive tumor cells with cytoplasmic expression and intensity of immunostaining.Coexistent nuclear localization was evaluated.Clinicopatho-logical parameters and survival data were compared with the expression of Notch receptors 1-4 and DLL4.RESULTS:Notch receptor proteins showed in the cytoplasm with or without nuclear expression in cancer cells,as well as showing weak cytoplasmic expression in non-neoplastic cells.By semiquantitative evaluation,positive immunostaining of Notch receptor 1 was detected in 96 cases (87.3%),Notch receptor 2 in 97 (88.2%),Notch receptor 3 in 97 (88.2%),Notch receptor 4 in 103 (93.6),and DLL4 in 84 (76.4%).In addition,coex- istent nuclear localization was noted [Notch receptor 1;18 cases (18.8%),Notch receptor 2;40 (41.2%),Notch receptor 3;32 (33.0%),Notch receptor 4;99 (96.1%),DLL4;48 (57.1%)].Notch receptor 1 expression was correlated with advanced tumor,node,metastasis (TNM) stage (P=0.043),Notch receptor 3 with advanced T stage (P=0.017),tendency to express in cases with nodal metastasis (P=0.065) and advanced TNM stage (P=0.052).DLL4 expression tended to be related to less histological differentiation (P=0.095).Coexistent nuclear localization of Notch receptor 3 was related to no nodal metastasis (P=0.027) and Notch receptor 4 with less histological differentiation (P=0.036),while DLL4 tended to be related inversely with T stage (P=0.053).Coexistent nuclear localization of DLL4 was related to poor survival (P=0.002).CONCLUSION:Aberrant expression of Notch receptors 1 and 3 play a role during cancer progression,and cytoplasmic nuclear coexistence of DLL4 expression correlates with poor survival in extrahepatic CC and gallbladder carcinoma.展开更多
AIM:To investigate the relationship between late SV40 factor(LSF)and Notch signaling in the development and progress of hepatocellular carcinoma(HCC).METHODS:Liver cancer tissue specimens from 25 patients were analyze...AIM:To investigate the relationship between late SV40 factor(LSF)and Notch signaling in the development and progress of hepatocellular carcinoma(HCC).METHODS:Liver cancer tissue specimens from 25 patients were analyzed for Notch-1 and LSF expression by immunohistochemistry.The correlation between expression and the biological effects of Notch-1 and LSF were analyzed using genetic and pharmacological strategies in HCC cell lines and human normal cell lines,including hepatic stellate cells(HSC)and human embryonic kidney epithelial cells(HEK).RESULTS:Immunohistochemistry showed that both Notch-1 and LSF were significantly upregulated in HCC samples(76%,19/25,P<0.0001 and 84%,21/25,P<0.0001,respectively)compared with non-cancer samples.Activation of Notch-1 by exogenous transfection of Notch1 intracellular domain increased LSF expression in HSC and HEK cells to levels similar to those seen in HepG2 cells.Furthermore,blocking Notch-1 activation with aγ-secretase inhibitor,DAPT,downregulated LSF expression in HepG2 cells.Additionally,a biological behavior assay showed that forced overexpression of LSF promoted HepG2 cell proliferation and invasion.CONCLUSION:LSF is a key mediator of the Notch signaling pathway,suggesting that it might be a novel therapeutic target for the treatment of HCC.展开更多
基金This project was supported by a grant from the National Natural Science Foundation of China (No.30471824).
文摘Summary: To investigate role of Notch1-3 in hyperoxia-induced lung injury in newborn rat exposed to 85% O 2, SD rat litters born on the 22th day were randomly divided into two groups: room air group and hyperoxia group. The animals were sacrificed 1, 4, 7, 10, 14 and 21 days after continued exposure to oxygen (n=40, oxygen>0.85) or room air (n=40). 6 rats each group were used to assess lung histological changes by HE staining and expression of Notch in lungs by immunohistochemistry. Total RNA was extracted by Trizol reagent from frozen lung tissues. Notch mRNA were measured by reverse transcription polymerase chain reaction (RT-PCR). Our results showed that 7, 14 and 21 days after O 2 exposure, hyperoxia group showed lung injury characterized by pulmonary edema, hemorrhage and lung development arrest. Positive staining for Notch1, Notch 2 in hyperoxia group was much lower than those in room air group at all time points (P<0.01, P<0.05), but compared with the controls, the hyperoxia group showed higher expression of Notch3 (P>0.05). Immunostained cells were typically airways epithelia, alveolar epithelial and inflammatory cells, and fibroblasts in hyperoxia group (P<0.01). Notch mRNA levels showed similar change as protein level (P< 0.01). It is concluded that the prolonged exposure to 85 % O 2 resulted in abnormal expression of Notch receptors, which might contribute to the pathogenesis of hyperoxia-induced lung injury in newborn rats. The decreased inhibition of Notch1 might be one of the protective reaction and major mechanisms for proliferation/differentiation of type Ⅱ alveolar epithelial cells. The up-regulation of Notch3 activity might result in the lung development arrest of the newborn rats.
文摘AIM:To investigate the role and clinicopathological significance of aberrant expression of Notch receptors and Delta-like ligand-4 (DLL4) in extrahepatic cholangiocarcinoma and gallbladder carcinoma.METHODS:One hundred and ten patients had surgically resected extrahepatic cholangiocarcinoma (CC) and gallbladder carcinoma specimens examined by immunohistochemistry of available paraffin blocks.Immunohistochemistry was performed using anti-Notch receptors 1-4 and anti-DLL4 antibodies.We scored the immunopositivity of Notch receptors and DLL4 expression by percentage of positive tumor cells with cytoplasmic expression and intensity of immunostaining.Coexistent nuclear localization was evaluated.Clinicopatho-logical parameters and survival data were compared with the expression of Notch receptors 1-4 and DLL4.RESULTS:Notch receptor proteins showed in the cytoplasm with or without nuclear expression in cancer cells,as well as showing weak cytoplasmic expression in non-neoplastic cells.By semiquantitative evaluation,positive immunostaining of Notch receptor 1 was detected in 96 cases (87.3%),Notch receptor 2 in 97 (88.2%),Notch receptor 3 in 97 (88.2%),Notch receptor 4 in 103 (93.6),and DLL4 in 84 (76.4%).In addition,coex- istent nuclear localization was noted [Notch receptor 1;18 cases (18.8%),Notch receptor 2;40 (41.2%),Notch receptor 3;32 (33.0%),Notch receptor 4;99 (96.1%),DLL4;48 (57.1%)].Notch receptor 1 expression was correlated with advanced tumor,node,metastasis (TNM) stage (P=0.043),Notch receptor 3 with advanced T stage (P=0.017),tendency to express in cases with nodal metastasis (P=0.065) and advanced TNM stage (P=0.052).DLL4 expression tended to be related to less histological differentiation (P=0.095).Coexistent nuclear localization of Notch receptor 3 was related to no nodal metastasis (P=0.027) and Notch receptor 4 with less histological differentiation (P=0.036),while DLL4 tended to be related inversely with T stage (P=0.053).Coexistent nuclear localization of DLL4 was related to poor survival (P=0.002).CONCLUSION:Aberrant expression of Notch receptors 1 and 3 play a role during cancer progression,and cytoplasmic nuclear coexistence of DLL4 expression correlates with poor survival in extrahepatic CC and gallbladder carcinoma.
基金Supported by The National Natural Science Foundation of China,No.30470780
文摘AIM:To investigate the relationship between late SV40 factor(LSF)and Notch signaling in the development and progress of hepatocellular carcinoma(HCC).METHODS:Liver cancer tissue specimens from 25 patients were analyzed for Notch-1 and LSF expression by immunohistochemistry.The correlation between expression and the biological effects of Notch-1 and LSF were analyzed using genetic and pharmacological strategies in HCC cell lines and human normal cell lines,including hepatic stellate cells(HSC)and human embryonic kidney epithelial cells(HEK).RESULTS:Immunohistochemistry showed that both Notch-1 and LSF were significantly upregulated in HCC samples(76%,19/25,P<0.0001 and 84%,21/25,P<0.0001,respectively)compared with non-cancer samples.Activation of Notch-1 by exogenous transfection of Notch1 intracellular domain increased LSF expression in HSC and HEK cells to levels similar to those seen in HepG2 cells.Furthermore,blocking Notch-1 activation with aγ-secretase inhibitor,DAPT,downregulated LSF expression in HepG2 cells.Additionally,a biological behavior assay showed that forced overexpression of LSF promoted HepG2 cell proliferation and invasion.CONCLUSION:LSF is a key mediator of the Notch signaling pathway,suggesting that it might be a novel therapeutic target for the treatment of HCC.
