低剂量X射线照射诱导HeLa细胞存活的

采用集落形成法观察了低剂量X射线照射HeLa细胞的存活率，结果表明，小于0．5Gy的X射线照射细胞的存活率高于对照，得到了HeLa细胞存活的“兴奋效应”，而且在0．25Gy附近这种效应更为明显；低剂量D1（0．05，0．75Gy)的预照射降低了随后攻击量D2对细胞的损伤程度，反映出低剂量照射可诱发细胞存活的“适应性反应”。     

Protective effects of Rad23 protein on ultraviolet damage to HeLa cells

Protein Rad23, a nucleotide excision repair factor, mainly involves in repairing the DNA damage from environment, such as UV light. The function of Rad23 protein involved in DNA damage repair from many environmental factors has been studied extensively, but it is not clear from ultraviolet irradiation. To further investigate the photo-protective function of Rad23 protein on HeLa cells damaged from UV light irradiation, firstly, HeLa cells were irradiated by UV light and incubated with the fusion protein of pCold-Rad23, then the cell viability and apoptosis rate were detected by MTT and Hoechst33342/Pl fluorescent staining, respectively. The results show that the recombinant Rad23 protein can protect the HeLa cells from UV irradiation, and inhibit the apoptosis of HeLa cell by UV irradiation.     

Lycium barbarum polysaccharide inhibits the proliferation of HeLa cells by inducing apoptosis

BACKGROUND: Lycium barbarum polysaccharide (LBP), isolated with boiling water from the famous Chinese medicinal herb Lycium barbarum fruits, is one of the most important functional constituents in Lycium barbarum. In this study the effects of LBP on cell proliferation, cell cycle and apoptosis in human cervical carcinoma cells (HeLa cells) were investigated. RESULTS: LBP could inhibit the proliferation of HeLa cells by changing cell cycle distribution and inducing apoptosis. In addition, the loss of mitochondrial transmembrane potential (Δψ_m) was observed by flow cytometry and the increase of intracellular Ca²⁺ concentration was detected by laser scanning confocal microscope in apoptotic cells. At the same time, the nitric oxide content, nitric oxide synthase and inducible nitric oxide synthase activities were also increased. CONCLUSION: The inhibitory effect of LBP on the proliferation of HeLa cells was caused by inducing apoptosis through the mitochondrial pathway. The results showed that LBP can be developed as a potential chemotherapeutic agent candidate against human cervical cancer. Copyright © 2012 Society of Chemical Industry     

Nanoparticles of Poly(Lactide-Co-Glycolide)-d-a-Tocopheryl Polyethylene Glycol 1000 Succinate Random Copolymer for Cancer Treatment

Cancer is the leading cause of death worldwide. Nanomaterials and nanotechnologies could provide potential solutions. In this research, a novel biodegradable poly(lactide-co-glycolide)-d-a-tocopheryl polyethylene glycol 1000 succinate (PLGA-TPGS) random copolymer was synthesized from lactide, glycolide and d-a-tocopheryl polyethylene glycol 1000 succinate (TPGS) by ring-opening polymerization using stannous octoate as catalyst. The obtained random copolymers were characterized by ¹H NMR, FTIR, GPC and TGA. The docetaxel-loaded nanoparticles made of PLGA-TPGS copolymer were prepared by a modified solvent extraction/evaporation method. The nanoparticles were then characterized by various state-of-the-art techniques. The results revealed that the size of PLGA-TPGS nanoparticles was around 250 nm. The docetaxel-loaded PLGA-TPGS nanoparticles could achieve much faster drug release in comparison with PLGA nanoparticles. In vitro cellular uptakes of such nanoparticles were investigated by CLSM, demonstrating the fluorescence PLGA-TPGS nanoparticles could be internalized by human cervix carcinoma cells (HeLa). The results also indicated that PLGA-TPGS-based nanoparticles were biocompatible, and the docetaxel-loaded PLGA-TPGS nanoparticles had significant cytotoxicity against Hela cells. The cytotoxicity against HeLa cells for PLGA-TPGS nanoparticles was in time- and concentration-dependent manner. In conclusion, PLGA-TPGS random copolymer could be acted as a novel and promising biocompatible polymeric matrix material applicable to nanoparticle-based drug delivery system for cancer chemotherapy.     

利用基于扫描相机的荧光寿命成像显微技术研究细胞周期

利用基于扫描相机的荧光寿命成像显微系统,以细胞周期为模型,研究转染绿色荧光蛋白的HeLa细胞的荧光寿命。结果表明,处于周期内不同进程的细胞的荧光寿命为2.50~3.00 ns。处于分裂期的细胞的荧光寿命在1 h内从2.86 ns下降到2.82 ns;在DNA合成前期的8 h内,荧光寿命从2.82 ns下降到2.78 ns。荧光寿命的差异反映了细胞周期中核浆内大分子浓度的变化,对了解细胞周期的分子机制有一定的意义。     

曲古菌素A处理HeLa细胞对其培养基的吸收光谱影响

本研究采集了不同剂量曲古菌素A（TSA）分别处理24h和48h下的人宫颈癌细胞株（HeLa cell）的培养基RPMI1640的紫外吸收光谱。结果显示：细胞培养基分别在233nm和275nm处有特征性的吸收峰。数据的进一步分析发现：不同剂量的TSA在处理细胞时间一致时,培养基的吸收光谱存在明显的差别。即：1）当TSA处理细胞24小时,伴随着用药剂量的增大,细胞培养基在233nm处的吸收值先降后升,275nm处的吸收值同样先降后升：2）当TSA处理细胞48小时,伴随着用药剂量的增大,细胞培养基在233nm处的吸收值越来越低,275nm处的吸收值却越来越高。这一结果反映了培养基中芳香族氨基酸和半胱氨酸残基的含量及比例变化,其变化规律与药物引起细胞的增殖改变有着密切的联系,并为动物实验和临床应用奠定了基础。     

三种多糖降解复合物体外抑制HeLa细胞的增殖作用

本文探讨了毛头鬼伞、龙须菜和坛紫菜三种多糖降解复合物体外抑制HeLa细胞增殖的协同效应及其作用机制。将毛头鬼伞、龙须菜和坛紫菜的多糖降解物复配成复合多糖降解物,采用MTT法检测复合多糖降解物对HeLa细胞增殖影响,DCFH-DA检测细胞内活性氧水平,JC-1检测线粒体膜电位变化情况。正交实验结果显示,当毛头鬼伞、龙须菜和坛紫菜三种多糖降解物以质量比为4:4:5组合时,对HeLa细胞的增殖抑制作用最强,在浓度为100μg/m L时,抑制率达75.72%,远高于三种单味多糖降解物单独使用时的最高抑制率56.09%;DCFH-DA、JC-1检测结果表明,复合多糖降解物可以显著提高细胞内活性氧水平,降低线粒体膜电位。以上结果均说明毛头鬼伞、龙须菜和坛紫菜三种多糖降解物复合后,对HeLa细胞的增殖抑制活性存在协同增效作用,该复合多糖降解物的作用机制可能与提高细胞内活性氧水平和降低线粒体膜电位有关。     

响应面试验优化脆江蓠多糖提取工艺及其对肿瘤细胞的抑制作用

目的：研究脆江蓠多糖（Gracilaria chouae polysaccharides,GLP）的提取方法及其对肿瘤细胞生长的影响。方法：响应面法优化GLP提取工艺条件;四甲基偶氮唑蓝（methyl thiazolyl tetrazolium,MTT）法检测GLP对体外培养的人宫颈癌（HeLa）、食道癌（EC-109）、肝癌（HepG-2）以及乳腺癌（MCF-7）细胞生长的影响。结果：GLP最佳提取条件为预热温度93.1 ℃、料液比1∶61.5（g/mL）、超声时间35 min,在此条件下GLP提取率为16.75%。GLP在质量浓度200～1 000 μg/mL范围内对实验细胞均有抑制作用,且呈剂量依赖关系。当GLP质量浓度为1 000 μg/mL时,其对HeLa、HepG-2、MCF-7和EC-109细胞的抑制率分别为49.11%、41.18%、34.98%和31.33%。对HeLa细胞形态学观察以及Annexin V-FITC/PI荧光染色检测发现,随着GLP给药剂量的增加,凋亡和坏死细胞不断增多。结论：GLP对体外培养的人HeLa、EC-109、HepG-2以及MCF-7等癌细胞增殖有抑制作用,并能诱导肿瘤细胞凋亡。     

白花蛇舌草对肿瘤细胞信号传导通路的抑制

研究了白花蛇舌草（Hedyotis diffusa）提取物对肿瘤细胞信号传导通路的影响。首先采取四甲基偶氮唑盐微量酶反应比色法（MTT）法测定各提取物对体外培养人宫颈癌细胞株HeLa增殖的抑制；进一步通过免疫印迹法分析了各提取物对EGF介导的Erk信号传导通路中Erk1／2蛋白磷酸化的影响。结果显示，煎煮及冷水提取物对HeLa细胞的增殖均有抑制，但两者无显著差别，而乙醇提取物显著抑制HeLa细胞增殖。对EGF介导Erk信号传导通路的影响显示。白花蛇舌苹提取物处理细胞90min后，EGF诱导的Erk1/2磷酸化水平显著降低，且表现浓度依赖性。抑制效果：乙醇提取物〉冷水提取物〉煎煮提取物。研究证明。中药白花蛇舌草含有信号传导通路抑制剂，可能在抗肿瘤过程中发挥重要作用。