Mechanisms Determining Dysregulation of the NRF2 Oxidative Stress Response in Head and Neck Squamous Cell Carcinoma

摘要 首席调查员特拉维斯·施兰克博士，医学博士，博士，是该大学一年级的教员 北卡罗来纳州耳鼻喉科。他被聘为外科医生兼科学家，目前 有75%的受保护时间用于研究。他过去在计算生物物理学和实验方面的培训 生物化学激发了他追求计算领域独立研究事业的动力，并使他具备了这方面的能力 基因组学和头颈癌分子生物学。所提出的研究目标是 PI正在努力改进基于RNA的方法来识别NRF2活性的头颈部鳞状细胞 癌(HNSCC)肿瘤。 Nrf2是细胞氧化应激反应的关键转录调节因子，并与 对多种癌症类型的不良患者结局和辐射反应。NRF2的突变激活是 在8%的HPV阴性(HPV-)HNSCC中观察到。然而，我们基于RNA转录的估计表明 NRF2在24%的HPV-HNSCC中异常激活。这项工作发现了非典型的NRF2和CUL3 与NRF2激活相关的变体。这些变体的功能后果将是 已调查(目标1)。我们还发现前激素神经降压素在NRF2活动期HNSCC中高表达 无NRF2通路突变的肿瘤。我们的初步数据表明，神经降压素前体可能激活NRF2， 通过以前未报道的与Keap1(NRF2稳定性的调节因子)的相互作用。这一新的功能 神经降压素原将在AIM 2中进行研究。众所周知，抑制NRF2活性会使放射增敏 癌细胞。我们还发现了与HPV相关的NRF2靶标表达的部分抑制模式 (HPV+)HNSCC肿瘤，对辐射高度敏感。P14ARF在HPV+中也有高表达 HNSCC，结合NRF2，并抑制一些NRF2靶标的反式激活。目标3将探索这一假设 由于高水平的p14ARF，NRF2靶标被抑制，这有助于这些肿瘤的放射敏感性。 这项拟议的工作将产生影响的原因有几个：1)发展了肿瘤亚分类方法 解决肿瘤RNA表达数据的临床/基因组注释不完善的常见问题，2) 将探索神经降压素的前激素形式的第一个已知/报道的信号作用，以及3) 识别与辐射反应相关的NRF2靶点可能会提出新的治疗方法。 北卡罗来纳大学在癌症基因组学方面拥有非常强大的机构专业知识和资源。这个 指导委员会还在NRF2生物学、计算基因组学、p14ARF等关键项目方面拥有特定的专业知识 和神经降压素。总的来说，导师团队之前已经培训了四名K奖获得者，其中包括 两名外科医生-科学家，他们可以提供关键的职业指导。

ABSTRACT The principle investigator, Dr. Travis Schrank, MD, PhD, is a first-year faculty member in the University of North Carolina Department of Otolaryngology. He has been hired in a surgeon-scientist role and presently has 75% protected time for research. His past training in computational biophysics and experimental biochemistry have motivated and equipped him pursue an independent research career in computational genomics and head and neck cancer molecular biology. The presented research aims are an outgrowth of the PI's ongoing efforts to improve RNA based methods for identifying NRF2 active head and neck squamous cell carcinoma (HNSCC) tumors. NRF2 is the key transcriptional regulator of the cellular oxidative stress response, and has been related to poor patient outcome and radiation response in multiple cancer types. Mutational activation of NRF2 is observed in 8% of HPV negative (HPV-) HNSCC. However, our estimates based on RNA transcription suggest that NRF2 is aberrantly activated in 24% of HPV- HNSCC. This work has identified atypical NRF2 and CUL3 variants which are associated with NRF2 activation. The functional consequences of these variants will be investigated (Aim 1). We also find that the prohormone Neurotensin is highly expressed in NRF2 active HNSCC tumors without NRF2 pathway mutations. Our preliminary data suggest that pro-Neurotensin may activate NRF2, through a previously unreported interaction with KEAP1 (a regulator of NRF2 stability). This novel function of pro-Neurotensin will be investigated in Aim 2. Suppression of NRF2 activity is well known to radio-sensitize cancer cells. We have also identified a partially suppressed pattern of NRF2 target expression in HPV associated (HPV+) HNSCC tumors, which are highly sensitive to radiation. p14ARF is also highly expressed in HPV+ HNSCC, binds NRF2, and suppresses transactivation of some NRF2 targets. Aim 3 will explore the hypothesis that NRF2 target suppression due to high levels of p14ARF, contributes to the radio-sensitivity of these tumors. The proposed work will be impactful for several reasons, 1) the tumor subclassification method developed address the very common problem of imperfect clinical/genomic annotations of tumor RNA expression data, 2) the first known/reported signaling role for the prohormone form of Neurotensin will be explored, and 3) identification of NRF2 targets associated with radiation response may suggest novel approaches to treatment. UNC has exceptionally strong institutional expertise and resources related to cancer genomics. The mentorship committee also has key project specific expertise in NRF2 biology, computational genomics, p14ARF and Neurotensin. Collectively the mentorship team has previously trained four K award recipients and includes two surgeon-scientists who can provide critical career guidance.