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1.
The prognosis of liver cancer was inferior among tumors. New medicine treatments are urgently needed. In this study, a novel exopolysaccharide EPS364 was purified from Vibrio alginolyticus 364, which was isolated from a deep-sea cold seep of the South China Sea. Further research showed that EPS364 consisted of mannose, glucosamine, gluconic acid, galactosamine and arabinose with a molar ratio of 5:9:3.4:0.5:0.8. The relative molecular weight of EPS364 was 14.8 kDa. Our results further revealed that EPS364 was a β-linked and phosphorylated polysaccharide. Notably, EPS364 exhibited a significant antitumor activity, with inducing apoptosis, dissipation of the mitochondrial membrane potential (MMP) and generation of reactive oxygen species (ROS) in Huh7.5 liver cancer cells. Proteomic and quantitative real-time PCR analyses indicated that EPS364 inhibited cancer cell growth and adhesion via targeting the FGF19-FGFR4 signaling pathway. These findings suggest that EPS364 is a promising antitumor agent for pharmacotherapy.  相似文献   
2.
对海南粗榧(Cephalotaxus hainanensis Li.)内生真菌F127发酵液化学组分进行研究。用多种色谱技术对F127代谢产物进行分离纯化,以LC-MS、ESI-MS和超导核磁共振分析鉴定化合物结构,最后采用MTT法测定化合物的抗肿瘤活性。从海南粗榧内生真菌F127的发酵液中分离得到5个单体化合物,分别鉴定为oblongolide T(1)、sorbicillin(2)、邻苯二甲酸二丁酯(3)、phomopsolide B(4)、6,8-二羟基-3-甲基-3,4-二氢异香豆素(5),且化合物1、4、5对肿瘤细胞K562、NB4、HL-60、Hep G-2和Lovo表现出不同抑制活性。化合物4对5株肿瘤细胞均表现出抑制活性,对K562、NB4、HL-60抑制效果显著,IC50值分别为3.35、0.014和0.16μg/m L,对Hep G-2和Lo Vo只有温和抑制作用;化合物1对K562、NB4、HL-60抑制作用良好,IC50值分别为51.82、54.25和29.31μg/m L;化合物5对NB4和Hep G-2则具有一定抑制活性;化合物2和3对测试细胞株未表现出抑制活性。5个化合物均是首次从海南粗榧内生真菌中分离得到,并首次报道了化合物1、4对K562、NB4、HL-60的优良细胞毒活性,为进一步研究海南粗榧内生真菌中的活性天然产物奠定了基础。  相似文献   
3.
以莰烯醛肟与卤代物为原料经亲核取代反应合成了9个未见报道的莰烯醛O-取代肟类化合物,分别为2-(3,3-二甲基双环[2.2.1]庚-2-亚基)乙醛O-苄基肟(2a)、2-(3,3-二甲基双环[2.2.1]庚-2-亚基)乙醛O-丁基肟(2b)、2-(3,3-二甲基双环[2.2.1]庚-2-亚基)乙醛O-(4-氯丁基)肟(2c)、2-(3,3-二甲基双环[2.2.1]庚-2-亚基)乙醛O-(3-溴苄基)肟(2d)、2-(3,3-二甲基双环[2.2.1]庚-2-亚基)乙醛O-(4-叔丁基苄基)肟(2e)、2-(3,3-二甲基双环[2.2.1]庚-2-亚基)乙醛O-(4-氯苄基)肟(2f)、2-(3,3-二甲基双环[2.2.1]庚-2-亚基)乙醛O-(4-氰基苄基)肟(2g)、2-(3,3-二甲基双环[2.2.1]庚-2-亚基)乙醛O-(2,6-二氯苄基)肟(2h)、2-(3,3-二甲基双环[2.2.1]庚-2-亚基)乙醛O-(邻氟苄基)肟(2i)。利用FT-IR、GC-MS、1H NMR以及13C NMR对产物结构进行了表征。以化合物2a为例,探索了不同工艺条件对产物得率的影响,在甲苯为溶剂,n(莰烯醛肟)∶n(氯化苄)∶n(四丁基溴化铵)为1.0∶1.8∶0.08,反应温度为60℃,反应时间为20 h的最佳工艺条件下,产物的得率为84.1%。通过体外抗肿瘤活性测试,探讨了化合物2a^2i对肝癌细胞HepG2和人乳腺癌细胞MCF7的抑制作用,结果表明:化合物2b对HepG2细胞的抑制作用较好,其半数抑制浓度(IC 50)值为36.3μmol/L;化合物2d、2h、2i对MCF7有一定的抑制作用,其中化合物2h对MCF7的抑制作用较好,其IC50值为19.2μmol/L。  相似文献   
4.
蛹虫草抗肿瘤和免疫活性部位的体外筛选   总被引:1,自引:0,他引:1  
为筛选蛹虫草(Cordyceps militaris)子实体的抗肿瘤和免疫活性部位,采用系统溶剂法,分别用氯仿、乙酸乙酯、95%的无水乙醇、沸水(100℃)、3%草酸铵和5%NaOH依次提取并计算提取物得率,且测定了沸水提取物、草酸铵提取物、NaOH提取物1和2的多糖含量.采用体外抗肿瘤模型测定了氯仿提取物、乙酸乙酯提取物和乙醇提取物对肿瘤细胞L1210和SW620的抑制活性;采用体外免疫增殖试验模型测定了沸水提取物、草酸铵提取物和NaOH提取物1和2的免疫活性.结果表明,乙酸乙酯提取物对肿瘤细胞L1210和SW620的抑制效果最好,当乙酸乙酯提取物浓度为200μg/mL时,抑制率分别为(85.2±2.5)%和(67.7±6.3)%;体外免疫活性测定结果表明,草酸铵提取物刺激小鼠脾淋巴细胞后的增殖活性最高,当浓度为500μg/mL时细胞增殖率为(312.0±7.2)%,与阳性对照PHA的细胞增殖率(329.3±3.0)%相当.  相似文献   
5.
依据文献资料,统计了广东省南岭国家级自然保护区内具有抗肿瘤活性的大型真菌种类。结果发现有55种大型真菌具有抗肿瘤作用,占全部已知种类的16.6%。有关标本保存在广东省微生物研究所真菌标本室(HMIGD)内。  相似文献   
6.
抗肿瘤DNA疫苗是一种调解免疫功能的基因治疗苗,它包括含有免疫刺激序列的质粒载体,肿瘤特异性抗原和肿瘤相关抗原表位。DC细胞将同时以抗原表位与MHC-I类分子形成复合物和与MHC-II分子形成复合物途径加工,提呈。活化CD4+和CD8+T细胞,同时产生抗肿瘤免疫和治疗作用。  相似文献   
7.
Diverse actinomycetes produce a family of structurally and biosynthetically related non-ribosomal peptide compounds which belong to the chromodepsipeptide family. These compounds act as bisintercalators into the DNA helix. They give rise to antitumor, antiparasitic, antibacterial and antiviral bioactivities. These compounds show a high degree of conserved modularity (chromophores, number and type of amino acids). This modularity and their high sequence similarities at the genetic level imply a common biosynthetic origin for these pathways. Here, we describe insights about rules governing this modular biosynthesis, taking advantage of the fact that nowadays five of these gene clusters have been made public (thiocoraline, triostin, SW-163 and echinomycin/quinomycin). This modularity has potential application for designing and producing novel genetic engineered derivatives, as well as for developing new chemical synthesis strategies. These would facilitate their clinical development.  相似文献   
8.
Sponges corresponding to the Jaspidae family have proved to be a prolific source of bioactive natural products. Among these, the bengamides and the bengazoles stand out by virtue of their unprecedented molecular architectures and impressive biological profiles, including antitumor, antibiotic and anthelmintic properties. As a consequence, intense research activity has been devoted to these compounds from both chemical and biological standpoints. This review describes in detail the research into these classes of natural products and the benefits they offer in chemistry and biology.  相似文献   
9.
茯苓发酵液的抑菌和抗肿瘤活性   总被引:1,自引:0,他引:1  
研究了茯苓(Wolfiporia cocos)发酵液的抑菌和体外抗肿瘤活性。结果表明:茯苓发酵液对金黄色葡萄球菌(Staphylococcus aureus)和白色念珠菌(Candida albicans)具有较好的抑制作用;茯苓发酵液对人宫颈癌细胞 Hela、小鼠黑色素瘤细胞B16和肝癌细胞 Hep-3B均具有较好的抑制效果,其作用48 h 的半抑制剂量为23.7、15.9和13.7μL。  相似文献   
10.
Dolastatin 10 (Dol-10), a leading marine pentapeptide isolated from the Indian Ocean mollusk Dolabella auricularia, contains three unique amino acid residues. Dol-10 can effectively induce apoptosis of lung cancer cells and other tumor cells at nanomolar concentration, and it has been developed into commercial drugs for treating some specific lymphomas, so it has received wide attention in recent years. In vitro experiments showed that Dol-10 and its derivatives were highly lethal to common tumor cells, such as L1210 leukemia cells (IC50 = 0.03 nM), small cell lung cancer NCI-H69 cells (IC50 = 0.059 nM), and human prostate cancer DU-145 cells (IC50 = 0.5 nM), etc. With the rise of antibody-drug conjugates (ADCs), milestone progress was made in clinical research based on Dol-10. A variety of ADCs constructed by combining MMAE or MMAF (Dol-10 derivatives) with a specific antibody not only ensured the antitumor activity of the drugs themself but also improved their tumor targeting and reduced the systemic toxicity. They are currently undergoing clinical trials or have been approved for marketing, such as Adcetris®, which had been approved for the treatment of anaplastic large T-cell systemic malignant lymphoma and Hodgkin lymphoma. Dol-10, as one of the most medically valuable natural compounds discovered up to now, has brought unprecedented hope for tumor treatment. It is particularly noteworthy that, by modifying the chemical structure of Dol-10 and combining with the application of ADCs technology, Dol-10 as a new drug candidate still has great potential for development. In this review, the biological activity and chemical work of Dol-10 in the advance of antitumor drugs in the last 35 years will be summarized, which will provide the support for pharmaceutical researchers interested in leading exploration of antitumor marine peptides.  相似文献   
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