Effect of Histone Deacetylase Inhibition on the Expression of Multidrug Resistance-associated Protein 2 in a Human Placental Trophoblast Cell Line

Background： Placental multidrug resistance-associated protein 2 （MRP2）, encoded by ABCC2 gene in human, plays a significant role in regulating drugs＇ transplacental transfer rates. Studies o11 placental MRP2 regulation could provide more therapeutic targets for individualized and safe pharmacotherapy during pregnancy. Currently, the roles of epigenetic mechanisms in regulating placental drug transporters are still unclear. This study aimed to investigate the effect of histone deacetylases （HDACs） inhibition on MRP2 expression in the placental trophoblast cell line and to explore whether HDAC 1/2/3 are preliminarily involved in this process. Methods： The human choriocarcinoma-derived trophoblast cell line （Bewo cells） was treated with the HDAC inhibitors-trichostatin A （TSA） at different concentration gradients of 0.5, 1.0, 3.0, and 5.0 μmol/L. Cells were harvested after 24 and 48 h treatment. Small interfering RNA （siRNA） specific for HDACI/HDAC2/HDAC3 or control siRNA was transfected into cells. Total HDAC activity was detected by colorimetric assay kits. HDAC 1/2/3/ABCC2 messenger RNA （mRNA） and protein expressions were determined by real-time quantitative polymerase chain reaction and Western-blot analysis, respectively. Immunofluorescence for MRP2 protein expression was visualized and assessed using an immunofluorescence microscopy and ImageJ software, respectively. Results： TSA could inhibit total HDAC activity and HDAC 1/2/3 expression in company with increase ofM RP2 expression in Bewo cells. Reduction of HDAC 1 protein level was noted after 24 h of TSA incubation at 1.0, 3.0, and 5.0 μmol/L （vs. vehicle group, all P 〈 0.001 ）, accompanied with dose-dependent induction of MRP2 expression （P = 0.045 for 1.0 μmol/L, P = 0.001 for 3.0 μmol/L, and P 〈 0.001 for 5.0 μmol/L）, whereas no significant diferences in MRP2 expression were noted after HDAC2/3 silencing. Fluorescent micrograph images of MRP2 protein were expressed on the cell membrane. The fluorescent intensities of MRP2 in the control, HDAC2, and HDAC3 siRNA-transfected cells weir week, and no significant differences were noticed among these three groups （all P 〉 0.05）. However, MRP2 expression was remarkably elevated in H DAC1 siRNA-transfected cells, which displayed an almost 3.19-fold changes in comparison with the control siRNA-transfected cells （P 〈 0.001 ）. Conclusions： HDACs inhibition could up-regulate placental MRP2 expression in ritzy, and HDAC 1 was probably to be involved in this process.

EXPRESSION AND CLINICAL SIGNIFICANCE OF MULTIDRUG RESISTANCE GENE AND MULTIDRUG RESISTANCE-ASSOCIATEDPROTEIN GENE IN ACUTE LEUKEMIA

Objective: To evaluate the expression and clinical significance of multidrug resistance gene (mdr1) and multidrug resistance-associated protein (MRP) gene in acute leukemia. Methods: The expression of mdr1 and MRP assay in 55 patients with acute leukemia (AL) by reverse transcription polymerase chain reaction (RT-PCR). Results: The mdr1 and MRP gene expression levels in the relapsed AL and the blastic plastic phases of CML were significantly higher than those in the newly diagnostic AL and controls. The mdr1 and MRP gene expression levels in the clinical drug-resistant group were significantly higher than those in the non-drug-resistant group. The complete remission (CR) rate in patients with high mdr1 expression (14.3%) was significantly lower than that with low mdr1 expression (57.5%); similarly the CR rate in patients with high MRP level was also lower than that with low MRP level. Using both high expression of mdr1 and MRP gene as the indicator for evaluating multidrug resistance (MDR), the positive predictive value and accuracy increased in comparison with single gene high expression. Conclusion: Elevated level of mdr1 or MRP gene expression might be unfavorable prognostic factors for AL patient and may be used as an important index for predicting drug-resistance and relapse in AL patient. Measuring both mdr1 and MRP gene expression would increase accuracy and sensibility of evaluating MDR in acute leukemia.

EXPRESSION OF MULTIDRUG RESISTANCE-ASSOCIATED PROTEIN (MRP) AND ITS RELATIONSHIP WITH CLINICOPATHOLOGICAL FACTORS IN NON-SMALL CELL LUNG CANCER

Objective: To investigate the relationship between the expression of multidrug resistance-associated protein (MRP) and clinicopathological factors and prognosis. Methods: The expression of MRP in 62 cases with non-small cell lung cancer (NSCLC) was detected using immunohistochemistry method. The expression of MRP in 30 cases of NSCLC and corresponding normal lung tissues were detected using immunohistochemistry and Western Blot. Results: this study of tumor tissues confirmed the plasma membrane and/or cytoplasm locations of MRP. There was apparent difference between normal lung tissues and NSCLC in MRP. The survival analysis of 62 NSCLC showed that the mean survival time of the patients with negative MRP expression was 69.8117.41 months and that of patients with positive MRP expression, 25.384.46 months. Log-rank test suggested that the difference between them was significant (P=0.0156). It was also found that in squamous cell lung cancer the statistically significant difference between the mean survival time of patients with positive MRP expression and those with negative MRP expression (P=0.0153). Multivariate Cox model analysis suggested that the survival time was significantly related to expression of MRP (P=0.035) and lymphatic metastasis (P=0.038). Conclusion: MRP expression in NSCLC is significantly higher compared with normal lung tissues. The mean survival time of patients with negative MRP was relative longer and expression of MRP was an independent factor for prognosis.

JNK1,JNK2,and JNK3 are involved in P-glycoprotein-mediated multidrug resistance of hepatocellular carcinoma cells

BACKGROUND:Multidrug resistance(MDR)is extremely common in hepatocellular carcinoma(HCC)and is a major problem in cancer eradication by limiting the efficacy of chemotherapy.Modulation of c-Jun NH2-terminal kinase(JNK)activation could be a new method to reverse MDR.However,the relationship between JNK activity and MDR in HCC cells is unknown.This study aimed to explore the relationship between MDR and JNK in HCC cell lines with different degrees of MDR.METHODS:A MDR human HCC cell line,SMMC-7721/ ADM,was developed by exposing parental cells to gradually increasing concentrations of adriamycin.The MTT assay was used to determine drug sensitivity.Flow cytometry was used to analyze the cell cycle distribution and to measure the expression levels of P-glycoprotein(P-gp)and MDR-related protein(MRP)-1 in these cells.JNK1,JNK2 and JNK3 mRNA expression levels were quantified by real-time PCR.Expression and phosphorylation of JNK1,JNK2,and JNK3 were analyzed by Western blotting.RESULTS:The MDR of SMMC-7721/ADM cells resistant to 0.05 mg/L adriamycin was mainly attributed to the overexpression of P-gp but not MRP1.In addition,these cells had a significant increase in percentage in the S phase,accompanied by a decrease in percentage in the G0/G1 phase,which is likely associated with a reduced ability for cell proliferation and MDR generation.We found that JNK1,JNK2,and JNK3 activities were negatively correlated with the degree of MDR in HCC cells.CONCLUSION:This study suggests that JNK1,JNK2,and JNK3 activities are negatively correlated with the degree of MDR in HCC cells.

Down-regulation of extracellular signal-regulated kinase 1/2 activity in P-glycoprotein-mediated multidrug resistant hepatocellular carcinoma cells

AIM： To study the expression and phosphorylation of extracellular signal-regulated kinase （ERK） i and ERK2 in multidrug resistant （MDR） hepatocellular carcinoma （HCC） cells.METHODS： MDR HCC cell lines, HepG2/adriamycin （ADM） and SMMC7721/ADM, were developed by exposing parental cells to stepwise increasing concentrations of ADM. MTT assay was used to determine drug sensitivity. Flow cytometry was employed to analyze cell cycle distribution and measure cell P-glycoprotein （P-gp） and multidrug resistant protein 1 （MRP1） expression levels. ERK1 and ERK2 mRNA expression lev-ls were measured by quantitative real-time PCR （QRTPCR）. Expression and phosphorylation of ERK1 and ERK2 were analyzed by Western blot.RESULTS： MTT assay showed that HepG2/ADM andSMMC7721/ADM were resistant not only to ADM, but also to multiple anticancer drugs. The P-gp expression was over 10-fold higher in HepG2/ADM cells than in HepG2 cells （8.92% ±0.22% vs 0.88% ± 0.05%, P 〈 0.001） and over 4-fold higher in SMMC7721/ADM cells than in SMMC7721 cells （7.37% ± 0.26% vs 1.74% ± 0.25%, P 〈 0.001）. However, the MRP1 expression was not significantly higher in HepG2/ADM and SMMC7721/ADM cells than in parental cells. In addition, the percentage of MDR HepG2/ADM and SMMC7721/ADM cells was significantly decreased in the G0/G1 phase and increased in the the S phase or G2/M phase. QRT-PCR analysis demonstrated that the ERK1 and ERK2 mRNA expression increased apparently in HepG2/ADM cells and decreased significantly in SMMC7721/ADM cells. Compared with the expression of parental cells, ERK1 and ERK2 protein expressions were markedly decreased in SMMC7721/ADM cells. However, ERK2 protein expression was markedly increased while ERK1 protein expression had no significant change in HepG2/ADM cells. Phosphorylation of ERK1 and ERK2 was markedly decreased in both HepG2/ADM and SMMC7721/ADM MDR cells.CONCLUSION： ERK1 and ERK2 activities are downregulated in P-gp-mediated MDR HCC cells. ERK1 or ERK2 might be a potential drug target for circumventing MDR HCC cells,

Expression and significance of multi-drug resistance-associated protein 3 in different tumor cell lines

Objective To investigate the expression and meaning of MRP3 in different tumor cells. MethodsThe monoclonal antibody against MRP3 was used to identify the expression of MRP3 by flow cytometer in seven tumor cells and human embryo kidney cell lines 293T.And RT-PCR was used to detect the mRNA of MRP3 in eight cell lines. ResultsThe mRNA of MRP3 was expressed in three pancreatic carcinoma cell lines.MRP3 protein was observed in BxPC-3 and AsPC-1 cells. ConclusionMRP3 may express in different tumor in tissue-specific manner.BxPC-3 and AsPC-1 may serve as cellular models for in vitro studies on multidrug resistance of pancreatic carcinoma.

菌草灵芝多糖肽对Caco-2细胞MDR1、MRP2基因表达水平的影响

使用CCK-8比色法研究菌草灵芝多糖肽(JCGLPP)对人结肠腺癌上皮细胞(Caco-2)存活率的影响;采用PCR检测JCGLPP作用不同时间后对Caco-2细胞中P-糖蛋白的编码基因MDR1和多药耐药相关蛋白-2的编码基因MRP2表达水平的影响.结果显示:0.1~500μg·mL^(-1)JCGLPP对Caco-2细胞无毒性;10μg·mL^(-1)JCGLPP作用1~48 h能抑制MDR1基因的表达,对MRP2基因的表达呈先抑后扬的趋势.表明JCGLPP可抑制MDR1基因的表达,对MRP2基因表达的影响与其作用时间有关.

基于OCT2、MRP2探讨加味生脉饮对Lewis肺癌小鼠顺铂化疗的增效减毒机制

【目的】观察加味生脉饮对顺铂化疗Lewis肺癌小鼠有机阳离子转运体2(OCT2)、多药耐药相关蛋白2(MRP2)的影响,探讨其对Lewis肺癌小鼠顺铂化疗的增效减毒机制。【方法】采用腋窝皮下接种Lewis肺癌细胞(LLC)构建肺癌移植瘤小鼠模型,造模成功后随机分为对照组、顺铂组、联合组(顺铂联合加味生脉饮)和生脉饮组,每组7只小鼠,给药14 d。观察4组小鼠一般状态、肿瘤生长情况,肿瘤、肾脏组织病理学以及血清尿素氮(BUN)、肌酐(Cr)浓度。通过免疫组织化学染色(IHC)和Western Blot的方法检测OCT2、MRP2蛋白表达情况,并使用高效液相色谱串联质谱(HPLC-MS/MS)法测定肾脏和肿瘤组织中顺铂含量。【结果】(1)给药结束后,各组小鼠体质量均有下降,顺铂组下降幅度最大,顺铂组体质量变化显著高于联合组、生脉饮组(P<0.05),生脉饮组和联合组小鼠一般状态均优于对照组和顺铂组。(2)干预结束时,顺铂组肿瘤体积和质量小于生脉饮组和对照组,联合组肿瘤体积和质量显著小于顺铂组(P<0.05)。(3)组织病理学结果显示:生脉饮组、对照组肿瘤细胞结构清晰,细胞形态正常;顺铂组与联合组可见肿瘤细胞坏死,肿瘤细胞边缘模糊,联合组肿瘤细胞坏死面积更大。生脉饮组、对照组肾脏细胞形态正常;联合组肾脏细胞损伤较轻,无明显病变;顺铂组肾组织明显病变,肾小管上皮细胞边缘模糊。(4)顺铂组小鼠血清BUN、Cr水平显著高于其他3组(P<0.05)。(5)顺铂组肾脏组织OCT2表达相比对照组显著增加,联合组OCT2表达相比顺铂组显著降低(均P<0.05);顺铂组肿瘤组织MRP2表达相比对照组显著增加,联合组MRP2表达相比顺铂组显著降低(均P<0.05)。(6)联合组肿瘤组织中顺铂含量显著高于顺铂组,联合组肾脏组织中顺铂含量显著低于顺铂组(均P<0.05)。【结论】OCT2、MRP2在顺铂肾脏毒性与耐药性中起重要的调控作用,加味生脉饮可能通过抑制肾脏中OCT2与肿瘤细胞中MRP2的蛋白表达,降低了顺铂治疗的肾脏毒性,提高了顺铂的抗肿瘤效果。

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 Lut对K562/ADR细胞的增殖抑制率<10%,为无毒性的Lut浓度。与0μmol/L Lut组相比,2、4μmol/L Lut组可明显增强ADR对K562/ADR的细胞增殖抑制率,增加细胞内ADR蓄积量,提高逆转耐药倍数,降低细胞内GSH含量,下调细胞中MRP1、P-gp、GST-pi、Nrf2 mRNA及蛋白的表达(P<0.05);且4μmol/L Lut作用效果较2μmol/L Lut更显著。结论Lut可抑制K562/ADR细胞增殖,逆转其对ADR的耐药性,其机制可能与Lut下调Nrf2、MRP1、P-gp、GST-pi表达,进而增加细胞内ADR蓄积量有关。

ADA、PGLYRP2及PCT在耐多药肺结核诊断中的潜在价值

目的探讨腺苷脱氨酶(ADA)、肽聚糖识别蛋白2(PGLYRP2)及降钙素原(PCT)在耐多药肺结核诊断中的潜在价值,以期为临床治疗提供参考。方法选取2019年5月—2022年1月在河南省禹州市疾病预防控制中心门诊就诊的110例耐多药肺结核患者作为耐药组,同期选择在本院门诊就诊的首次发现痰检结核杆菌阳性且无耐药史的肺结核患者110例作为敏感组。分析ADA、PGLYRP2、PCT在耐多药肺结核诊断中的潜在价值。结果耐药组患者PGLYRP2、PCT水平高于敏感组,而ADA水平低于敏感组,差异均有统计学意义(P<0.05)。ROC显示:ADA、PGLYRP2、PCT诊断耐多药肺结核的AUC分别为0.773(95%CI:0.700~0.845)、0.789(95%CI:0.707~0.871)、0.804(95%CI:0.669~0.939)。ADA的Cut-off=16.92 U/L、PGLYRP2的Cut-off=544.62 pg/mL、PCT的Cut-off=0.58 ng/mL,在该阈值下,诊断的灵敏度和特异度最高。结论PGLYRP2、PCT在耐多药肺结核患者体内呈高表达状况,ADA呈低表达状况,ADA、PGLYRP2、PCT水平与耐多药肺结核的发生存在相关性,可用于诊断耐多药肺结核。

肺癌组织中耐药相关蛋白和p53 bcl-2表达及其意义

目的:探讨肺癌组织中耐药相关蛋白和p53、bcl-2表达及其意义。方法:应用免疫组化技术检测治疗前73例肺癌组织标本中P-gp、MRP、LRP、GST-π、p53和bcl-2表达。结果:非小细胞肺癌组P-gp、LRP、MRP+LRP、P-gp+p53的蛋白表达明显高于小细胞肺癌组(P<0.05)。腺癌组MRP、LRP、MRP+LRP、MRP+LRP+GST-π、MRP+LRP+P-gp+GST-π蛋白阳性表达高于鳞状细胞癌组、小细胞肺癌组(P<0.05),MRP+GST-π共表达者高于鳞状细胞癌组(P<0.01),P-gp+p53共表达者高于小细胞肺癌组(P<0.05),bcl-2蛋白阳性表达低于鳞状细胞癌组、小细胞肺癌组(P<0.05)。鳞状细胞癌组P-gp、P-gp+p53、P-gp+bcl-2的蛋白表达明显高于小细胞肺癌组(P<0.05)。P-gp与p53、bcl-2蛋白阳性表达呈正相关(P<0.05)。p53与bcl-2蛋白阳性表达呈正相关(P<0.01)。MRP与GST-π蛋白阳性表达呈正相关(P<0.05)。结论:肺癌耐药为一多途径多基因参与的过程,P-gp、LRP、MRP、GST-π、p53、bcl-2表达及其共表达可作为监测肺癌细胞原发性耐药的指标。

ABCG2食管癌耐药细胞系Eca109/ABCG2的建立

目的探讨腺苷三磷酸结合转运蛋白G超家族成员2(ABCG2)在介导食管癌多药耐药中的作用。方法扩增ABCG2基因,与pcDNA3.1载体连接,构建pcDNA3.1-ABCG2重组质粒,转染Eca109细胞后用G418筛选稳定转染细胞。采用流式细胞术检测细胞内阿霉素的含量,评价细胞对药物的外排作用。MTT法检测阿霉素对Eca109/ABCG2、Eca109/pcDNA3.1、Eca109细胞生长的抑制作用,并计算半数抑制浓度(IC50)和细胞的耐药指数。采用Western blotting和RT-PCR法检测细胞中ABCG2蛋白及mRNA的表达量。结果成功建立转染ABCG2基因的Eca109/ABCG2细胞。Eca109/ABCG2细胞中ABCG2的mRNA和蛋白表达量升高。阿霉素对Eca109/ABCG2、Eca109/pcDNA3.1、Eca109细胞的IC50值分别为18.61±3.94、4.18±0.14、4.69±0.88μg/ml。Eca109/AB-CG2细胞对阿霉素的耐药指数为3.97,且外排阿霉素的作用增强。结论Eca109/ABCG2细胞具有ABCG2的耐药表型,能够稳定表达ABCG2蛋白,可作为研究ABCG2介导的多药耐药相关机制的细胞模型。

利福平对小鼠肝细胞胆汁酸转运体Bsep和Mrp2表达与定位的影响

目的利福平(Rifampicin,RIF)具有肝毒性,但其机制尚不清楚。本研究在RIF诱导的肝内胆汁淤积小鼠中,探讨RIF对肝细胞胆汁酸转运体胆汁酸输出泵(bile salt exportpump,Bsep)和多药抵抗相关蛋白-2(multidrug resistance-associated protein-2,Mrp2)表达和定位影响。方法 48只♀ICR小鼠随机分为4组,RIF1wk组:经灌胃给予RIF(200mg.kg-1.d-1),连续1周,于末次给药后6h取材;RIF6h组:单次灌胃给予RIF(200mg.kg-1)后6h取材;RIF1周对照组(CON1wk)与RIF6h对照组(CON6h):经灌胃给予等容积生理盐水。所有小鼠均收集血液和肝组织,常规生化检测血清丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)、碱性磷酸酶(ALP)、总胆红素(TB)和结合胆红素(DB),并检测小鼠血清和肝组织总胆汁酸(TBA)水平。HE染色分析肝组织病理改变。RT-PCR测定肝脏肝细胞胆汁酸转运体Bsep和Mrp2mRNA表达。免疫荧光法分析Bsep和Mrp2在肝细胞的位置。结果给予RIF1周后,小鼠血清TB由(1.25±0.69)μmol.L-1上升至(65.73±12.08)μmol.L-1,上升近70倍,DB由(0.77±0.40)μmol.L-1上升至(53.33±12.43)μmol.L-1,上升约80倍,ALP由(110.2±13.8)U.L-1上升至(279.5±80.4)U.L-1,上升约1.5倍,TBA由(3.15±0.89)μmol.L-1上升至(13.54±6.51)μmol.L-1,上升约5倍并伴有血清ALT和AST轻度升高;肝脏组织TBA由(0.15±0.04)μmol.g-1liver上升至(0.30±0.19)μmol.g-1liver,上升约2倍;肝脏组织HE染色显示肝细胞出现脂肪变性、轻度坏死和炎症。单次给予RIF6h后血清TB、DB、ALP、ALT、AST和TBA明显上升,但未观察到小鼠肝脏组织病理发生改变。免疫荧光分析显示,给予小鼠RIF1wk与单次给予RIF6h后肝细胞中Bsep和Mrp2的定位发生了改变。而无论单次给予RIF还是连续给药1周,肝细胞Bsep和Mrp2mRNA表达水平均未发生变化。结论肝细胞胆汁酸转运体Bsep和Mrp2定位改变可能是RIF诱发肝内胆汁淤积的重要机制。

含扶正解毒汤药血清对白血病K562/A02耐药细胞的抑制作用及初步机制

目的:探讨含扶正解毒汤药血清对白血病耐药细胞株K562/A02的抑制效果及可能的机制。方法:采用M TT法检测含扶正解毒汤药血清对K562/A02耐药细胞的生长抑制率,流式细胞技术测定含扶正解毒汤药血清处理各组K562/A02细胞后的凋亡情况,QPCR法检测BCL-2 mRNA的表达,Western blot方法检测BCL-2蛋白的表达,流式细胞技术测定细胞膜P-gp蛋白的表达。结果:MTT细胞毒实验结果表明含扶正解毒汤药血清具有抑制k562/A02细胞生长的效果,且抑制率呈药物浓度相关性;流式细胞检测结果表明含扶正解毒汤药血清可以诱导k562/A02耐药细胞的凋亡,凋亡率呈药物浓度相关性;Q-PCR结果显示,含扶正解毒汤药血清可以下调K562/A02细胞BCL-2蛋白的表达;流式细胞检测结果表明,含扶正解毒汤药血清可下调K562/A02细胞膜P-gp蛋白的表达。结论:含扶正解毒汤药血清可以促进K562/A02耐药细胞的凋亡,其诱导细胞凋亡的机制可能与抑制BCL-2蛋白和P-gp蛋白的表达有关。

P-gp、MRP、LRP、P53及c-erbB-2在非小细胞肺癌中的表达

目的:探讨P糖蛋白(P-gp)、多药耐药相关蛋白(MRP)、肺耐药蛋白(LRP)、P53蛋白及c-erbB-2蛋白在术前未经治疗的非小细胞肺癌(NSCLC)中的表达及相互间的关系。方法:采用免疫组化法检测78例NSCLC癌组织及15例癌旁肺组织(距癌灶5 cm)中P-gp、MRP、LRP、P53及c-erbB-2的蛋白表达情况。结果:免疫组化显示P-gp、MRP、LRP、P53及c-erbB-2在肺癌组织中的阳性表达率分别是65.4%(51/78)、39.7%(31/78)、56.4%(44/78)、53.8%(42/78)及43.6%(34/78),均显著高于癌旁肺组织中的表达水平(P<0.05);MRP和LRP蛋白表达在不同病理类型(腺癌、鳞癌及大细胞癌)之间比较均具有显著性差异(P分别为0.008和<0.001),LRP及P53蛋白表达在不同病理分化程度之间具有显著性差异(P分别为0.025和0.026);c-erbB-2表达与P-gp、MRP、LRP、P53均有相关性(Spearman相关系数分别为0.317、0.401、0.519和0.341,P值分别为0.005、<0.001、<0.001和0.002),P53与MRP之间(Spearman相关系数为=0.260,P=0.022)以及LRP与MRP之间(Spearman相关系数为0.371,P=0.001)有相关性。结论:P-gp、MRP、LRP、P53及c-erbB-2这些蛋白的表达在NSCLC的多药耐药形成及肿瘤的发生发展中可能具有一定的协同作用。

葛根芩连汤有效成分对黄芩苷在Caco-2细胞模型中吸收转运的影响

目的采用LC-MS/MS法研究葛根芩连汤(葛根、黄芩、黄连、甘草)有效成分对黄芩苷在Caco-2细胞模型中吸收转运的影响。方法建立Caco-2细胞模型,采用细胞摄取实验和细胞转运实验评价多药耐药相关蛋白(MRP2)的功能。结果摄取实验中,黄芩苷的摄取量在60 min基本达到饱和[(0.68±0.07)ng/μg],加入MRP2抑制剂MK-571之后,黄芩苷的摄取量显著升高[(1.10±0.02)ng/μg,P<0.01],而P-gp转运蛋白抑制剂维拉帕米无此效果。配伍葛根素能提高黄芩苷的摄取量(P<0.05),而小檗碱、甘草苷的作用有统计学意义。细胞转运实验的结果表明,加入MRP2转运蛋白抑制剂后能增加黄芩苷从肠腔侧(AP)到基底侧(BL)侧的转运。配伍葛根素、甘草苷后能促进黄芩苷从AP到BL侧的转运,小檗碱无明显影响。结论 MRP2转运蛋白调控Caco-2细胞摄取吸收黄芩苷,推测其可能为MRP2转运蛋白的底物。葛根素可使在Caco-2细胞中黄芩苷被外排的量减少,从而增加黄芩苷的吸收量。

甘草提取物对小鼠肝脏核因子E2相关因子2及其下游基因表达的影响

目的考察甘草提取物对核因子E2相关因子2(Nrf2)信号通路及其下游基因尿苷二磷酸葡糖醛酸转移酶1A1(UGT1A1)、γ谷氨酰半胱胺酸合成酶(γGCS)、多药耐药相关蛋白1(MRP1)和多药耐药相关蛋白2(MRP2)的影响。方法 12只小鼠随机分为对照组和甘草提取物组(150 mg·kg-1)。给药后24 h处死取肝组织,采用qRT-PCR技术检测小鼠肝中Nrf2、UGT1A1、γGCS、MRP1和MRP2 mRNA的表达;Western blot技术测定Nrf2蛋白的表达。结果与对照组比较,甘草提取物显著诱导了小鼠肝脏中Nrf2 mRNA和蛋白的表达,同时Nrf2下游基因UGT1A1、γGCS、MRP1和MRP2 mRNA的表达也显著提高(均P<0.05)。结论甘草提取物诱导了小鼠肝脏中II相解毒酶UGT1A1、γGCS及转运体MRP1、MRP2,其机制可能与上调Nrf2转录因子的表达,激活Nrf2细胞信号转导通路有关。

茵栀黄颗粒对胆管结扎大鼠肝细胞膜转运体Mrp2、Ntcp及Bsep表达的影响

目的通过考察茵栀黄颗粒(茵陈、栀子、金银花和黄芩)对肝细胞膜转运体多药耐药相关蛋白2(Multidrugresistance-associated protein 2,Mrp2/ABCC2)、Na+-牛黄胆酸共转运多肽(Na+/taurocholate cotransporter,Ntcp/SLC10A1)及胆盐输出泵(Bile salt export pump,Bsep/ABCB11)表达的影响。方法胆管结扎术制备胆汁淤积大鼠模型;生化检测和HE染色,观察茵栀黄颗粒的干预效果;流式细胞仪测定肝脏转运体Ntcp、Bsep和Mrp2的表达。结果与模型组相比,茵栀黄组肝细胞的脂肪病变和水肿较模型组显著减轻(P<0.05),Mrp2的表达显著升高(P<0.01);但Ntcp、Bsep的表达无明显变化。结论肝细胞膜转运体Mrp2的表达升高可能是茵栀黄颗粒的退黄利胆分子机制之一。

HO-1与MRP2在原发性胆囊癌组织中的表达和意义

目的:检测血红素加氧酶-1(heme oxygenase,HO-1)与多药耐药相关蛋白2(multidrug resistance-associated protein2,MRP2)在原发性胆囊癌组织中的表达,探讨其与胆囊癌发生、发展的关系。方法:采用免疫组化SP法检测67例原发性胆囊癌患者中HO-1和MRP2的表达水平。结果:原发胆囊癌组织HO-1和MRP2表达的总阳性率分别为73.1%、77.6%。其中腺癌的阳性率为76.7%和80%。依据病理分级,HO-1和MRP2表达水平由高到低分别为III级>II级>I级,且具有统计学差异(P=0.028,P=0.023);HO-1、MRP2的阳性表达与年龄、性别等临床特征无相关性;HO-1和MRP2表达之间具有良好的相关性(r=0.324,P=0.005)。结论:HO-1和MRP2在原发性胆囊癌组织高表达,对胆囊癌的发生、发展提供有利条件,二者之间表达具有良好的相关性。

HAPLN1通过IKK/p65信号通路诱导大肠癌HT-29细胞产生MTX耐药

目的:研究甲氨蝶呤(methotrexate,MTX)耐药前后人大肠癌(结直肠癌)HT-29细胞中透明质酸蛋白聚糖连结蛋白1(hyaluronan and proteoglycan link protein 1,HAPLN1)表达的变化及其对MTX耐药性的影响,并探究可能的分子机制。方法:采用浓度梯度递增法构建耐药细胞株HT-29/MTX;RT-PCR检测HAPLN1和多药耐药相关蛋白2(multidrug resistance-associated protein 2,MRP2)的mRNA表达水平;采用脂质体介导法将人HAPLN1和MRP2基因的干扰质粒转染HT-29/MTX细胞并筛选出稳定表达的细胞系;采用CCK-8法检测细胞活力;流式细胞术检测细胞凋亡;采用Western blot检测HAPLN1、MRP2、IκB激酶(IκB kinase,IKK)α/β、p-IKKα/β(Ser176/Ser177)、p65和p-p65(Ser536)的蛋白水平。结果:HT-29/MTX细胞中HAPLN1和MRP2的mRNA和蛋白表达水平都显著高于其亲代HT-29细胞(P<0.05),耐药倍数高达463.756。抑制HAPLN1和MRP2基因表达使MTX对HT-29/MTX细胞的IC_(50)从15.304μmol/L分别降至6.119μmol/L和7.801μmol/L,逆转倍数分别为2.501和1.962,并增强MTX诱导的细胞凋亡(P<0.05)。敲减HAPLN1基因表达和使用IKK抑制剂IKK16均可下调IKKα/β和p65蛋白磷酸化水平以及MRP2蛋白表达水平(P<0.05),但IKK16未对HAPLN1蛋白表达产生影响(P>0.05)。结论:敲减HAPLN1基因表达可在体外增强人大肠癌耐药细胞株HT-29/MTX对MTX的敏感性,这可能与其抑制IKK/p65信号通路活化,继而下调MRP2基因表达有关。