目的探讨MNX1通过调控ATG7诱导细胞自噬介导鼻咽癌放疗抵抗的作用机制。方法采用人鼻咽癌抗辐射细胞系HONE-1-IR和辐射敏感细胞系HONE-1进行体外分析;检测细胞中MNX1的表达水平,比较自噬标志物LC3Ⅱ、ATG7和p62表达情况;并分析MNX1与ATG...目的探讨MNX1通过调控ATG7诱导细胞自噬介导鼻咽癌放疗抵抗的作用机制。方法采用人鼻咽癌抗辐射细胞系HONE-1-IR和辐射敏感细胞系HONE-1进行体外分析;检测细胞中MNX1的表达水平,比较自噬标志物LC3Ⅱ、ATG7和p62表达情况;并分析MNX1与ATG7调控细胞自噬的关系。结果与HONE-1细胞相比,HONE-1-IR细胞中MNX1 m RNA和蛋白水平均升高,LC3Ⅱ、ATG7和p62蛋白表达水平同样升高(P<0.05);下调MNX1抑制了自噬体的形成(P<0.05)。与阴性对照组相比,转染si MNX1的细胞增殖率和细胞活力明显降低(P<0.05);细胞集落形成率明显降低(P<0.05)。下调MNX1明显阻断了自噬体的形成,上调ATG7后,自噬体的抑制水平恢复到对照组的水平(P<0.05);在HONE-1-IR细胞中通过下调MNX1抑制了细胞的增殖和活力,而通过上调ATG7逆转了这种抑制(P<0.05)。结论MNX1通过上调ATG7调控细胞自噬参与放疗抵抗,通过敲低MNX1-ATG7轴可提高放疗抵抗细胞的敏感性,MNX1可作为增强放射敏感性的潜在治疗靶点。展开更多
The resistivity of Hg<sub>0.89</sub>Mn<sub>0.11</sub>Te has been measured by the superconducting quantum interference device magnetometer in the temperature range from 5 to 200 K under the appl...The resistivity of Hg<sub>0.89</sub>Mn<sub>0.11</sub>Te has been measured by the superconducting quantum interference device magnetometer in the temperature range from 5 to 200 K under the applied magnetic field of 1, 2, 4 and 6.5 Tesla, respectively, compared with that of no-magnetic field. The results show that the resistivity increases with increase applied magnetic field at higher temperature from 80 to 200 K, but decreases at lower temperature from 5 to 25 K. There exists a transitive range from 25 to 80 K, where the variation of the resistivity shows different tendencies depending on the strength of magnetic field. Maximum difference of resistivity under 6.5 Tesla from that without magnetic field in the temperature range from 30 to 200 K is only about 5 Ω·cm, but it increases up to 3 orders of magnitude at 5 K. The analysis shows that the variation of resistivity of Hg<sub>0.89</sub>Mn<sub>0.11</sub>Te under the magnetic field is the algebraic sum of the transverse direction magnetoresistance effect and the sp-d exchange interaction effect. TDRME plays major role in the high temperature range. However, with the decrease of temperature, the effect of sp-d EI on the resistivity gradually exceeds that of the transverse direction magnetoresistance effect through the transitive range, and becomes the dominant effect in the temperature range from 5 to 25 K, which leads to the dramatic decrease of resistivity.展开更多
文摘目的探讨MNX1通过调控ATG7诱导细胞自噬介导鼻咽癌放疗抵抗的作用机制。方法采用人鼻咽癌抗辐射细胞系HONE-1-IR和辐射敏感细胞系HONE-1进行体外分析;检测细胞中MNX1的表达水平,比较自噬标志物LC3Ⅱ、ATG7和p62表达情况;并分析MNX1与ATG7调控细胞自噬的关系。结果与HONE-1细胞相比,HONE-1-IR细胞中MNX1 m RNA和蛋白水平均升高,LC3Ⅱ、ATG7和p62蛋白表达水平同样升高(P<0.05);下调MNX1抑制了自噬体的形成(P<0.05)。与阴性对照组相比,转染si MNX1的细胞增殖率和细胞活力明显降低(P<0.05);细胞集落形成率明显降低(P<0.05)。下调MNX1明显阻断了自噬体的形成,上调ATG7后,自噬体的抑制水平恢复到对照组的水平(P<0.05);在HONE-1-IR细胞中通过下调MNX1抑制了细胞的增殖和活力,而通过上调ATG7逆转了这种抑制(P<0.05)。结论MNX1通过上调ATG7调控细胞自噬参与放疗抵抗,通过敲低MNX1-ATG7轴可提高放疗抵抗细胞的敏感性,MNX1可作为增强放射敏感性的潜在治疗靶点。
基金Supported by the National Natural Science Foundation of China(No.50336040)
文摘The resistivity of Hg<sub>0.89</sub>Mn<sub>0.11</sub>Te has been measured by the superconducting quantum interference device magnetometer in the temperature range from 5 to 200 K under the applied magnetic field of 1, 2, 4 and 6.5 Tesla, respectively, compared with that of no-magnetic field. The results show that the resistivity increases with increase applied magnetic field at higher temperature from 80 to 200 K, but decreases at lower temperature from 5 to 25 K. There exists a transitive range from 25 to 80 K, where the variation of the resistivity shows different tendencies depending on the strength of magnetic field. Maximum difference of resistivity under 6.5 Tesla from that without magnetic field in the temperature range from 30 to 200 K is only about 5 Ω·cm, but it increases up to 3 orders of magnitude at 5 K. The analysis shows that the variation of resistivity of Hg<sub>0.89</sub>Mn<sub>0.11</sub>Te under the magnetic field is the algebraic sum of the transverse direction magnetoresistance effect and the sp-d exchange interaction effect. TDRME plays major role in the high temperature range. However, with the decrease of temperature, the effect of sp-d EI on the resistivity gradually exceeds that of the transverse direction magnetoresistance effect through the transitive range, and becomes the dominant effect in the temperature range from 5 to 25 K, which leads to the dramatic decrease of resistivity.
