蓖麻毒素对肝癌细胞有丝分裂原激活蛋白激酶的影响

为进一步探讨蓖麻毒素的毒作用机理 ,采用 Western印迹和免疫组化方法研究蓖麻毒素对人肝癌细胞内磷酸化状态和有丝分裂原激活蛋白激酶 (MAPK)的影响 .其结果表明 :蓖麻毒素能够影响细胞内的磷酸化状态 ,并能激活细胞内的有丝分裂原激活蛋白激酶 ,对 MAPK的激活有时间依赖性和剂量依赖性 . MAPK信号传导途径参与了蓖麻毒素对肝癌细胞的毒作用 .     

甲胎蛋白在体外对人肝癌细胞生长的影响

本文用MTT比色法观察了甲胎蛋白(AFP)在体外对人肝癌细胞生长的影响。结果表明,AFP能促进SMMC-7721人肝癌细胞的生长。当AFP与AFP抗体合用时,AFP抗体能减弱AFP对SMMC-7721细胞生长的促进作用;AFP抗体单用对此种细胞的生长亦有抑制作用。另一方面,在相同的实验条件下,AFP和AFP抗体对HL-60人白血病细胞的生长无明显影响;提示AFP的促生长作用具有一定的肿瘤细胞特异性,并非一种蛋白质对培养细胞的非特异性营养作用。此外,AFP亦能促进MCF-7人乳腺癌细胞的生长,AFP抗体对此种细胞的生长有抑制作用。由于MCF-7细胞存在功能性AFP受体,也能合成和分泌AFP。这就提示,人肝癌细胞中的AFP很可能与其受体特异性结合,产生促生长效应。确切机制尚待进一步阐明。     

Anti-proliferative effect of pterostilbene on rat hepatoma cells in culture

Pterostilbene, a methoxylated analogue of resveratrol, is a natural compound primarily found in blueberries and several types of grapes. However, little is known about the effect of pterostilbene on the proliferation of hepatoma cells and its modes of actions. This study was undertaken to characterize its ability to suppress the proliferation of hepatoma AH109A cells and the possible mechanism(s) involved. Pterostilbene showed a significant and dose-dependent effect on the anti-proliferative activity against AH109A cells. Pterostilbene exerted little or no effect on the proliferation of rat L6 myoblasts and rat skin fibroblasts. Pterostilbene-loaded rat sera could significantly inhibit the proliferation of AH109A cells, which suggests that pterostilbene could be absorbed through gastrointestinal tract and retain its anti-proliferative activity. Pterostilbene arrested the cell cycle of AH109A cells at G0/G1 phase and reduced the protein expression of cyclin-dependent kinase 4 and cyclin-dependent kinase 6 dose-dependently. We also found that pterostilbene could significantly increase the intracellular peroxide level of AH109A cells, which may be involved in its anti-proliferative activity.     

新型磁性纳米脂质复合物对肝癌细胞和肝细胞的作用研究

目的:研究新型磁性纳米脂质复合物对肝癌细胞和肝细胞的作用。方法:将肝癌细胞(Hep-G2)和肝细胞(L-02)根据加入的不同浓度新型纳米脂质复合物,各自分为空白对照组、不同浓度含铁脂质体组、空脂质体组,用MTT法观察各组细胞毒性,筛选出适合的浓度和时间;用普鲁士蓝染色、电镜检测观察各组细胞吞噬情况;用原子分光光度计观察各组细胞内铁含量;用细胞磁共振观察新型纳米脂质复合物体外显影效果。结果:新型磁性纳米脂质复合物含铁浓度在0.238μg/ml以上时,24小时有较强的细胞毒性,对肝癌细胞和肝细胞的抑制率均超过40%,故以下实验选择含铁浓度在0.238μg/ml以下;肝癌细胞和肝细胞与各浓度新型磁性纳米脂质复合物共同培养,24小时普鲁士蓝染色最高阳性率分别为5.5%和1.25%,24小时细胞内铁含量最高值分别为0.675pg/cell和0.460pg/cell;24小时电镜观察肝癌细胞和肝细胞空白对照组均未见颗粒样物质,各含铁脂质体组和空脂质体组均可见颗粒样物质;24小时肝癌细胞和肝细胞磁共振感兴趣区均未见明显信号表达。结论:新型磁性纳米脂质复合物含铁浓度在0.238μg/ml以下时,24小时细胞毒性较小;肝癌细胞对新型磁性纳米脂质复合物的吞噬作用稍高于肝细胞对其的吞噬;进入细胞内的新型磁性纳米脂质复合物含铁量低,体外显影效果不佳。     

5- 脱氧杂氮胞苷对人肝癌细胞HepG2 增殖及beclin1 表达的影响

目的:观察5-脱氧杂氮胞苷(5-aza-CdR)对HepG2细胞生长抑制及beclin1表达的影响,以探讨其抗肿瘤发生的潜在机制。方法:采用四甲基偶氮唑盐(MTT)法检测5-aza-CdR对HepG2细胞的生长抑制;用相差显微镜观察不同药物浓度下不同时间段的肝癌细胞形态学改变;采用RT-PCR法和Western blot法检测5-Aza-CdR对抑癌基因beclin1的mRNA和蛋白表达的影响。结果:5-aza-CdR可抑制HepG2细胞生长,呈剂量依赖性,并上调beclin1的mRNA和蛋白的表达。结果:显示102.4umol/L5-aza-C-dR作用72小时细胞增殖抑制率最高,可达(84.3±3.31)%,beclin1的mRNA和蛋白表达上调最明显,与对照组相比差异有统计学意义。结论:5-aza-CdR可抑制HepG2细胞增殖,其机制可能是通过恢复某些抑癌基因的表达,上调beclin1的mRNA和蛋白表达。     

樟芝液体发酵粉对肝癌H22的体内生长抑制作用(英文)

本文采用肝癌H22荷瘤小鼠的肿瘤模型,对樟芝液体发酵粉的体内抗肿瘤活性进行评价。结果表明,樟芝液体发酵粉(500或1000 mg/kg b.w.)能够体内显著抑制H22肿瘤的生长,抑制率分别为42.0%和46.4%。同时,与模型组相比,樟芝发酵粉能够延长荷瘤小鼠的生存周期,延长率为29.4%。组织病理学研究结果表明,模型组小鼠的肿瘤细胞生长旺盛,而樟芝发酵粉处理组的小鼠肿瘤细胞具有明显的皱缩和坏死症状。樟芝发酵产物具有较好的体内抗肿瘤活性。     

Comparative subcellular distribution of benzaldehyde and acetaldehyde dehydrogenase activities in two hepatoma cell lines and in normal hepatocytes.

The NAD- and NADP-dependent aldehyde dehydrogenase (ALDH) activities were evaluated in two rat hepatoma cell lines, namely the well-differentiated MH1C1 line and the less differentiated HTC line. Each activity was determined in parallel in isolated rat hepatocytes, for comparison. The aliphatic aldehyde acetaldehyde (ACA) and the aromatic aldehyde benzaldehyde (BA) were used as substrates. With the first substrate the ALDH activities found in the crude cytoplasmic extracts were lower in hepatoma cells than in normal hepatocytes, especially when measured with NADP as coenzyme (ACA/NADP). Otherwise, with benzaldehyde as substrate the NAD-dependent enzyme activity (BA/NAD) was increased about 9-fold in HTC cells over hepatocytes and decreased in MH1C1 cells, while the NADP-dependent (BA/NADP) activity was increased 38- and 2.5-fold in HTC and MH1C1 cell lines, respectively. Studies on the subcellular distribution of these enzyme activities showed that the activity measured with acetaldehyde and NAD (ACA/NAD) was almost equally distributed between the cytosol and the subcellular particles in the three cell populations, but the ACA/NADP activity was shifted towards the cytosolic compartment in hepatomas, especially in HTC cells. The BA/NAD and BA/NADP ALDH activities found in the organelles of hepatoma cells were markedly reduced in comparison with hepatocytes, in favour of the cytosol. The most striking difference between the normal and the transformed cells was the 94-fold increase over hepatocytes of the BA/NADP activity, found in the cytosolic fractions of HTC cells. MH1C1 cells showed a less pronounced (7.5-fold) enhancement of this tumour-associated specific activity.(ABSTRACT TRUNCATED AT 250 WORDS)     

RMP基因干扰对肝癌细胞周期的影响

目的:建立RMP(RPB5-Mediating Protein)基因干扰的稳定细胞株,研究RMP基因干扰对正常肝细胞及其肝癌细胞周期的影响.方法:构建RMP基因的短发卡RNA(short-hairpin RNA,shRNA)真核表达载体pGPU6-Neo-RMPi-484.通过脂质体转染的方法转染到SMMC-7721肝...     

Ultrasensitive detection of ferritin in human serum by Western blotting based on quantum dots-labeled avidin-biotin system

Various methods have been applied for serum ferritin detection, however, these methods still have some limitations. Over the last few years, quantum dots (QDs) have become very attractive for immunoassays because of their enormous potentials in ultrasensitive analysis. In this study, a Western blotting method combined with QDs‐labeled avidin–biotin system for detecting human serum ferritin was described. Meanwhile, the traditional diaminobenzidine (DAB)–horseradish peroxidase (HRP) method had been compared with the method. The linearity of this QDs‐based Western blotting method was from 0.27 to 1.1 ng, and the quantification limit was 0.27 ng, the sensitivity was up to pictogram values. Real serum samples such as hepatoma, thalassemia patient and normal individual sera were analyzed, the analysis results demonstrated that there was significant difference in the concentrations of ferritin between patients and normal individual serum. Furthermore, the recovery of ferritin from the serum samples of patients ranged from 98.15 to 119.67%, and the RSD (relative standard deviation) ranged from 8.73 to 11.61%, the repeatabilities were well within the acceptable range, which revealed that this method is a stable and reproducible method for detecting serum ferritin and have potential application prospect in clinical laboratory of serum ferritin detection.     

海藻色素糖蛋白对肝癌细胞Caspase-3和Bax蛋白表达的影响

目的：研究麒麟菜海藻色素糖蛋白（SPG）对肝癌细胞Caspase-3和Bax蛋白表达的影响。方法：将50只皮下接种H22肝癌细胞株的小鼠随机分为5组,每组10只。高、中、低剂量组分别每天经口灌胃给予100、50、10mg/kg的SPG,肿瘤对照组灌胃生理盐水,连续10d。环磷酰胺组隔天腹腔注射环磷酰胺20mg/kg.bw。取肝癌组织用MTT法测定各组肝癌细胞增殖活性,免疫组化法检测各组肝癌组织Caspase-3和Bax蛋白表达水平。结果：高剂量组Caspase-3和Bax蛋白表达率分别为40.20%和38.10%,而肿瘤对照组分别为5.00%和4.68%,差异均有显著性（P〈0.05）。高剂量SPG组和肿瘤对照组的肝癌细胞增殖活性分别为0.711±0.028和1.135±0.032,差别有显著性（P〈0.05）。结论：SPG可促进肝癌细胞Caspase-3和Bax蛋白表达,诱发肝癌细胞凋亡。