红细胞血影介导7sRNA对大鼠肝癌细胞(CBRH-7919)DNA复制、转录和甲胎蛋白合成的影响

本文总结了用红细胞血影介导正常肝7sRNA进入肝癌细胞的定位及其对细胞DNA复制、转录和蛋白合成的影响。装载~(125)I-78RNA的血影与肝癌细胞融合后,放射自显影标本显示7sRNA在细胞内的分布,主要定位于细胞质,也有见于细胞核内。7sRNA进入细胞后对细胞的DNA复制、转录和蛋白合成有抑制作用。免疫荧光和免疫沉淀法检测肝癌细胞甲胎蛋白合成的结果表明,7sRNA导入晚G_1期同步细胞后继续培养4小时,甲胎蛋白合成减少。由于细胞DNA复制和转录被抑制,在一定程度上影响了甲胎蛋白基因的表达。     

Antioxidant Systems in Tumour Cells: The Levels of Antioxidant Enzymes,Ferritin, and Total Iron in a Human Hepatoma Cell Line

The human hepatoma cell line Hep 3B, which has the hepatitis B virus genome, shows over 80% decrease of copper/zinc superoxide dismutase activity, over 90% decrease of manganese superoxide dismutase activity, over 70% decrease of catalase activity, absence of glutathione peroxidase and glutathione S-transferase activities, over 270-fold increase of ferritin content and 25-fold increase of total iron compared to normal autopsy liver. These conditions of low antioxidant enzyme activities and iron overload are those which support the accumulation of oxygen free-radicals and DNA damage commonly considered to be carcinogenic mechanisms.     

Natural IgG antibody with anti-β-galactosyl specificity suppressed hepatoma cell invasion in culture

The effect of natural IgG antibody recognizing β-galactosyl epitope on hepatoma cell invasion was investigated. Anti-β-galactosyl antibody dose-dependently suppressed hepatoma invasion underneath primarily cultured mesothelial cells monolayer without affecting the proliferation, to the same extent as natural IgG antibody with anti-α-galactosyl specificity, which had already been reported to have an anti-metastatic activity. The inhibitory effect of anti-β-galactosyl antibody was completely canceled by adding lactose (galactose-β-1, 4-glucose) to the medium, indicating that this antibody recognized some antigens with β-galactosyl epitope. Hepatoma cells pretreated with this antibody for 48 h showed reduced invasive activity, while the pretreatment of mesothelial cells with the antibody did not affect hepatoma cells invasion. Anti-β-galactosyl antibody also suppressed hepatoma cells adhesion to mesothelial cells monolayer. These results suggest that natural antibody with anti-β-galactosyl specificity may recognize the β-galactosyl epitope in some adhesion-related molecules on hepatoma cells, thus suppressing adhesion and invasion to mesothelial cells monolayer. These results suggest possible therapeutic uses of this antibody in the treatment of metastatic tumors.     

A Glycomic Approach to Hepatic Tumors in N -acetylglucosaminyltransferase III (GnT-III) Transgenic Mice Induced by Diethylnitrosamine (DEN): Identification of Haptoglobin as a Target Molecule of GnT-III

A glycomic approach to the identification of target molecules in glycosyltransferase gene targeting mice is a promising strategy to understand the biological significance of glycosyltransferase genes in vivo. In order to understand the biological effects of N -acetylglucosaminyltransferase III (GnT-III) on tumor formation in the liver, diethylnitrosamine (DEN) induced tumor formation in the GnT-III transgenic mice was examined. Our findings show that the incidence of hepatic tumor could be dramatically suppressed. A glycomic approach using two-dimensional gel electrophoresis followed by lectin blot analysis and sequence analysis revealed that haptoglobin, a radical scavenger molecule in serum was heavily glycosylated in hepatic tumor-bearing GnT-III transgenic mice that had been treated with DEN. Immunoprecipitation followed by E 4 -PHA lectin blot analysis also confirmed that the bisecting GlcNAc, a product of GnT-III was added to haptoglobin molecules. Since the use of DEN is known to lead to the production of lipid peroxidation products which facilitate this reaction and haptoglobin is an acute phase reactant, acting as a radical scavenger against hemoglobin or iron stimulated lipid peroxidation, a relationship between the glycosylation of haptoglobin and the suppression of hepatoma development can not be ruled out. This paper is the first report that shows a relationship between the sugar chains of glycoproteins with radical scavenger activity and hepatocarcinogenesis.     

HA 纳米载体转hGM-CSF 基因的HepG2 疫苗的抗肿瘤活性研究

目的:评价HA纳米载体转hGM-CSF基因的HepG2疫苗的抗肿瘤活性。方法:SCID小鼠20只腹腔内注射健康志愿者外周血淋巴细胞(1×107/ml)1.0 ml,同时背部皮下接种人肝癌HepG2细胞(1×107ml)0.2 ml。当皮下移植瘤体积长至100 mm3时,随机分四组:Ⅰ组,60Co照射的转染GM-CSF基因的HepG2细胞组,Ⅱ组,60Co照射的HepG2细胞组,Ⅲ组,生理盐水组,Ⅳ组,接种前,每组5只。MTT法检测各组小鼠脾细胞CTL活性,ELISA法检测血清IL-4和IL-12的水平。结果:转染GM-CSF基因的HepG2疫苗组小鼠脾细胞CTL活性明显高于其余组(P<0.05);同时血清Th1类细胞因子IL-12的水平明显升高(P<0.05),而Th2类细胞因子IL-4的水平无统计学意义(P>0.05)。结论:HA纳米载体转hGM-CSF基因的HepG2疫苗可刺激机体产生特异性免疫反应。     

Specificity of Kirkman-Robbins hepatoma non-histone chromatin proteins: electrophoretic and immunological analyses

The specificity of Kirkman-Robbins hepatoma and hamster liver non-histone chromatin proteins has been studied by comparing polypeptide patterns in polyacrylamide gel electrophoresis and by their immunological activity in the complement fixation test. Non-histone proteins were separated from DNA with a polyethylene glycol-dextran mixture and fractionated by hydroxylapatite chromatography into three classes named NHCP1, NHCP2, and NHCP3. Electrophoretic analysis indicated that among the non-histone proteins of Kirkman-Robbins hepatoma and hamster liver differences mainly of a quantitative nature can be observed. However, the polypeptides with molecular weight 25 000, 31 000, 36 000, 73 000 in NHCP1; 20 000, 40 000 in NHCP2 and 20 000, 23 000, 32 000, 38 000, 44 000, 75 000, 80 000 in NHCP3 were found to be specific for hepatoma chromatin. Application of antibodies against NHCP1, NHCP2 and dehistonized chromatin of Kirkman-Robbins hepatoma revealed that the highest specificity of NHCP2 eluted from hydroxylapatite with 100 mM phosphate buffer at pH 6.8. The NHCP1 of hepatoma shares some common antigenic determinants with analogous proteins of liver. On the other hand non-histone proteins specific for hepatoma dehistonized chromatin can be localized in the NHCP3 and partially in the NHCP1 fractions.     

Oleanolic acid-NO donor-platinum(II) trihybrid molecules: Targeting cytotoxicity on hepatoma cells with combined action mode and good safety

By taking advantage of good affinity of oleanolic acid (OA) to the bile acid transporter, a series of hybrid compounds from oleanolic acid (OA) or OA-nitric oxide (NO) donor derivative coordinating to platinum(II) complexes were designed and synthesized. As expected, complexes 1c and 1d showed selective cytotoxicity to hepatoma carcinoma cells (e.g. HepG2, SMMC-7721, BEL-7402 cells) rather than other tumor cells. Interestingly, they had only a weak toxicity to normal hepatic cells (e.g. LO2 cells). Mechanism studies revealed that 1c could effectively bind to the ligand domain of the farnesoid X receptor and maintain the normal function of liver cells. Furthermore, the NO donor moiety could moderately release cytotoxic NO and finally enhance the cytotoxic effect, while the cytotoxicity of the corresponding complexes was decreased when the cells were pretreated with NO scavenger. Additionally, the agarose gel electrophoresis revealed that the Pt(II) part could also offer DNA binding activity, suggesting the complexes possess a combined action mode which may help to overcome the resistance of cisplatin. The flow cytometry studies found that 1c caused tumor apoptosis and blocked cell-cycle progression in the G2 phase.     

Large-scale sequencing analysis of the full-length cDNA library of human hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the human cancers clearly linked to viral infections. Although the major risk factors for HCC development have been elucidated, the hepatocellular carcinogenesis pathway resulting in malignant transformation of liver cells remains to be clarified. Recently, some results of microarray and comparative genomic hybridization analysis have been provided as comprehensive studies of genomic instability in HCC, including mutation, deletion and DNA copy losses. In this work, the full-length cDNA library has been constructed and sequenced, and the sequencing results have been further clustered and analyzed. The results show that 1,342 genes have been found, and about 300 of these genes may be important in e.g. cell proliferation, DNA repair and apoptosis. After further analysis of DNA sequences, the deletion genotypes of at least 24 genes have been found. However, the functional changes of these deletion mutants and their significance in hepatocellular carcinogenesis remain to be clarified. This research may be one of the best to obtain the candidate genes for hepatocellular carcinogenesis.     

人脐血CD34+细胞来源的树突状细胞疫苗在SCID小鼠体内的抗肿瘤免疫作用

目的观察脐血CD34 干细胞来源的树突状细胞(dendritic cells, DC)疫苗在严重联合免疫缺陷(severecombined immunity deficiency,SCID)小鼠体内对人肝癌细胞的免疫治疗和免疫保护作用.方法采用微磁珠分选系统(Mini MACS)从脐血单个核细胞中分离CD34 干细胞.重组人粒细胞-巨噬细胞集落刺激因子(recombined human granulocyte-macrophage colony-stimulating factor, rhGM-CSF)、重组人肿瘤坏死因子(recombined human tumor necrosis factor,TNF)-α诱导脐血CD34 细胞向DC分化,相差显微镜下观察DC分化过程中细胞的形态及数量变化.用人肝癌细胞BEL-7402裂解物冲击DC制备DC疫苗.在SCID小鼠体内观察DC疫苗致敏的淋巴细胞对人肝癌细胞的免疫治疗和免疫保护作用.结果脐血CD34 细胞在细胞因子诱导下,细胞形态由小变大、由圆形逐渐变为不规则形;细胞分裂扩增过程中,数量逐渐增多,形成细胞集落.经过细胞因子联合诱导2周的DC胞质突起丰富,具有典型的树枝状形态.在体内的抗肿瘤实验中,经DC疫苗致敏的人外周血淋巴细胞治疗荷瘤小鼠,肿瘤生长速度、瘤体积和重量明显小于未致敏淋巴细胞治疗组(P<0.05).与未致敏淋巴细胞免疫组和DC疫苗致敏的淋巴细胞治疗组比较,经DC疫苗致敏的淋巴细胞免疫SCID小鼠,肝癌细胞攻击后,肿瘤的发病率降低(P<0.05),发病潜伏期延长(P<0.01),肿瘤体积和重量减小(P<0.05).结论人脐血CD34 细胞来源的DC疫苗能在一定程度上抑制人肝癌细胞在小鼠体内的生长,抵抗肿瘤细胞的攻击,对机体具有相应的抗肿瘤免疫治疗和免疫保护作用.