直肠癌组织耐药相关蛋白的表达及川芎嗪联合化疗的意义

目的探讨直肠癌组织耐药相关蛋白的表达及川芎嗪联合化疗的意义。方法从耐药直肠癌患者手术切除直肠癌组织上分离制备细胞悬液,并利用流式细胞仪和Western-Blotting研究P-170、多药耐药相关蛋白（Multidrug resistance protein,MRP）、肺耐药相关蛋白（Lung re-sistance associated protein,LRP）等耐药蛋白的表达情况,以阐明耐药直肠癌细胞的耐药机理,另外应用中药川芎嗪对5-FU进行增敏实验,再联合5-FU对耐药直肠癌患者进行化疗,并与常规化疗进行疗效比较。结果耐药直肠癌细胞的耐药机理主要是通过上调P-170、MRP等耐药蛋白的表达实现,而中药川芎嗪则可以通过下调P-170、MRP等耐药蛋白的表达来增敏耐药直肠癌细胞。结论川芎嗪可以增加耐药直肠癌细胞对化疗药物的敏感性,川芎嗪联合化疗可以有效增加耐药患者的近期有效率,值得临床推广。     

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。     

中药逆转肿瘤多药耐药非经典机制的研究进展

目前认为,由肿瘤多药耐药(MDR)基因编码的P-糖蛋白(P-gp)过度表达介导的药物外排是产生MDR的经典机制[1]。除此外,MDR还与多药耐药相关蛋白(MRP)、谷光甘肽-S-转移酶(GST)、拓扑异构酶Ⅱ(TopoⅡ)、细胞凋亡等多种非经典机制密切相关。由于中药不同于一般的化学制剂只有单一的逆转作用靶点,一种中药单体就是一个复杂的化学分子复合体,往往同时具有数种逆转机制,故从中药中筛选有效的MDR逆转剂已成为近年的研究热点。然而,中药逆转肿瘤MDR研究现存的主要问题是无论何种剂型,其研究机制偏于单一,大多数的研究主要集中在经典机制上。…     

汉防己甲素逆转人肝癌耐药细胞株多药耐药性的研究

目的研究汉防己甲素对人肝癌多药耐药细胞株Hep-3B／ADM耐药性的逆转作用及其机制。方法通过阿霉素（ADM）浓度梯度递增诱导法，建立人肝癌多药耐药细胞株Hep-3B／ADM。MTT法检测细胞对化学疗法药物的敏感性；流式细胞仪检测细胞表面多药耐药基因表达产物P-170及分析细胞内若丹明123染剂相对荧光强度。结果汉防己甲素（0．10～1．00μmol／L）可逆转肝癌耐药细胞的耐药性；汉防己甲素明显降低细胞表面P-170的表达。结论汉防己甲素具有增强阿霉素对Hep-3B／ADM细胞的毒性作用，其作用机制与逆转多药耐药基因有关。     

尼美舒利对人乳腺癌MCF-7/ADM细胞的耐药逆转作用

目的：研究尼美舒利对人乳腺癌敏感细胞株MCF-7／S及多药耐药细胞株MCF-7／ADM的影响，初步探讨其逆转人乳腺癌耐药的机制。方法：用MTT比色法测定细胞生长抑制率、流式细胞仪检测细胞内Rh123浓度和P-170、GST-π表达水平变化。结果：尼关舒利对MCS-7／S和MCF-7／ADM细胞的生长抑制呈明显时间剂量依赖关系。但尼关舒利对MCF-7／ADM细胞效应强度明显弱于MCF-7／S细胞。尼美舒利能提高MCF-7／ADM细胞内Rh123荧光强度，下调P-170和GST-π的水平（P〈0．05）。结论：尼美舒利对人乳腺癌MCF-7／ADM的耐药有一定逆转作用，作用机制可能与P-170和GST-π的水平下调有关。     

五味子醇甲逆转MRP1多药耐药机制的研究

肿瘤的多药抗药性（muhidrug resistance,MDR）是肿瘤化疗失败的主要原因之一。我们及他人的研究已证实五味子醇甲（Schisandrol A）可以逆转P—gP介导的耐药。本实验中,我们以MRP介导的白血病多药耐药细胞株HL-60／ADR和HL-60／MRP为研究对象,探讨了五味子醇甲逆转MRP耐药的作用机理,以进一步阐明耐药发生机制。     

尼美舒利对人胃癌SGC7901 VCR细胞耐药逆转作用

目的 研究尼美舒利对人胃癌敏感细胞株SGC7901及多药耐药细胞株SGC7901VCR的影响,初步探讨其逆转人胃癌耐药的机制。方法 MTT法测定细胞生长抑制率、流式细胞仪检测细胞内Rh123浓度和P-170、GST-π表达水平变化。结果 尼美舒利对SGC7901及SGC7901VCR细胞的生长抑制呈明显时间剂量依赖关系。但尼美舒利对SGC7901VCR细胞效应强度明显弱于SGC7901细胞。尼美舒利能提高SGC7901VCR细胞内Rh123荧光强度,下调P-170和GST-π的水平(P＜0.05)。结论 尼美舒利对人胃癌SGC7901VCR耐药有一定逆转作用,作用机制可能与下调P-170和GST-π的水平有关。     

槐耳颗粒逆转人乳腺癌细胞MCF-7耐药的初步机制

目的研究槐耳颗粒逆转乳腺癌细胞株MCF-7耐药的初步机制。方法使用四甲基偶氮唑蓝（MTT）比色法测定敏感／耐药乳腺癌细胞MCF-7-S／A对单药阿霉素（ADM）和槐耳颗粒的药物毒性,耐药倍数和槐耳颗粒对MCF-7／A的耐药逆转倍数,分别采用荧光定量逆转录-聚合酶链反应和免疫组化SP法测定多药耐药基因mdr1、多药耐药相关蛋白基因MRP的mRNA和其相应的表达产物P-gp、MRP蛋白,在MCF-7／S及非细胞毒性剂量的槐耳颗粒处理前后MCF-7／A上的表达。结果非细胞毒性剂量（0．01mg／ml）的槐耳颗粒能显著降低ADM对MCF-7／A的IC50（5．06μm）,与逆转前MCF-7／A的IC50（25．8μm）,相比差异有统计学意义（P〈0．01）,其逆转倍数为5．1倍;0．01mg／ml的槐耳颗粒使MCF-7／A细胞的耐药基因mdr1、MDR-1的mRNA以及相应的P-gp、MRP蛋白的表达水平均下调,与未加槐耳颗粒处理的对照组MCF-7／A相比有显著性差异（P〈0．01）。结论非细胞毒性剂量槐耳颗粒具有逆转MCF-7／A细胞耐药性的作用,逆转机制和其耐药基因mdr1、MDR-1的mRNA以及相应的P-gp、MRP蛋白的表达水平下调相关,暗示槐耳颗粒是一种有潜力的耐药逆转剂。     

耐阿霉素人骨肉瘤细胞株的建立及其耐药机制探讨

目的诱导并建立耐阿霉素(ADM)的人骨肉瘤细胞株并探讨其耐药机制。方法采用逐步增加药物剂量冲击诱导方法诱导人成骨肉瘤原代Saos-2细胞株;MTT法检测原代与耐药细胞株对ADM、顺铂(DDP)、甲氨蝶呤(MTX)、异环磷酰胺(IFO)、表柔比星(EPI)、比柔比星(THP)、紫杉醇(Paclitaxel,PTX)药物敏感性;利用光学显微镜、透射电镜观察细胞形态及超微结构变化;RT-PCR和IHC法分别检测多药耐药基因1(MDR1)、多药耐药相关蛋白(MRP)基因及其相应蛋白(P-gp)、MRP的表达。结果经167d的诱导,建立Saos-2/ADM1、Saos-2/ADM4细胞株,其对ADM的耐药指数分别为原代细胞株的49.8和74.6倍;耐药细胞株对MTX、EPI、THP、PTX亦产生不同程度的交叉耐药(P<0.05),对DDP仍然敏感(P>0.05);光镜观察Saos-2/ADM1、Saos-2/ADM4细胞株细胞体积增大,多核现象较原代Saos-2细胞株明显增加;透射电镜显示Saos-2/ADM1、Saos-2/ADM4细胞株表面突起较原代Saos-2细胞株减少、且核仁增大增多;细胞生长曲线显示耐药细胞株增殖能力下降。MDR1mRNA、MRPmRNA和P-gp、MRP在各耐药细胞株表达阳性。结论MDR1 mRNA、MRP mRNA及其相应蛋白参与了耐药细胞株耐药的形成,这些骨肉瘤耐药细胞株为进一步研究骨肉瘤耐药特征及逆转方法打下了基础。     

肿瘤多药耐药机制及逆转药物的研究进展

导致肿瘤多药耐药的机制很复杂,主要涉及有：ATP结合盒型转运蛋白超家族、DNA甲基化、细胞凋亡、拓扑异构酶Ⅱ、谷胱甘肽解毒系统及相关多药耐药信号通路等,这些机制单独或共同存在而导致耐药。逆转肿瘤多药耐药的方法主要有：化疗增敏剂、中药逆转剂和基因工程技术逆转耐药等。本文就肿瘤多药耐药机制的研究进展及逆转耐药的方法作一综述。     

Glucuronidation as a mechanism of intrinsic drug resistance in colon cancer cells: contribution of drug transport proteins

We have recently shown that drug conjugation catalysed by UDP-glucuronosyltransferases (UGTs) functions as an intrinsic mechanism of resistance to the topoisomerase I inhibitors 7-ethyl-10-hydroxycamptothecin and NU/ICRF 505 in human colon cancer cells and now report on the role of drug transport in this mechanism. The ability of transport proteins to recognise NU/ICRF 505 as a substrate was evaluated in model systems either transfected with breast cancer-resistance protein 1 (Bcrp1), multidrug-resistance protein 2 (Mrp2) or Mrp3, or overexpressing MRP1 or P-170 glycoprotein. Results from chemosensitivity assays suggested that NU/ICRF 505 was not a substrate for any of the above proteins. In drug accumulation studies in human colon cancer cell lines NU/ICRF 505 was taken up avidly and retained in cells lacking UGTs (HCT116), whereas, following equally rapid uptake, it was cleared rapidly from cells displaying UGT activity (HT29) as glucuronide metabolites. HT29 cells were shown to express MRP1 and 3, but not P-170 glycoprotein, MRP2 or breast cancer-resistance protein. The major glucuronide of NU/ICRF 505 inhibited ATP-dependent transport of estradiol 17-beta-glucuronide in Sf9 insect cell membrane vesicles containing MRP1 or MRP3, while co-incubation of HT29 cells with the MRP antagonist, MK571, significantly restored intracellular concentrations of NU/ICRF 505. These data lead us to conclude that the presence of a glucuronide transporter is essential for glucuronidation to represent a major de novo resistance mechanism and that UGTs will contribute more as a primary resistance mechanism when the parent drug (e.g. NU/ICRF 505) is not itself recognised by transport proteins.     

中药活性成分逆转结直肠癌耐药的药理作用机制研究进展

结直肠癌是我国第3大常见癌症,发病率、死亡率逐年上升。由于耐药导致结直肠癌化疗失败的报道不断增多,迫切需要寻找新的药物作为化疗药物的增敏剂。以中药活性成分为研究重点,发现姜黄素、白藜芦醇、人参皂苷等中药活性成分可以通过调控相关蛋白表达、自噬、上皮间充质转化、癌症干细胞、有氧糖酵解等途径逆转结直肠癌耐药性。对逆转结直肠癌耐药性的中药活性成分及其药理作用机制加以总结,以期为结直肠癌治疗提供更多选择。     

荜茇酰胺对人肺癌A549/DDP细胞耐药性的逆转作用

目的:研究荜茇酰胺对人肺癌A549/顺铂(DDP)细胞耐药性的逆转作用。方法:A549/DDP细胞经0、20、30μmol/L荜茇酰胺作用48 h后,用MTS法检测肿瘤细胞抑制率;流式细胞术检测肿瘤细胞凋亡、细胞周期、P-糖蛋白(P-gp)表达和肿瘤细胞内罗丹明Rht123含量的变化;Western blotting法检测多药耐药基因(MDR)1、多药耐药相关蛋白(MRP)1、DNA拓扑异构酶(Top)Ⅱ、谷胱甘肽S-转移酶(GST)-π、凋亡抑制蛋白Survivin、周期蛋白依赖性蛋白激酶(CDK)1和蛋白激酶(PK)Cζ蛋白表达;实时荧光聚合酶链反应(RT-PCR)法检测MDR1、MRP1、Top-II、GST-π、Survivin和CDK1 m RNA表达;酶标仪检测含半胱氨酸的天冬氨酸蛋白水解酶(Caspase)-3、8活性。结果:A549/DDP细胞经0、20、30μmol/L荜茇酰胺作用48 h后,DDP对肿瘤细胞增殖的抑制率明显升高;与0μmol/L比较,20、30μmol/L荜茇酰胺作用48 h后,DDP导致的细胞凋亡率和G2期/M期明显升高,P-gp表达明显减弱,Rh-123浓度明显增加,MDR1、MRP1、Top-II、GST-π、Survivin、CDK1和PKCζ蛋白表达明显减弱,MDR1、MRP1、Top-Ⅱ、GST-π、Survivin、CDK m RNA表达明显减弱,Caspase-3、8的活性明显增强。结论:荜茇酰胺可逆转人肺癌A549/DDP细胞DDP耐药性,可能与其调节多药耐药相关基因表达有关。     

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.     

肺癌组织及外周血多药耐药基因相关蛋白的表达及其相关性研究

目的 检测多药耐药相关蛋白(MRP)和肺耐药蛋白(LRP)在肺癌组织及外周血中的表达及其相关性,探讨其临床意义.方法 采用逆转录一聚合酶链反应(RT-PCR)检测47例患者肺癌组织及外周血的MRP、LRP mRNA的表达水平.结果 肺癌组织及外周血,MRP mRNA的阳性表达率分别为74.5％(35/47)和70.2％...     

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.     

Modulation of multidrug resistance efflux pump activity to overcome chemoresistance in cancer

Early publications using cultured cancer cells immediately recognized the phenomenon of resistance to anticancer agents. However, it was not until 1973 that it was first demonstrated that a major factor in the resistance of cancer cells was that of reduced drug accumulation. This year marks the 30th anniversary of the discovery by Juliano and Ling that P-glycoprotein mediates this active efflux of chemotherapeutic drugs from cancer cells. Since this seminal finding, the investigation of P-glycoprotein (MDR1, ATP binding cassette [ABC]B1) has proceeded with great vigour. However, it soon became apparent that P-glycoprotein was not expressed in all drug-resistant cells that displayed an accumulation deficiency, which led to the discovery of other ABC transporters involved in drug efflux. In 1992, the multidrug resistance-associated protein (MRP1, ABCC1) was identified in small cell lung cancer followed by breast cancer resistance protein (mitoxantrone resistance protein, ABCG2) in 1999. After three decades of research, can we confidently define the contribution of multidrug resistance transporters to chemoresistance and do we have clinically useful drugs to sensitise cancers?