Bai Fang, Morcos Faruck, Sohn Yang-Sung, Darash-Yahana Merav, Rezende Celso O, Lipper Colin H, Paddock Mark L, Song Luhua, Luo Yuting, Holt Sarah H, Tamir Sagi, Theodorakis Emmanuel A, Jennings Patricia A, Onuchic José N, Mittler Ron, Nechushtai Rachel
Center for Theoretical Biological Physics and Department of Physics, Rice University, Houston, TX 77005;
The Alexander Silberman Institute of Life Science, Hebrew University of Jerusalem, Edmond J. Safra Campus at Givat Ram, Jerusalem 91904, Israel;
Proc Natl Acad Sci U S A. 2015 Mar 24;112(12):3698-703. doi: 10.1073/pnas.1502960112. Epub 2015 Mar 11.
Identification of novel drug targets and chemotherapeutic agents is a high priority in the fight against cancer. Here, we report that MAD-28, a designed cluvenone (CLV) derivative, binds to and destabilizes two members of a unique class of mitochondrial and endoplasmic reticulum (ER) 2Fe-2S proteins, mitoNEET (mNT) and nutrient-deprivation autophagy factor-1 (NAF-1), recently implicated in cancer cell proliferation. Docking analysis of MAD-28 to mNT/NAF-1 revealed that in contrast to CLV, which formed a hydrogen bond network that stabilized the 2Fe-2S clusters of these proteins, MAD-28 broke the coordinative bond between the His ligand and the cluster's Fe of mNT/NAF-1. Analysis of MAD-28 performed with control (Michigan Cancer Foundation; MCF-10A) and malignant (M.D. Anderson-metastatic breast; MDA-MB-231 or MCF-7) human epithelial breast cells revealed that MAD-28 had a high specificity in the selective killing of cancer cells, without any apparent effects on normal breast cells. MAD-28 was found to target the mitochondria of cancer cells and displayed a surprising similarity in its effects to the effects of mNT/NAF-1 shRNA suppression in cancer cells, causing a decrease in respiration and mitochondrial membrane potential, as well as an increase in mitochondrial iron content and glycolysis. As expected, if the NEET proteins are targets of MAD-28, cancer cells with suppressed levels of NAF-1 or mNT were less susceptible to the drug. Taken together, our results suggest that NEET proteins are a novel class of drug targets in the chemotherapeutic treatment of breast cancer, and that MAD-28 can now be used as a template for rational drug design for NEET Fe-S cluster-destabilizing anticancer drugs.
识别新型药物靶点和化疗药物是抗癌斗争中的重中之重。在此，我们报告一种设计合成的克鲁维酮（CLV）衍生物MAD - 28，它能结合并破坏一类独特的线粒体和内质网（ER）2Fe - 2S蛋白中的两个成员，即线粒体神经铁蛋白（mNT）和营养剥夺自噬因子1（NAF - 1），这两种蛋白最近被发现与癌细胞增殖有关。MAD - 28与mNT/NAF - 1的对接分析表明，与形成氢键网络稳定这些蛋白的2Fe - 2S簇的CLV不同，MAD - 28破坏了mNT/NAF - 1中组氨酸配体与簇中铁之间的配位键。对对照（密歇根癌症基金会；MCF - 10A）和恶性（MD安德森转移性乳腺癌；MDA - MB - 231或MCF - 7）人乳腺上皮细胞进行的MAD - 28分析显示，MAD - 28在选择性杀死癌细胞方面具有高度特异性，对正常乳腺细胞没有明显影响。发现MAD - 28靶向癌细胞的线粒体，并且在其作用方面与癌细胞中mNT/NAF - 1短发夹RNA（shRNA）抑制的作用表现出惊人的相似性，导致呼吸作用和线粒体膜电位降低，以及线粒体铁含量和糖酵解增加。正如预期的那样，如果NEET蛋白是MAD - 28的靶点，那么NAF - 1或mNT水平被抑制的癌细胞对该药物的敏感性较低。综上所述，我们的结果表明，NEET蛋白是乳腺癌化疗治疗中的一类新型药物靶点，并且MAD - 28现在可作为设计用于破坏NEET Fe - S簇的抗癌药物的合理药物设计模板。
