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1.
Purpose  Naringenin has shown paradoxical results to modulate the function of multidrug resistance-associated proteins (MRPs). The aim of this study is to interpret whether naringenin can reverse intrinsic and/or acquired resistance of cancer cells to chemotherapeutic agents. Methods  The effects of naringenin on the uptake, retention and cytotoxicity of doxorubicin were investigated in A549, MCF-7, HepG2 and MCF-7/DOX cells. Cellular efflux pathways modulated by naringenin were assessed with their specific substrates and inhibitors. The improved antitumor activity of doxorubicin in combination with naringenin was also investigated in vivo. Results  The IC50 values of doxorubicin in combination with naringenin in A549 and MCF-7 cells were approximately 2-fold lower than that of doxorubicin alone. The increased sensitivity to doxorubicin by naringenin in HepG2 and MCF-7/DOX cells was not observed. Naringenin increased the cellular doxorubicin accumulation through inhibiting doxorubicin efflux in the cells expressing MRPs but not P-gp. In contrast to doxorubicin alone, doxorubicin in combination with naringenin enhanced antitumor activity in vivo with low systemic toxicity. Conclusion  Naringenin enhances antitumor effect of doxorubicin by selective modulating drug efflux pathways. Naringenin will be a useful adjunct to improve the effectiveness of chemotherapeutic agents in treatment of human cancers.  相似文献   

2.
目的探讨三氧化二砷(As2O3)对人肺腺癌A549/R细胞耐药性的逆转作用及对多药耐药相关蛋白(MRP)表达的影响。方法以荧光分光光度计测定细胞内药物浓度的改变,采用半定量逆转录聚合酶联反应(RT PCR) 技术检测As2O3处理后A549/R MRP基因表达的变化。结果As2O3的非细胞毒性剂量可增加A549/R细胞内多柔比星(ADM)浓度,降低其IC50。A549/R细胞中MRP呈过表达状态,不同浓度的As2O3处理A549/R后MRP表达水平明显降低。结论As2O3可部分逆转A549/R细胞对ADM的耐药性,其逆转机制与改变MRP基因表达有关。  相似文献   

3.
目的研究GP与抗癌药物合用对肿瘤多药耐药的逆转。方法MTT法测定GP与抗癌药物合用对K562/DOX和A549/DOX细胞的细胞毒作用;流式细胞术测定GP对K562/DOX细胞内阿霉素累积的影响。结果GP与阿霉素合用,能够明显逆转K562/DOX细胞对阿霉素的耐药性,并且能够浓度依赖性增加K562/DOX细胞内阿霉素的剂量;GP与阿霉素、顺铂、长春新碱合用时,对A549/DOX耐药性逆转作用相对较弱。结论GP能促进抗癌药物在MDR细胞内的累积,增强抗癌药物对MDR细胞的细胞毒作用,逆转肿瘤多药耐药。  相似文献   

4.
The failure of the clinical treatment of cancer patients is often attributed to drug resistance of the tumor to chemotherapeutic agents. P-glycoprotein (P-gp) contributes to drug resistance via adenosine 5'-triphosphate (ATP)-dependent drug efflux pumps and is widely expressed in many human cancers. Up to date, a few of nanomaterials have shown the effects on P-gp function by different ways. To study the mechanism of the increased cytotoxicity of doxorubicin (DOX) by pegylated phosphotidylethanolamine (PEG-PE) in drug-resistant cancer cells, a series of in vitro cell assays were performed, including identification of P-gp function, quantitative studies on uptake and efflux of DOX, inhibitory effects of blank PEG-PE micelles on mRNA and protein levels of P-gp, and intracellular ATP content alteration. Finally, combining MDR-1 RNA interference (siRNA) with DOX encapsulated in PEG-PE micelles (M-DOX) to improve cytotoxicity of DOX was also studied. M-DOX showed fivefold lower the concentration that caused 50% killing tumor cell than that of free DOX in the P-gp-overexpressing MCF-7 breast cancer (MCF-7/ADR) cells. M-DOX enhanced the cellular uptake and retention of DOX in MCF-7/ADR cells. PEG-PE block molecules can inhibit P-gp expression through downregulating MDR-1 gene. Cytotoxicity of M-DOX was further improved by knocking down the MDR-1 gene using siRNA in the multidrug-resistant cells. We conclude that the increased cytotoxicity of DOX encapsulated in PEG-PE micelle is due to the reduced P-gp expression by PEG-PE block molecules, and accordingly enhancing the cellular accumulation of DOX. To overcome drug resistance of tumor cells, the combination of nanotechnology and biotechnology could be an effective strategy such as PEG-PE formed micelles and siRNA.  相似文献   

5.
Drug resistance, one of the major obstacle in the successful anticancer therapy, can be observed at the outset of therapy (intrinsic resistance) or after exposure to the antitumor agent (acquired resistance). To gain a better insight into the mechanisms of intrinsic resistance we have analyzed two human cell types derived from untreated tumors: MCF-7 breast cancer and A549 non small cell lung cancer (NSCLC). We have examined: the cytotoxic effect induced by doxorubicin (DOX); the time course of drug accumulation by flow cytometry and intracellular drug distribution by confocal microscopy; the expression and distribution of proteins related to anthracycline resistance, such as P-gp (P-glycoprotein), MRP1 (multidrug resistance-associated protein) and LRP (lung resistance-related protein). The cytotoxicity assays showed that A549 cells were less sensitive than MCF-7 cells to the DOX treatment in agreement with the different DOX uptake. Moreover, while in A549 cells DOX was mostly located in well defined intracytoplasmic vesicles, in MCF-7 cells it was mainly revealed inside the nuclei. The analysis of P-gp and MRP expression did not show significant differences between the two cell lines while a high expression of LRP was detected at the nuclear envelope and cytoplasmic levels in A549 cells. These findings suggest that the lower sensitivity to DOX treatment showed by lung carcinoma cells could be ascribed to drug sequestration by LRP inside the cytoplasmic compartments.  相似文献   

6.
The transmembrane transport of drug loaded micelles to intracellular compartment is quite crucial for efficient drug delivery. In the current study, we investigated the cellular internalization and anticancer activity of doxorubicin loaded micelles with folate modified stealthy PEOz corona. Folate-decorated micelles incorporating doxorubicin were characterized for particle size, degree of folate decoration, drug loading content and encapsulation efficiency, morphology, and surface charge. The targeting capability and cell viability were assessed using HeLa, KB, A549 and MCF-7/ADR cell lines. In vitro study clearly illustrated the folate receptor (FR) mediated targeting of FA modified micelles to FR-positive human HeLa, KB and MCF-7/ADR cells, while specific delivery to FR-negative A549 cells was not apparently increased at the same experimental conditions. Cytotoxicity assay showed 60% and 58% decrease in IC50 values for HeLa and KB cells, while only a slight decrease for A549 cells, following treatment with folate modified formulations. The enhanced intracellular delivery of FA modified micelles in MCF-7/ADR cells was also observed. In vivo antitumor tests revealed DOX entrapped FA-PEOz-PCL micelles effectively inhibited the tumor growth and reduced the toxicity to mice compared with free DOX. The current study showed that the targeted nano-vector improved cytotoxicity of DOX and suggested that this novel PEOz endowed stealthy micelle system held great promise in tumor targeted therapy.  相似文献   

7.
吴金枝  谢曜爵  李宁 《贵州医药》2013,(11):967-970
目的研究多种细胞因子诱导的杀伤细胞(CIK)对A549/DDP肺癌耐药细胞株的抗增殖和诱导凋亡作用。方法应用细胞计数法设计细胞浓度,通过相差显微镜下观察CIK细胞对A549/DDP肺癌耐药细胞株形态学影响。结果随着CIK细胞与肺癌细胞效靶比增加及作用时间延长,抑制率明显增强,CIK细胞作用于肺癌细胞24h后,形态学观察肺癌细胞发生凋亡或坏死。结论体外制备的CIK细胞对肺癌耐药细胞株A549/DDP具有抑制增殖和促进凋亡作用。  相似文献   

8.
王天晓  杨晓虹 《药学学报》2008,43(5):461-466
本文探讨了异汉防己碱对P-糖蛋白(P-gp)介导的人乳腺癌细胞多药耐药性的逆转作用。首先以RT-PCR和免疫组化方法分别从RNA和蛋白水平检测MCF-7/DOX细胞P-gp表达情况,以明确MCF-7/DOX细胞的耐药特征;然后采用MTT法检测异汉防己碱的内在细胞毒性及其对阿霉素(DOX)的增敏作用,并以RF(reversal fold)值评价其逆转效果;同时应用流式细胞仪(FCM)对细胞内DOX的蓄积量进行了分析;再以免疫组化方法检测异汉防己碱对MCF-7/DOX细胞P-gp表达水平的影响;最后采用罗丹明蓄积和外排试验检测了异汉防己碱对P-gp功能的影响。整个试验以维拉帕米作为阳性对照。实验结果表明:MCF-7/DOX细胞是具有多药耐药表型且P-gp表达阳性的细胞株;无毒剂量异汉防己碱可明显增强DOX对MCF-7/DOX细胞的细胞毒性(RF=3.89),明显高于维拉帕米(RF=2.54)的逆转活性(P<0.05),但其几乎不影响DOX对MCF-7细胞的抑制作用;异汉防己碱对MCF-7/DOX细胞P-gp表达水平无明显影响,但其可有效抑制P-gp的药物外排功能。因此,异汉防己碱可有效逆转P-gp介导的人乳腺癌细胞的多药耐药性,它可能成为有效多药耐药逆转剂的候选药物。  相似文献   

9.
目的探讨非离子表面活性剂聚氧乙烯醚﹑聚乙二醇300﹑曲拉通X100对肺癌耐药细胞A549/DDP(耐顺铂)多药耐药性的逆转及其机制。方法用四氮唑盐(MTT)法进行体外耐药逆转实验,Westernblot检测P-gp(P-糖蛋白)蛋白的表达。结果①合用非离子型表活剂前后,A549/DDP对化疗药物阿霉素、顺铂、丝裂霉素、5-氟尿嘧啶、依托泊甙和长春新碱的敏感性显著增加(各组都为P<0.01);②三种非离子型表面活性剂能抑制P-gp蛋白的表达。结论三种非离子表面活性剂具有逆转A549/DDP耐药性的作用,逆转机制与其抑制P-gp蛋白的表达有关。  相似文献   

10.
《药学学报(英文版)》2020,10(6):1036-1046
MiR-142-3p has been reported to act as a tumor suppressor in breast cancer. However, the regulatory effect of miR-142-3p on drug resistance of breast cancer cells and its underlying mechanism remain unknown. Here, we found that miR-142-3p was significantly downregulated in the doxorubicin (DOX)-resistant MCF-7 cell line (MCF-7/DOX). MiR-142-3p overexpression increased DOX sensitivity and enhanced DOX-induced apoptosis in breast cancer cells. High-mobility group box 1 (HMGB1) is a direct functional target of miR-142-3p in breast cancer cells and miR-142-3p negatively regulated HMGB1 expression. Moreover, overexpression of HMGB1 dramatically reversed the promotion of apoptosis and inhibition of autophagy mediated by miR-142-3p up-regulation. In conclusion, miR-142-3p overexpression may inhibit autophagy and promote the drug sensitivity of breast cancer cells to DOX by targeting HMGB1. The miR-142-3p/HMGB1 axis might be a novel target to regulate the drug resistance of breast cancer patients.  相似文献   

11.
To overcome multi-drug resistance (MDR) of cancer cells, paclitaxel (PTX) and doxorubicin (DOX)-loaded nanostructured lipid carriers (NLC) were prepared by solvent diffusion method using monostearin as solid lipid and oleic acid as liquid lipid matrix. The cytotoxicities and reversal activity of drug-loaded NLC were tested against human breast cancer (MCF-7) cells, human ovarian cancer (SKOV3) cells and their multi-drug resistant (MCF-7/ADR and SKOV3-TR30) cells. The chemical conjugant of folic acid and stearic acid (FA-SA) was further synthesized to prepare folated NLC. Comparing with taxol and doxorubicin solution, the NLC loading PTX exhibited high cytotoxicities in MCF-7 and MCF-7/ADR cells, while the NLC loading DOX only indicated high cytotoxicity in MCF-7/ADR cells. The reversal powers of the NLC loading PTX and DOX were 34.3 and 6.4 folds, respectively. The NLC loading PTX and DOX showed the same trends of enhanced cytotoxicity against SKOV3 and SKOV3-TR30 cells. The reversal powers were 31.3 and 2.2 folds for the NLC loading PTX and DOX, respectively. The modification of NLC with FA-SA could further enhance the cytotoxicities of drug in drug sensitive and drug resistant cells.  相似文献   

12.
薏苡仁提取物注射液对人肺腺癌的抗肿瘤作用研究   总被引:2,自引:0,他引:2  
目的研究薏苡仁提取物注射液(康莱特,Kanglaite)对人肺腺癌体外及体内的抗肿瘤作用。方法运用CCK-8细胞增殖试验、划痕试验以及Transwell小室穿膜试验考察康莱特对A549细胞株的增殖、迁移及侵袭的影响;建立人肺腺癌A549裸鼠异种移植模型,考察高、中和低剂量静脉给药的康莱特单用或与顺铂合用的抗肿瘤作用。结果体外试验显示,经康莱特作用后,A549细胞的增殖、迁移和侵袭均受到明显抑制。康莱特高、中和低剂量静脉给药,对人肺腺癌A549裸鼠异种移植模型的肿瘤相对增殖率分别为34.52%、36.67%和42.47%;高、中和低剂量康莱特合并低剂量顺铂的肿瘤相对增殖率分别为26.75%、22.48%及29.82%。结论康莱特在体外及体内对人肺腺癌均有良好的抗肿瘤活性。康莱特与低剂量顺铂合用,体内抗肿瘤作用增强。  相似文献   

13.
目的探讨注射用黄芪多糖药物血清在体外对耐顺铂(DDP)人肺腺癌A549/DDP细胞株的耐药逆转作用。方法通过建立小鼠肿瘤模型,运用血清药理学方法,以人肺腺癌敏感细胞A549和耐药细胞A549/DDP为研究对象,采用细胞毒实验(MTT)方法,探讨注射用黄芪多糖对耐顺铂人肺腺癌细胞A549/DDP的耐药逆转作用。结果注射用黄芪多糖药物血清高、中、低剂量组分别与DDP合用时对A549/DDP细胞的耐药逆转倍数分别为1.24、1.41、1.34;且中、高剂量组与阳性对照DDP组比较差异有统计学意义(P〈0.05)。结论注射用黄芪多糖能明显增加A549/DDP耐药细胞对DDP的敏感性,提高细胞死亡率,具有耐药逆转作用。  相似文献   

14.
1.?The expression and function of P-glycoprotein (P-gp) is associated with the phenotype of multidrug resistance (MDR). Saikosaponin A (SSA) is a triterpenoid saponin isolated from Radix Bupleuri. This study was mainly designed to understand effects of SSA on MDR in MCF-7/ADR and HepG2/ADM cells.

2.?MDR reversal was examined as the alteration of cytotoxic drugs IC50 in resistant cells in the presence of SSA by MTT assay, and was compared with the non-resistant cells. Apoptosis and uptake of P-gp substrates in the tumor cells were detected by flow cytometry. Western blot was performed to assay the expression of P-gp.

3.?Our results demonstrate SSA could increase the chemosensitivity of P-gp overexpressing HepG2/ADM and MCF-7/ADR cells to doxorubicin (DOX), vincristine (VCR) and paclitaxel. SSA promoted apoptosis of MCF-7/ADR cells in the presence of DOX. Moreover, it could also increase the retention of P-gp substrates DOX and rhodamine 123 in MCF-7/ADR cells, and decrease digoxin efflux ratio in Caco-2 cell monolayer. Finally, a mechanistic study showed that SSA reduced P-gp expression without affecting hydrolytic activity of P-gp.

4.?In conclusion, our findings suggest that SSA could be further developed for sensitizing resistant cancer cells and used as an adjuvant therapy together with anticancer drugs to improve their therapeutic efficacies.  相似文献   

15.
目的 探讨注射用黄芪多糖药物血清在体外对耐顺铂(DDP)人肺腺癌A549/DDP细胞株的耐药逆转作用。方法 通过建立小鼠肿瘤模型,运用血清药理学方法,以人肺腺癌敏感细胞A549和耐药细胞A549/DDP为研究对象,采用细胞毒实验(MTT)方法,探讨注射用黄芪多糖对耐顺铂人肺腺癌细胞A549/DDP的耐药逆转作用。结果 注射用黄芪多糖药物血清高、中、低剂量组分别与DDP合用时对A549/DDP细胞的耐药逆转倍数分别为1.24、1.41、1.34;且中、高剂量组与阳性对照DDP组比较差异有统计学意义(P<0.05)。结论 注射用黄芪多糖能明显增加A549/DDP耐药细胞对DDP的敏感性,提高细胞死亡率,具有耐药逆转作用。  相似文献   

16.
Cyclophosphamide (CPA) is a widely used chemotherapeutic drug in neoplasias. It is a DNA and protein alkylating agent that has a broad spectrum of activity against variety of neoplasms including breast cancer. The therapeutic effectiveness of CPA is limited by the high-dose hematopoietic, renal, and cardiac toxicity that accompanies the systemic distribution of liver-derived activated drug metabolites. The present study examines the potential of combining well-tolerated antibiotic doxycycline (DOX) with CPA and understanding the mechanism of cell killing. Interestingly, we found that DOX significantly enhances the tumor regression activity of CPA on xenograft mice model bearing MCF-7 cells. DOX also potentiates MCF-7 cell killing by CPA in vitro. In presence of DOX (3 microg/ml), the IC50 value of CPA decreased significantly from 10 to 2.5 mM. Additional analyses indicate that the tumor suppressor p53 and p53-regulated proapoptotic Bax were upregulated in vivo and in vitro following CPA treatment in combination with DOX, suggesting that upregulation of p53 may contribute to the enhancement of antitumor effect of CPA by DOX. Furthermore, downregulation of antiapoptotic Bcl-2 was observed in animals treated with CPA and CPA plus DOX when compared to untreated or DOX-treated groups. Our results raise the possibility that this combination chemotherapeutic regimen may lead to additional improvements in treatment of breast cancer.  相似文献   

17.
In this study, reduction-sensitive self-assembled polymer nanoparticles based on poly (lactic-co-glycolic acid) (PLGA) and chondroitin sulfate A (CSA) were developed and characterized. PLGA was conjugated with CSA via a disulfide linkage (PLGA-ss-CSA). The critical micelle concentration (CMC) of PLGA-ss-CSA conjugate is 3.5?µg/mL. The anticancer drug doxorubicin (DOX) was chosen as a model drug, and was effectively encapsulated into the nanoparticles (PLGA-ss-CSA/DOX) with high loading efficiency of 15.1%. The cumulative release of DOX from reduction-sensitive nanoparticles was only 34.8% over 96?h in phosphate buffered saline (PBS, pH 7.4). However, in the presence of 20?mM glutathione-containing PBS environment, DOX release was notably accelerated and almost complete from the reduction-sensitive nanoparticles up to 96?h. Moreover, efficient intracellular DOX release of PLGA-ss-CSA/DOX nanoparticles was confirmed by CLSM assay in A549 cells. In vitro cytotoxicity study showed that the half inhibitory concentrations of PLGA-ss-CSA/DOX nanoparticles and free DOX against A549 cells were 1.141 and 1.825?µg/mL, respectively. Therefore, PLGA-ss-CSA/DOX nanoparticles enhanced the cytotoxicity of DOX in vitro. These results suggested that PLGA-ss-CSA nanoparticles could be a promising carrier for drug delivery.  相似文献   

18.
One of the proposed mechanisms for multidrug resistance relies on the ability of resistant tumor cells to efficiently promote glutathione S-transferase (GST)-catalyzed GSH conjugation of the antitumor drug. This type of conjugation, observed in several families of drugs, has never been documented satisfactorily for anthracyclines. Adriamycin-resistant human breast cancer MCF-7/DOX cells, presenting a comparable GSH concentration, but a 14-fold increase of the GST P1–1 activity relative to the sensitive MCF-7 cells, have been treated with adriamycin in the presence of verapamil, an inhibitor of the 170 P-glycoprotein (P-gp) drug transport protein, and scrutinized for any production of GSH–adriamycin conjugates. HPLC analysis of cell content and culture broths have shown unequivocally that no GSH conjugates are present either inside the cell or in the culture broth. The only anthracycline present inside the cells after 24 hr of incubation was > 98% pure adriamycin. Confocal laser scanning microscopic observation showed that in MCF-7/DOX cells adriamycin was localized mostly in the Golgi apparatus rather than in the nucleus, the preferred site of accumulation for sensitive MCF-7 cells. These findings rule out GSH conjugation or any other significant biochemical transformation as the basis for resistance to adriamycin and as a ground for the anomalous localization of the drug in the cell. Adriamycin, daunomycin, and menogaril did not undergo meaningful conjugation to GSH in the presence of GST P1–1 at pH 7.2. Indeed, their synthetic C(7)-aglycon–GSH conjugates exerted a strong inhibitory effect on GST P1–1, with Ki at 25° in the 1–2 μM range, scarcely dependent on their stereochemistry at C(7).  相似文献   

19.
目的探讨人参皂苷Rh2(S型与R型)能够诱导人肺腺癌A549细胞凋亡。方法采用MTT实验测定细胞增殖能力;台肦蓝染色法检测细胞存活率;碘化丙啶(PI)单染流式细胞仪分析细胞周期中各时期的细胞百分数;电镜观察细胞凋亡。结果 30μg/mL的S型和R型人参皂苷Rh2作用于A549细胞48h后,死亡率均明显高于正常组细胞(P<0.05);20(S)-Rh2能阻滞细胞周期于G1期,并且2(S)-Rh2型的抗肿瘤活性明显强于20(R)-Rh2;电镜结果显示染色质浓集、断裂,核固缩并出现凋亡小体。结论 S型和R型人参皂苷Rh2均具有促进A549细胞凋亡的生物学功能。  相似文献   

20.
目的化疗耐药是乳腺癌复发转移、治疗效果不理想的主要因素。本文探讨miR-142-3p通过靶向高迁移率族蛋白1(high-mobility group box 1,HMGB1)提高乳腺癌化疗敏感性的分子机制。方法实时荧光定量PCR检测人乳腺癌MCF-7细胞及阿霉素耐药株MCF-7/DOX细胞中的miR-142-3p水平;MTT法检测阿霉素(doxorubicin,DOX)处理后各组的增殖情况、流式细胞术检测凋亡率、Western blot检测HMGB1和自噬有关蛋白的表达水平;双荧光素酶报告实验评价miR-142-3p对HMGB1的靶向调控作用。结果阿霉素耐药株MCF-7/DOX细胞中的miR-142-3p水平明显下调。miR142-3p的过度表达增强了乳腺癌细胞对阿霉素的敏感性和提高阿霉素诱导的凋亡比率。HMGB1是乳腺癌细胞中miR-142-3p的直接功能靶点,HMGB1的过表达可以明显解除由miR-142-3p上调所产生的细胞凋亡和自噬抑制。结论miR-142-3p的过表达可能通过抑制自噬靶向HMGB1,增强乳腺癌细胞对阿霉素的化学敏感性。miR-142-3p/HMGB1为提高乳腺癌对药物的敏感性提供了新的靶点,具有一定价值。  相似文献   

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