BACKGROUND Trastuzumab constitutes the fundamental component of initial therapy for patients with advanced human epidermal growth factor receptor 2(HER-2)-positive gastric cancer(GC).However,the efficacy of this treat...BACKGROUND Trastuzumab constitutes the fundamental component of initial therapy for patients with advanced human epidermal growth factor receptor 2(HER-2)-positive gastric cancer(GC).However,the efficacy of this treatment is hindered by substantial challenges associated with both primary and acquired drug resistance.While S-phase kinase associated protein 2(Skp2)overexpression has been implicated in the malignant progression of GC,its role in regulating trastuzumab resistance in this context remains uncertain.Despite the numerous studies investigating Skp2 inhibitors among small molecule compounds and natural products,there has been a lack of successful commercialization of drugs specifically targeting Skp2.AIM To discover a Skp2 blocker among currently available medications and develop a therapeutic strategy for HER2-positive GC patients who have experienced progression following trastuzumab-based treatment.METHODS Skp2 exogenous overexpression plasmids and small interfering RNA vectors were utilized to investigate the correlation between Skp2 expression and trastuzumab resistance in GC cells.Q-PCR,western blot,and immunohistochemical analyses were conducted to evaluate the regulatory effect of thioridazine on Skp2 expression.A cell counting kit-8 assay,flow cytometry,a amplex red glucose/glucose oxidase assay kit,and a lactate assay kit were utilized to measure the proliferation,apoptosis,and glycolytic activity of GC cells in vitro.A xenograft model established with human GC in nude mice was used to assess thioridazine's effectiveness in vivo.RESULTS The expression of Skp2 exhibited a negative correlation with the sensitivity of HER2-positive GC cells to trastuzumab.Thioridazine demonstrated the ability to directly bind to Skp2,resulting in a reduction in Skp2 expression at both the transcriptional and translational levels.Moreover,thioridazine effectively inhibited cell proliferation,exhibited antiapoptotic properties,and decreased the glucose uptake rate and lactate production by suppressing Skp2/protein kinase B/mammalian target of rapamycin/glucose transporter type 1 signaling pathways.The combination of thioridazine with either trastuzumab or lapatinib exhibited a more pronounced anticancer effect in vivo,surpassing the efficacy of either monotherapy.CONCLUSION Thioridazine demonstrates promising outcomes in preclinical GC models and offers a novel therapeutic approach for addressing trastuzumab resistance,particularly when used in conjunction with lapatinib.This compound has potential benefits for patients with Skp2-proficient tumors.展开更多
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 regul...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.展开更多
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...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。展开更多
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(B...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。展开更多
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...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。展开更多
目的:探讨糖皮质激素(glucocorticoid,GC)、免疫抑制剂在IgA肾病应用中的耐药机制,以提高临床诊治水平和判断预后的综合能力。方法:经肾活检诊断为IgA肾病(综合临床排除继发性IgA肾病)患者作为研究对象,按临床诊断和临床标准接受GC、免...目的:探讨糖皮质激素(glucocorticoid,GC)、免疫抑制剂在IgA肾病应用中的耐药机制,以提高临床诊治水平和判断预后的综合能力。方法:经肾活检诊断为IgA肾病(综合临床排除继发性IgA肾病)患者作为研究对象,按临床诊断和临床标准接受GC、免疫抑制剂治疗,观察疗效。治疗前留取外周血,提取细胞总RNA,通过实时荧光定量PCR(Real-Ti meRT-PCR)技术,测定IgA肾病患者外周血P-糖蛋白(P-glycoprotein,P-gp)、多药耐药相关蛋白2(multidrug resistance-associated protein 2,MRP2)mRNA表达,分析P-gp、MRP2 mRNA水平与GC、免疫抑制剂临床疗效和24 h蛋白尿(24 h UP)、肾小球滤过率(GFR)的相关性。结果:缓解组、显效组IgA肾病患者外周血P-gp mRNA平均显著低于有效组和无效组,有效组又显著低于无效组。患者外周血P-gp mRNA与治疗前24 h UP、GFR均无显著相关性,而与治疗后24 h UP呈显著正相关,与GFR呈显著负相关。缓解组患者MRP2 mRNA显著低于有效组和无效组,显效组显著低于无效组。MRP2 mRNA与治疗前24 h UP、GFR均无显著相关性,与治疗后24 h UP呈显著正相关,与GFR无显著相关。结论:IgA肾病患者外周血细胞P-gp、MRP2的高水平表达可能参与了GC、免疫抑制剂的耐药机制,影响了临床疗效。治疗前测定IgA肾病患者外周血P-gp、MRP2 mRNA表达对预测激素、免疫抑制剂的疗效有一定的参考价值。抑制IgA肾病患者外周血P-gp、MRP2的高表达则可能为提高临床疗效开辟另一途径。展开更多
基金Supported by Youth Fund of National Natural Science Foundation of China,No.81803575,No.31902287Kaifeng Science and Technology Development Plan Project,No.2203008+2 种基金Key Specialized Research and Promotion Project of Henan Province in 2023,No.232102311205Henan Medical Science and Technology Research Program Project,No.LHGJ20210801College Students Innovation and Entrepreneurship Training Program of Henan University,No.20231022007.
文摘BACKGROUND Trastuzumab constitutes the fundamental component of initial therapy for patients with advanced human epidermal growth factor receptor 2(HER-2)-positive gastric cancer(GC).However,the efficacy of this treatment is hindered by substantial challenges associated with both primary and acquired drug resistance.While S-phase kinase associated protein 2(Skp2)overexpression has been implicated in the malignant progression of GC,its role in regulating trastuzumab resistance in this context remains uncertain.Despite the numerous studies investigating Skp2 inhibitors among small molecule compounds and natural products,there has been a lack of successful commercialization of drugs specifically targeting Skp2.AIM To discover a Skp2 blocker among currently available medications and develop a therapeutic strategy for HER2-positive GC patients who have experienced progression following trastuzumab-based treatment.METHODS Skp2 exogenous overexpression plasmids and small interfering RNA vectors were utilized to investigate the correlation between Skp2 expression and trastuzumab resistance in GC cells.Q-PCR,western blot,and immunohistochemical analyses were conducted to evaluate the regulatory effect of thioridazine on Skp2 expression.A cell counting kit-8 assay,flow cytometry,a amplex red glucose/glucose oxidase assay kit,and a lactate assay kit were utilized to measure the proliferation,apoptosis,and glycolytic activity of GC cells in vitro.A xenograft model established with human GC in nude mice was used to assess thioridazine's effectiveness in vivo.RESULTS The expression of Skp2 exhibited a negative correlation with the sensitivity of HER2-positive GC cells to trastuzumab.Thioridazine demonstrated the ability to directly bind to Skp2,resulting in a reduction in Skp2 expression at both the transcriptional and translational levels.Moreover,thioridazine effectively inhibited cell proliferation,exhibited antiapoptotic properties,and decreased the glucose uptake rate and lactate production by suppressing Skp2/protein kinase B/mammalian target of rapamycin/glucose transporter type 1 signaling pathways.The combination of thioridazine with either trastuzumab or lapatinib exhibited a more pronounced anticancer effect in vivo,surpassing the efficacy of either monotherapy.CONCLUSION Thioridazine demonstrates promising outcomes in preclinical GC models and offers a novel therapeutic approach for addressing trastuzumab resistance,particularly when used in conjunction with lapatinib.This compound has potential benefits for patients with Skp2-proficient tumors.
文摘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.
文摘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。
文摘目的: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。
文摘目的:探讨糖皮质激素(glucocorticoid,GC)、免疫抑制剂在IgA肾病应用中的耐药机制,以提高临床诊治水平和判断预后的综合能力。方法:经肾活检诊断为IgA肾病(综合临床排除继发性IgA肾病)患者作为研究对象,按临床诊断和临床标准接受GC、免疫抑制剂治疗,观察疗效。治疗前留取外周血,提取细胞总RNA,通过实时荧光定量PCR(Real-Ti meRT-PCR)技术,测定IgA肾病患者外周血P-糖蛋白(P-glycoprotein,P-gp)、多药耐药相关蛋白2(multidrug resistance-associated protein 2,MRP2)mRNA表达,分析P-gp、MRP2 mRNA水平与GC、免疫抑制剂临床疗效和24 h蛋白尿(24 h UP)、肾小球滤过率(GFR)的相关性。结果:缓解组、显效组IgA肾病患者外周血P-gp mRNA平均显著低于有效组和无效组,有效组又显著低于无效组。患者外周血P-gp mRNA与治疗前24 h UP、GFR均无显著相关性,而与治疗后24 h UP呈显著正相关,与GFR呈显著负相关。缓解组患者MRP2 mRNA显著低于有效组和无效组,显效组显著低于无效组。MRP2 mRNA与治疗前24 h UP、GFR均无显著相关性,与治疗后24 h UP呈显著正相关,与GFR无显著相关。结论:IgA肾病患者外周血细胞P-gp、MRP2的高水平表达可能参与了GC、免疫抑制剂的耐药机制,影响了临床疗效。治疗前测定IgA肾病患者外周血P-gp、MRP2 mRNA表达对预测激素、免疫抑制剂的疗效有一定的参考价值。抑制IgA肾病患者外周血P-gp、MRP2的高表达则可能为提高临床疗效开辟另一途径。
