苦参碱对肿瘤细胞获得性多药耐药的逆转作用

目的:观察苦参碱对模拟临床化疗CFP方案诱导的小鼠S180肿瘤细胞获得性多药耐药的逆转作用,明确其对多药耐药逆转的作用及其作用机制.以指导临床应用苦参碱逆转肿瘤患者多药耐药,提高化疗疗效.方法:模拟临床CFP方案,分别给予小鼠顺铂3 mg·kg-1,ip,每周1次;环磷酰胺和5-FU各3 mg·kg-1,ig,qd,连续4周,流式细胞术荧光检测观察其对MDR细胞膜糖粘蛋白P170、细胞凋亡及其相关因子Fas、Trail和细胞黏附因子CS54的影响.结果:苦参碱抑制P170表达、增加对细胞凋亡因子Fas、Trail表达率,促进耐药S180细胞的凋亡,降低细胞黏附因子CD54的表达.结论:说明苦参碱逆转肿瘤获得性多药耐药与对肿瘤多种相关生物分子因子的调节有关.临床可以根据肿瘤多药耐药的性质,通过调节多药耐药相关因子逆转肿瘤化疗耐药性,提高临床化疗疗效.     

温下方逆转A549/DDP细胞的多药耐药及对膜表面蛋白表达的影响

目的运用血清药理学方法,体外研究温下方对A549/DDP细胞多药耐药的逆转作用及机制。方法正常血清及不同浓度的温下方含药血清作用于A549/DDP细胞,四甲基偶氮唑蓝(MTT)法检测温下方含药血清对A549/DDP细胞的逆转作用;运用免疫荧光技术,激光共聚焦显微镜及流式细胞仪检测肺耐药相关蛋白(LRP)、多药耐药相关蛋白(MRP)和P-糖蛋白(P-gp)的表达。结果温下方含药血清能明显逆转A549/DDP细胞的多药耐药,增敏倍数为2～2.5倍。并可明显降低P-gp、LRP、MRP蛋白表达。结论温下方通过降低P-gp、LRP、MRP的表达以增强A549/DDP对化疗药的敏感性,逆转肺腺癌细胞的多药耐药。     

RNAi逆转淋巴瘤LRP和P-gp介导的多药耐药研究

目的 应用RNA干扰(RNA interference,RNAi)技术逆转淋巴瘤中P-糖蛋白(P-glycoprotein,P-gp)和肺耐药蛋白(lung resistance protein,LRP)介导的多药耐药(multidrug resistance,MDR).方法 采用细胞毒性试验、荧光定量PCR、Western blot等方法观测双靶向干扰载体对P-gp和LRP介导的MDR的逆转作用.结果 采用干扰质粒转染耐药淋巴瘤细胞后,该细胞的耐药指数降低,外排米托蒽醌的能力降低,细胞中P-gp、LRP的mRNA和蛋白表达水平也显著降低,且差异均有统计学意义(P＜0.05).结论 构建的双靶向干扰载体能在体外逆转淋巴瘤细胞中P-gp和LRP介导的非典型性多药耐药.     

黄芩苷逆转人肝癌细胞耐药株Bel-7402/ADM多药耐药性的相关机制研究

目的 考察黄芩苷对人肝癌耐药细胞Bel-7402/ADM 多药耐药性的逆转机制.方法 MTT法考察Baicalin对人肝癌多药耐药细胞的逆转作用.结果 Baicalin逆转Bel-7402/ADM多药耐药性的机制可能与抑制MDR1部分基因产物P-gp、MRP、GSH/GST的表达和诱导细胞凋亡有关.结论 Baicalin可能通过抑制MDR1部分基因产物P-gp、MRP、GSH/GST的表达和诱导细胞凋亡逆转Bel-7402/ADM的多药耐药性.     

骨肉瘤组织中P-qp及LRP的表达与临床病理特点关系的研究

目的 研究P-糖蛋白(P-gp)及肺耐药相关蛋白(LRP)在骨肉瘤(OS)中的表达及与临床病理特点的关系.方法 38例OS及10例正常骨组织的石蜡切片,以P-gp单克隆抗体C219及LRP单克隆抗体LRP56用SABC法进行免疫组化染色,并对有关临床及病理指标综合分析.结果 OS中P-gp及LRP阳性表达率分别为55.26%和42.11%,而正常骨组织均为阴性表达,两组间比较差异有显著意义(P＜0.05).此外,P-gp在转移组及外科分期较高组中的表达率高于未转移组及外科分期较低的病例组(P＜O.05);LRP在＜12岁或＞30岁年龄组中明显高于12～30岁病例组(P＜O.05).崧?1)P-gp与LRP均介导OS的多药耐药(MDR).(2)人OS对化疗不敏感、预后差与OS组织中存在P-gp及LRP有关.(3)P-gp与LRP的表达不相关,分别以独立机制介导OS的MDR.(4)用免疫组化法检测OS的P-gp和LRP,可作为临床常规筛选检测,并为指导制定合理的治疗方案和预后评估提供依据.     

β-榄香烯抗DDP耐药卵巢癌细胞SKOV3/DDP 作用及机制研究

目的:研究β-榄香烯对DDP耐药卵巢癌细胞SKOV3/DDP增殖生长、逆转耐药的作用,以及对耐药细胞中耐药相关蛋白表达的影响。方法:CCK-8法研究β-榄香烯对SKOV3/DDP细胞增殖的抑制作用;克隆形成实验研究β-榄香烯对SKOV3/DDP细胞克隆形成的影响;流式细胞术研究β-榄香烯对SKOV3/DDP细胞凋亡的影响;CCK-8法研究β-榄香烯对SKOV3/DDP细胞产生顺铂(DDP)耐药的逆转指数;Western Blot法研究β-榄香烯对SKOV3/DDP细胞中耐药相关蛋白ABCB1、LRP和P-gp表达水平的影响。结果:β-榄香烯在20、40、80μmol·L^-1时能够抑制SKOV3/DDP细胞的增殖、克隆形成并促进细胞凋亡;β-榄香烯在不具有直接杀伤细胞作用的10μmol·L^-1时即可以逆转SKOV3/DDP细胞对DDP的耐药,其逆转耐药指数为2.58倍;β-榄香烯在20、40、80μmol·L^-1时能够减少耐药相关蛋白ABCB1、LRP和P-gp表达。结论:β-榄香烯能够直接抑制SKOV3/DDP细胞增殖、促进其凋亡并逆转细胞DDP耐药,其作用机制可能与减少耐药相关蛋白ABCB1、LRP和P-gp表达有关。     

活性氧对P-糖蛋白调节作用的研究进展

P-糖蛋白是由多药耐药基因(MDR1)编码的跨膜糖蛋白,介导ATP依赖的多药耐药,能把多种亲脂性外源物质排出胞外。P-gp过表达介导的多药耐药是目前多药耐药发生的主要机制。活性氧(reactive oxygen species,ROS)是细胞内的信号分子,能被多种物质调节升高。近有研究显示多种ROS诱导剂可以下调P-gp的表达,推测某些ROS诱导剂有望成为P-gp抑制剂而成为肿瘤多药耐药逆转剂研究的新方向。     

紫杉醇诱导的人白血病CCRF-CEM多药耐药细胞模型的建立

目的建立稳定的紫杉醇(paclitaxel)诱导的人肿瘤多药耐药细胞系,并对其生物学特点进行评价。方法用亚致死浓度(1/50IC50值)的紫杉醇连续诱导对化疗药物敏感的人急性T淋巴细胞白血病CCRF-CEM细胞,使其成为对紫杉醇耐药的CCRF-CEM/paclitaxel细胞,同时观察CCRF-CEM/paclitaxel细胞对柔红霉素(daunorubicin)和长春碱(vinblastine)的交叉耐药;用相应的单抗和FITC标记的二抗与细胞孵育后,用流式细胞仪分别检测细胞表面和细胞总P糖蛋白(P-gp)、多药耐药相关蛋白1(MRP1)和肺癌耐药相关蛋白(LRP)等表达水平的变化,并用流式细胞仪检测细胞周期和细胞凋亡率的变化。结果CCRF-CEM/paclitaxel细胞传至第90代时,对紫杉醇产生了耐药,耐药倍数约为256.4倍;同时对柔红霉素和长春碱也产生了耐药,耐药倍数约为9.8和2.0倍。与CCRF-CEM细胞比较,CCRF-CEM/paclitaxel细胞表面P-gp和细胞总P-gp表达分别升高了18.8和14.4倍,MRP1和LRP分别升高了2.1和1.2倍;S期细胞比例由(48.3±1.2)%降低至(23.8±0.5)%,细胞凋亡百分率由(7.82±0.19)%减少至(2.47±0.37)%。结论成功建立了稳定的紫杉醇诱导的人CCRF-CEM/paclitaxel多药耐药细胞模型,该模型具有一般肿瘤多药耐药细胞的生物学特点。     

肺癌中多药耐药因子的表达相关性及临床意义的研究

目的 探讨多药耐药因子在肺癌中表达与共表达的水平、相关性及临床意义.方法 采用免疫组化SP技术检测60例肺癌患者组织芯片中P-糖蛋白(P-gp)、多药耐药相关蛋白(MRP)、肺耐药蛋白(LRP)、谷胱苷肽-S转移酶-π(GST-π)等多药耐药因子的表达水平.结果 ①P-gp、MRP、LRP、GST-π阳性表达率分别为53.3%(32/60)、63.3%(38/60)、70.0%(42/60)、80.0%(48/60).②耐药因子在不同病理类型中表达差异有统计学意义(P＜0.05),在NSCLC中表达高于SCLC;在不同TNM分期、不同分化程度间表达差异无统计学意义(P＞0.05).③各耐药因子之间阳性共表达的结果分别为P-gp+MRP:41.6%,P-gp+LRP:35.0%,MRP+LRP:53.3%,MRP+GST-π:50.0%,LRP+GST-π:58.3%,P-gp+GST-π:45.0%,P-gp +MRP+LRP+GST-π:20.0%.其中P-gp与MRP间具有相关性(r=0.756,P＜0.01),P-gp与LRP间具有相关性(r=0.689,P＜0.01),MRP与LRP间具有相关性(r=0.669,P＜0.01),MRP与GST-π间具有相关性(r=0.546,P＜0.01),LRP与GST-π间具有相关性(r=0.848,P＜0.01),P-gp与GST-π具有相关性(r=0.535,P＜0.01).结论 肺癌的多药耐药现象是由多个耐药因子共同参与作用的结果,肺癌多药耐药的发生在肿瘤细胞的病理分型间有差异性,在不同分化程度、不同TNM分期间无差异性.

Abstract：

Objective To study the expression,co-expression, and clinical significance of four multi-drug resistance factors in lung cancer. Methods The P-glycoprotein (P-gp), mullidrug resistance-associated protein ( MRP, lung resistance protein ( LRP), glutathione-S-transferase (GST-π) of 60 lung cancer patients were detected by immunohistochemical methods. Results The positive drug resistance rate of P-gp, MRP, LRP, GST-π was 53.3% (32/60) ,63.3% (38/60) ,70.0% (42/60) ,80.0% (48/60) respectively. Patients with NSCLC had significantly higher expression of the drug resistance factors than those with SCLC. No relation was observed among the expression of drug resistance factors and TNM stage and cell differentiation. The-expression rate was as follows: Pgp + MRP :41.6%, P-gp + LRP :35.0%, MRP + LRP :53.3%, MRP + GST-π:50.0%, LRP + GST-π: 58.3%, Pgp + GST-π:45.0%. P-gp + MRP + LRP + GST-π:20.0%. Among them, significant relation was detected between P-gp and MRP ( rs = 0.756, P ＜ 0. 0 ), between P-gp and LRP ( rs = 0.689, P ＜ 0.01 ), between MRP and LRP (rs = 0.669, P ＜ 0.01 ), between MRP and GST-π( rs = 0.546, P ＜ 0.01 ), between LRP and GST-π ( rs = 0.848, P ＜0.01 ), between P-gp and LRP( rs =0.535 ,P ＜0.01 ). Conclusions The Multi-drug resistance in lung cancer patients is affected by various multidrug resistance factors. The drug resistance factors' expression is related to histology, but not to TNM stage end cell differentiation.     

耐多柔比星S180荷瘤小鼠模型的建立

目的 采用低剂量多柔比星诱导,建立耐多柔比星的S180的荷瘤小鼠模型。方法 建立腹水型S180荷瘤小鼠模型。对荷瘤小鼠反复低剂量应用多柔比星,逐步诱导产生耐多柔比星的S180荷瘤小鼠模型。并通过多柔比星对S180杀伤率、流式细胞术动态检测MDR表达情况等评价模型建立情况。结果 实验组小鼠自用药后1周MDR表达逐渐增高,自第5周后显著性增加(P<0.05),第7周的P-gp表达率是第1周的近10倍。第5周时实验组MDR阳性表达小鼠占66.7%,第7周占77.8%。多柔比星对S180杀伤率逐月降低。经传代后腹水型小鼠S180细胞的表达稳定。结论 本方法简单方便,可用于在体肿瘤多药耐药研究。     

MiR-497对人胃癌细胞株顺铂耐药性的影响和机制

目的:通过建立人胃癌细胞SGC-7901的顺铂耐药细胞株SGC-7901/DDP,探讨miR-497对SGC-7901/DDP耐药性的影响及其机制。方法:体外研究采用顺铂体外逐步加量诱导法建立人胃癌细胞SGC-7901耐药株,并通过检测药物半抑制浓度和耐药基因MDR1、BCRP、MRP1的表达以鉴定耐药细胞株;检测在亲本及耐药细胞中miR-497、MDR1、MRP1、BCRP和凋亡相关基因Bax、Bcl-2的表达水平;miR-497模拟物分别转染SGC-7901/DDP细胞株,利用SRB法和流式细胞术检测转染miR-497模拟物后细胞对顺铂醇的敏感程度和细胞的周期、凋亡的变化,并检测耐药基因和凋亡相关基因的表达。结果:成功建立人胃癌SGC-7901/DDP耐药细胞株,耐药细胞株中耐药基因MDR1、BCRP、MRP1表达均升高,抗凋亡基因Bcl-2升高,凋亡基因Bax下降,miR-497表达下降(P<0.05);miR-497模拟物提高耐药细胞株对顺铂的药物敏感性,凋亡水平增加,细胞周期G₀/G₁期细胞增多(P<0.05),并可抑制耐药细胞中耐药基因的表达,降低Bcl-2/Bax比值(P<0.05)。结论:人胃癌耐药细胞株SGC-7901/DDP的miR-497表达下调;上调miR-497的表达可逆转人胃癌SGC-7901/DDP细胞株对化疗药物顺铂的耐药性。     

Ezrin在胃癌组织中的表达及与P-gp、GST-π、LRP的关系

目的检测埃兹蛋白(Ezrin)、P-糖蛋白(P-gp)、谷胱甘肽-S-转移酶π(GST-π)和肺耐药相关蛋白(LRP)在胃癌组织中的表达,并对Ezrin在胃癌多药耐药(MDR)中的意义进行分析。方法对52例胃癌和36例癌旁组织标本进行免疫组化染色,检测Ezrin与P-gp、GST-π在两种组织中的表达情况。结果胃癌组织中Ezrin、P-gp、GST-π、LRP表达均比癌旁组织增强(P<0.05)。相关分析显示,胃癌组织中Ezrin与P-gp表达存在正相关关系(r=0.3385,P=0.0141),Ezrin与LRP表达存在正相关关系(r=0.3072,P=0.0267),P-gp与LRP表达存在正相关关系(r=0.2986,P=0.0315)。结论 Ezrin在胃癌组织中表达增强,Ezrin可能通过调节P-gp、LRP表达而参与胃癌MDR。     

多药耐药基因在大肠癌组织中的表达和临床研究

目的探讨大肠癌组织中7种多药耐药因子的表达、共表达及与患者临床病理特征的相关性。方法采用微波EnVision免疫组织化学法联合检测63例大肠癌患者癌组织中P-糖蛋白(P-gp)、谷胱甘肽-S转移酶-π(GST-π)、DNA拓扑异构酶(TopoⅡ)、胸苷酸合成酶(TS)、甲基鸟嘌呤甲基转移酶(MGMT)、肺耐药蛋白(LRP)及多药耐药相关蛋白(MRP)的表达水平。结果P-gp、GST-π、TopoⅡ、TS、MGMT、LRP和MRP在大肠癌组织中的阳性表达率分别为54%(34例)、71%(34例)、62%(39例)、67%(42例)、57%(36例)、79%(50例)和30%(19例)。所有的多药耐药因子表达均与患者的年龄、性别无相关。MGMT、LRP的表达与淋巴结转移相关;P-gp、GST-π、TopoⅡ、MRP的表达与组织学分级相关;TS、MGMT、LRP的表达与临床分期相关;P-gp、MGMT的表达与生存期明显相关。结论大肠癌组织表达多种耐药因子,各耐药因子间共表达具有明显相关性。大肠癌耐药由多种耐药基因共同参与,联合检测多项耐药因子有重要的临床意义。     

The reversal effects of piperine and (R)-(+)-citronellal on multidrug resistant breast cancer cells

Multidrug resistance (MDR) in tumor cells can reduce the efficacy of chemotherapy. Overexpression of transporters is an important mechanism for MDR. P-glycoprotein (P-gp) is an ATP-binding cassette transporter frequently expressed in multidrugresistant tumor cells, inducing MDR. To reverse P-gp dependent MDR, anticancer drugs can be administered with P-gp inhibitors. Piperine and (R)-(+)-citronellal both are P-gp inhibitors from dietary sources. In the present study, we aimed to evaluate the MDR reversal effects of piperine and (R)-(+)-citronellal in multidrug resistant MCF-7/DOX cells. The results of cytotoxicity studies indicated that piperine and (R)-(+)-citronellal both could abate the resistance of MCF-7/DOX after 72-h incubation. After 72-h incubation, piperine could dose-dependently down-regulate the MDR1 expression at the mRNA level, while (R)-(+)-citronellal had no effect on the MDR1 expression. Therefore, piperine and (R)-(+)-citronellal both could reverse MDR in MCF-7/DOX cells, and the reversal effect of piperine was related to dose-dependent down-regulation of the MDR1 expression at the mRNA level.     

Establishment and characterization of adriamycin-resistant human colorectal adenocarcinoma HCT-15 cell lines with multidrug resistance

The multidrug resistance (MDR) phenotype, either intrinsic and/or acquired, is discussed in relation to several MDR-associated markers such as P-glycoprotein (P-gp) encoded by mdr1, multidrug-resistance-associated protein (MRP) encoded by MRP and lung-resistance-associated protein (LRP) encoded by LRP. Well-characterized in vitro models are required to elucidate the mechanisms of MDR. The aim of the present study is the establishment of a drug-resistant subline from human colorectal adenocarcinoma HCT-15 that intrinsically expresses moderate levels of P-gp, MRP and LRP. Three adriamycin-resistant sublines (HCT-15/ADM1, HCT-15/ADM2 and HCT-15/ADM2-2) were established by stepwise exposure in growth medium that was supplemented with 25-200 ng/ml adriamycin-resulting in a 2.2- to 7.8-fold increase in IC(50) values by using the XTT assay. They were cross-resistant to MDR-related drugs, epirubicin, mitoxantrone, vincristine, etoposide and taxol, but not the MDR-unrelated drug, mytomycin C. The resistance to adriamycin was confirmed in vivo by a lack of sensitivity in athymic nude mice. Gene expression data for mdr1/P-gp, MRP/MRP and LRP/LRP on both mRNA and protein levels demonstrated that the molecules contributing to MDR in resistant sublines are mainly P-gp and partially MRP. The newly established adriamycin-resistant sublines of HCT-15 will provide clinically relevant tools to investigate how to overcome drug resistance and elucidate possible mechanisms of acquired MDR in human colon cancer.     

Verotoxin-1 treatment or manipulation of its receptor globotriaosylceramide (gb3) for reversal of multidrug resistance to cancer chemotherapy

A major problem with anti-cancer drug treatment is the development of acquired multidrug resistance (MDR) of the tumor cells. Verotoxin-1 (VT-1) exerts its cytotoxicity by targeting the globotriaosylceramide membrane receptor (Gb3), a glycolipid associated with multidrug resistance. Gb3 is overexpressed in many human tumors and tumor cell lines with inherent or acquired MDR. Gb3 is co-expressed and interplays with the membrane efflux transporter P-gp encoded by the MDR1 gene. P-gp could act as a lipid flippase and stimulate Gb3 induction when tumor cells are exposed to cancer chemotherapy. Recent work has shown that apoptosis and inherent or acquired multidrug resistance in Gb3-expressing tumors could be affected by VT-1 holotoxin, a sub-toxic concentration of the holotoxin concomitant with chemotherapy or its Gb3-binding B-subunit coupled to cytotoxic or immunomodulatory drug, as well as chemical manipulation of Gb3 expression. The interplay between Gb3 and P-gp thus gives a possible physiological approach to augment the chemotherapeutic effect in multidrug resistant tumors.