Fanconi anemia （FA） is a rare recessive hereditary disease characterized clinically by congenital defects, progressive bone-marrow failure, and cancer predisposition. Cells from FA patients exhibit hypersensitivity ...Fanconi anemia （FA） is a rare recessive hereditary disease characterized clinically by congenital defects, progressive bone-marrow failure, and cancer predisposition. Cells from FA patients exhibit hypersensitivity to DNA cross-linking agents, such as mitomycin C （MMC）. To date, at least 12 FA genes have been found deleted or mutated in FA cells, and 10 FA gene products form a core complex involved in FA/BRCA2 DNA repair pathway-FA pathway. The ubiquitin E3 ligase FANCL, an important factor of FA core complex, co-functions with a new ubiquitin conjugating enzyme UBE2T to catalyze the monoubiquitination of FANCD2. FANCD2-Ub binds BRCA2 to form a new complex located in chromatin foci and then take part in DNA repair process. The deubiquitylating enzyme USP1 removes the mono-ubiquitin from FANCD2-Ub following completion of the repair process, then restores the blocked cell cycle to normal order by shutting off the FA pathway. In a word, the FANCD2 activity adjusted exquisitely by ubiquitination and/or deubiquitination in vivo may co-regulate the FA pathway involving in variant DNA repair pathway.展开更多
Objective: To investigate the expression and clinical significance of Fas andFasL in lung cancer. Methods: SP immunohistochemical technique was used to detect the expression ofFas and FasL in 46 cases of lung cancer a...Objective: To investigate the expression and clinical significance of Fas andFasL in lung cancer. Methods: SP immunohistochemical technique was used to detect the expression ofFas and FasL in 46 cases of lung cancer and 30 cases of adjacent non-neoplastic tissue. Results:Down-regulation, of Fas and up-regulation of FasL were found in lung carcinoma. The levels of Fasexpression in squamous cell carcinoma, adenocarcinoma and SCLC were significantly lower than that ofadjacent normal tissues (P<0. 01) , while the expression levels of FasL were the opposite (P< 0.05). Fas expression was associated with high histological grade and no metastasis (P<0. 05). FasLexpression was related to histological grade, late clinical stage and metastasis (P<0. 05). BothFas and FasL expression was not related to the histological type of lung cancer (P>0. 05). Thelevel of Fas expression was negatively related to that of FasL (P<0. 05). Conclusion:Down-regulation of Fas and up-regulation of FasL may work in coordination with the occurrence,development and metastasis of lung cancer. Fas or FasL can be used as one of markers in earlydiagnosis of lung cancer. Therefore, the combined assay may be helpful in predicting the grade ofmalignancy and the prognosis of patients with lung cancer.展开更多
OBJECTIVE: To evaluate the protective effects and mechanism of action of oxymatrine (OM) on the experimental fulminant hepatitis (FH) and early hepatocyte apoptosis in murine liver tissue. METHODS: Fulminant hepatitis...OBJECTIVE: To evaluate the protective effects and mechanism of action of oxymatrine (OM) on the experimental fulminant hepatitis (FH) and early hepatocyte apoptosis in murine liver tissue. METHODS: Fulminant hepatitis mice were induced by injecting lipopolysaccharide (LPS) intraperitoneally (ip) in galactosamine (GalN) sensitized mice.Two separate experiments were designed, including saline control group, fulminant hepatitis group and oxymatrine pretreated group (50 mg/kg, intraperitoneally, bid x 3 days). The levels of serum tumor necrosis factor alpha (TNFa) in mice from two experiments were determined at 5-hour and 7.5-hour after injecting galactosamine/lipopolysaccharide. Mouse liver samples at 5-hour time point were obtained for in situ end labeling (ISEL) staining and ultrastructural observation of apoptotic cells under transmission electron microscope (TEM). Liver samples at 7.5-hour time point were taken for hematoxylin-eosin (HE) staining and immunohistochemical staining of Fas and its ligand (FasL). RESULTS: As compared with the fulminant hepatitis group, the levels of serum tumor necrosis factor alpha in mice from the OM pretreated group at 5-hour and 7.5-hour time point were all significantly decreased (P展开更多
In the present study,we aimed to confirm whether NF-κB inhibitor pyrrolidine dithiocarbamate(PDTC)could induce apoptosis of human hepatic stellate cells(HSCs)LX-2 and explore the potential pharmacological mechanism u...In the present study,we aimed to confirm whether NF-κB inhibitor pyrrolidine dithiocarbamate(PDTC)could induce apoptosis of human hepatic stellate cells(HSCs)LX-2 and explore the potential pharmacological mechanism underlying these effects.In this study,LX-2 cells were cultured in vitro,and the experiment was divided into two groups,including the control and PDTC groups.The viability of LX-2 cells was measured by CCK8 assay after the cells were exposed to PDTC.The anti-apoptotic effect of PDTC was detected by AO/EB double assay staining kit.Additionally,the activities of NF-κB,Fas/FasL,apoptosis-related proteins,as well as the cellular localization of AIF,were determined by Western blotting analysis and immunofluorescence staining respectively.After PDTC treatment for 12 and 24 h,AO/EB dual staining showed typical apoptotic changes,such as cell volume reduction,cell shrinkage,nuclear fragmentation,and so on.PDTC at 60μmol/L significantly increased the proliferation inhibition rate and decreased the secretion of collagen I,collagen III,andα-SMA in LX-2 cells.The Western blotting analysis and RT-PCR showed no significant difference in the expression of AIF between the control group and PDTC group,and the expressions of Fas and FasL were not observed in all groups(P>0.05).Further results showed that PDTC could promote the displacement of AIF from mitochondria to the nucleus,activate the apoptotic signaling in the cell nucleus,and possibly participate in the apoptosis process of LX-2 cells.In conclusion,the pharmacological mechanism of PDTC against hepatic fibrosis might be to promote the displacement of AIF from mitochondria to the nucleus,then activate the apoptotic signaling in the cell nucleus,and finally induce the apoptosis of LX-2 cells.Meanwhile,these results also revealed that the Fas/FasL-mediated apoptosis pathway was not involved in the PDTC-induced apoptosis process of LX-2 cells.展开更多
基金This work was supported by the National Natural Sciences Foundation of China (No. 30470379).
文摘Fanconi anemia （FA） is a rare recessive hereditary disease characterized clinically by congenital defects, progressive bone-marrow failure, and cancer predisposition. Cells from FA patients exhibit hypersensitivity to DNA cross-linking agents, such as mitomycin C （MMC）. To date, at least 12 FA genes have been found deleted or mutated in FA cells, and 10 FA gene products form a core complex involved in FA/BRCA2 DNA repair pathway-FA pathway. The ubiquitin E3 ligase FANCL, an important factor of FA core complex, co-functions with a new ubiquitin conjugating enzyme UBE2T to catalyze the monoubiquitination of FANCD2. FANCD2-Ub binds BRCA2 to form a new complex located in chromatin foci and then take part in DNA repair process. The deubiquitylating enzyme USP1 removes the mono-ubiquitin from FANCD2-Ub following completion of the repair process, then restores the blocked cell cycle to normal order by shutting off the FA pathway. In a word, the FANCD2 activity adjusted exquisitely by ubiquitination and/or deubiquitination in vivo may co-regulate the FA pathway involving in variant DNA repair pathway.
文摘Objective: To investigate the expression and clinical significance of Fas andFasL in lung cancer. Methods: SP immunohistochemical technique was used to detect the expression ofFas and FasL in 46 cases of lung cancer and 30 cases of adjacent non-neoplastic tissue. Results:Down-regulation, of Fas and up-regulation of FasL were found in lung carcinoma. The levels of Fasexpression in squamous cell carcinoma, adenocarcinoma and SCLC were significantly lower than that ofadjacent normal tissues (P<0. 01) , while the expression levels of FasL were the opposite (P< 0.05). Fas expression was associated with high histological grade and no metastasis (P<0. 05). FasLexpression was related to histological grade, late clinical stage and metastasis (P<0. 05). BothFas and FasL expression was not related to the histological type of lung cancer (P>0. 05). Thelevel of Fas expression was negatively related to that of FasL (P<0. 05). Conclusion:Down-regulation of Fas and up-regulation of FasL may work in coordination with the occurrence,development and metastasis of lung cancer. Fas or FasL can be used as one of markers in earlydiagnosis of lung cancer. Therefore, the combined assay may be helpful in predicting the grade ofmalignancy and the prognosis of patients with lung cancer.
文摘OBJECTIVE: To evaluate the protective effects and mechanism of action of oxymatrine (OM) on the experimental fulminant hepatitis (FH) and early hepatocyte apoptosis in murine liver tissue. METHODS: Fulminant hepatitis mice were induced by injecting lipopolysaccharide (LPS) intraperitoneally (ip) in galactosamine (GalN) sensitized mice.Two separate experiments were designed, including saline control group, fulminant hepatitis group and oxymatrine pretreated group (50 mg/kg, intraperitoneally, bid x 3 days). The levels of serum tumor necrosis factor alpha (TNFa) in mice from two experiments were determined at 5-hour and 7.5-hour after injecting galactosamine/lipopolysaccharide. Mouse liver samples at 5-hour time point were obtained for in situ end labeling (ISEL) staining and ultrastructural observation of apoptotic cells under transmission electron microscope (TEM). Liver samples at 7.5-hour time point were taken for hematoxylin-eosin (HE) staining and immunohistochemical staining of Fas and its ligand (FasL). RESULTS: As compared with the fulminant hepatitis group, the levels of serum tumor necrosis factor alpha in mice from the OM pretreated group at 5-hour and 7.5-hour time point were all significantly decreased (P
基金supported by the Fujian Provincial Natural Science Foundation,China(Grant No.2019J01611)the Youth Project of Fujian Provincial Health Commission,Fujian Province,China(Grant No.2017-1-94).
文摘In the present study,we aimed to confirm whether NF-κB inhibitor pyrrolidine dithiocarbamate(PDTC)could induce apoptosis of human hepatic stellate cells(HSCs)LX-2 and explore the potential pharmacological mechanism underlying these effects.In this study,LX-2 cells were cultured in vitro,and the experiment was divided into two groups,including the control and PDTC groups.The viability of LX-2 cells was measured by CCK8 assay after the cells were exposed to PDTC.The anti-apoptotic effect of PDTC was detected by AO/EB double assay staining kit.Additionally,the activities of NF-κB,Fas/FasL,apoptosis-related proteins,as well as the cellular localization of AIF,were determined by Western blotting analysis and immunofluorescence staining respectively.After PDTC treatment for 12 and 24 h,AO/EB dual staining showed typical apoptotic changes,such as cell volume reduction,cell shrinkage,nuclear fragmentation,and so on.PDTC at 60μmol/L significantly increased the proliferation inhibition rate and decreased the secretion of collagen I,collagen III,andα-SMA in LX-2 cells.The Western blotting analysis and RT-PCR showed no significant difference in the expression of AIF between the control group and PDTC group,and the expressions of Fas and FasL were not observed in all groups(P>0.05).Further results showed that PDTC could promote the displacement of AIF from mitochondria to the nucleus,activate the apoptotic signaling in the cell nucleus,and possibly participate in the apoptosis process of LX-2 cells.In conclusion,the pharmacological mechanism of PDTC against hepatic fibrosis might be to promote the displacement of AIF from mitochondria to the nucleus,then activate the apoptotic signaling in the cell nucleus,and finally induce the apoptosis of LX-2 cells.Meanwhile,these results also revealed that the Fas/FasL-mediated apoptosis pathway was not involved in the PDTC-induced apoptosis process of LX-2 cells.
