川芎嗪脂质体对人白血病细胞株K562多药耐药逆转作用的研究

目的:研究川芎嗪脂质体在体外对肿瘤细胞的细胞毒作用和对多药耐药的逆转作用,并研究脂质体剂型对上述作用的影响.方法:MTT法检测川芎嗪脂质体以及川芎嗪原料对照组、空白脂质体对照组对耐阿霉素的人白血病细胞株(K562/ADM)的细胞毒性和多药耐药逆转作用.结果:川芎嗪脂质体对K562/ADM有明显的细胞毒作用.非细胞毒性剂量(生长率≥95%)为2.0μg·ml-1,该浓度下可显著降低ADM对K562/ADM细胞的IC50(P＜0.01),抗药性逆转为11.2倍.低毒剂量(生长率85～90%)为2.6μg·ml-1,抗药性逆转为178倍.2.0μg·ml-1的川芎嗪原料对照组可显著降低ADM对K562/ADM细胞的IC50(P＜0.01),抗药性逆转为7.9倍;同比稀释的空白脂质体对照组可显著降低ADM对K562/ADM细胞的IC50(P＜0.01),抗药性逆转为4.9倍.结论:川芎嗪脂质体体外对人白血病细胞K562/ADM有明显的细胞毒作用和MDR逆转作用;在一定浓度范围内川芎嗪脂质体的细胞毒性与逆转作用有剂量依赖性;脂质体本身对逆转有增效作用.     

米非司酮联合三氧化二砷对K562/ADM的逆转作用及其机制

目的:探讨米非司酮(mifepristone)联合三氧化二砷(As2O3)对K562/ADM的逆转作用及机制研究。方法:不同浓度米非司酮、As2O3处理细胞72h,采用MTT法检测细胞增殖活性;流式细胞仪检测细胞凋亡、分光光度法检测细胞谷胱甘肽(GSH)含量。结果:10μmol.L-1的米非司酮对K562/ADM细胞无明显杀伤,可有效逆转K562/ADM细胞耐药性,此浓度米非司酮联合As2O3(2.0μmol.L-1)作用于K562/ADM细胞后,逆转倍数明显增高(P<0.01),GSH含量明显低于同浓度单用药组(P<0.05)。对细胞增殖抑制及其诱导凋亡的效果均明显高于同浓度单用药组(P<0.05)。结论:米非司酮联合As2O3逆转作用增强,机制可能与凋亡加强及GSH含量改变有关。     

苦瓜蛋白逆转K562／AO2细胞多药耐药性的研究

目的：研究非细胞毒性质量浓度苦瓜蛋白对耐阿霉素的人红白血病细胞株K562／AO2多药耐药性的逆转作用和促凋亡作用。方法：采用CCK-8法测定苦瓜蛋白的细胞毒性及其对K562／AO2细胞敏感性的影响,用流式细胞仪检测K562／AO2细胞经不同药物处理后细胞的凋亡情况。结果：苦瓜蛋白对K562／AO2细胞有一定的细胞毒作用,其非细胞毒性质量浓度为5μg／mL,非细胞毒性质量浓度苦瓜蛋白对K562／AO2细胞对阿霉素、长春新碱（VCR）和柔红霉素的耐药性都有部分逆转作用（分别为5．4、6．5和4．0倍）;5μg／mL苦瓜蛋白联合VCR诱导K562／AO2细胞凋亡,凋亡率为（19．38±1．06）％,而对照组为（1．64±0．27）％,单一苦瓜蛋白组为（3．79±0．82）％,单一VCR组为（9．83±0．98）％。结论：苦瓜蛋白能部分逆转人红白血病K562／AO2细胞对阿霉素、VCR和柔红霉素的耐药,一定剂量的苦瓜蛋白与VCR联合应用可增加肿瘤细胞凋亡率。     

木犀草素对白血病K562/ADR细胞多药耐药的逆转作用及机制研究

目的 探究木犀草素（Lut）对慢性髓系白血病K562/ADR细胞多药耐药性的逆转作用及其机制。方法K562和K562/ADR细胞经不同浓度阿霉素（ADR）处理24 h后，采用CCK-8实验检测K562/ADR细胞耐药倍数。Lut单独或联合ADR作用K562/ADR细胞24 h后，采用CCK-8实验检测Lut的细胞毒性及对ADR的增敏作用。取对数生长期K562/ADR细胞分为0μmol/L Lut组、2μmol/L Lut组、4μmol/L Lut组，采用流式细胞术检测细胞内ADR蓄积量的变化；RT-PCR法和Western blot法分别检测核因子E2相关因子2(Nrf2)、多药耐药相关蛋白1(MRP1)、P-糖蛋白（P-gp）、谷胱甘肽-S-转移酶pi(GST-pi)mRNA和蛋白的表达；谷胱甘肽（GSH）试剂盒检测细胞内GSH的含量。结果 与K562细胞相比，K562/ADR细胞株对ADR具有明显的耐药性，耐药倍数为53.69倍。与0μmol/L Lut相比，不同浓度Lut作用于K562/ADR细胞后，细胞生长均受到不同程度的抑制（P<0.05），其中2、4μmol/L Lu...     

4-[4″-(2″,2″,6″,6″-四甲基-1″-哌啶氮氧自由基)氨基]-4′-去甲表鬼臼毒素对K562/ADM细胞的抑制作用

目的比较4-[4″-(2″,2″,6″,6″-四甲基-1″-哌啶氮氧自由基)氨基]-4′-去甲表鬼臼毒素(GP-7)对多药耐药人慢性粒细胞白血病K562的多柔比星耐药株细胞(K562/ADM细胞)的抑制作用是否优于依托泊苷。方法以依托泊苷和K562细胞为对照,用不同浓度GP-7处理K562/ADM细胞不同时间,MTT比色法测定细胞增殖,流式细胞仪测定细胞周期和细胞凋亡率,普通光学显微镜观察细胞凋亡形态,琼脂糖凝胶电泳观察细胞DNA凋亡性降解。结果8~128mol.L-1GP-7处理48h或64μmol.L-1GP-7处理24~72h,GP-7对K562/ADM细胞的增殖抑制呈剂量依赖性(r=0.947,P<0.05)和时间依赖性(r=0.999,P<0.01)。GP-7及依托泊苷对K562/ADM的IC50分别为(45.9±1.8)及(68.7±4.6)μmol.L-1;64μmol.L-1GP-7作用48h可使G2/M期细胞明显增多,相同情况下依托泊苷则使S期细胞明显增多;GP-7可引起K562/ADM和K562细胞凋亡,但其引起的K562/ADM和K562细胞凋亡率与依托泊苷无明显差异;GP-7可引起K562/ADM和K562细胞典型的凋亡形态学变化和DNA凋亡性降解,但GP-7引起的K562/ADM细胞DNA凋亡性降解弱于K562细胞;128及256μmol.L-1GP-7或依托泊苷处理K562/ADM和K562细胞48h,GP-7诱导DNA凋亡性降解的作用强于依托泊苷,但32和64μmol.L-1时作用则相反。结论GP-7可抑制多药耐药白血病细胞株K562/ADM的增殖,诱导细胞凋亡。GP-7抑制多药耐药白血病细胞株K562/ADM的作用优于依托泊苷。     

自噬水平与白血病K562/ADM细胞耐药的关系研究

目的采用阿霉素(adriamycin,ADM)“逐步提高药物浓度+间歇性诱导”的方式体外诱导建立稳定耐受15μmol·L^-1 ADM的白血病K562/ADM细胞,观察该细胞对其它化疗药物的敏感性以及细胞自噬水平与耐药的关系。方法MTT法检测细胞对几种化疗药物的敏感性;用透射电镜、荧光显微镜观察细胞自噬形态学改变;Annexin-V/PI双染流式细胞仪检测细胞凋亡;Western blot检测自噬和耐药相关蛋白的表达水平。结果K562/ADM细胞除了对ADM产生明显耐药外,还对多种化疗药物如:吡柔比星、柔红霉素、5-FU和长春新碱等有交叉耐药,但对三氧化二砷较敏感。K562/ADM细胞内自噬体数量、MDC荧光强度以及LC3Ⅰ/Ⅱ、Beclin-1蛋白表达水平均高于亲本细胞。用3-MA抑制自噬可明显增加K562/ADM细胞对ADM的敏感性,同时也能有效抑制K562/ADM细胞内耐药相关蛋白的表达。结论K562/ADM细胞出现多药耐药现象,且耐药性与细胞自噬水平有密切关系。     

桑皮苷A逆转K562/阿霉素耐药细胞化疗多药耐药的研究

目的 研究桑皮苷A对人白血病耐药细胞K562/阿霉素耐药细胞（K562/ADM）化疗耐药的影响。方法 实验分为溶媒（DMSO）对照组、阳性对照组(10μmol·L^-1维拉帕米处理48 h,再用5μg·mL^-1阿霉素孵育1 h或2μg·mL^-1罗丹明123孵育1.5 h)、阿霉素单用组(5μg·mL^-1阿霉素孵育1 h)、阿霉素合用桑皮苷A组(用5,10,20μmol·L^-1桑皮苷A处理48 h,再用5μg·mL^-1阿霉素孵育1 h)、罗丹明123合用桑皮苷A组(用5,10,20μmol·L^-1桑皮苷A处理48 h,再用2μg·mL^-1罗丹明123孵育1.5 h)。用噻唑蓝（MTT）实验初步确定桑皮苷A的逆转耐药作用;再以细胞内阿霉素蓄积实验,罗丹明123（Rho123）蓄积及外排实验进一步研究桑皮苷A的逆转耐药作用;分别用聚合酶链反应（PCR）和蛋白质印迹（Western blot）法检测桑皮苷A对K562/AD...     

α-干扰素增强耐药性白血病K562/ADM细胞及其白血病干细胞对阿霉素的敏感性

目的研究α-干扰素(interferon alpha,IFN-α)对白血病多药耐药K562/ADM群体细胞及其白血病干细胞(LSC)对细胞周期特异性药物阿霉素敏感性的影响。方法以K562/ADM耐药细胞为靶细胞,采用噻唑蓝(MTT)比色法检测细胞增殖活性;流式细胞术碘化丙啶(PI)染色和AnnexinV/PI双染色分别测定细胞周期分布和细胞凋亡;抗CD34、CD38和CD123抗体以及Annexin V共染色检测群体细胞中LSC的含量及凋亡率。结果 IFN-α作用后K562/ADM细胞周期分布发生改变,G0/G1期细胞比例减少,S期细胞比例增高。IFN-α与阿霉素联合作用,明显增强阿霉素对K562/ADM细胞的增殖抑制作用,细胞凋亡率增高。IFN-α可提高K562/ADM细胞群体中LSC的含量(比例),且增加LSC对阿霉素的敏感性,凋亡的LSC数量增高。结论 IFN-α促进K562/ADM群体细胞及其LSC进入细胞增殖周期而提高对细胞周期特异性抗癌药物阿霉素的敏感性。     

洛美利嗪衍生物CJZ3对K562/DOX细胞阿霉素耐药的逆转作用

目的研究洛美利嗪衍生物CJZ3对K562/DOX细胞阿霉素耐药的逆转作用。方法应用流式细胞仪和MTT法观察了CJZ3对K562/DOX细胞P-糖蛋白(P-glycoprotein,P-gp)的抑制作用及对K562/DOX细胞阿霉素耐药的逆转作用。结果CJZ3能剂量相关性地增加K562/DOX细胞对罗丹明123(rhodamine123,Rh123)的摄取以及细胞内罗丹明Rh123的累计,明显抑制P-gp介导的Rh123外排,增强阿霉素对K562/DOX细胞的细胞毒作用,提高阿霉素诱导的K562/DOX细胞凋亡率,提高细胞Caspase-3活性,增加K562/DOX细胞内阿霉素水平。结论洛美利嗪衍生物CJZ3体外能明显抑制P-gp的外排功能,逆转P-gp介导的K562/DOX细胞的多药耐药性。     

木香烃内酯对K562/A02细胞阿霉素耐药的逆转作用研究

目的探索木香烃内酯对白血病耐药细胞系K562/A02阿霉素耐药的逆转作用。方法将木香烃内酯与K562/A02细胞共培养72 h后,采用MTT法检测木香烃内酯对细胞生长的抑制作用。不同浓度木香烃内酯处理K562/A02细胞24 h后,采用Annexin V和PI双染法检测木香烃内酯对细胞的凋亡。不同浓度木香烃内酯与阿霉素共培养72 h后采用MTT法检测木香烃内酯对K562/A02细胞的耐药逆转情况。采用流式细胞仪检测木香烃内酯处理24 h之后K562/A02细胞阿霉素蓄积以及细胞膜表面P-糖蛋白(P-gp)的表达。结果木香烃内酯对K562/A02细胞的生长具有明显抑制作用,呈显著的剂量相关性。与对照组比较,2.5~50μmol/L木香烃内酯组K562/A02细胞存活率显著降低(P0.05、0.01、0.001)。随着木香烃内酯浓度的增加,凋亡细胞的比例明显增加。与对照组比较,不同浓度木香烃内酯组细胞凋亡比例显著升高(P0.05、0.01、0.001)。加入5μmol/L木香烃内酯后,使K562/A02细胞对阿霉素的敏感性提高12倍。木香烃内酯处理后K562/A02细胞内部阿霉素的蓄积明显增加,呈浓度相关性。与对照组比较,5、10μmol/L木香烃内酯组K562/A02细胞内部阿霉素的蓄积增加显著升高(P0.05)。细胞表面的P-gp的表达并无显著影响。结论木香烃内酯能够抑制K562/A02细胞增殖,诱导K562/A02细胞凋亡,增强阿霉素的化疗敏感性,逆转阿霉素耐药。     

Effect and mechanism of nociceptin/orphanin FQ reversing multi-drug resistance in K562/ADM cell

OBJECTIVE: To investigate the effect and mechanism of nociceptin/orphanin FQ (OFQ) reversing multi-drug resistance of K562/ADM cells in vitro. METHODS: MTT assay, Wright staining, flow cytometry, transmission electron microscope and gel electrophoresis were used to evaluate the effect and mechanism of OFQ in reversing multi-drug resistance of K562/ADM cells. RESULTS: OFQ could time-dependently reverse the ADM resistance of K562/ADM cell. After treatment with OFQ (1 x 10(-7) mol x L(-1)), K562/ADM cells were cultured for 24, 48 and 72 h. The reversal index (RI) was 1.33, 1.42 and 1.53, respectively. Furthermore, OFQ significantly increased the intracellular accumulation of ADM in K562/ADM cells and percentage apoptosis in K562/ADM cells. OFQ down-regulated the level of P-gp time-dependently, while the level of Fas and FasL were up-regulated. There were evidently significant differences compared with the control (P < 0.01). After treating K562/ADM cells with OFQ (1 x 10(-7) mol x L(-1)) and ADM (20 microg x ml(-1)) for 48 hours, the cells showed apoptotic nuclear fragmentation, which was characterized by the appearance of a DNA ladder pattern in genomic DNA gel electrophoresis. CONCLUSION: OFQ can reverse the ADM resistance of K562/ADM cells. The mechanism involves OFQ up-regulating the expression of Fas/FasL, down-regulating the level of P-gp, and decreasing the intracellular level of calcium in K562/ADM cells.     

胡椒碱对乳腺癌阿霉素耐药细胞株 MCF -7/ADM 细胞的逆转作用

目的：探讨胡椒碱对人乳腺癌阿霉素（ADM）耐药细胞株 MCF -7/ ADM 的逆转作用及其机制。方法采用 CCK -8法观察胡椒碱联合阿霉素（ADM）对乳腺癌耐药株 MCF -7/ ADM 细胞生长增殖的影响;应用免疫印迹技术（Western - blot）测定胡椒碱联合 ADM 对MCF -7/ ADM 细胞表面 P -糖蛋白（P - gp）表达的影响。结果60,80,100μmol / L 胡椒碱试验组细胞耐药逆转倍数分别为1.62,2.08,3.78倍,差异有统计学意义（ P ﹤0.05）。胡椒碱能显著抑制 MCF -7/ ADM 细胞膜 P - gp 蛋白的表达,其作用随浓度的增加而增强。结论胡椒碱与 ADM 共同作用于 MCF -7/ ADM 细胞,可使细胞对 ADM 的敏感性增强。胡椒碱具有部分逆转 MCF -7/ ADM 细胞耐药的作用,其逆转作用机制可能与通过下调 P - gp 的表达有关。     

Acquired multidrug resistance in human K562/ADM cells is associated with enhanced autophagy

Abstract

Autophagy, as a necessary process for survival in mammalian cells deprived of nutrients or growth factors, will be activated in many tumor cells while treated with chemotherapeutic drugs, but the role of autophagy in acquired multidrug resistance of human acute myelogenous leukemia to adriamycin-based chemotherapy remains to be clarified. Our aim was to address that question by surveying the autophagic activity in parental acute myelogenous leukemia cell line K562 and resistant sub cell line, K562/ADM, which were obtained by treating adriamycin with increasing concentrations. K562/ADM and K562 cells were exposed to PBS culture medium for 3 hours, then the stress-induced autophagy was measured. Real-time quantitative RT-PCR revealed the expression of LC3 mRNA was higher in K562/ADM than in K562 cells. LC3-II, as an autophagosomal marker, was more abundant in K562/ADM than in K562 cells measured by Western blotting. To determine the effect of 3-MA, a known specific inhibitor of autophagy, on overcoming acquired multidrug resistance induced by adriamycin, the MTT assay and flow cytometry were performed. We also found that 3-MA can enhance the growth inhibition and apoptotic effect of adriamycin in acquired resistant cells (K562/ADM). Collectively, our results provide evidence that the upregulation of autophagy plays a major role in multidrug resistance of K562/ADM cells induced by adriamycin.     

洛美利嗪逆转K562/ADM细胞多药耐药性

目的研究洛美利嗪(lomerizine,Lom)逆转K562/ADM细胞多药耐药性的作用及机制。方法MTT法检测细胞毒作用,流式细胞仪研究Lom对ADM和长春新碱(vincristine,VCR)的K562/ADM细胞凋亡诱导作用的影响及对罗丹明123(rhodamine 123,Rh123)外排和P-糖蛋白(P-glycoprotein,P-gp)表达的作用。结果Lom明显提高ADM对K562/ADM多药耐药细胞的细胞毒作用及ADM和VCR的凋亡诱导作用,3,10和30 μmol·L^-1 Lom使K562/ADM对ADM的IC₅₀值由79.03 μmol·L^-1分别降至28.14,8.16和3.16 μmol·L^-1。Lom增加胞内ADM的蓄积浓度并抑制Rh123外排;但作用72 h后对K562/ADM细胞P-gp表达无影响。结论Lom通过抑制P-gp的活性逆转K562/ADM细胞的多药耐药性。     

抗多药耐药基因肽核酸与反义寡脱氧核苷酸增强K562／ADM细胞的敏感性和促进凋亡

AIM: To investigate the reversal effect and apoptosis enhancement of peptide nucleic acid (PNA) and antisenseoligodeoxyribonucleotide (ASODN) targeted to multidrug resistance gene (mdrl) on human multidrug resistantleukemia K562/ADM cells. METHODS: A 15-mer PNA and the same sequence of ASODN, complementary to the5' end of the AUG initiator codon-containing region of mdrl messenger RNA (MDR1-PNA, MDR1-ASODN), weredesigned and synthesized. Proliferation and sensitivity to adriamycin of K562/ADM cells treated with MDRI-PNAand MDR1-ASODN were analyzed with a MTT colorimetric assay. Apoptotic morphologies, P-glycoprotein (P-gp)expression, intracellular adriamycin accumulation, and cell cycle were measured. RESULTS: MDRI-PNA 1 to 10μmol/L and MDR1-ASODN 2 to 20 μmol/L alone had no inhibitory effects on the proliferation of K562/ADM cells,but significantly inhibited the growth of K562/ADM cells cultured in adriamycin-containing medium. After treatment with MDRI-PNA and MDRI-ASODN, intracellular adriamycin accumulation in K562/ADM cells increasedgreatly and P-gp synthesis was strikingly reduced. The resistance to adriamycin of the drug-resistant cells waspartly reversed and the cells were induced to apoptosis by adriamycin. The reversal efficacy of MDR1-PNA was3.1-fold higher than that of the same sequence of MDR-ASODN, but neither MDRI-PNA nor MDRI-ASODNcould completely block the mdrllP-gp expression. CONCLUSION: Sequence-special PNA targeted to mdr1 genemore effectively than the same sequence of MDR1-ASODN inhibited the expression of P-glycoprotein to overcomethe drug-resistance.     

雷公藤内酯醇对DU145/ADM细胞阿霉素化疗敏感性及逆转耐药的影响

目的探讨雷公藤内酯醇（TP）对DU145/ADM细胞阿霉素敏感性及逆转耐药的影响。方法采用MTT法检测TP预处理DU145/ADM细胞对阿霉素敏感性的影响,采用RT-PCR和Western blot分别检测相关基因转录水平与蛋白水平的变化。结果不同浓度TP（20、40、80 ng mL^-1）预处理DU145/ADM细胞72 h后,均可使细胞对不同浓度阿霉素（10、20、30、40、50 ng mL-1）敏感性较TP预处理前明显增加,mdr1表达较TP预处理前明显下降,并呈剂量相关性。结论 TP通过下调mdr1表达增强DU145/ADM细胞对阿霉素的敏感性,其有可能成为一种耐药逆转剂。     

CXCL12/CXCR4 axis confers adriamycin resistance to human chronic myelogenous leukemia and oroxylin A improves the sensitivity of K562/ADM cells

This study was aimed at investigating the reversal effect of oroxylin A, a naturally bioactive monoflavonoid separated and purified from Scutellaria baicalensis Georgi, in human chronic myeloid leukemia (CML) and the underlying mechanisms. The results showed that CXCL12 could enhance the resistance of K562 cells to adriamycin (ADM) by increasing the expression of CXCR4, up-regulating the downstream PI3K/Akt pathway, and promoting translocation of NF-κB dimers into nucleus and subsequently decreasing the expression of apoptosis-related proteins in K562 cells. And we found that ADM resistance was partially reversed by CXCR4 siRNA transfection. Moreover, the sensitivity enhancement of oroxylin A was demonstrated by decreasing the expression of CXCR4 at both protein and mRNA levels, via PI3K/Akt/NF-κB pathway and triggering the apoptosis pathway in vitro. In addition, the in vivo study showed that oroxylin A increased apoptosis of leukemic cells with low systemic toxicity, and the mechanism was the same as in vitro study. In conclusion, all these results showed that oroxylin A improved the sensitivity of K562/ADM cells by increasing apoptosis in leukemic cells and decreasing the expression of CXCR4 and PI3K/Akt/NF-κB pathway, and probably served as a most promising agent for CML treatment.     

木犀草素抑制白血病耐药株K562/A02的GST-π表达

目的探讨木犀草素（luteolin）对白血病耐药株K562/A02细胞谷胱甘肽S转移酶π（GST-π）的影响。方法木犀草素30 mmol/L预处理K562/A02细胞第1、35、d后,MTT法测定阿霉素IC50,采用722分光光度计测定细胞内GSH含量及Western Blot法测定木犀草素处理后GST-π蛋白表达。结果木犀草素对K562/A02的耐药性具有明显的逆转作用,用木犀草素处理后,对阿霉素药物敏感性的相对逆转效率第1、3、5 d分别为10.7%4、2.7%和15.8%;木犀草素显著降低K562/A02细胞内GSH含量,GST-π蛋白的表达于用药后第1、35、d分别下降22%5、6%和34%。结论木犀草素具有较强的逆转K562/A02细胞多药耐药的作用,其逆转机制可能与降低细胞内GSH含量,下调K562/A02细胞GST-π蛋白的表达相关。     

延长洛美利嗪作用时间可增加K562/A02细胞对阿霉素的敏感性

目的：研究洛美利嗪在高浓度、长时间作用于肿瘤细胞时，对多药耐药的逆转作用。探讨洛美利嗪逆转肿瘤细胞多药耐药的机制。方法：将不同浓度的洛美利嗪与人红白血病细胞系K562及其耐药细胞系K562／A02（耐阿霉素）共孵育24、48或72小时，然后分别向细胞中加入阿霉素，采用MTT法检测细胞毒作用；以流式细胞术测定两种细胞系内罗丹明123的潴留以反映P-糖蛋白的外排功能；利用Fluo-3／AM检测细胞内游离钙离子浓度。结果：细胞与洛美利嗪预温孵后，阿霉素对K562／A02细胞的IC50值减小，细胞内Rh123潴留增多，细胞内游离钙离子浓度明显升高。结论：洛美利嗪高浓度，长时间作用于K562／A02细胞，可以抑制细胞上P-糖蛋白的功能活性，使细胞对化疗药的敏感性增强，其机制可能与升高细胞内钙离子有关。