Targeting the DNA Damage Response in HPV+ Head and Neck Cancer

项目摘要 人乳头状瘤病毒（HPV）阳性的头颈部鳞状细胞癌（HNSCC）是一个越来越多的公众 健康负担，并已超过宫颈癌，成为最常见的HPV相关恶性肿瘤， 美国的虽然HPV+ HNSCC患者通常具有良好的生存率，但他们患有终身感染， 放化疗相关的疾病当前数据不足以告知标准品的去强化 放化疗或靶向治疗的发展。我的最终目标是了解 HPV在HNSCC发展过程中破坏DNA损伤反应（DDR）信号传导的机制， 从而为新靶向治疗的合理设计提供信息。在考虑新战略时， 对照HPV+ HNSCC，我注意到HPV的致癌E6和E7蛋白废除了肿瘤抑制途径， 并损害DDR信号传导以引起基因组不稳定性。门德斯实验室和其他人已经建立了DDR 通过特异性抑制剂AZD 1775（WEE 1 i）抑制激酶WEE 1作为HNSCC的新治疗策略， 并且HPV+ HNSCC肿瘤是高度敏感的。WEE 1抑制导致S期复制应激（RS） 以及无法修复的DNA损伤联合遗传毒性化疗（例如，顺铂），WEE 1 i废除了 G2/M检查点，导致过早有丝分裂。我最近发现HPV 16 E6/E7癌蛋白使 通过激活FOXM 1-CDK 1电路驱动有丝分裂基因，HNSCC细胞与WEE 1 i单药治疗 表达和DNA损伤。我还发现基础FOXM 1活性升高易导致HPV+ HNSCC， WEE 1 i诱导的毒性。接下来，我使用RNAi基因筛选来识别RS和DDR靶点， 根据我迄今为止的发现，我假设E6/E7对RS和DDR通路的破坏 为包括WEE 1 i在内的联合靶向治疗提供可利用的漏洞。我打算澄清一下 HPV使癌细胞对WEE 1 i诱导的复制失败敏感的机制（Aim 1）， 在WEE 1抑制后损害DNA修复途径（Aim 2）。我会用老鼠的癌症模型来测试 用于靶向HPV+ HNSCC中的RS/DDR缺陷的新的治疗组合， 它们是最有效的。同时，我将使用靶向定量蛋白质组学方法来确定 E6/E7特异性RS和DDR对WEE 1 i的反应，以及多板流式细胞术，以确定WEE 1 i。 在免疫活性小鼠中E6/E7驱动的肿瘤的免疫景观的相关变化。这个奖项 将帮助我发展我的科学思想，并提高我在使用小鼠模型方面的能力， 忠实地概括了人类癌症。我在训练期间所取得的科学进步 这对我建立一个独立的研究项目的最终目标至关重要，该项目的重点是HPV如何驱动 HNSCC的发展以及如何更安全有效地治疗HPV+ HNSCC。

Project Summary Human papilloma virus (HPV)-positive head and neck squamous cell carcinoma (HNSCC) is a growing public health burden and has already surpassed cervical cancer as the most common HPV-related malignancy in the United States. While HPV+ HNSCC patients have generally good survival, they suffer from life-long chemoradiotherapy-related morbidities. Current data is insufficient to inform de-intensification of standard chemoradiotherapy or the development of targeted therapies. My ultimate goal is to understand the mechanisms by which HPV disrupts DNA damage response (DDR) signaling during HNSCC development, and to thereby inform the rational design of new targeted therapies. In considering new strategies to effectively control HPV+ HNSCC, I noted that HPV’s oncogenic E6 and E7 proteins abrogate tumor suppressor pathways and impair DDR signaling to cause genomic instability. The Mendez lab and others have established DDR kinase WEE1 inhibition via the specific inhibitor AZD1775 (WEE1i) as a new therapeutic strategy in HNSCC, and that HPV+ HNSCC tumors are hypersensitive. WEE1 inhibition causes S-phase replication stress (RS) and irreparable DNA damage. Combined with genotoxic chemotherapy (e.g., cisplatin), WEE1i abrogates the G2/M checkpoint and causes premature mitosis. I recently showed that HPV16 E6/E7 oncoproteins sensitize HNSCC cells to WEE1i monotherapy through activation of a FOXM1-CDK1 circuit that drives mitotic gene expression and DNA damage. I also showed that elevated basal FOXM1 activity predisposes HPV+ HNSCC to WEE1i-induced toxicity. Next, I used an RNAi genetic screen to identify RS and DDR targets that synergize with WEE1i; based on my findings to date, I hypothesize that disruption of RS and DDR pathways by E6/E7 provide exploitable vulnerabilities for a combination targeted therapy that also includes WEE1i. I plan to clarify the mechanisms by which HPV sensitizes cancer cells to WEE1i-induced replication failure (Aim 1) and compromises DNA repair pathways upon WEE1 inhibition (Aim 2). I will use murine cancer models to test novel therapeutic combinations for targeting RS/DDR defects in HPV+ HNSCC and identify the situations in which they are most effective. In parallel, I will use a targeted quantitative proteomics approach to determine the E6/E7-specific RS and DDR responses to WEE1i, and multi-panel flow cytometry to determine the WEE1i- associated changes in the immune landscape of E6/E7-driven tumors in immunocompetent mice. This award will help me develop my scientific ideas and increase my competency in working with the mouse models that faithfully recapitulate human cancer. The scientific advances that I make during this training period will be critical to my ultimate goal of establishing an independent research program that focuses on how HPV drives HNSCC development and how HPV+ HNSCC might be more safely and effectively treated.