三维培养药敏实验测定的结直肠癌化疗敏感性与多药耐药基因蛋白表达的关系

背景与目的：目前肿瘤化疗疗效尚不理想,通过预测个体肿瘤对化疗药物的敏感性来指导临床治疗,有可能提高化疗疗效。本研究通过三维培养药敏实验测定结直肠癌的药物敏感性,并分析与肿瘤组织多药耐药基因表达产物水平的关系。方法：应用三维培养体外药敏实验技术,检测表阿霉素、顺铂、草酸铂、氟尿嘧啶（5-fluorouracil,5-FU）、泰素帝、伊立替康6种单药和5-FU＋表阿霉素＋顺铂、5-FU＋伊立替康、5-FU＋草酸铂、5-FU＋泰素帝＋顺铂4组联合用药对22例结直肠癌组织的抑制率,抑制率大于30％定义为敏感,计算敏感率。应用逆转录聚合酶链反应和免疫组化法测定结直肠癌组织中MDR1、MRP1、ABCG2基因蛋白表达水平;用Spearman相关分析法分析肿瘤药物敏感性和多药耐药蛋白表达的相关性。结果：单药组抑制率最高为草酸铂（17．5％）,敏感率最高为5-FU（36．4％）;联合用药组抑制率最高为5-FU＋草酸铂（54．1％）,敏感率最高为5-FU＋表阿霉素＋顺铂（71．4％）和5-FU＋泰素帝＋JJRSt3（71．4％）;联合用药组抑制率和敏感率均高于单药组（P〈0．05）。MDR1、MRP1、ABCG2mRNA的阳性率分别为88．9％、55．6％、55．6％：MDR1、MRP1、ABCG2蛋白的阳性率分别为55．6％、33.3％、50．0％;多药耐药基因MDR1、MRP1、ABCG2mRNA和蛋白的表达无相关性（P〉0．05）。ABCG2蛋白高表达与结直肠癌对表阿霉素的耐药有相关性（P〈0．05）。结论：结直肠癌多药耐药蛋白表达与肿瘤药物敏感性有一定相关性;结合三维培养药敏实验和多药耐药基因表达产物水平检测,有可能对个体肿瘤的化疗敏感性进行预测,筛选化疗敏感药物。     

非小细胞肺癌中多药耐药基因的表达及意义

探讨多药耐药基因(MDR1)和多药耐药相关蛋白基因(MRP)在非小细胞肺癌(NSCLC)中的表达、意义及相关关系。方法:采用原位分子杂交对113例NSCLC组织中MDR1和MRP基因mRNA的表达进行检测。结果:MDR1和MRP基因mRNA在NSCLC组织中的阳性表达率分别为51.3%(58/113)、80.5%(91/113),二者与NSCLC肿瘤组织类型、分化程度、淋巴结转移、TNM分期等无关(P>0.05)。MDR1和MRP的协同阳性(MDR1⁺/MRP⁺)表达率为48.7%(55/113),二者在NSCLC中的表达之间存在明显相关(P<0.01)。结论:MDR1和MRP是NSCLC原发性多药耐药的重要参与因素,二者联合检测对临床NSCLC的化疗具有指导意义。     

胃癌多药耐药表达与凋亡指数相关性

目的：研究多药耐药（multidrug resistance,MDR)基因表达与凋亡指数（apoptosis index,AI)在胃癌中的表达及与预后的关系,探讨它们之间相关性。方法：应用抗鼠抗人P-gp。GST-π和拓扑异构酶Ⅱ（topoisomeraseⅡ,ToPoⅡ）单克隆抗体对80例胃癌进行免疫组化研究,用Tunel法测定细胞凋亡指数。结果：AI、P-糖蛋白（P-glycoprotein,P-gp)表达与临床分期呈正相关（P＜0.05),谷胱甘肽转移酶π（glutathione-s-transferase-π,GST-π）表达强度与生存期相关（P＜0.05),ToPoⅡ表达与组织分化程度相关（P＜0.05),其中P-gp表达与GST-π高度相关（P＞0.01)。GST-π与ToPoⅡ表达相关（P＜0.05),而细胞凋亡指数与MDR表达不相关（P＞0.05)。结论：MDR基因产物表达（P-gp,GST-π和ToPoⅡ）具相关性,但与Al不相关。MDR表达可能由一系列相同基因组调控,而细胞凋亡则可能属于不同基因调控系列。     

多药耐药相关蛋白和肺耐药蛋白在胃癌组织中的表达

目的　探讨多药耐药相关蛋白 (MRP)和肺耐药蛋白 (LRP)在胃癌组织中的表达及其临床意义。方法　应用免疫组化S -P法检测 90例胃癌组织和 3 0例正常胃黏膜中MRP和LRP的表达情况。结果　 90例胃癌组织中的MRP、LRP阳性表达率分别为 92 .2 %和 93 .3 % ,均高于正常胃黏膜的阳性表达率 (P <0 .0 5 ) ,在高中分化腺癌中的阳性表达率高于低分化腺癌和黏液癌 (P <0 .0 5 ) ,不同浸润程度及是否有淋巴结转移者的阳性表达率相互比较无显著性差异 (P >0 .0 5 )。结论　MRP、LRP在胃癌组织中均呈高表达 ,均在胃癌原发性多药耐药中起重要作用     

多药耐药相关蛋白（MRP）的表达与肿瘤放化疗的敏感性

多药耐药(multidrug resistance，MDR)的产生是导致肿瘤产生耐药和化疗失败的主要原因之一，耐药现象是肿瘤化疗所面临的最常见和最棘手的问题，其结果是肿瘤病人对化疗无效或导致复发。多药耐药性是指抗某种细胞毒药物的耐药细胞系，对许多结构上无关和作用机制上不同的其他细胞毒药物产生交叉抗药性。实验研究表明，MDR包括三种表现形式：①典型MDR，     

胃癌多药耐药相关蛋白mRNA表达及临床意义

目的 研究胃癌组织中MRP1 mRNA、MRP2 mRNA表达水平及其临床意义。方法 常规石蜡包埋切片原位杂交染色法。结果 50例胃癌MRP1 mRNA和MRP2 mRNA表达阳性率分别为64％和68％,其评分分别为(3.4±1.6)和(3.5±1.4)。高分化腺癌和区域淋巴结未转移癌MRP1 mRNA、MRP2 mRNA表达阳性率及其评分均明显高于未分化癌和伴淋巴结转移癌,差异均有显著性或高度显著性(P<0.05或P<0.01)。结论:MRP1 mRNA和MRP2 mRNA表达水平对了解胃癌发生发展、生物学行为和预后,以及指导化疗均有重要意义。     

MDR1基因稳定表达的人肝癌多药耐药细胞株的建立

目的 建立多药耐药基因(MDR1)稳定表达的人肝癌Bel-7402耐药细胞株，为应用RNA干扰技术逆转肿瘤多药耐药基因的表达提供实验模型。方法 应用阿霉素(ADM)长期培养筛选建立Bel-7402耐药细胞株，应用MTT法、流式细胞仪(FCM)及逆转录聚合酶链反应(RT—PCR)对该细胞株相关特性(耐药范围、致死剂量、p-糖蛋白功能及其表达阳性率、MDR1基因检测)进行比较研究。结果 经MTT法检测，耐药细胞株耐药性明显增高，FCM检查发现从敏感细胞到耐药细胞，其阿霉素潴留功能由77．7％降至25．1％，P-糖蛋白(P—gp)阳性率由1．4％升高至54．0％，RT-PCR检查显示该细胞中MDR1 mRNA呈高表达。结论 成功建立了稳定表达MDR1基因的人肝癌Bel-7402耐药细胞株，该细胞中P—gp呈高表达，稳定性好。     

多药耐药相关蛋白的生物学特性与作用机制的研究进展

多药耐药性相关蛋白（MRP1）是ATP结合的盒式（ABC）膜转运蛋白家族成员,基因敲除实验表明MRP1存在与否不影响小鼠正常的生存和各项生理指标,生理条件下,它可能作为耗能泵游离的谷胱甘肽和某种尚不了解的内源性代谢物一起泵出细胞外,维持细胞外的还原环境。MRP1通过介导细胞内药物排出,改变药物细胞内分布引起肿瘤耐药。     

多药耐药相关蛋白基因与肿瘤耐药

多药耐药相关蛋白基因与肿瘤耐药徐萌综述李金瀚审校第一军医大学附属南方医院肿瘤科（广州市５１０５１５）多药耐药（ｍｕｌｔｉｄｒｕｇｒｅｓｉｓｔａｎｃｅ，ＭＤＲ）的产生是导致肿瘤产生耐药和化疗失败的原因之一。实验研究表明，ＭＤＲ包括三种表现形式：１）典型...     

肺耐药蛋白与胃癌多药耐药

肺耐药蛋白(LRP)是较早发现与恶性肿瘤多药耐药有密切关系的多药耐药基因,在大多数具有分泌功能的正常组织中有表达,参与正常机体组织的分泌和细胞解毒功能.LRP还在许多恶性肿瘤组织包括胃癌组织中也可以有高表达,并且与恶性肿瘤患者的预后有一定的相关性.LRP主要是通过阻止化疗药物进入细胞核内及将进入细胞内的化疗药物泵出细胞外两种方式发挥多药耐药作用.     

Diagnostics of multidrug resistance in cancer

Multidrug resistance (MDR), caused by the overexpression of two membrane proteins, MDR1-Pgp and/or MRP, is a major obstacle in the chemotherapy of cancer. The proper laboratory diagnosis of clinical multidrug resistance is still an unresolved question, and this uncertainty, in a vicious cycle, does not allow the correct evaluation of the clinical relevance of the MDR phenomenon. Moreover, inefficient MDR diagnostics hinders the de velopment of effective resistance-modulation strategies. In this review, after describing the basic features of the MDR drug pump proteins, the currently employed diagnostic methods are discussed. We suggest that a quantitative, functional method developed in our laboratory may provide a major help in the laboratory assessment of cancer MDR.     

Dose response curve of paclitaxel measured by histoculture drug response assay

Dose response curves of paclitaxel were measured by histoculture drug response assay (HDRA) in 11 lung cancer patients. Inhibition rates of paclitaxel at several concentrations were measured and fitted to the sigmoid dose response curve, using non-linear least square analysis, with fitting equation y=A (1-1/(1+exp (b (x-log (ED50)). Parameters A, b, and ED50 were 88.3+/-6.0 (80.0-100.0) %, 9.57+/-4.32 (2.25-15.0), and 26.8+/-8.1 (15.0-41.0) microg/ml, respectively. The parameter b was lower in well-differentiated tumors compared with moderately and poorly-differentiated tumors. Dose response curves of paclitaxel could be measured by HDRA in lung cancer. This method provides us more information for drug sensitivity than the usual HDRA method. This may lead to the improved accuracy of HDRA.     

INFLUENCE OF NEOADJUVANT INTRAARTERIAL INFUSION CHEMOTHERAPY ON APOPTOSIS AND MULTIDRUG RESISTANCE ASSOCIATED GENES OF ENDOMETRIAL CANCER

Many researches have proved that neoadjuvantintraarterial infusion chemotherapy (NIAC) is a useful method for the treatment of uterine cervical cancer[1, 2]while there are few reports about endometrial cancer[3Apoptosis has been shown to occur in various tumors in response to chemotherapeutic agents. It is not only related to the tumor response to chemotherapy, but also closely associated with the multidrug resistance[4, 5]. To date, no data have become available that shed light on the timin…     

Study on chemosensitivity of oral squamous cell carcinomas by histoculture drug response assay

The aim of this study was to evaluate the reliability and utility of a histoculture drug response assay (HDRA) for treatment of squamous cell carcinoma in the oral cavity. Nineteen patients with squamous cell carcinoma of the oral cavity were assessed. Tumor tissue samples were histocultured on Gelfoam sponge gels in 24-well plates, followed by treatment with 5-fluorouracil (5-FU, 300 microg/ml), cisplatinum (CDDP, 20 microg/ml), 4-0-tetrahydropyranyl adriamycin (THP, 4.6 microg/ml), bleomycin (BLM, 20 microg/ml), adriamycin (ADM, 15 microg/ml) and docetaxel (TXT, 100 microg/ml). The controls were cultured without drug treatment. After completion of the culture, the relative cell survival in the tumors was determined using an MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H tetrazolium bromide) assay. The inhibition rate was calculated, and sensitivity was defined as a tumor inhibition rate greater than 60% for 5-FU, 40% for TXT, and 50% for the other drugs. All cases were successfully evaluated by the HDRA, and no apparent relationships between the chemosensitivity test results and clinico-histopathological characteristics were seen. CDDP tended to be sensitive, whereas 5-FU, THP, and BLM tended to show resistance in many cases. A good correlation was obtained between the chemosensitivity test results and clinical response. In conclusion, HDRA is a useful method for selection of an anticancer agent for individual oral cancer patients, because of its ease of evaluation and high predictability.     

Reversal of breast cancer resistance protein-mediated drug resistance by tryprostatin A

MDR in human cancers is one of the major causes of failure of chemotherapy. A member of the superfamily of ABC transporters, BCRP, was demonstrated to confer an atypical MDR phenotype to tumor cells. To overcome the BCRP-mediated drug resistance, the fungal secondary metabolite TPS-A, a diketopiperazine, was analyzed with regard to its potency to reverse the BCRP-mediated drug-resistant phenotype. At concentrations of 10-50 microM, TPS-A reversed a mitoxantrone-resistant phenotype and inhibited the cellular BCRP-dependent mitoxantrone accumulation in the human gastric carcinoma cell line EPG85-257RNOV, the human breast cancer cell line MCF7/AdrVp (both exhibiting acquired BCRP-mediated MDR) and the BCRP cDNA-transfected breast cancer cell line MCF-7/BCRP clone 8. No cytotoxicity was seen at effective concentrations. These data indicate that TPS-A is a novel BCRP inhibitor.     

人肝癌顺铂耐药细胞系SK-Hepl/CDDP的建立

背景与目的:多药耐药是肿瘤治疗的主要障碍,本研究旨在建立人肝癌多药耐药细胞株SK-Hep1/CDDP,并对其生物学特性及发生多药耐药的可能机制进行初步评价.方法:采用大剂量冲击,间歇诱导法获得人肝癌顺铂(Cisplatin-CDDP)多药耐药系SK-Hep1/CDDP;CCK-8法检测药物敏感性,计算半数抑制浓度(IC_(50))和耐药指数(RI);Western blot检测多药耐药基因(MDR1,ABCB1)、多药耐药相关蛋白1(MRP-1,ABCC1)、多药耐药相关蛋白2(MRP-2,ABCC2)、Bax蛋白的表达,以及加入MDR1抑制剂CsA对肝癌细胞MDR1蛋白的表达影响:流式细胞仪(FCM)检测细胞周期及凋亡率.结果:历时6个月建成SK-Hep1/CDDP细胞株,其对CDDP的耐药指数为13.76,并对盐酸阿霉素(doxombicin, DOX)、氟尿嘧啶(5-Fluororacil,5-Fu)等多种抗肿瘤药物交叉耐药:Western blot发现SK-Hep1/CDDP与亲本细胞相比MDR1、MRP-1、MRP-2的表达明显升高(P<0.01),Bax蛋白表达明显降低(P<0.01),加入小剂量环孢素A对肝癌细胞MDR1蛋白的表达无影响(P>0.05);细胞周期分析发现相对于亲本SK-Hep1细胞[G_1期为(59.83±3.28)%,S期为(27.91±2.16)%,G_2/M期为(12.14±3.36)%],SK-Hep1/CDDP耐药细胞[G_1期为(37.50±5.05)%,S期为(42.20±2.65)%,G_2/M期(20.67±5.69)%]的G_2/M,S期比例增加.G_1期比例减少,两组相比差异均有统计学意义(P<0.01);流式细胞仪分析表明CDDP对耐药细胞SK-Hep1/CDDP的凋亡率明显减少,加入MDR1抑制剂干预后可明显增加CDDP对SK-Hep1/CDDP细胞的凋亡率.结论:成功建立MDR细胞株SK-Hep-/CDDP,其耐药机制可能与MDR1、MRP-1、MRP-2蛋白的表达增加,Bax蛋白表达降低及降低化疗药物诱导肿瘤细胞的凋亡作用相关.     

人肝癌顺铂耐药细胞系SK-Hep1/CDDP的建立

背景与目的:多药耐药是肿瘤治疗的主要障碍,本研究旨在建立人肝癌多药耐药细胞株SK-Hep1/CDDP,并对其生物学特性及发生多药耐药的可能机制进行初步评价。方法:采用大剂量冲击,间歇诱导法获得人肝癌顺铂(Cisplatin,CDDP)多药耐药系SK-Hep1/CDDP;CCK-8法检测药物敏感性,计算半数抑制浓度(IC50)和耐药指数(RI);Western blot检测多药耐药基因(MDR1,ABCB1)、多药耐药相关蛋白1(MRP-1,ABCC1)、多药耐药相关蛋白2(MRP-2,ABCC2)、Bax蛋白的表达,以及加入MDR1抑制剂CsA对肝癌细胞MDR1蛋白的表达影响;流式细胞仪(FCM)检测细胞周期及凋亡率。结果:历时6个月建成SK-Hep1/CDDP细胞株,其对CDDP的耐药指数为13.76,并对盐酸阿霉素(doxorubicin,DOX)、氟尿嘧啶(5-Fluororacil,5-FU)等多种抗肿瘤药物交叉耐药;Westernblot发现SK-Hep1/CDDP与亲本细胞相比MDR1、MRP-1、MRP-2的表达明显升高(P<0.01),Bax蛋白表达明显降低(P<0.01),加入小剂量环孢素A...     

Inhibition of P-glycoprotein and multidrug resistance protein 1 by dietary phytochemicals

PURPOSE: For the development of a safe and effective dual inhibitor of anticancer drug efflux transporters P-glycoprotein and multidrug resistance protein 1 (MRP1) to conquer multidrug resistance, we investigated the effects of dietary phytochemicals on the functions of P-glycoprotein and MRP1. METHODS: The effects of dietary phytochemicals on the functions of P-glycoprotein and MRP1 were investigated using P-glycoprotein-overexpressing human carcinoma KB-C2 cells and human MRP1 gene-transfected KB/MRP cells. The effects of natural compounds found in dietary supplements, herbs, and foods such as sesame, ginkgo, soybean, and licorice were evaluated. RESULTS: The accumulation of daunorubicin, a fluorescent substrate of P-glycoprotein, increased in the presence of sesamin, ginkgolic acid, matairesinol, glycyrrhetinic acid, glabridin, and phyllodulcin in KB-C2 cells. Glycyrrhetinic acid and matairesinol also increased the accumulation of calcein, a fluorescent substrate of MRP1, in KB/MRP cells. KB-C2 and KB/MRP cells were sensitized to anticancer drugs by glycyrrhetinic acid, showing that glycyrrhetinic acid reverses multidrug resistance. The verapamil-stimulated P-glycoprotein ATPase activity was inhibited by glycyrrhetinic acid. Glycyrrhetinic acid stimulated the ATPase activity of MRP1. CONCLUSION: These results suggest that dietary phytochemicals, such as glycyrrhetinic acid found in licorice, have dual inhibitory effects on P-glycoprotein and MRP1 and might become useful to enhance the efficacy of cancer chemotherapy.