The roles of TRAF2 and RIP1 in breast cancer cell survival

TRAF2 和 RIP1 在乳腺癌细胞存活中的作用

• 批准号: 10363270
• 负责人: HASEM HABELHAH
• 金额: $ 35.22万
• 依托单位: UNIVERSITY OF IOWA
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-05-15 至 2027-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10363270
• 关键词: AKT inhibition; Affect; Apoptosis; Bioinformatics; Biological Assay; Biological Markers; Biological Models; Breast Cancer Cell; Breast Cancer cell line; Breast Cancer therapy; Cancer Etiology; Cancer cell line; Cause of Death; Cell Line; Cell Survival; Cell physiology; Cellular Stress; Cessation of life; Clinical Trials; Data; Development; Diagnosis; Disease; Drug resistance; Exhibits; Genes; Goals; Growth; Growth Factor; Harvest; Histopathology; Homologous Gene; In Vitro; Malignant Neoplasms; Maps; Mediating; Modeling; Mus; Neoplasm Metastasis; PTEN gene; Pathway interactions; Patient-derived xenograft models of breast cancer; Peptides; Phosphorylation; Phosphorylation Site; Phosphotransferases; Play; Pre-Clinical Model; Prognosis; Protein-Serine-Threonine Kinases; Proto-Oncogene Proteins c-akt; RIPK1 gene; Recurrent disease; Reporting; Resistance; Resistance development; Role; Series; Signal Transduction; Small Interfering RNA; Solid Neoplasm; TBK1 gene; TNF gene; TRAF2 gene; Testing; Treatment Efficacy; Ubiquitination; Woman; Xenograft Model; Xenograft procedure; anticancer research; cancer cell; derepression; in vivo; inhibitor; kinase inhibitor; knock-down; malignant breast neoplasm; mortality; novel therapeutic intervention; overexpression; patient derived xenograft model; predictive marker; recruit; response; targeted treatment; tool; treatment response; tumor; tumor growth; tumor xenograft; ubiquitin-protein ligase

Breast cancer (BC) is the most frequently diagnosed malignancy and the second leading cause of cancer mortality in Western women. As is the case for most other solid tumors, metastasis and drug resistance are the main causes of death. In ~80% of BC cases, the PI3K-AKT pathway is aberrantly activated, due to the alterations in genes encoding the pathway components, such as Ras, Her2, PTEN, PIK3C and AKT. This pathway regulates multiple cellular processes to promote BC development, growth, metastasis, and drug resistance. Consequently, over 100 clinical trials are currently underway worldwide to evaluate the therapeutic efficacy of PI3K and AKT inhibitors in BC; however, initial data revealed that inhibition of this pathway is either not effective or often results in development of resistance and relapse of the disease. Thus, identification of additional targets and therapeutic combinations are urgently needed. We previously mapped TRAF2 phosphorylation sites and reported that TRAF2 Ser-11 phosphorylation enhances NF-κB activation to promote cancer cell survival under conditions of cellular stresses. Recently, we discovered that inhibition of AKT in BC cells leads to increased phosphorylation of TRAF2 by TBK1, and that inhibition of both AKT and TBK1 synergistically induces apoptosis in BC cell lines in vitro and significantly suppresses xenograft BC tumor growth in vivo. TBK1 and its close homologue IKKε are serine/threonine kinases overexpressed in 65-70% of BC and play critical roles in BC cell survival mainly by direct phosphorylation of TRAF2 at Ser-11. In cancer cells, TRAF2 constitutively recruits potent E3 ligases cIAP1 and cIAP2 (cIAPs) to RIP1 to catalyze its noncanonical ubiquitination, which is not only essential for NF-κB activation but also for the suppression of RIP1-dependent apoptosis and necroptosis. Through a series of functional assays, we identified a peptide (Tp-14) that blocks TRAF2 interaction with RIP1 and synergizes with AKT inhibition to induce apoptosis in BC cells that overexpress RIP1. Bioinformatic analyses revealed that TRAF2 and RIP1 are overexpressed in invasive BC, and significantly correlate with poor prognosis. Thus, we hypothesize that combined inhibition of AKT and TRAF2 phosphorylation or interaction with RIP1 synergistically induce apoptosis in BC cells that overexpress TRAF2 and RIP1. To test this hypothesis, we propose the following specific aims. Aim-1. Determine the mechanisms of signaling crosstalks between the PI3K-AKT and TBK1-TRAF2 pathways and identify biomarkers that predict BC cell response to combined AKT and TBK1 inhibition. Aim-2. Evaluate the therapeutic efficacy of combined AKT and TBK1 inhibition in BC xenograft models. Aim-3. Determine how blockade of TRAF2 interaction with RIP1 affects BC cell survival in vitro and xenograft tumor growth in vivo. Our proposals will shed new lights on the mechanisms underlying BC cell resistance to AKT inhibition and identify biomarkers for combined inhibition of AKT and TRAF2 phosphorylation or interaction with RIP1 for BC therapy.

乳腺癌（BC）是最常见的恶性肿瘤，也是癌症的第二大原因 西方妇女的死亡率。与大多数其他实体瘤一样，转移和耐药性是 死亡的主要原因。在约80％的卑诗省案件中，由于该pi3k-akt途径被异常激活 编码途径成分的基因的改变，例如RAS，HER2，PTEN，PIK3C和AKT。这 途径调节多个细胞过程，以促进BC的发展，生长，转移和药物 反抗。因此，目前在全球范围内正在进行100多次临床试验以评估治疗 BC中PI3K和AKT抑制剂的效率；但是，初始数据表明抑制此途径是 无效或经常会导致疾病的抵抗和缓解。那，识别 迫切需要其他靶标和治疗组合。我们以前绘制了traf2 磷酸化位点，并报道TRAF2 Ser-11磷酸化增强了NF-κB激活以促进 在细胞应激条件下的癌细胞存活。最近，我们发现BC中对AKT的抑制作用 细胞导致TBK1对TRAF2的磷酸化增加，并抑制Akt和TBK1 协同诱导BC细胞系的凋亡在体外，并显着抑制Xenographic BC肿瘤生长 体内。 TBK1及其亲密的同源物IKKε是丝氨酸/苏氨酸激酶，在BC的65-70％中过表达 在BC细胞存活中起关键作用，主要是通过在Ser-11处直接磷酸化TRAF2。在癌细胞中， TRAF2组成型招募潜在的E3连接酶CIAP1和CIAP2（CIAPS）以RIP1催化其非规范性 泛素化，这不仅对于NF-κB激活至关重要，而且对RIP1依赖性抑制也是必不可少的 凋亡和坏死性。通过一系列功能测定，我们确定了阻止的肽（TP-14） TRAF2与RIP1的相互作用并与Akt抑制协同作用，以诱导BC细胞中的凋亡 过表达RIP1。生物信息学分析表明，在侵入性BC中，TRAF2和RIP1过表达， 并与预后不良显着相关。这是我们假设对Akt和 TRAF2磷酸化或与RIP1的相互作用在BC细胞中诱导过表达的细胞中凋亡 TRAF2和RIP1。为了检验这一假设，我们提出了以下特定目标。 AIM-1。确定 PI3K-AKT和TBK1-TRAF2途径之间的信号传导串扰机制并识别生物标志物 这可以预测BC细胞对AKT和TBK1抑制的组合反应。 AIM-2。评估治疗效率 在BC特征模型中，合并的AKT和TBK1抑制作用。 AIM-3。确定traf2的封闭方式 与RIP1的相互作用会在体内影响BC细胞的存活和异种移植肿瘤的生长。我们的建议将脱落 BC细胞对AKT抑制的抗性机制的新灯 AKT和TRAF2磷酸化或与RIP1相互作用进行BC治疗的结合抑制作用。