Validation of WEE1 kinase as a clinical target in KRAS-mutant pancreatic cancer

胰腺导管腺癌(PDAC)是美国癌症相关死亡的第三大原因。 各州。PDAC是最致命的癌症，5年存活率高达8%。超过95%的PDAC拥有 突变激活的KRAS癌基因，是PDAC生长的有效驱动因素。尽管近乎普遍的 PDAC对致癌KRAS的依赖性及临床有效的抗KRAS治疗进展 仍然难以捉摸。一种有希望的方法涉及抑制KRAS效应器信号，特别是抑制 RAF-MEK-ERK丝裂原活化蛋白激酶(MAPK)级联。然而，我假设额外的 激酶还必须有助于KRAS驱动的PDAC增长。为了解决这种可能性，我们应用了不偏不倚的 Kinome全化学蛋白质组学策略(MIB-MS)以识别新的KRAS调节的激酶。在紧急情况下 通过对KRAS的抑制，我们发现了上调和下调的蛋白激酶。将此数据集与我的 鉴定DNA损伤的ERK依赖转录组的RNA-Seq数据集的分析 反应(DDR)和细胞周期调节基因特征，我选择了WEE1 DNA损伤检查点激酶 以作进一步评估。我的初步结果确定，突变的KRAS可能通过 基因转录和蛋白质稳定性都提高了。我还发现WEE1的药物抑制作用 抑制PDAC的体外生长，但在WEE1抑制时观察到ERK的激活。投机 这种ERK的激活是一种可以驱动耐药性的补偿机制，我发现同时 ERK和WEE1抑制在体外协同抑制PDAC生长。这些结果为下一步研究提供了基础 对于我的研究和我两个目标的理论基础：(1)描述KRAS监管的机制 Wee1表达/丰度，并确定WEE1缺失如何促进依赖KRAS的PDAC生长； 以及，(2)应用先进的PDAC(器官和同种原位肿瘤)临床前模型来评估 临床候选WEE1抑制剂Adavosertib单独或联合应用的疗效 临床候选ERK抑制剂ulxertitib。我研究的科学创新涉及利用DNA 检查点抑制剂是KRAS突变胰腺癌的治疗脆弱性，目前的标准是 常规的细胞毒药物治疗仍然无效。我的研究将进一步阐明其基本机制。 KRAS信号转导，并另外确定用于临床评估的新疗法。这项研究将为我提供 培训癌细胞和分子生物学，临床前药物评估，并实施 生物信息学分析的计算工具。我还将参加指导临床活动，重点是 对不同的肿瘤科患者的护理。总体而言， 北卡罗来纳大学教堂山分校，我在Lineberger内部经验丰富的合作者网络 全面的癌症中心，钱宁·德尔博士的出色指导将推动和准备我 成为癌症生物学领域的顶尖内科科学家。

Pancreatic ductal adenocarcinoma (PDAC) is the 3rd leading cause of cancer-related mortality in the United States. PDAC is the deadliest cancer, with an abysmal 5-year survival rate of 8%. Over 95% of PDAC harbor a mutationally activated KRAS oncogene, a well-validated driver of PDAC growth. Despite the near-universal dependence of PDAC on oncogenic KRAS, the development of clinically effective anti-KRAS therapies for PDAC remains elusive. One promising approach involves inhibition of KRAS effector signaling, particularly inhibitors of the RAF-MEK-ERK mitogen-activated protein kinase (MAPK) cascade. However, I hypothesize that additional kinases must also contribute to KRAS-driven PDAC growth. To address this possibility, we applied an unbiased kinome-wide chemical proteomics strategy (MIB-MS) to identify novel KRAS-regulated kinases. Upon acute KRAS suppression, we identified both upregulated and downregulated kinases. Partnering this dataset with my analyses of an RNA-Seq dataset profiling the ERK-dependent transcriptome that identified DNA-damage response (DDR) and cell-cycle regulation gene signatures, I selected the WEE1 DNA damage checkpoint kinase for further evaluation. My preliminary results determined that mutant KRAS may regulate WEE1 activity through both gene transcription and increased protein stability. I also found that pharmacologic inhibition of WEE1 suppressed PDAC growth in vitro, but additionally observed ERK activation upon WEE1 inhibition. Speculating that this ERK activation is a compensatory mechanism that can drive drug resistance, I found that concurrent ERK and WEE1 inhibition synergistically suppressed PDAC growth in vitro. These results provide the foundation for my studies and the rationale for my two aims: (1) to delineate the mechanisms by which KRAS regulates WEE1 expression/abundance and determine how WEE1 loss contributes to KRAS-dependent PDAC growth; and, (2) to apply advanced preclinical models of PDAC (organoids and syngeneic orthotopic tumors) to assess the therapeutic impact of the clinical candidate WEE1 inhibitor adavosertib, alone or in combination with the clinical candidate ERK inhibitor ulixertinitib. The scientific innovation of my studies involves exploiting DNA checkpoint inhibitors as a therapeutic vulnerability of KRAS-mutant pancreatic cancer, where current standard of care remains ineffective conventional cytotoxic drugs. My studies will further elucidate basic mechanisms of KRAS signaling and additionally identify new therapies for clinical evaluation. This research will provide me with training in cancer cell and molecular biology, preclinical drug assessment, and the implementation of computational tools for bioinformatics analyses. I will also participate in mentored clinical activities focused on the care of a diverse set of oncology patients. Overall, the superior research and clinical opportunities at the University of North Carolina at Chapel Hill, my network of experienced collaborators within the Lineberger Comprehensive Cancer Center, and the exceptional mentoring of Dr. Channing Der will propel and prepare me to become a leading physician-scientist in cancer biology.