Huun Johanna, Lønning Per Eystein, Knappskog Stian
Section of Oncology, Department of Clinical Science, University of Bergen, Bergen, Norway.
Department of Oncology, Haukeland University Hospital, Bergen, Norway.
Cell Death Discov. 2017 May 22;3:17026. doi: 10.1038/cddiscovery.2017.26. eCollection 2017.
Loss of and function have both been linked to poor response to DNA damaging drugs in breast cancer patients. We inactivated and/or by siRNA mediated knockdown in breast cancer cell lines varying with respect to ER/PgR and Her-2 status as well as and mutation status (MCF-7, T47D, HTB-122 and CRL2324) and determined effects on cell cycle arrest, apoptosis and senescence with or without concomitant treatment with doxorubicin. In T47D cells, we found the cell cycle phase distribution to be altered when inactivating (=0.0003) or and concomitantly (≤0.001). No similar changes were observed in MCF-7, HTB-122 or CRL2324 cells. While no significant change was observed for the CRL2324 cells upon doxorubicin treatment, MCF-7, T47D as well as HTB-122 cells responded to knockdown of and in concert, with a decrease in the fraction of cells in G1/G0-phase (=0.042, 0.021 and 0.027, respectively). Inactivation of and/or caused no change in induction of apoptosis. Upon doxorubicin treatment, inactivation of or separately caused no induction of apoptosis in MCF-7 and HTB-122 cells; however, concomitant inactivation leads to a slightly reduced activation of apoptosis. Interestingly, upon doxorubicin treatment, concomitant inactivation of and caused a decrease in senescence in MCF-7 cells (=0.027). Comparing the effects of concomitant knockdown on apoptosis and senescence, we observed a strong interaction (=0.001). We found concomitant inactivation of and to affect various routes of response to doxorubicin treatment in breast cancer cells.
和功能的丧失均与乳腺癌患者对DNA损伤药物的不良反应有关。我们通过siRNA介导的敲低技术，在雌激素受体/孕激素受体（ER/PgR）、人表皮生长因子受体2（Her-2）状态以及和突变状态各不相同的乳腺癌细胞系（MCF-7、T47D、HTB-122和CRL2324）中使和/或失活，并确定了在有或没有阿霉素联合治疗的情况下对细胞周期停滞、凋亡和衰老的影响。在T47D细胞中，我们发现当使失活时（P = 0.0003）或同时使和失活时（P≤0.001），细胞周期阶段分布会发生改变。在MCF-7、HTB-122或CRL2324细胞中未观察到类似变化。虽然在阿霉素治疗后CRL2324细胞未观察到显著变化，但MCF-7、T47D以及HTB-122细胞在和同时敲低时会产生反应，G1/G0期细胞比例下降（分别为P = 0.042、0.021和0.027）。和/或的失活未引起凋亡诱导的变化。在阿霉素治疗后，单独使或失活在MCF-7和HTB-122细胞中未诱导凋亡；然而，同时失活会导致凋亡激活略有降低。有趣的是，在阿霉素治疗后，和同时失活导致MCF-7细胞衰老减少（P = 0.027）。比较同时敲低对凋亡和衰老的影响，我们观察到强烈的相互作用（P = 0.001）。我们发现和**同时失活会影响乳腺癌细胞对阿霉素治疗的各种反应途径。
