Introduction:ATP-binding cassette subfamily B member 1(ABCB1) and subfamily C member 10(ABCCIO) proteins are efflux transporters that couple the energy derived from ATP hydrolysis to the translocation of toxic substan...Introduction:ATP-binding cassette subfamily B member 1(ABCB1) and subfamily C member 10(ABCCIO) proteins are efflux transporters that couple the energy derived from ATP hydrolysis to the translocation of toxic substances and chemotherapeutic drugs out of cells.Cabazitaxel is a novel taxane that differs from paclitaxel by its lower affinity for ATP-binding cassette(ABC) transporters.Methods:We determined the effects of cabazitaxel,a novel tubulin-binding taxane,and paclitaxel on paclitaxelresistant,ABCB1-overexpressing KB-C2 and LLC-MDR1-WT cells and paclitaxel-resistant,ABCC10-overexpressing HEK293/ABCC10 cells by calculating the degree of drug resistance and measuring ATPase activity of the ABCB1 transporter.Results:Decreased resistance to cabazitaxel compared with paclitaxel was observed in KB-C2,LLC-MDR1-WT,and HEK293/ABCC10 cells.Moreover,cabazitaxel had low efficacy,whereas paclitaxel had high efficacy in stimulating the ATPase activity of ABCB1,indicating a direct interaction of both drugs with the transporter.Conclusion:ABCB1 and ABCC10 are not primary resistance factors for cabazitaxel compared with paclitaxel,suggesting that cabazitaxel may have a low affinity for these efflux transporters.展开更多
目的ATP结合盒B亚家族成员1(ATP binding cassette subfamily B member 1,ABCB1)的异常表达在多种癌症的发生发展中发挥关键作用。然而,G蛋白偶联受体C家族5组A型(G protein coupled receptor family C group5 type A,GPRC5A)调控的ABCB...目的ATP结合盒B亚家族成员1(ATP binding cassette subfamily B member 1,ABCB1)的异常表达在多种癌症的发生发展中发挥关键作用。然而,G蛋白偶联受体C家族5组A型(G protein coupled receptor family C group5 type A,GPRC5A)调控的ABCB1表达对肺腺癌增殖的影响仍不清楚。本研究探讨了GPRC5A调控的ABCB1表达对肺腺癌增殖的影响。方法我们采用RT-PCR、Western-blot或免疫组化实验,分析ABCB1在肺腺癌细胞系、人肺腺癌组织以及GPRC5A基因敲除小鼠和野生型小鼠的气管上皮细胞和肺组织中的表达。采用细胞计数试剂盒-8(CCK-8)分析GPRC5A基因敲除小鼠气管上皮细胞对化疗药物的敏感性。采用皮下肿瘤形成实验探讨下调ABCB1表达是否可抑制体内肺腺癌增殖。采用免疫荧光和免疫沉淀实验研究GPRC5A和ABCB1之间潜在的调控关系。结果ABCB1在肺腺癌细胞系和人类肺腺癌组织中表达上调。GPRC5A基因敲除小鼠的气管上皮细胞及肺组织的ABCB1表达高于野生型小鼠。与GPRC5A野生型小鼠的气管上皮细胞相比,GPRC5A基因敲除小鼠的气管上皮细胞对塔立奇达和多柔比星更敏感。注射移植细胞28天后,接受ABCB1基因敲除细胞移植的GPRC5A-/-C57BL/6小鼠的肺肿瘤的体积和重量均明显低于野生型细胞移植小鼠(P=0.0043,P=0.0060)。此外,免疫荧光和免疫沉淀实验表明,GPRC5A通过直接结合方式调控ABCB1的表达。结论GPRC5A通过抑制ABCB1表达降低肺腺癌增殖。GPRC5A调节ABCB1表达的途径有待研究。展开更多
Mitofusin2 （Mfn2） plays a pivotal role in the proliferation and apoptosis of vascular smooth muscle cells （VSMCs）. The purpose of this study was to investigate the effects of Mfn2 on the traffick- ing of intracell...Mitofusin2 （Mfn2） plays a pivotal role in the proliferation and apoptosis of vascular smooth muscle cells （VSMCs）. The purpose of this study was to investigate the effects of Mfn2 on the traffick- ing of intracellular cholesterol in the foam ceils derived from rat VSMCs （rVSMCs） and also to investigate the effects of Mfn2 on the expression of adenosine triphosphate-binding cassette subfamily A member 1 （ABCA1）, adenosine triphosphate-binding cassette subfamily G member 1 （ABCG1） and peroxisome proliferator-activated receptor gamma （PPARy）. The rVSMCs were co-cultured with oxi- dized low density lipoprotein （LDL, 80 ~tg/mL） to produce foam cells and cholesterol accumulation in cells. Before oxidized LDL treatment, different titers （20, 40 and 60 pfu/cell） of recombinant adenovirus containing Mfn2 gene （Adv-Mfn2） were added into the culture medium for 24 h to transfect the Mfn2 gene into the rVSMCs. Then the cells were harvested for analyses. The protein expression of Mfn2 was significantly higher in Adv-Mfn2-transfected group than in untransfected group （P〈0.05）, and the ex- pression levels significantly increased when the titer of Adv-Mfn2 increased （P〈0.05）. At 24 or 48 h af- ter oxidized LDL treatment, rVSMCs became irregular and their nuclei became larger, and their plasma abounded with red lipid droplets. However, the number of red lipid droplets was significantly decreased in Adv-Mfn2-transfected group as compared with untransfected group. At 48 h after oxidized LDL treatment, the intracellular cholesterol in rVSMCs was significantly increased （P〈0.05）, but it was sig- nificantly decreased in Adv-Mfn2-transfected group as compared with untransfected group （P〈0.05）, and it also significantly decreased when the titer of Adv-Mfn2 increased （P〈0.05）. The mRNA and pro- tein expression levels of ABCA1 and ABCG1 were significantly increased in Adv-Mfn2-transfected group as compared with untransfected group （P〈0.05）. Though the mRNA and protein expression levels of PPARy was not significantly increased （P〉0.05）, the phosporylation levels of PPARy were signifi- cantly decreased in Adv-Mfn2-transfected group as compared with untransfected group （P〈0.05）. These results suggest that the transfection of Adv-Mfn2 can significantly reduce intracellular cholesterol in oxidized LDL-induced rVSMCs possibly by decreasing PPAR＇/phosporylation and then increasing pro- tein expression levels of ABCAI and ABCG1, which may be helpful to suppress the formation of foam cells.展开更多
Harlequin ichthyosis is a severe autosomal recessive skin disorder.Most deaths occur within the first few days after birth,and the survivors still have severe chronic skin disease throughout their lives.Almost all cas...Harlequin ichthyosis is a severe autosomal recessive skin disorder.Most deaths occur within the first few days after birth,and the survivors still have severe chronic skin disease throughout their lives.Almost all cases were associated with a pathogenic variant of adenosine triphosphate binding cassette transporter,subfamily A,member 12(ABCA12)gene.We described a case of HI diagnosed by ultrasound examination during the second-trimester and genetic diagnosis reveal two novel heterozygous ABCA12 mutations c.2563-2570delinsGGCAATT,p.(Leu855Glyfs*13),and c.6116delT,p.(Met2039Argfs*8)by the next-generation DNA sequencing,which further enriched our understanding of the pathogenic variation of ABCA12 gene.展开更多
基金supported by funds from the National Institutes of Health (1R15CA143701)St.John's University Research Seed Grant(579-1110-7002) to Dr.Zhe-Sheng Chen.Drs.Suneet ShuklaSuresh V.Ambudkar were supported by the Intramural Research Program,Center for Cancer Research, National Cancer Institute,National Institutes of Health
文摘Introduction:ATP-binding cassette subfamily B member 1(ABCB1) and subfamily C member 10(ABCCIO) proteins are efflux transporters that couple the energy derived from ATP hydrolysis to the translocation of toxic substances and chemotherapeutic drugs out of cells.Cabazitaxel is a novel taxane that differs from paclitaxel by its lower affinity for ATP-binding cassette(ABC) transporters.Methods:We determined the effects of cabazitaxel,a novel tubulin-binding taxane,and paclitaxel on paclitaxelresistant,ABCB1-overexpressing KB-C2 and LLC-MDR1-WT cells and paclitaxel-resistant,ABCC10-overexpressing HEK293/ABCC10 cells by calculating the degree of drug resistance and measuring ATPase activity of the ABCB1 transporter.Results:Decreased resistance to cabazitaxel compared with paclitaxel was observed in KB-C2,LLC-MDR1-WT,and HEK293/ABCC10 cells.Moreover,cabazitaxel had low efficacy,whereas paclitaxel had high efficacy in stimulating the ATPase activity of ABCB1,indicating a direct interaction of both drugs with the transporter.Conclusion:ABCB1 and ABCC10 are not primary resistance factors for cabazitaxel compared with paclitaxel,suggesting that cabazitaxel may have a low affinity for these efflux transporters.
文摘目的ATP结合盒B亚家族成员1(ATP binding cassette subfamily B member 1,ABCB1)的异常表达在多种癌症的发生发展中发挥关键作用。然而,G蛋白偶联受体C家族5组A型(G protein coupled receptor family C group5 type A,GPRC5A)调控的ABCB1表达对肺腺癌增殖的影响仍不清楚。本研究探讨了GPRC5A调控的ABCB1表达对肺腺癌增殖的影响。方法我们采用RT-PCR、Western-blot或免疫组化实验,分析ABCB1在肺腺癌细胞系、人肺腺癌组织以及GPRC5A基因敲除小鼠和野生型小鼠的气管上皮细胞和肺组织中的表达。采用细胞计数试剂盒-8(CCK-8)分析GPRC5A基因敲除小鼠气管上皮细胞对化疗药物的敏感性。采用皮下肿瘤形成实验探讨下调ABCB1表达是否可抑制体内肺腺癌增殖。采用免疫荧光和免疫沉淀实验研究GPRC5A和ABCB1之间潜在的调控关系。结果ABCB1在肺腺癌细胞系和人类肺腺癌组织中表达上调。GPRC5A基因敲除小鼠的气管上皮细胞及肺组织的ABCB1表达高于野生型小鼠。与GPRC5A野生型小鼠的气管上皮细胞相比,GPRC5A基因敲除小鼠的气管上皮细胞对塔立奇达和多柔比星更敏感。注射移植细胞28天后,接受ABCB1基因敲除细胞移植的GPRC5A-/-C57BL/6小鼠的肺肿瘤的体积和重量均明显低于野生型细胞移植小鼠(P=0.0043,P=0.0060)。此外,免疫荧光和免疫沉淀实验表明,GPRC5A通过直接结合方式调控ABCB1的表达。结论GPRC5A通过抑制ABCB1表达降低肺腺癌增殖。GPRC5A调节ABCB1表达的途径有待研究。
基金supported by the National Natural Science Foundation of China(No.30971244)
文摘Mitofusin2 （Mfn2） plays a pivotal role in the proliferation and apoptosis of vascular smooth muscle cells （VSMCs）. The purpose of this study was to investigate the effects of Mfn2 on the traffick- ing of intracellular cholesterol in the foam ceils derived from rat VSMCs （rVSMCs） and also to investigate the effects of Mfn2 on the expression of adenosine triphosphate-binding cassette subfamily A member 1 （ABCA1）, adenosine triphosphate-binding cassette subfamily G member 1 （ABCG1） and peroxisome proliferator-activated receptor gamma （PPARy）. The rVSMCs were co-cultured with oxi- dized low density lipoprotein （LDL, 80 ~tg/mL） to produce foam cells and cholesterol accumulation in cells. Before oxidized LDL treatment, different titers （20, 40 and 60 pfu/cell） of recombinant adenovirus containing Mfn2 gene （Adv-Mfn2） were added into the culture medium for 24 h to transfect the Mfn2 gene into the rVSMCs. Then the cells were harvested for analyses. The protein expression of Mfn2 was significantly higher in Adv-Mfn2-transfected group than in untransfected group （P〈0.05）, and the ex- pression levels significantly increased when the titer of Adv-Mfn2 increased （P〈0.05）. At 24 or 48 h af- ter oxidized LDL treatment, rVSMCs became irregular and their nuclei became larger, and their plasma abounded with red lipid droplets. However, the number of red lipid droplets was significantly decreased in Adv-Mfn2-transfected group as compared with untransfected group. At 48 h after oxidized LDL treatment, the intracellular cholesterol in rVSMCs was significantly increased （P〈0.05）, but it was sig- nificantly decreased in Adv-Mfn2-transfected group as compared with untransfected group （P〈0.05）, and it also significantly decreased when the titer of Adv-Mfn2 increased （P〈0.05）. The mRNA and pro- tein expression levels of ABCA1 and ABCG1 were significantly increased in Adv-Mfn2-transfected group as compared with untransfected group （P〈0.05）. Though the mRNA and protein expression levels of PPARy was not significantly increased （P〉0.05）, the phosporylation levels of PPARy were signifi- cantly decreased in Adv-Mfn2-transfected group as compared with untransfected group （P〈0.05）. These results suggest that the transfection of Adv-Mfn2 can significantly reduce intracellular cholesterol in oxidized LDL-induced rVSMCs possibly by decreasing PPAR＇/phosporylation and then increasing pro- tein expression levels of ABCAI and ABCG1, which may be helpful to suppress the formation of foam cells.
基金Cultivating funding of the First Affiliated Hospital of Chongqing Medical University(PYJJ2017-33)
文摘Harlequin ichthyosis is a severe autosomal recessive skin disorder.Most deaths occur within the first few days after birth,and the survivors still have severe chronic skin disease throughout their lives.Almost all cases were associated with a pathogenic variant of adenosine triphosphate binding cassette transporter,subfamily A,member 12(ABCA12)gene.We described a case of HI diagnosed by ultrasound examination during the second-trimester and genetic diagnosis reveal two novel heterozygous ABCA12 mutations c.2563-2570delinsGGCAATT,p.(Leu855Glyfs*13),and c.6116delT,p.(Met2039Argfs*8)by the next-generation DNA sequencing,which further enriched our understanding of the pathogenic variation of ABCA12 gene.
