The detection and analysis of circulating tumor cells （CTCs） from patients＇ blood is important to assess tumor status; however, it remains a challenge. In the present study, we developed a programmable DNA-responsi...The detection and analysis of circulating tumor cells （CTCs） from patients＇ blood is important to assess tumor status; however, it remains a challenge. In the present study, we developed a programmable DNA-responsive microchip for the highly efficient capture and nondestructive release of CTCs via nucleic acid hybridization. Transparent and patternable substrates with hierarchical architectures were integrated into the microchip with herringbone grooves, resulting in greatly enhanced cell-surface interaction via herringbone micromixers, more binding sites, and better matched topographical interactions. In combination with a high-affinity aptamer, target cancer cells were specifically and efficiently captured on the chip. Captured cancer cells were gently released from the chip under physiological conditions using toehold-mediated strand displacement, without any destructive factors for cells or substrates. More importantly, aptamercontaining DNA sequences on the surface of the retrieved cancer cells could be further amplified by polymerase chain reaction （PCR）, facilitating the detection of cell surface biomarkers and characterization of the CTCs. Furthermore, this system was extensively applied to the capture and release of CTCs from patients＇ blood samples, demonstrating a promising high-performance platform for CTC enrichment, release, and characterization.展开更多
目的探讨DNA损伤应答蛋白1(regulated in development and DNA damage responses-1,REDD1)在幽门螺杆菌(Helicobacter pylori,H.pylori)感染中的表达及调控机制。方法建立H.pylori感染C57小鼠及胃上皮细胞模型,运用实时荧光定量PCR、免...目的探讨DNA损伤应答蛋白1(regulated in development and DNA damage responses-1,REDD1)在幽门螺杆菌(Helicobacter pylori,H.pylori)感染中的表达及调控机制。方法建立H.pylori感染C57小鼠及胃上皮细胞模型,运用实时荧光定量PCR、免疫组织化学染色和Western blot检测REDD1 mRNA和蛋白的表达;并在细胞模型中采用信号通路抑制剂的方法探讨H.pylori感染诱导REDD1上调的机制。结果相对于未感染组,H.pylori感染小鼠胃黏膜中的REDD1水平显著增高;而相对于野生型(Wild Type,WT)全毒株,敲除cagA基因后,H.pylori感染诱导REDD1上调的能力则显著下降(P<0.05);H.pylori感染可诱导胃上皮细胞AGS REDD1表达上调,并具有时间、感染菌量以及cagA依赖性(P<0.05);P38/MAPK信号通路阻断可显著抑制H.pylori感染诱导的REDD1上调表达(P<0.05)。结论H.pylori依赖磷酸化的cagA蛋白激活MAPKp38通路诱导REDD1表达增高。展开更多
基金This work was supported by the National Natural Science Foundation of China （NSFC） （Nos. 21432008, 91413109 and 21575110）. China Postdoctoral Innovative Talent Support Program of China （No. BX201700176）.
文摘The detection and analysis of circulating tumor cells （CTCs） from patients＇ blood is important to assess tumor status; however, it remains a challenge. In the present study, we developed a programmable DNA-responsive microchip for the highly efficient capture and nondestructive release of CTCs via nucleic acid hybridization. Transparent and patternable substrates with hierarchical architectures were integrated into the microchip with herringbone grooves, resulting in greatly enhanced cell-surface interaction via herringbone micromixers, more binding sites, and better matched topographical interactions. In combination with a high-affinity aptamer, target cancer cells were specifically and efficiently captured on the chip. Captured cancer cells were gently released from the chip under physiological conditions using toehold-mediated strand displacement, without any destructive factors for cells or substrates. More importantly, aptamercontaining DNA sequences on the surface of the retrieved cancer cells could be further amplified by polymerase chain reaction （PCR）, facilitating the detection of cell surface biomarkers and characterization of the CTCs. Furthermore, this system was extensively applied to the capture and release of CTCs from patients＇ blood samples, demonstrating a promising high-performance platform for CTC enrichment, release, and characterization.
文摘目的探讨DNA损伤应答蛋白1(regulated in development and DNA damage responses-1,REDD1)在幽门螺杆菌(Helicobacter pylori,H.pylori)感染中的表达及调控机制。方法建立H.pylori感染C57小鼠及胃上皮细胞模型,运用实时荧光定量PCR、免疫组织化学染色和Western blot检测REDD1 mRNA和蛋白的表达;并在细胞模型中采用信号通路抑制剂的方法探讨H.pylori感染诱导REDD1上调的机制。结果相对于未感染组,H.pylori感染小鼠胃黏膜中的REDD1水平显著增高;而相对于野生型(Wild Type,WT)全毒株,敲除cagA基因后,H.pylori感染诱导REDD1上调的能力则显著下降(P<0.05);H.pylori感染可诱导胃上皮细胞AGS REDD1表达上调,并具有时间、感染菌量以及cagA依赖性(P<0.05);P38/MAPK信号通路阻断可显著抑制H.pylori感染诱导的REDD1上调表达(P<0.05)。结论H.pylori依赖磷酸化的cagA蛋白激活MAPKp38通路诱导REDD1表达增高。
