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1.
DMSO对人胃腺癌MGC80—3细胞的诱导分化作用 总被引:5,自引:0,他引:5
用光镜、电镜和生化分析方法研究DMSO在体外对MGC80-3细胞的作用,不同浓度DMSO对MGC80-3细胞有不同的生长抑制作用。1.5%DMSO是本研究较适合的浓度。1.5%DMSO处理7天后细胞生长率、分裂指数、克隆形成率和Con-A凝集率分别下降35.15%、18%、90%和55.8%。处理后,癌细胞膜的碱性磷酸酶(不存在于正常人胃粘膜)比活性下降了90%,接种裸鼠致瘤率亦下降75%。处理后 相似文献
2.
5—羟色胺对肺动脉平滑肌细胞在缺氧条件下增殖的作用 总被引:2,自引:1,他引:1
本研究应用细胞培养、^3H-TdR掺入,核酸分子杂交、免疫组织化学染色技术,探讨无氧(0%O2+95%N2+5%CO2)和/或低氧(2.5 ̄3%O2+92%N2+5%CO2)对新生小牛肺动脉平滑肌细胞增殖和5-羟色胺转载体基因表达的影响。结果表明:无氧24h可刺激PASM的DNA合成,^3H-TdR的掺入增加(P〈0.05),加入5-羟色胺能非常显著地促进无氧PASM增殖(P〈0.001),而对常 相似文献
3.
盐生杜氏藻和青岛大扁藻的超低温保存 总被引:18,自引:0,他引:18
采用两步法冷冻技术超低浊保存盐生杜氏藻(Dunaliella salinu(Dunal)Teod.)和青岛大扁藻(Platymonas helgolandica Kylin var.tsigtaoensis)。当二甲基亚砚(DMSO)浓度分别为5%和20%,平衡时间均为min,预冻温度及保持时间分别为-40℃,60min和-30℃,30min;化冻后分别在0℃和到温下采用慢速稀释法去除DMSO时, 相似文献
4.
本实验以人卵巢癌细胞株(COC1)为模型,观察诱导分化剂二甲亚砜(DMSO)与维甲酸(RA)对该细胞生长增殖、DNA合成和转化生长因子β1(TGFβ1)在细胞内表达的影响。结果显示:DMSO与RA对人卵巢细胞COC1生长有明显的抑制作用,生长曲线表明作用5天后其生长抑制率分别为62.7%和42.1%;3H-胸腺嘧啶核苷(3H-TdR)掺入实验说明DMSO组与RA组的单位时间计数率(CPM)明显低于对照组(P<0.01)。用药3天后百分掺入抑制率分别为60.4%与37.9%,表明DMSO与RA抑制COC1细胞的DNA合成;免疫细胞化学反应表明,DMSO或RA处理5天后,对照组细胞TGFβ1表达为阳性,定位于胞浆,而处理组细胞TGFβ1呈阴性或弱阳性反应。以上结果提示DMSO和RA对人卵巢癌细胞有一定的诱导分化作用。 相似文献
5.
本研究着重探讨表皮生长因子(EGF)对大鼠肺动脉的收缩作用及对肺动脉平滑肌细胞分裂增殖的影响。浓度为1×10-9-1×10-7mol/L的EGF可引起大鼠肺动脉剂量依赖性收缩(r=0.968,P<0,001),其Emax为100.6mg,EC50为11.96nmol/L。在同时存在0.5%胎牛血清(FCS)时,EGF能促进平滑肌细胞的3H-TdR参入率,该作用与剂量呈正相关(r=0.823,P<0.05),其EC50为6.5×1O-12mol/L。1×10-9mol/L的EGF+0.5%FCS能产生与10%FCS相当的促细胞分裂增殖能力(在培养的第1,3,5,7天,二者促分裂增殖能力相差不明显,P均>0.05,第9天时,前者大于后者,P<0.05)。1×10-9mol/LEGF单独存在时对平滑肌细胞未显示出明显的致分裂活性。上述作用提示ECF在某些肺血管病变如缺氧性肺动脉高压中可能有一定意义。 相似文献
6.
氧化修饰HDL刺激培养人主动脉平滑肌细胞增殖 总被引:2,自引:0,他引:2
平滑肌细胞(smooth muscle cell,SMC)增殖在动脉粥样硬化(atherosclerosis,AS)形成中起着重要作用。氧化修饰HDL(oxidixed HDL,OX-HDL)可刺激^3H-TdR掺入培养人动脉SMC的DNA,促进SMC增殖。以四甲工偶氮唑盐9MTT)法直接观察OX-HDL对培养人动脉SMC增殖细胞数的影响。结果显示,天然HDL(native HDL N-HDL)对 相似文献
7.
SNP抑制5-HT诱导的胞内游离钙浓度升高和内钙释放 总被引:2,自引:0,他引:2
用Fura - 2/AM 荧光测量技术研究了5 - 羟色胺(5- HT) 诱导的大鼠尾动脉平滑肌细胞胞内钙升高和一氧化氮(NO) 的抑制效应。实验表明, 胞外0m mol/ L Ca2 + 时胞内静息[Ca2 + ] i 为20 .2±8 .6nmol/L(n = 8) 。10μmol/L 5- HT 可诱导出胞内钙库释放引起的瞬态[Ca2 +]i 升高,其峰值达245 .7 ±71.6nmol/ L(n = 6) 。10 - 7 mol/L 硝普钠(SNP) 可抑制5- HT 诱导的[Ca2 +]i 升高,其峰值浓度降为75.1±35 .9nmol/L(n = 5) 。当细胞浴液含2.5m mol/L Ca2 + 时,静息[Ca2 +]i为112 .8 ±10 .3nmol/ L(n = 5) , 这时10μmol/ L 5 - HT 可诱导[Ca2 + ] i 的峰值为252 .3 ±80 .6nmol/L(n = 4) ,以及其后平台浓度为143 .0 ±37 .6nmol/L(n = 4) ,略大于[Ca2 +]i 为112.8 ±10 .3nmol/L 的静息浓度,为外钙内流引起。10 - 7 mol/L SNP 也可抑制5- HT 诱导[Ca2 + ]i 平台相浓度。平台浓度由143 ±47 相似文献
8.
氧化修饰高密度脂蛋白对培养人动脉平滑肌细胞细胞周期蛋白D_1基因表达的影响 总被引:4,自引:0,他引:4
动脉平滑肌细胞(sm ooth m uscle cell,SMC)是动脉粥样硬化(atherosclerosis,AS)斑块中的主要细胞,它的增殖在AS形成过程中极其重要.利用体外培养的人主动脉SMC,观察了天然高密度脂蛋白(native high density lipoprotein,N-HDL)及氧化修饰HDL(oxidized HDL,OX-HDL)对培养人主动脉SMC cyclin D1(细胞周期蛋白D1)基因转录表达的影响.结果表明:(1)N-HDL对SMCcyclin D1基因表达无影响(P> 0.05);(2)OX-HDL使SMCcyclin D1基因表达显著增强(P<0.01),其表达量随时间(2、12、24 h)延长而增加.上述结果表明,OX-HDL的致AS作用可能与其刺激SMCcyclin D1基因表达增加有关. 相似文献
9.
对95例胃癌组织进行DAKO-M1(DAKO-CD15)表达的免疫组织化学研究。结果发现,DAKO-M1在胃癌中的阳性率(86.3%)显著高于癌旁粘膜和正常胃粘膜(P<0.05和0.005)。其定位分布有3种类型:即腺腔缘型(A型)、胞膜型(M型)和胞浆型(C型)。胃非肿瘤性粘膜组织仅为A型。胃癌3型兼有,高分化癌A型(18.2%)和M型(61.4%)均显著高于低分化癌(P值均<0.005);低分化癌和粘液癌C型(各占72.0%和53.8%)均显著高于高分化癌(20.5%),P<0.005和0.025。DAKO-M1C型和M型淋巴结转移率(分别为97.1%和69.2%)均显著高于A型(33.3%)者,P<0.005和0.05。结果提示,DAKO-M1是判断胃癌分化水平、恶性程度及预测淋巴结转移的一种有用标志物 相似文献
10.
为了探讨抗氧化剂对造血干细胞在低温条件下损伤的防护作用,将小鼠骨髓细胞置于4℃条件下保存,观察在保养液中加入不同浓度的Cu、Zn、SOD对细胞死伤的防护效果和马血清对细胞回收率的影响。结果表明,含20%的马血清保养液中加入SOD1.65U或0.165U/ml,保存3天,CFU-GM、CFU-E、BFU-E、CFU-Meg、CFU-Mix的产率分别为对照组(不加SOD)的6.2、2.6、2.9、4.0和5.1倍,明显提高了造血祖细胞的活存率,其中CFU-GM和CFU-Mix达到保存前水平。SOD的有效作用机理不是对造血祖细胞增殖调控作用,而是防护了细胞的死亡。这可能与其清除过氧自由基的抗氧化作用有密切关系。 相似文献
11.
研究小干扰RNA(small interfering RNA,siRNA)对乳腺癌MCF-7细胞株cyclin D1表达的抑制及对细胞增殖的影响。化学合成针对cyclin D1基因的siRNA,转染MCF-7细胞株;分别应用荧光定量PCR和免疫印迹测定cyclin D1 mRNA和蛋白的表达,CCK-8测定细胞的增殖活性,流式细胞仪检测细胞周期,软琼脂培养检测细胞克隆形成能力。在实验中,10、50、100 nmol/L siRNA-cyclin D1分别使MCF-7细胞cyclin D1 mRNA表达降低了57.85%、63.22%和68.02%,蛋白表达降低了51.13%、62.09%、77.68%。转染siRNA-cyclin D1后,细胞增殖受到抑制,细胞周期阻滞于G1期,软琼脂克隆形成率降低。结果提示siRNA可以有效抑制MCF-7细胞株中cyclin D1的表达,使细胞周期阻滞于G1期,从而抑制细胞增殖。 相似文献
12.
目的观察甲胎蛋白(AFP)在不同肿瘤细胞中的亚细胞定位及对肿瘤细胞生长的影响。方法运用免疫荧光的方法观察内源性AFP在HeI。a细胞、QGY-7703细胞、MCF-7细胞中的亚细胞定位。将构建的表达AFP的质粒pcDNA3-AFP及AFP腺病毒siRNA干涉载体Adv—AFPsiRNA作用于QGY-7703细胞,MCF-7细胞,运用M1Tr,集落形成实验检测细胞增殖状况。结果免疫荧光显示,内源性的AFP在HeLa细胞、QGY-7703细胞、MCF-7细胞均只在细胞质中表达。pcDNA3-AFP使QGY-7703的细胞活性增加了2l%(P〈0.05)及集落形成能力增加了32%(P〈0.01),MCF-7实验组比对照组细胞活性降低了30%(P〈0.01).克隆形成能力降低82%(P〈0.01)。Adv—AFPsiRNA使QGY-7703的细胞活性降低了22%(P〈0.05),平均克隆形成能力降低52%(P〈0.01),MCF-7细胞活性提高了24.5%(P〈0.05),克隆形成能力提高了89%(P〈O.01)。结论内源性的AFP只在细胞质中表达。AFP能促进QGY-7703细胞的增殖及克隆形成能力,而在MCF-7细胞中发挥相反的作用。腺病毒介导的内源性的AFP表达的下调能降低QGY-7703的增殖,却增加了MCF-7的细胞活性及克隆形成能力。 相似文献
13.
目的:研究Rab23分子对乳腺癌细胞生长增殖的作用,探讨这种作用是否与乳腺癌ER+/ER-依赖性相关。方法:选取ER+乳腺癌细胞系Bcap-37、MCF-7和ER-乳腺癌细胞系MDA-MB-231为研究对象,采用质粒转染提高细胞中Rab23基因的表达和RNA干涉技术减少其表达,运用克隆形成实验、BrdU掺入实验、MTT实验等技术检测Rab23分子对乳腺癌细胞生长、增殖的影响。结果:克隆形成实验提示,三种乳腺癌细胞系Rab23质粒转染组的集落形成数量明显少于对照组,而Gli1质粒转染组集落形成数量较对照组明显增加;BrdU掺入实验提示,Rab23转染组的三种乳腺癌细胞BrdU掺入率与对照组有明显减少(P<0.05),而Rab23干涉组的BrdU掺入率较对照组升高(P<0.05);MTT实验显示Rab23转染组A490值最低,其次为对照组,而Rab23干涉组A490值最高(P<0.05)。结论:Rab23分子对乳腺癌细胞生长增殖有抑制作用,这种抑制作用可能与乳腺癌ER+/ER-依赖性无相关性。 相似文献
14.
DAXX是Fas死亡结构域相关蛋白(Fas death-associated protein, DAXX),可与Fas死亡受体的死亡域结合.通过激活c-Jun NH2末端激酶通路,DAXX增强Fas介导的凋亡,同时也增强转录生长因子β依赖的凋亡.本研究通过免疫组化检测人正常卵巢组织和卵巢癌组织中DAXX蛋白表达,然后通过Tet-on诱导体系构建DAXX基因沉默的慢病毒,感染卵巢癌细胞后,加入嘌呤霉素筛选稳定表达的OV2008细胞,四环素诱导DAXX基因沉默,通过免疫印迹和定量PCR检测DAXX基因干扰效果,MTT检测细胞增殖,克隆形成实验检测克隆形成能力,免疫印迹和免疫荧光方法检测DNA损伤蛋白的变化,SA-β-gal检测细胞衰老.结果表明,在人正常卵巢组织中DAXX低表达,而在人卵巢癌组织中DAXX高表达,随着四环素浓度的增加DAXX的表达量降低,DAXX基因沉默抑制卵巢癌OV2008细胞的增殖和克隆形成. 免疫印迹结果显示,DAXX基因沉默可诱导DNA损伤相关蛋白p-H2AX和p-CHK2高表达.SA-β-gal检测结果表明,DAXX基因沉默可诱导OV2008细胞发生衰老,免疫印迹检测发现,p21和p27在 DAXX沉默的卵巢癌细胞中高表达.综上结果,DAXX沉默可以抑制卵巢癌细胞的增殖和克隆形成,同时也促进卵巢癌细胞发生DNA损伤和衰老.该研究为卵巢癌的基因治疗提供新的思路. 相似文献
15.
We investigated a new chemosensitivity test, MTT-hybrid assay, which was a hybrid of MTT colorimetric assay and double-layered soft agar colony assay, using human bone and soft tissue tumor cells. MTT formazan crystals produced by viable cells in the soft agar medium were solubilized by SDS at 60 degrees C. The absorbance (560 nm) is directly proportional to the cell number over a wide range. The absorbance increased in proportion to colonial growth of osteosarcoma cells, while it decreased in a human diploid cell strain in a few days. Drug sensitivity of tumor cells is supposed to be assessed without contaminating normal cells by MTT-hybrid assay in primary tumor samples. Good correlation of IC50 was observed between MTT-hybrid assay and colony assay. The MTT-hybrid assay shows potential value as a rapid predictive test for chemotherapeutic agents in an individual patient. 相似文献
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The ‘thymidine suicide’technique for indicating differences in the proliferation rate of early haemopoietic progenitor cells (spleen colony forming and agar colony forming cells) in C57BL mice has been evaluated. Special care was taken to use the same bone marrow cell suspension for the two progenitor cell assays. Both the in vivo and the in vitro techniques were employed. Following 3H-TdR in vivo, about 20% of both types of progenitor cell are killed in normal mice; however, after incubation in vitro with 3H-TdR, 35% of agar colony forming cells but only 4% of spleen colony forming cells are killed. Reasons for the difference between the in vivo and the in vitro results are discussed. With bone marrow from continuously irradiated animals, the thymidine suicide for both agar colony forming and spleen colony forming cells is in the range 42–50%, and there is no difference between in vivo and in vitro suicide. The in vivo results support the conclusion, based on the effect of proliferation dependent cytotoxic agents, that in C57BL mice agar colony forming and spleen colony forming cells are proliferating at the same rate in normal animals, and are speeded up to the same extent by continuous γ-irradiation. It is considered that in normal C57BL mice the in vitro method does not give a correct estimate of the proliferation rate of these progenitor cells. It would seem that the similarity in the proliferation rate of agar colony forming and spleen colony forming cells in C57BL mice is not true for other strains of mice: indeed using normal CBA and in vivo suicide, we have shown a significantly greater thymidine suicide for agar colony forming cells compared to spleen colony forming cells. 相似文献
18.
Fujimori K Kanaoka Y Sakaguchi Y Urade Y 《The Journal of biological chemistry》2000,275(51):40511-40516
The human hematopoietic prostaglandin D synthase (H-PGDS) gene is highly expressed in human megakaryoblastic cells, in which phorbol ester induces its expression. We characterized the promoter activity of the 5'-flanking region and the untranslated exon 1 (-1044 to +290) of the human H-PGDS gene in human megakaryoblastic Dami cells. Transient expression analysis using the luciferase reporter gene revealed that the 5'-flanking region and the untranslated exon 1 were sufficient for efficient expression of the H-PGDS gene in Dami cells, but not in monocytic U937 cells. Deletion and site-directed mutagenesis of the Oct-1 element in the 5'-flanking region decreased the promoter activity by approximately 30% compared with that of the entire region from -1044 to +290. An electrophoretic mobility shift assay demonstrated that Oct-1 specifically bound to the promoter region. Interestingly, even only untranslated exon 1 (+1 to +290) showed approximately 60% of the promoter activity of the entire region from -1044 to +290. Site-directed mutagenesis of the AP-2 element within the untranslated exon 1 abolished the basal promoter activity as well as its phorbol ester-mediated up-regulation. In AP-2-deficient HepG2 cells, the H-PGDS promoter activity was enhanced by coexpression with AP-2alpha. These findings indicate that the Oct-1 element in the 5'-flanking region acts as a positive cis-acting element and that the AP-2 element in the untranslated exon 1 is crucial for both basal and phorbol ester-mediated up-regulation of human H-PGDS gene expression in megakaryoblastic Dami cells. 相似文献
19.
The effect of mixed mutagen exposures on the rate and type of induced mutants was studied in the L5178Y/TK+/-----TK-/- mouse lymphoma cell mutagenicity assay. In this assay, exposure to ethyl methanesulfonate (EMS) results in more mutants that form large colonies than small colonies. Exposure to methyl methanesulfonate (MMS) results in more mutants that form small colonies than large colonies. Other reports in the literature suggest that large colony TK-/- mutants appear to result from small-scale, perhaps single-gene mutations, and that small-colony TK-/- mutants appear to be associated with chromosomal mutations. Treating cells for 4 h with simple, 2-component mixtures containing 6.45 micrograms/ml MMS and either 261, 392, 560 or 712 micrograms/ml EMS resulted in synergism of mutants at each mixture level. The frequencies of total mutants were synergized 12, 20, 35 and 72%, respectively, in mixed exposures with graded doses of EMS, above the sums of the mixture components. Small colony mutants were synergized to a greater extent than large colony mutants. The frequencies of small colony mutants in mixed exposures were increased 31, 54, 73 and 123%, respectively, while the frequencies of large colony mutants were increased -7, -6, 11 and 39%. Statistical analyses provide strong evidence of synergism (within the limits of the assay) for total and small-colony mutants at all doses of EMS tested, and for large-colony mutants above 400 micrograms/ml EMS. Similar magnitudes of synergism resulted when other constant levels of MMS (4.30 or 8.60 micrograms/ml) were mixed with the same graded doses of EMS. The degree of synergism was dependent on EMS concentration but not on MMS concentration. 相似文献
20.
siRNA对乳腺癌细胞Cyclin E表达和生长抑制作用 总被引:4,自引:0,他引:4
研究siRNA对乳腺癌MCF-7细胞株cyclin E表达的抑制及对细胞生长的影响。化学合成针对cyclin E基因的小干扰RNA(siRNA),转染MCF-7细胞株;分别应用荧光定量PCR和免疫印迹测定cyclin E mRNA和蛋白质的表达,CCK-8测定细胞的增殖活性,流式细胞仪检测细胞周期,软琼脂培养检测细胞克隆形成能力。10、50、100nmol/L siRNA-cyclin E分别使MCF-7细胞cyclin E基因表达降低了24.7%、62.5%和71.0%,蛋白质表达降低了40.8%、66.5%和71.3%。转染siRNA-cyclin E后,G1期细胞增多,S期减少,增殖受到抑制,软琼脂克隆形成率降低。结果提示,在MCF-7细胞株中,导入针对cyclin E的siRNA,可有效抑制cyclin E的表达,进而使细胞增殖减缓,逆转其恶性表型。 相似文献