CARP-1: A Potential Therapeutic Agent for Breast Cancer

开发新的和改进的三阴性乳腺癌(TNBC)治疗策略是迫切的 由于TNBC的分子复杂性以及与治疗相关的副作用和出现的 耐药性往往会限制现有疗法的有效性。CARP-1/CCAR1是一种普遍存在的磷酸化蛋白 可通过多种机制诱导细胞增殖和凋亡。CARP-1转导化疗 (阿霉素、依托泊苷或易瑞沙)依赖的抑制信号，并共同激活阿霉素(ADR)诱导的 P53。CALP-1还共同激活细胞周期调节后期促进复合体(APC/C)E3泛素连接酶 和类固醇/甲状腺受体。在这里，我们报道了CARP-1与ERK相互作用，并与NEMO(NF-B)结合 必需调节剂；核因子-B激活激酶IKK亚单位)。我们的初步研究和发表的研究揭示了 阿霉素诱导CARP-1苏氨酸627磷酸化、ERK激活和典型的NF-B途径 涉及Nemo-carp-1结合。重要的是，抑制Nemo-Carp-1结合会降低NF-B的活性 (通过p65/relA的磷酸化)，但不被肿瘤坏死因子α、白介素2或表皮生长因子所抑制。此外，SNI-1，a Nemo-carp-1结合的新型SMI，增强ADR或顺铂对TNBC细胞的抑制，降低 基因毒性应激(阿霉素或顺铂)诱导促炎细胞因子肿瘤坏死因子、α和白介素8。SNI-1增强TNBC 阿霉素和顺铂对4T1同基因肿瘤模型体内生长的抑制作用。 假设：DNA损伤诱导药物(ADR、顺铂)激活CARP-1介导的经典性NF-B和 Erk小路。这一假设基本原理包括我们的初步研究和已发表的研究，这些研究表明 通过破坏Nemo-Carp-1结合抑制治疗诱导的规范的NF-B激活增强 ADR和顺铂的体内外疗效。此外，ADR还可诱导CARP-1的磷酸化， 由于基因毒性治疗也激活ERK，靶向与ERK抑制剂结合的Nemo-carp-1 将导致ADR或顺铂对肿瘤的更大抑制。因此，靶向CARP-1/NEMO结合可以 允许我们克服TNBCs的化疗耐药性，而不影响由NF-B诱导的其他中枢功能 通过肿瘤坏死因子α、白介素2和/或表皮生长因子信号转导宿主组织的动态平衡。我们将进行以下三项工作 旨在检验我们的假设。 目的：探讨CARP-1在遗传毒性化疗诱导的典型的NF-B生存通路中的作用。SNI-1 抑制治疗诱导的NEMO磷酸化。我们将阐明SNI-1是如何抑制DNA损伤的， NEMO磷酸化和典型的NF-B途径。 目的：探讨CARP-1与ERKs相互作用的机制(S)。我们将确定如何确定目标 ERKS与SNI-1联合使用可提高基因毒性化疗的疗效。 目的3：证明通过水溶性靶向CARP-1/NEMO依赖的规范的、核转录因子-B信号转导 SNI-1单独或与目前正在临床试验/使用的治疗药物靶向ERK将导致 体内基因毒性化疗对TNBC肿瘤的杀伤作用 对退伍军人医疗保健的潜在影响：拟议的研究将产生有价值的分子知识 基因毒性化疗药物(ADR和顺铂)有效治疗白血病的作用机制 TNBCs及其耐药同龄人。我们发现的SNI-1及其对提高慢性粒细胞白血病疗效的潜力 克服治疗诱导耐药性的TNBC疗法将产生翻译影响，并有望 促进制定新的和有效的战略，以打击将受益于乳腺癌的艰难治疗 退伍军人管理局女性工作人员，为退伍军人医疗保健做出贡献，并推动退伍军人管理局的使命。

Development of new and improved strategies for triple-negative breast cancer (TNBC) treatment is urgently needed since molecular complexity of TNBC together with therapy-associated side effects and emergence of drug-resistance often limit effectiveness of current therapies. CARP-1/CCAR1 is a ubiquitous, phospho-protein that can induce proliferation and apoptosis through multiple mechanisms. CARP-1 transduces chemotherapy (adriamycin, etoposide, or Iressa)-dependent inhibitory signaling, and co-activates Adriamycin (ADR)-induced p53. CARP-1 also co-activates cell-cycle regulatory anaphase-promoting complex (APC/C) E3 ubiquitin ligase and steroid/thyroid receptors. Here we report that CARP-1 interacts with ERKs, and binds with NEMO (NF-B Essential Modulator; NF-B-activating kinase IKK subunit ). Our preliminary and published studies revealed that ADR induced CARP-1 threonine627 phosphorylation, ERK activation, and canonical NF-B pathway that involved NEMO-CARP-1 binding. Importantly, inhibition of NEMO-CARP-1 binding diminishes NF-B activation (noted by phosphorylation of p65/RelA) by ADR but not by TNFα, interleukin (IL)2, or EGF. Further, SNI-1, a novel SMI of NEMO-CARP-1 binding, enhances ADR or Cisplatin inhibition of TNBC cells, diminishes levels of genotoxic stress (ADR or Cisplatin)-induced pro-inflammatory cytokines TNFα and IL8. SNI-1 enhances TNBC growth suppression by ADR or Cisplatin in vivo in 4T1 syngeneic tumor model. Hypothesis: DNA Damage-inducing drugs (ADR, Cisplatin) activate CARP-1-mediated canonical NF-B and ERK pathways. The rationale for this hypothesis include our preliminary and published studies that indicate inhibition of therapy-induced, canonical NF-B activation by disruption of NEMO-CARP-1 binding enhances efficacy of ADR and Cisplatin in vitro and in vivo. Moreover, ADR also induces CARP-1 phosphorylation and, since genotoxic therapy also activates ERKs, targeting of NEMO-CARP-1 binding together with ERK inhibitors will result in greater tumor suppression by ADR or Cisplatin. Thus, targeting of CARP-1/NEMO binding could permit us to overcome chemo-resistance in TNBCs without affecting other central functions of NF-B induced by TNFα, IL2, and/or EGF signaling necessary for host tissue homeostasis. We will conduct following three aims to test our hypothesis. Aim 1: To define role of CARP-1 in genotoxic chemotherapy-induced canonical NF-B survival pathway. SNI-1 inhibits therapy-induced NEMO phosphorylation. We will elucidate how SNI-1 inhibits DNA damage-induced, NEMO phosphorylation and canonical NF-B pathway. Aim 2: To investigate mechanism(s) by which CARP-1 interacts with ERKs. We will determine how targeting of ERKs in combination with SNI-1 enhances efficacy of genotoxic chemotherapy. Aim 3: To demonstrate targeting of CARP-1/NEMO-dependent canonical, NF-B signaling by water-soluble SNI-1 alone or coupled with targeting of ERKs by therapeutics currently in clinical trials/use, will result in superior TNBC tumor kill by genotoxic chemotherapy in vivo. Potential Impact on Veterans Health Care: The proposed studies will yield valuable knowledge of molecular mechanisms of action of genotoxic chemotherapies (ADR and Cisplatin) to permit effective treatment of TNBCs and their drug-resistant counterparts. Our discovery of SNI-1 and its potential to enhance efficacy of TNBC therapies to overcome therapy-induced resistance will have translational impact and are expected to facilitate development of novel and effective strategies to combat hard to treat breast cancers that will benefit female VA workforce, contribute to Veterans Health Care and further the VA mission.