Increasing attention is focused on the down-regulation of miRNAs in cancer process. Nuclear receptor subfamily 2 （NR2F2, also known as COUP-TFU） is involved in the development of many types of cancers, but its role ...Increasing attention is focused on the down-regulation of miRNAs in cancer process. Nuclear receptor subfamily 2 （NR2F2, also known as COUP-TFU） is involved in the development of many types of cancers, but its role in gastric cancer remains elusive. In this experiment, oncomine and Kaplan-meier database revealed that NR2F2 was up-regulated in gastric cancer and that the high NR2F2 expression contributed to poor survival. MicroRNA-2Tb was targeted and down-regulated by NR2F2 in human gastric cancer tissues and cells. The ectopic expression of miR-27b inhibited gastric cancer cell proliferation and tumor growth in vitro and in vivo. Assays suggested that the overexpression of miR-27b could promote MGC-803 cells＇ migration and invasion and retard their metastasis to the liver. In addition, down-regulation of miR-27b enhanced GES-1 cells＇ proliferation and metastasis in vitro. These findings reveal that miR-27b is a tumor suppressor in gastric cancer and a biomarker for improving patients＇ survival.展开更多
Drug-metabolizing enzymes, transporters, and nuclear receptors are essential for the absorption, distribution, metabolism, and excretion(ADME) of drugs and xenobiotics. MicroRNAs participate in the regulation of ADME ...Drug-metabolizing enzymes, transporters, and nuclear receptors are essential for the absorption, distribution, metabolism, and excretion(ADME) of drugs and xenobiotics. MicroRNAs participate in the regulation of ADME gene expression via imperfect complementary Watson–Crick base pairings with target transcripts. We have previously reported that Cytochrome P450 3A4(CYP3A4) and ATP-binding cassette sub-family G member 2(ABCG2) are regulated by miR-27b-3p and miR-328-3p,respectively. Here we employed our newly established RNA bioengineering technology to produce bioengineered RNA agents(BERA), namely BERA/miR-27b-3p and BERA/miR-328-3p, via fermentation. When introduced into human cells, BERA/miR-27b-3p and BERA/miR-328-3p were selectively processed to target miRNAs and thus knock down CYP3A4 and ABCG2 mRNA and their protein levels,respectively, as compared to cells treated with vehicle or control RNA. Consequently, BERA/miR-27b-3p led to a lower midazolam 10-hydroxylase activity, indicating the reduction of CYP3A4 activity. Likewise,BERA/miR-328-3p treatment elevated the intracellular accumulation of anticancer drug mitoxantrone, a classic substrate of ABCG2, hence sensitized the cells to chemotherapy. The results indicate that biologic miRNA agents made by RNA biotechnology may be applied to research on miRNA functions in the regulation of drug metabolism and disposition that could provide insights into the development of more effective therapies.展开更多
目的:通过建立高脂饮食单纯营养性肥胖大鼠模型,结合脂肪组织中脂肪酸结合蛋白AFABP1、脂肪酸转运蛋白FATP4和胆固醇反转物ABCA1的表达水平变化,从脂类物质结合和转运的角度探讨低氧训练对miRNA-27b/PPARγ调节通路及其下游相关靶基因...目的:通过建立高脂饮食单纯营养性肥胖大鼠模型,结合脂肪组织中脂肪酸结合蛋白AFABP1、脂肪酸转运蛋白FATP4和胆固醇反转物ABCA1的表达水平变化,从脂类物质结合和转运的角度探讨低氧训练对miRNA-27b/PPARγ调节通路及其下游相关靶基因表达的影响。方法:SD大鼠肥胖模型验证成功后,随机分为常氧安静组(NC)、常氧训练组(NT)、低氧安静组(HC)和低氧训练组(HT)。NT和HT组分别以20 m/min、25 m/min进行水平跑台训练,持续训练4周,1 h/天,6天/周;NC和HC组不运动;低氧氧浓度为13.6%(相当于海拔3 500 m)。4周后取血清进行血脂测试,肾周脂肪采用q RT-PCR进行miRNA-27b、PPARγ、AFABP1、FATP4、ABCA1基因表达检测。结果:1)HT、HC和NT组大鼠体重低于NC组(P<0.01),NT组脂肪重量低于NC组(P<0.05),HT组脂肪重低于NC、HC组(P<0.01);2)HT、HC组的TC值低于NC组(P<0.05),HC、HT组的TG值高于NT组(P<0.01),HT、HC组的HDLC值低于NC、NT组(P<0.05);3)HT组的miRNA-27b表达较NC、NT和HC组下调(P<0.01);4)HT组的PPARγm RNA表达较NC、HC组上调(P<0.01);5)NT组的FABP1 m RNA表达较NC组上调(P<0.01),HC组较NC组下调(P<0.01),HT组较NC、HC组上调(P<0.01),HT组较NT组下调(P<0.01),HT组的FATP4 m RNA较NC组上调(P<0.01),HT、HC组的ABCA1 m RNA表达较NC、NT组下调(P<0.01)。结论:1)低氧训练较常氧训练和单纯低氧暴露降低肥胖大鼠体重和脂肪重量更有效;2)低氧训练通过抑制脂肪组织miRNA-27表达,上调PPARγ表达,影响下游靶基因AFABP1和FATP4的表达,促进脂肪酸的结合与转运,但却抑制ABCA1表达,引起HDL-C水平下降。展开更多
文摘Increasing attention is focused on the down-regulation of miRNAs in cancer process. Nuclear receptor subfamily 2 （NR2F2, also known as COUP-TFU） is involved in the development of many types of cancers, but its role in gastric cancer remains elusive. In this experiment, oncomine and Kaplan-meier database revealed that NR2F2 was up-regulated in gastric cancer and that the high NR2F2 expression contributed to poor survival. MicroRNA-2Tb was targeted and down-regulated by NR2F2 in human gastric cancer tissues and cells. The ectopic expression of miR-27b inhibited gastric cancer cell proliferation and tumor growth in vitro and in vivo. Assays suggested that the overexpression of miR-27b could promote MGC-803 cells＇ migration and invasion and retard their metastasis to the liver. In addition, down-regulation of miR-27b enhanced GES-1 cells＇ proliferation and metastasis in vitro. These findings reveal that miR-27b is a tumor suppressor in gastric cancer and a biomarker for improving patients＇ survival.
基金supported in part by the National Institutes of Health [Grant No. R01GM113888 (Aiming Yu), USA]supported by Visiting Scholar Programs from China Scholarship Council (201608440507, USA) Guangzhou Medical University+2 种基金National Natural Science Foundation of China (81603191, China)Natural Science Foundation of Guangdong Province (2015A030310153, China)supported by the 3102018zy053 from Fundamental Research Funds for the Central Universities (China)funded by the UC Davis Comprehensive Cancer Center Support Grant (CCSG) awarded by the National Cancer Institute (Grant No. P30CA093373, USA)
文摘Drug-metabolizing enzymes, transporters, and nuclear receptors are essential for the absorption, distribution, metabolism, and excretion(ADME) of drugs and xenobiotics. MicroRNAs participate in the regulation of ADME gene expression via imperfect complementary Watson–Crick base pairings with target transcripts. We have previously reported that Cytochrome P450 3A4(CYP3A4) and ATP-binding cassette sub-family G member 2(ABCG2) are regulated by miR-27b-3p and miR-328-3p,respectively. Here we employed our newly established RNA bioengineering technology to produce bioengineered RNA agents(BERA), namely BERA/miR-27b-3p and BERA/miR-328-3p, via fermentation. When introduced into human cells, BERA/miR-27b-3p and BERA/miR-328-3p were selectively processed to target miRNAs and thus knock down CYP3A4 and ABCG2 mRNA and their protein levels,respectively, as compared to cells treated with vehicle or control RNA. Consequently, BERA/miR-27b-3p led to a lower midazolam 10-hydroxylase activity, indicating the reduction of CYP3A4 activity. Likewise,BERA/miR-328-3p treatment elevated the intracellular accumulation of anticancer drug mitoxantrone, a classic substrate of ABCG2, hence sensitized the cells to chemotherapy. The results indicate that biologic miRNA agents made by RNA biotechnology may be applied to research on miRNA functions in the regulation of drug metabolism and disposition that could provide insights into the development of more effective therapies.
文摘目的:通过建立高脂饮食单纯营养性肥胖大鼠模型,结合脂肪组织中脂肪酸结合蛋白AFABP1、脂肪酸转运蛋白FATP4和胆固醇反转物ABCA1的表达水平变化,从脂类物质结合和转运的角度探讨低氧训练对miRNA-27b/PPARγ调节通路及其下游相关靶基因表达的影响。方法:SD大鼠肥胖模型验证成功后,随机分为常氧安静组(NC)、常氧训练组(NT)、低氧安静组(HC)和低氧训练组(HT)。NT和HT组分别以20 m/min、25 m/min进行水平跑台训练,持续训练4周,1 h/天,6天/周;NC和HC组不运动;低氧氧浓度为13.6%(相当于海拔3 500 m)。4周后取血清进行血脂测试,肾周脂肪采用q RT-PCR进行miRNA-27b、PPARγ、AFABP1、FATP4、ABCA1基因表达检测。结果:1)HT、HC和NT组大鼠体重低于NC组(P<0.01),NT组脂肪重量低于NC组(P<0.05),HT组脂肪重低于NC、HC组(P<0.01);2)HT、HC组的TC值低于NC组(P<0.05),HC、HT组的TG值高于NT组(P<0.01),HT、HC组的HDLC值低于NC、NT组(P<0.05);3)HT组的miRNA-27b表达较NC、NT和HC组下调(P<0.01);4)HT组的PPARγm RNA表达较NC、HC组上调(P<0.01);5)NT组的FABP1 m RNA表达较NC组上调(P<0.01),HC组较NC组下调(P<0.01),HT组较NC、HC组上调(P<0.01),HT组较NT组下调(P<0.01),HT组的FATP4 m RNA较NC组上调(P<0.01),HT、HC组的ABCA1 m RNA表达较NC、NT组下调(P<0.01)。结论:1)低氧训练较常氧训练和单纯低氧暴露降低肥胖大鼠体重和脂肪重量更有效;2)低氧训练通过抑制脂肪组织miRNA-27表达,上调PPARγ表达,影响下游靶基因AFABP1和FATP4的表达,促进脂肪酸的结合与转运,但却抑制ABCA1表达,引起HDL-C水平下降。
文摘目的探讨mi R-27b在雌激素受体(ER)阳性的乳腺癌细胞上皮间质转化及他莫昔芬耐药中的调控机制。方法通过反转录实时定量PCR测定mi R-27b的表达。用双荧光素酶报告和蛋白质印迹实验验证mi R-27b对HMGB3的靶向调控作用。在他莫昔芬敏感(Tam S)或耐药(Tam R)的MCF-7细胞中过表达mi R-27b或敲减HMGB3后测定细胞活力,分析上皮和间质标志物的表达,检测细胞侵袭力。结果 Tam R MCF-7细胞中mi R-27b的水平约为Tam S MCF-7细胞的20%。过表达mi R-27b增加了4-羟基他莫昔芬(4-OHT)对Tam R MCF-7细胞的活力抑制。Tam S与Tam R细胞在mi R-27b过表达后,穿膜细胞数目均明显减少。在Tam R MCF-7细胞中,转染mi R-27b mimics增加了约3倍的E-cadherin表达,同时也降低了约70%的N-cadherin表达。mi R-27b可以结合预测的HMGB3 3′非翻译区(UTR)结合位点并降低HMGB3在蛋白水平的表达。HMGB3敲减和mi R-27b过表达具有类似的生物学功能。结论 mi R-27b可以通过抑制HMGB3的表达抑制乳腺癌细胞上皮间质转化并增强乳腺癌细胞他莫昔芬敏感性。
