In this study, we reported the effect of the ATP binding site competitive inhibitor Torin1 on activated α2-macroglobulin (α2M*)-induced cell proliferation and activation of mTORC1 and mTORC2 signaling in prostate ca...In this study, we reported the effect of the ATP binding site competitive inhibitor Torin1 on activated α2-macroglobulin (α2M*)-induced cell proliferation and activation of mTORC1 and mTORC2 signaling in prostate cancer cells. Torin1 significantly inhibited α2M*-induced cellproliferation as measured by protein and DNA synthesis. Translational activity, a major cellular response in malignant cells,is coordinately regulated by the mTORC1-S6-kinaseand mTORC1-4EBP1 axes. Torin1 significantly inhibited α2M*- and insulin-induced activation of mTORC1 as determined by phosphorylation of S6-kinaseat Thr389 and 4EBP1 at Thr37/46 compared to untreated cells employing Raptor immunoprecipitates. Torin1 also significantly inhibited α2M*- and insulin-induced upregulation of p-AktT308 and p-AktS473 in prostate cancer cells. The effect was comparable to that of insulin employed as a positive control. Finally, Torin1 inhibited α2M*- and insulin-induced activation of mTORC2 kinase assayas measured by phosphorylation of Akt at Ser473 inRictor immunoprecipitates of prostate cancer cells.展开更多
目的观察高糖条件下肾小管上皮细胞第10号染色体缺失的磷酸酶和张力蛋白同源基因(PTEN)蛋白的表达变化,探讨其在肾小管纤维化病变中的作用及可能机制。方法体外培养大鼠肾小管上皮细胞株(NRK52E),随机分为对照组和高糖组,每组分别设2、1...目的观察高糖条件下肾小管上皮细胞第10号染色体缺失的磷酸酶和张力蛋白同源基因(PTEN)蛋白的表达变化,探讨其在肾小管纤维化病变中的作用及可能机制。方法体外培养大鼠肾小管上皮细胞株(NRK52E),随机分为对照组和高糖组,每组分别设2、12、24、48 h 4个时间点进行动态观察;采用免疫荧光细胞化学染色检测E-钙黏素(E-cadherin)和α-平滑肌肌动蛋白(α-SMA)表达变化,Western blotting检测各组PTEN、磷酸化蛋白激酶B[p-Akt1(Ser473)]、E-caderin和α-SMA蛋白表达变化。结果与对照组比较,高糖组培养24、48 h时,PTEN、E-caherin蛋白表达量[分别为(1.15±0.13)、(1.10±0.13)和(1.23±0.11)、(1.22±0.11)]均减少(均P<0.05),而p-Akt1(Ser473)、α-SMA蛋白表达量[分别为(1.53±0.13)、(1.60±0.13)和(1.86±0.10)、(1.91±0.10)]均增多(均P<0.05);PTEN与E-cadherin蛋白表达量呈正相关(r=0.58,P<0.05),与α-SMA蛋白表达量呈负相关(r=-0.61,P<0.05)。结论高糖培养的肾小管上皮细胞中PTEN蛋白表达明显减少,可能通过PI3K/Akt信号通路参与了肾小管纤维化病变的发生发展过程。展开更多
文摘In this study, we reported the effect of the ATP binding site competitive inhibitor Torin1 on activated α2-macroglobulin (α2M*)-induced cell proliferation and activation of mTORC1 and mTORC2 signaling in prostate cancer cells. Torin1 significantly inhibited α2M*-induced cellproliferation as measured by protein and DNA synthesis. Translational activity, a major cellular response in malignant cells,is coordinately regulated by the mTORC1-S6-kinaseand mTORC1-4EBP1 axes. Torin1 significantly inhibited α2M*- and insulin-induced activation of mTORC1 as determined by phosphorylation of S6-kinaseat Thr389 and 4EBP1 at Thr37/46 compared to untreated cells employing Raptor immunoprecipitates. Torin1 also significantly inhibited α2M*- and insulin-induced upregulation of p-AktT308 and p-AktS473 in prostate cancer cells. The effect was comparable to that of insulin employed as a positive control. Finally, Torin1 inhibited α2M*- and insulin-induced activation of mTORC2 kinase assayas measured by phosphorylation of Akt at Ser473 inRictor immunoprecipitates of prostate cancer cells.
文摘目的观察高糖条件下肾小管上皮细胞第10号染色体缺失的磷酸酶和张力蛋白同源基因(PTEN)蛋白的表达变化,探讨其在肾小管纤维化病变中的作用及可能机制。方法体外培养大鼠肾小管上皮细胞株(NRK52E),随机分为对照组和高糖组,每组分别设2、12、24、48 h 4个时间点进行动态观察;采用免疫荧光细胞化学染色检测E-钙黏素(E-cadherin)和α-平滑肌肌动蛋白(α-SMA)表达变化,Western blotting检测各组PTEN、磷酸化蛋白激酶B[p-Akt1(Ser473)]、E-caderin和α-SMA蛋白表达变化。结果与对照组比较,高糖组培养24、48 h时,PTEN、E-caherin蛋白表达量[分别为(1.15±0.13)、(1.10±0.13)和(1.23±0.11)、(1.22±0.11)]均减少(均P<0.05),而p-Akt1(Ser473)、α-SMA蛋白表达量[分别为(1.53±0.13)、(1.60±0.13)和(1.86±0.10)、(1.91±0.10)]均增多(均P<0.05);PTEN与E-cadherin蛋白表达量呈正相关(r=0.58,P<0.05),与α-SMA蛋白表达量呈负相关(r=-0.61,P<0.05)。结论高糖培养的肾小管上皮细胞中PTEN蛋白表达明显减少,可能通过PI3K/Akt信号通路参与了肾小管纤维化病变的发生发展过程。
