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目的:探究泛素结合酶10(UbcH10)对三阴性乳腺癌自噬的调节作用及其作用机制。方法:在人三阴性乳腺癌细胞系MDA-MB-231中，利用小干扰RNA(siRNA)进行瞬时转染低表达UBCH10基因，转染阴性对照siRNA的细胞作为阴性对照组，未经处理的细胞作为空白对照组。通过实时荧光定量反转录聚合酶链反应(RT-qPCR)和蛋白质印迹法(Western blot)检测转染后UbcH10的表达。MDA-MB-231细胞的增殖情况及单磷酸腺苷活化蛋白激酶(AMPK)/哺乳动物雷帕霉素靶蛋白(mTOR)通路相关蛋白的表达情况分别用细胞增殖试验(CCK-8)法及Western blot法检测。组间差异采用单因素方差分析和n t检验。n 结果:RT-qPCR和Western blot实验结果显示，转染后siUbcH10-1组和siUbcH10-2组UbcH10的mRNA和蛋白的表达水平低于阴性对照组，差异有统计学意义(0.182±0.138比0.917±0.031、0.127±0.136比0.917±0.031，n t＝9.191、9.876，n P<0.001)、(0.430±0.245比0.430±0.245、0.434±0.093比0.434±0.093，n t＝3.685、3.651，n P<0.05)，证明低表达细胞株构建成功。CCK-8结果显示，siUbcH10-1组和siUbcH10-2组细胞12、24、48 h的吸光度值均低于阴性对照组(0.160±0.004比0.211±0.004、0.155±0.003比0.211±0.004、0.246±0.006比0.286±0.012、0.202±0.004比0.286±0.012、0.308±0.007比0.432±0.004、0.308±0.013比0.432±0.004，n t＝14.965、16.423、4.649、9.629、13.737、13.756，n P<0.01)，差异有统计学意义。Western blot实验结果显示siUbcH10-1组和siUbcH10-2组微管相关蛋白1轻链3BⅡ(LC3BⅡ)/微管相关蛋白1轻链3BⅠ(LC3BⅠ)的比值及AMPK的磷酸化水平高于阴性对照组(4.294±0.812比2.552±0.002、4.554±0.216比2.552±0.002，n t＝4.033、4.633，n P<0.05)、(1.533±0.177比0.564±0.185、1.519±0.263比0.564±0.185，n t＝4.859、4.792，n P<0.05)，差异有统计学意义，mTOR的磷酸化水平低于阴性对照组(0.482±0.028比1.153±0.069、0.504±0.072比1.153±0.069，n t＝8.708、8.433，n P<0.05)，差异有统计学意义。n 结论:低表达UbcH10可通过抑制AMPK/mTOR信号通路来诱导三阴性乳腺癌细胞发生自噬。“,”Objective:To explore the regulation and mechanism of ubiquitin conjugating enzyme10 (UBCH10) on autophagy in triple-negative breast cancer (TNBC).Methods:Human TNBC cell line MDA-MB-231 was transfected by small interfering RNA (siRNA)-UBCH10 to knockdown UBCH10, cells transfected with negative control siRNA served as negative control group, and untreated cells served as blank control group.The expression level of UBCH10 was assessed by real-time quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR) and Western blotting. The proliferation of TNBC cells and the expression of adenosine 5′-monophosphate activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) pathway related proteins were detected by cell counting kit-8 (CCK-8) and Western blotting, respectively. One-way ANOVA and n t-test were used to compare difference between groups.n Results:The result of RT-qPCR and Western blotting showed that mRNA and protein expression of UbcH10 in siUbcH10-1 and siUbcH10-2 groups were significantly lower than negative control group (0.430±0.245 vs. 0.929±0.053, 0.434±0.093 vs. 0.929±0.053, n t=9.191, 9.876, n P<0.01), (0.430±0.245 vs. 0.430±0.245, 0.434±0.093 vs. 0.434±0.093,n t=3.685, 3.651, n P<0.05), which proved the successful construction of low-expressing cell lines. CCK-8 results showed that the absorbance (n A) at 12, 24 and 48 h in siUbcH10-1 and siUbcH10-2 groups was significantly lower than negative control group (0.160±0.004 vs. 0.211±0.004, 0.155±0.003 vs. 0.211±0.004, 0.246±0.006 vs. 0.286±0.012, 0.202±0.004 vs. 0.286±0.012, 0.308±0.007 vs. 0.432±0.004, 0.308±0.013 vs. 0.432±0.004, n t=14.965, 16.423, 4.649, 9.629, 13.737, 13.756, n P<0.01). Western blotting showed that the ratio of microtubule-associated protein 1 light chain 3BⅡ (LC3BⅡ)/microtubule-associated protein 1 light chain 3BⅠ (LC3BⅠ) and the expression level of p-AMPK in siUbcH10-1 and siUbcH10-2 groups were significantly higher than negative control group (4.294±0.812 vs. 2.552±0.002, 4.554±0.216 vs. 2.552±0.002,n t=4.033, 4.633, n P<0.05), (1.533±0.177 vs. 0.564±0.185, 1.519±0.263 vs. 0.564±0.185,n t=4.859, 4.792, n P<0.05), and the p-mTOR expression was significantly lower than negative control group (0.482±0.028 vs. 1.153±0.069, 0.504±0.072 vs. 1.153±0.069,n t=8.708, 8.433, n P<0.05).n Conclusion:Low-expression of UBCH10 may induce autophagy in TNBC cells by inhibiting the AMPK/mTOR signaling pathway.