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1.
通过急性毒性实验比较各制剂组的毒性,MTT法考查各制剂组对人体外癌细胞的生长抑制率,体内实验考查各制剂组对移植性肿瘤的抗肿瘤作用。结果表明,光合细菌(PSB)制剂组、光合细菌转化槲寄生(PSBT)制剂组无毒,PSBT降低了槲寄生的毒性;PSBT制剂组对人体外癌细胞BGC-803、A2780、KB和小鼠体内S180肉瘤、H22肝癌、Lewis肺癌均具有明显抑制作用,且抗肿瘤活性高于其他制剂组。  相似文献   

2.
采用聚丙烯酰胺凝胶电泳法对两种光合细菌的生物转化槲寄生培养液中菌体的蛋白质和几种同工酶进行研究,并以纯光合细菌培养液中菌体作对照。结果表明,光合细菌生物转化槲寄生过程中,两种光合细菌的蛋白质、酯酶同工酶和过氧化物酶同工酶均发生改变,某些蛋白质、酯酶和过氧化物酶的合成受到抑制,并有新的蛋白质、酯酶和过氧化物酶生成;超氧化物歧化酶的表达未明显改变。由此可见,槲寄生能诱导光合细菌合成新的酯酶和过氧化物酶,这些诱导酶可能参与了槲寄生的生物转化。为光合细菌生物转化槲寄生转化机理的研究及槲寄生在抗肿瘤领域的进一步应用奠定了基础。  相似文献   

3.
细菌DNA抗肿瘤免疫的实验研究   总被引:4,自引:1,他引:4  
应用纯化提取的3种细菌染色体DNA进行体内抗肿瘤免疫实验。结果表明,大肠埃希菌、铜绿假单胞菌和长双岐杆菌DNA由于含有大量的非甲基化的CpG二核苷酸为核心的序列(称为CpG motif),均能诱导NK细胞和单核细胞的激活,从而起到抗肿瘤免疫的作用。为微生物DNA制剂作为生物反应修饰剂(BRM)应用于抗肿瘤免疫提供了科学依据。  相似文献   

4.
肿瘤坏死因子相关凋亡诱导配体(TRAIL)是肿瘤坏死因子(TNF)超家族成员。因其具有选择性杀伤绝大多数肿瘤细胞而对人体正常细胞无明显细胞毒性的特性而被广泛研究,并已有相关制剂进入临床抗肿瘤研究。虽然TRAIL在体内外实验中均展现出良好的抗肿瘤效果,前期临床研究结果也表明了其相对安全性,但其临床抗肿瘤效果却不太理想。总结其临床效果差的主要原因,可能有体内稳定性差、肿瘤靶向性差、肿瘤获得性耐受等。对于TRAIL临床疗效差的问题,许多针对性的研究也相应开展,目前已有不少报道表明通过一些合理的优化方式有可能解决上述问题。我们从TRAIL的基因治疗、重组蛋白及死亡受体抗体治疗、TRAIL联合用药治疗及其他治疗方法等方面,简要综述TRAIL在抗肿瘤方面的应用及其应用中的优化。  相似文献   

5.
外泌体是由细胞分泌到胞外的囊泡状小体,体内多种细胞可以分泌外泌体,来源于树突状细胞(DC)和肿瘤细胞的外泌体表面表达MHC分子和抗原肽,体内外实验证明其具有抗肿瘤的作用,因此外泌体作为抗肿瘤疫苗被广泛研究。该文介绍外泌体的发现、蛋白质组成、体内抗肿瘤的机制,以及DC与肿瘤来源的外泌体的基础及临床研究。  相似文献   

6.
香菇C_(91-3)菌发酵液小鼠体内外抗肿瘤作用的研究   总被引:2,自引:1,他引:1  
香菇C_(91-3)菌是我们多年筛选出的一株经生物发酵后,其发酵液具有明显的抗肿瘤、抗细菌作用的真菌。研究结果表明:该发酵液具有明显体外抗肿瘤作用的活性物质。对MH_(134)、X5553、Ca761/L、YAC-1、H_(22)、K562抑瘤率为76.7~100%。在体内抗肿瘤实验中,采用H_(22)、S180腹水瘤的研究中,小鼠存活率分别为40%、45%。本文还对香菇C_(91-3)菌发酵液抗肿瘤的机理进行了探讨。  相似文献   

7.
人参皂苷IH901是一种天然二醇组人参皂苷肠道细菌最终代谢产物.目前研究表明,IH901具有抗肝癌活性,然而其作用机理尚不清楚.采用人肝癌细胞株SMMC-7721,HepG2,MHCC97-H来建立体内外的抗肿瘤模型,以探讨人参皂苷IH901的抗肝癌活性及其作用机理.结果发现,人参皂苷IH901能够通过细胞周期中亚二倍体峰的增加、线粒体跨膜电位(ΔΨm)崩溃、DNA梯形条带的形成和提高Caspase-9/Caspase-3的表达量、促进凋亡来抑制肝癌细胞的生长.通过抑制细胞的迁移和降低VEGF/bFGF的表达来抑制肝癌细胞的侵袭转移.裸鼠体内实验均表明了人参皂苷在体内外的抗肝癌活性,并且在分子、细胞、动物水平初步揭示了IH901抗肝癌生长及其侵袭转移的作用机理,为其作为抗肝癌药物的开发提供理论支持.  相似文献   

8.
采用阿霉素林外损伤大鼠心脏线粒体模型,研究天然抗氧化剂知母宁对阿霉素毒性及抗肿瘤活性的影响。结果表明:阿霉素体外引起大鼠心脏线粒体丙二醛(MDA)生成、ATP酶活性丧失及膜流动性降低等,知母宁对上述毒性损伤均有明显的保护作用;MTT法检测发现,知母宁对阿霉素的抗肿瘤活性无明显影响,这说明知母宁拮抗阿霉素引起的心脏毒性但不影响其抗肿瘤活性,这对临床应用知母宁以减轻阿霉素毒副的可能性提供了实验依据。  相似文献   

9.
树突状细胞是机体内最重要、功能最强的专职抗原递呈细胞,是抗肿瘤免疫的最好佐剂。将不同形式肿瘤抗原负载的DC制成疫苗,可以在体内诱导特异性杀伤性T细胞(CTL)的生成,激发人体有效的特异性抗肿瘤免疫功能。其中肿瘤抗原原因转当的DC疫苗具有很多独特的优点,可望作为一种新型肿瘤疫苗用于肿瘤的防治。本文主要就其作用特点、体内应用的可行性及抗肿瘤作用效果的实验研究进展等方面作一综述。  相似文献   

10.
光合细菌(PSB)对鲤鱼肠道菌群及肠消化功能的影响   总被引:13,自引:0,他引:13  
观察光合细菌对鲤鱼肠道中五种菌群(气单胞菌、大肠杆菌、乳酸杆菌、双歧杆菌、拟杆菌)及肠道中淀粉酶及蛋白酶活性的影响结果。实验结果表明:试验组肠道中光合细菌最高检出数为478±075(logn/克肠道内容物)且不为饲喂浓度的增加而增加。肠中大肠杆菌、拟杆菌的数量明显低于对照组(p>005),乳酸杆菌显著高于对照组(p<005),气单胞菌,双歧杆菌有增多趋势,但与对照组比较差异不显著(p<005),同时,光合细菌还可使肠道中的淀粉酶和蛋白酶活性分别比对照组提高268和294倍,差异显著,这可能是光合细菌添加剂一个重要的促生长作用因素。  相似文献   

11.
In this paper we report on three different hydrophilic copolymers based on alpha,beta-polyaspartylhydrazide (PAHy) bearing butyric groups in the side chain (C 4) (PAHy-C 4) or a combination of butyric groups and positive charged residues ((carboxypropyl)trimethylammonium chloride, CPTACl) (PAHy-C 4-CPTA) that were synthesized and used for the preparation of new supramolecular vesicular aggregates (SVAs) containing gemcitabine as an antitumor drug. Gemcitabine-loaded SVAs containing synthesized PAHy derivatives were characterized from the physicochemical and technological point of view and the in vitro toxicity and anticancer activity on two different human cancer cell lines, i.e., CaCo-2 (human colon carcinoma) and ARO (human anaplastic thyroid carcinoma) cells, were also evaluated. Moreover, considering that carrier-cell interaction is an important factor to achieve an improvement of anticancer drug activity, confocal laser scanning microscopy and flow cytometric experiments were carried out on the two different cancer cell lines.  相似文献   

12.
Eight new camphorato platinum complexes have been synthesized and evaluated for their in vitro cytotoxicity against HL-60 human leukemia, 3AO human ovarian carcinoma, BEL-7402 human hepatocarcinoma, and A549 human lung carcinoma cell lines. Most complexes showed good cytotoxic activity against the above-selected cell lines. Among the complexes, two compounds were assayed for their in vivo antitumor activity against LS-174T human colon carcinoma cells implanted in mice. One complex exhibited not only higher in vivo antitumor activity, but also less toxicity than oxaliplatin when it was administered intravenously at a dose of 6 mg/kg three times.  相似文献   

13.
CAPER is an estrogen receptor (ER) co-activator that was recently shown to be involved in human breast cancer pathogenesis. Indeed, we reported increased expression of CAPER in human breast cancer specimens. We demonstrated that CAPER was undetectable or expressed at relatively low levels in normal breast tissue and assumed a cytoplasmic distribution. In contrast, CAPER was expressed at higher levels in ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC) specimens, where it assumed a predominantly nuclear distribution. However, the functional role of CAPER in human breast cancer initiation and progression remained unknown. Here, we used a lentiviral-mediated gene silencing approach to reduce the expression of CAPER in the ER-positive human breast cancer cell line MCF-7. The proliferation and tumorigenicity of MCF-7 cells stably expressing control or human CAPER shRNAs was then determined via both in vitro and in vivo experiments. Knockdown of CAPER expression significantly reduced the proliferation of MCF-7 cells in vitro. Importantly, nude mice injected with MCF-7 cells harboring CAPER shRNAs developed smaller tumors than mice injected with MCF-7 cells harboring control shRNAs. Mechanistically, tumors derived from mice injected with MCF-7 cells harboring CAPER shRNAs displayed reduced expression of the cell cycle regulators PCNA, MCM7, and cyclin D1, and the protein synthesis marker 4EBP1. In conclusion, knockdown of CAPER expression markedly reduced human breast cancer cell proliferation in both in vitro and in vivo settings. Mechanistically, knockdown of CAPER abrogated the activity of proliferative and protein synthesis pathways.  相似文献   

14.
目的建立人宫颈癌鸡胚模型,探讨其形态学及生物学特性。方法将Hela细胞接种于鸡胚绒毛尿囊膜,观察影响宫颈癌鸡胚移植瘤成活可能的因素、移植瘤生长特性、形态、生物学特性。结果成功建立了人宫颈癌鸡胚移植瘤模型。移植后瘤易于生长,具有较强的血管诱导作用。光镜下显示移植后瘤具有与人宫颈癌相似的组织结构。结论该模型容易建立,能动态观察宫颈癌诱导血管生成的全过程,可用于宫颈癌的实验研究。  相似文献   

15.
The present study was designed to determine the effects of artemisinin (ARS) and its derivatives on human ovarian cancer cells, to evaluate their potential as novel chemotherapeutic agents used alone or in combination with a conventional cancer chemotherapeutic agent, and to investigate their underlying mechanisms of action. Human ovarian cancer cells (A2780 and OVCAR-3), and immortalized non-tumourigenic human ovarian surface epithelial cells (IOSE144), were exposed to four ARS compounds for cytotoxicity testing. The in vitro and in vivo antitumour effects and possible underlying mechanisms of action of dihydroartemisinin (DHA), the most effective compound, were further determined in ovarian cancer cells. ARS compounds exerted potent cytotoxicity to human ovarian carcinoma cells, with minimal effects on non-tumourigenic ovarian surface epithelial (OSE) cells. DHA inhibited ovarian cancer cell growth when administered alone or in combination with carboplatin, presumably through the death receptor- and, mitochondrion-mediated caspase-dependent apoptotic pathway. These effects were also observed in in vivo ovarian A2780 and OVCAR-3 xenograft tumour models. In conclusion, ARS derivatives, particularly DHA, exhibit significant anticancer activity against ovarian cancer cells in vitro and in vivo , with minimal toxicity to non-tumourigenic human OSE cells, indicating that they may be promising therapeutic agents for ovarian cancer, either used alone or in combination with conventional chemotherapy.  相似文献   

16.
Summary The severe combined immunodeficient (SCID) mouse, lacking functional T and B lymphocytes, has been considered by many groups to be a prime candidate for the reconstitution of a human immune system in a laboratory animal. In addition, this immuno-deficient animal would appear to have excellent potential as a host for transplanted human cancers, thus providing an exceptional opportunity for the study of interactions between the human immune system and human cancer in a laboratory animal. However, because this animal model is very recent, few studies have been reported documenting the capability of these mice to accept human cancers, and whether or not the residual immune cells in these mice (e.g. natural killer, NK, cells; macrophages) possess antitumor activities toward human cancers. Thus, the purpose of this study was (a) to determine whether or not a human breast carcinoma cell line (MCF-7) can be successfully transplanted to SCID mice, (b) to determine whether or not chronic treatment of SCID mice with a potent lymphokine (recombinant interleukin-2, rIL-2) could alter MCF-7 carcinoma growth, and (c) to assess whether or not rIL-2-activated NK cells (LAK cells) are important modulators of growth of MCF-7 cells in SCID mice. To fulfill these objectives, female SCID mice were implanted s.c. with MCF-7 cells (5 × 106 cells/mouse) at 6 weeks of age. Six weeks later, some of the mice were injected i.p. twice weekly with rIL-2 (1 × 104 U mouse–1 injection–1). Results clearly show that MCF-7 cells can grow progressively in SCID mice; 100% of the SCID mice implanted with MCF-7 cells developed palpable measurable tumors within 5–6 weeks after tumor cell inoculation. In addition, MCF-7 tumor growth was significantly (P <0.01) suppressed by rIL-2 treatment. rIL-2 treatment was non-toxic and no effect of treatment on body weight gains was observed. For non-tumor-bearing SCID mice, splenocytes treated in vitro with rIL-2 (lymphokine-activated killer, LAK, cells) or splenocytes derived from rIL-2-treated SCID mice (LAK cells) had significant (P <0.01) cytolytic activity toward MCF-7 carcinoma cells in vitro. In contrast, splenocytes (LAK cells) derived from tumor(MCF-7)-bearing rIL-2-treated SCID mice lacked cytolytic activities toward MCF-7 cells in vitro. No significant concentration of LAK cells in MCF-7 human breast carcinomas was observed nor did rIL-2 treatment significantly alter growth of MCF-7 cells in vitro. Thus, while rIL-2 treatment significantly suppressed growth of MCF-7 breast carcinomas in SCID mice, the mechanism of this growth suppression, albeit clearly not involving T and B lymphocytes, does not appear to be mediated via a direct cytolytic activity of LAK cells toward the carcinoma cells. However, rIL-2-activated SCID mouse splenocytes (LAK cells) do possess the capability of significant cytolytic activity toward MCF-7 human breast carcinoma cells. Thus, treatment of SCID mice with a potent lymphokine (rIL-2) induces a significant antitumor host response, a response that does not involve T and B lymphocytes and appears not to involve NK/LAK cells. This host response must be considered in future studies designed to investigate the interactions of reconstituted human immune systems and human cancers within this highly promising immuno deficient experimental animal model.  相似文献   

17.
目的采用裸鼠皮下移植瘤模型,通过不同给药途径对胡桃醌抗肿瘤活性和毒性进行评价。方法建立人肝癌BEL-7402细胞裸鼠皮下移植瘤模型,通过腹腔注射和局部注射两个给药途径观察胡桃醌抑制肿瘤生长的效果。结果①以600、300和150μg/kg胡桃醌腹腔注射于人肝癌BEL-7402细胞裸鼠皮下移植瘤模型,发现该剂量胡桃醌对肿瘤生长没有明显的影响;NK细胞活性检测发现,600、300μg/kg胡桃醌对裸鼠免疫功能有影响(P均<0.01),150μg/kg胡桃醌则没有影响(P>0.05);与阳性对照组(5-Fu)相比,600μg/kg胡桃醌组NK细胞活性差异无显著性(P>0.05),300和150μg/kg胡桃醌组NK细胞活性差异有显著性(P<0.05,P<0.01),结果提示胡桃醌对小鼠免疫系统有一定的损伤作用。②以4.5、3和1.5 mg/kg胡桃醌腹腔注射于人肝癌BEL-7402细胞裸鼠皮下移植瘤模型,抑瘤率分别为为78.24%、66.57%、48.94%;4.5、3 mg/kg胡桃醌的抑瘤作用可与阳性对照组比拟(P均>0.05)。但4.5 mg/kg胡桃醌组裸鼠出现明显的皮下脂肪减少、消瘦,并有死亡现象。③以pH 7.4和pH 4.0的600、300和150μg/kg胡桃醌人肝癌BEL-7402细胞裸鼠皮下移植瘤模型局部给药,结果发现不同pH(pH 7.4或4.0)600、300μg/kg的胡桃醌局部注射抑瘤作用与阳性对照组(5-Fu)组差异无显著性(P>0.05),而不同pH的150μg/kg胡桃醌抑瘤作用不明显。同一浓度不同pH药物的抑瘤作用差异无显著性(P均>0.05),但pH 4.0的胡桃醌组肿瘤细胞肝转移较少。结论胡桃醌不同给药途径均可抑制人肝癌BEL-7402细胞裸鼠皮下移植瘤的生长,但有一定的毒副作用,药物安全范围较小。  相似文献   

18.
Magnolol, a hydroxylated biphenyl compound isolated from the Chinese herb Hou p'u of Magnolia officinalis, has been reported to have anti-cancer activity. In the present study, magnolol at very low concentrations of 3-10 microM inhibited DNA synthesis and decreased cell number in cultured human cancer cells (COLO-205 and Hep-G2) in a dose-dependent manner, but not in human untransformed cells such as keratinocytes, fibroblasts, and human umbilical vein endothelial cells (HUVEC). Magnolol was not cytotoxic at these concentrations and this indicates that it may have an inhibitory effect on cell proliferation in the subcultured cancer cell lines. [(3)H] thymidine incorporation and flow cytometry analyses revealed that magnolol treatment decreased DNA synthesis and arrested the cells at the G0/G1 phase of the cell cycle. Moreover, the magnolol-induced cell cycle arrest occurred when the cyclin-CDK system was inhibited, just as p21 protein expression was augmented. When magnolol concentration was increased to 100 microM, apoptosis was observed in COLO-205 and Hep-G2 cells, but not in cultured human fibroblasts and HUVEC. COLO-205 cells implanted subcutaneously in nude mice formed solid tumors; subsequent daily i.p.-injections of magnolol led to profound regression of these tumors of up to 85%. In these tumors, an increase in the expression of p21 protein level and the occurrence of apoptosis were observed. These findings demonstrate for the first time that magnolol can inhibit the proliferation of tumor cells in vitro and in vivo.  相似文献   

19.
目的:建立-种基于分泌型萤光素酶的实时定量检测实验动物体内肿瘤大小的方法。方法:以分泌型Gaussia萤光素酶(Gluc)为报告基因,以嘌呤霉素为筛选基因,将两者用T2A元件连接后克隆到慢病毒载体,包装慢病毒后感染乳腺癌MCF-7细胞,经嘌呤霉素筛选得到稳定转染细胞MCF-7-Gluc,并检测细胞上清中Gluc活性随时问和细胞数目的变化;将MCF-7-Gluc扩大培养后经皮下注射到雌性BALB/c裸鼠前肢腋下,待肿瘤形成后,检测外周血液中Gluc活性与肿瘤体积的相关性。结果:体外实验显示稳定转染细胞MCF-7-Gluc分泌到细胞上清的Gluc活性与时间和细胞数量在-定范围内均呈现良好的线性关系,体内实验显示裸鼠血液中的Gluc活性与肿瘤体积呈正相关。结论:Gluc技术可作为-种灵活、方便、实时定量检测活体动物体内肿瘤大小的有效工具。  相似文献   

20.
The cytotoxic activity of L-asparaginases from Yersinia pseudotuberculosis and from Erwinia carotovora were investigated in vitro using human T-lymphoblastic leukemia (Jurkat and Molt-4) and also solid tumor cell lines MCF-7 (human breast adenocarcinoma), LnCap (human prostate carcinoma), NGUK1 (rat Gasser node neurinoma). E.coli L-asparaginase produced by Medak (Germany) was used as a reference preparation. The data obtained indicate that Y. pseudotuberculosis L-asparaginase significantly inhibits growth of leukemic and solid tumor cells. Its antitumor activity is comparable to that of the reference preparation of L-asparaginase (Medak). These results suggest that the recombinant L-asparaginase can be used for the development of new preparations for the therapy of different types of tumors.  相似文献   

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