INTRODUCTIONHepatocellular carcinoma (HCC) is one of the mostcommon human malignancies worldwide[1,2], and isclosely associated with infection of HBV and HCVand contamination of aflatoxin B1[3-6]. Althoughthe molecula...INTRODUCTIONHepatocellular carcinoma (HCC) is one of the mostcommon human malignancies worldwide[1,2], and isclosely associated with infection of HBV and HCVand contamination of aflatoxin B1[3-6]. Althoughthe molecular mechanisms of hepatocarcinogenesisremain poorly understood, an increasing number ofgenetic abnormalities have been recognized[7-10],for example, the p16 gene[11,12] the p53gene[13-18], the E-cadherin gene[19], and the c-mycgene[20].展开更多
目的:采用基因沉默和慢病毒转染技术,沉默人肝癌细胞HepG2中特异蛋白3(specificity protein 3,Sp3)的表达,观察沉默Sp3基因后的肝细胞的增殖能力变化.方法:采用Sp3-siRNA慢病毒转染人肝癌细胞HepG2,通过免疫印迹法和PCR技术检测Sp3的表...目的:采用基因沉默和慢病毒转染技术,沉默人肝癌细胞HepG2中特异蛋白3(specificity protein 3,Sp3)的表达,观察沉默Sp3基因后的肝细胞的增殖能力变化.方法:采用Sp3-siRNA慢病毒转染人肝癌细胞HepG2,通过免疫印迹法和PCR技术检测Sp3的表达以验证转染效果,通过MTT检测细胞生长曲线和流式细胞技术测定细胞周期.结果:Western blot实验表明,实验组的Sp3表达量明显少于空白组和阴性对照组(0.37±0.08 vs 0.83±0.17,0.66±0.13,F=8.442,均P<0.05).RT-PCR也得到相同的结果(0.47±0.05 vs 0.74±0.08,0.70±0.16,F=7.322,均P<0.05).MTT实验结果显示,与空白对照和阴性对照组相比,实验组细胞在48、72和96h时的增殖明显受到抑制(0.28±0.18 vs 0.34±0.19,0.35±0.07,F=3.888;0.57±0.11 vs 0.84±0.05,0.74±0.08,F=12.721;0.72±18.1 vs 0.98±0.05,0.93±0.9,F=6.342,均P<0.05).流式细胞术结果显示实验组细胞主要分布在G1期.结论:RNAi沉默Sp3基因导致人肝癌HepG2细胞体外增殖能力下降.展开更多
AIM To clarify whether endotoxin is of pathogenic importance for hepatocarcinogenesis, or the increased cancer risk results solely from the cirrhotic process. METHODS The rat model of hepatoma was treated by the in...AIM To clarify whether endotoxin is of pathogenic importance for hepatocarcinogenesis, or the increased cancer risk results solely from the cirrhotic process. METHODS The rat model of hepatoma was treated by the intake of 0 03% thioacetamide in drinking water for six months. During induction of hepatoma, rats were additionally treated with splenectomy and/or lipopolysaccharide administration. The liver nuclear DNA index and proliferation index were quantitatively analyzed by flow cytometry. Hepatic histology was examined with light and electron microscopes. Plasmic endotoxin concentration and γ glutamyl transpeptidase activity were measured, and hepatoma incidence was recorded. RESULTS Thioacetamide induced cirrhosis and hepatoma in Wistar rats with histology or regenerative nodule, fibrosis and neoplastic foci were quite similar to the pathogenic process of human cirrhosis leading to hepatoma. In comparison with TAA controls (DNA index: 1 15±0 21), exo endotoxin increased the DNA index by 7 8% (1 24±0 25, P <0 02) and hepatoma rate by 16 7. Splenectomy induced enteric endotoxemia increased the DNA index by 25% (1 44±0 15, P <0 01) and hepatoma rate by 33%. A summation of the effects of these two factors increased the DNA index by 36% ( P <0 01)and hepatoma incidence by 50%, moreover, the level of endotoxemia showed a close relation with DNA index ( r =0 96, P <0 01), as well as with the occurrence rate of hepatoma ( r =0 00, P <0 01). Histological findings further verified such alterations. CONCLUSION Lipopolysaccharide administration and/or splenectomy induced enterogenic endotoxemia may enhance rat hepatocarcinogenesis induced by oral intake of thioacetamide.展开更多
The present study was conducted to investigate whether mitochondrial pathway of apoptosis is involved in cyclooxygenase-2 (COX-2) inhibitor-induced growth inhibition of hepatoma cells. The growth rate and pattern of N...The present study was conducted to investigate whether mitochondrial pathway of apoptosis is involved in cyclooxygenase-2 (COX-2) inhibitor-induced growth inhibition of hepatoma cells. The growth rate and pattern of NS-398 (selective COX-2 inhibitor)-treated Hep3B hepatoma cells were analyzed by microscopic examination, DNA fragmentation gel analysis and flow cytometry followed by the cleavage of down-stream caspase 3 and the release of cytosolic fraction of cytochrome c assessed by Western blot analysis. NS-398 induced the growth inhibition of hepatoma cells depending on the concentration of this COX-2 inhibitor and time sequence. Ladder patterned-DNA fragmentation and cytometric redistribution to sub-G1 phase in cell cycle were revealed in NS-398-induced growth inhibition of hepatoma cells. Cytochrome c was translocated from mitochondria to cytosol in time-dependent manner following NS-398 treatment to hepatoma cells. COX-2 inhibitor induces the growth inhibition of hepatoma cells via caspase-dependent, mitochondria-mediated intrinsic apoptosis pathway. These results strongly suggest the possibility of therapeutic implication of COX-2 inhibitor in HCC.展开更多
基金Project supported partly by the National Natural Science Foundation of China, No. 39870344
文摘INTRODUCTIONHepatocellular carcinoma (HCC) is one of the mostcommon human malignancies worldwide[1,2], and isclosely associated with infection of HBV and HCVand contamination of aflatoxin B1[3-6]. Althoughthe molecular mechanisms of hepatocarcinogenesisremain poorly understood, an increasing number ofgenetic abnormalities have been recognized[7-10],for example, the p16 gene[11,12] the p53gene[13-18], the E-cadherin gene[19], and the c-mycgene[20].
文摘目的:采用基因沉默和慢病毒转染技术,沉默人肝癌细胞HepG2中特异蛋白3(specificity protein 3,Sp3)的表达,观察沉默Sp3基因后的肝细胞的增殖能力变化.方法:采用Sp3-siRNA慢病毒转染人肝癌细胞HepG2,通过免疫印迹法和PCR技术检测Sp3的表达以验证转染效果,通过MTT检测细胞生长曲线和流式细胞技术测定细胞周期.结果:Western blot实验表明,实验组的Sp3表达量明显少于空白组和阴性对照组(0.37±0.08 vs 0.83±0.17,0.66±0.13,F=8.442,均P<0.05).RT-PCR也得到相同的结果(0.47±0.05 vs 0.74±0.08,0.70±0.16,F=7.322,均P<0.05).MTT实验结果显示,与空白对照和阴性对照组相比,实验组细胞在48、72和96h时的增殖明显受到抑制(0.28±0.18 vs 0.34±0.19,0.35±0.07,F=3.888;0.57±0.11 vs 0.84±0.05,0.74±0.08,F=12.721;0.72±18.1 vs 0.98±0.05,0.93±0.9,F=6.342,均P<0.05).流式细胞术结果显示实验组细胞主要分布在G1期.结论:RNAi沉默Sp3基因导致人肝癌HepG2细胞体外增殖能力下降.
文摘AIM To clarify whether endotoxin is of pathogenic importance for hepatocarcinogenesis, or the increased cancer risk results solely from the cirrhotic process. METHODS The rat model of hepatoma was treated by the intake of 0 03% thioacetamide in drinking water for six months. During induction of hepatoma, rats were additionally treated with splenectomy and/or lipopolysaccharide administration. The liver nuclear DNA index and proliferation index were quantitatively analyzed by flow cytometry. Hepatic histology was examined with light and electron microscopes. Plasmic endotoxin concentration and γ glutamyl transpeptidase activity were measured, and hepatoma incidence was recorded. RESULTS Thioacetamide induced cirrhosis and hepatoma in Wistar rats with histology or regenerative nodule, fibrosis and neoplastic foci were quite similar to the pathogenic process of human cirrhosis leading to hepatoma. In comparison with TAA controls (DNA index: 1 15±0 21), exo endotoxin increased the DNA index by 7 8% (1 24±0 25, P <0 02) and hepatoma rate by 16 7. Splenectomy induced enteric endotoxemia increased the DNA index by 25% (1 44±0 15, P <0 01) and hepatoma rate by 33%. A summation of the effects of these two factors increased the DNA index by 36% ( P <0 01)and hepatoma incidence by 50%, moreover, the level of endotoxemia showed a close relation with DNA index ( r =0 96, P <0 01), as well as with the occurrence rate of hepatoma ( r =0 00, P <0 01). Histological findings further verified such alterations. CONCLUSION Lipopolysaccharide administration and/or splenectomy induced enterogenic endotoxemia may enhance rat hepatocarcinogenesis induced by oral intake of thioacetamide.
文摘The present study was conducted to investigate whether mitochondrial pathway of apoptosis is involved in cyclooxygenase-2 (COX-2) inhibitor-induced growth inhibition of hepatoma cells. The growth rate and pattern of NS-398 (selective COX-2 inhibitor)-treated Hep3B hepatoma cells were analyzed by microscopic examination, DNA fragmentation gel analysis and flow cytometry followed by the cleavage of down-stream caspase 3 and the release of cytosolic fraction of cytochrome c assessed by Western blot analysis. NS-398 induced the growth inhibition of hepatoma cells depending on the concentration of this COX-2 inhibitor and time sequence. Ladder patterned-DNA fragmentation and cytometric redistribution to sub-G1 phase in cell cycle were revealed in NS-398-induced growth inhibition of hepatoma cells. Cytochrome c was translocated from mitochondria to cytosol in time-dependent manner following NS-398 treatment to hepatoma cells. COX-2 inhibitor induces the growth inhibition of hepatoma cells via caspase-dependent, mitochondria-mediated intrinsic apoptosis pathway. These results strongly suggest the possibility of therapeutic implication of COX-2 inhibitor in HCC.
