Hijacking cancer driver to activate cell death by chemically induced proximity

摘要 个性化的靶向癌症治疗，虽然最初有效，但会导致耐药性和疾病进展 &gt；50%的患者在开始治疗后几个月内迅速恢复。这些疗法直接抑制了 催化和/或配体诱导的癌症驱动功能，通过突变逃逸或 表观遗传/转录旁路。为了解决突变逃逸问题，最近的治疗方法利用 化学诱导邻近(CIP)：将两种蛋白质募集到邻近的双功能分子。 紧急治疗效果。然而，目前基于CIP的治疗仅限于降解，这会导致 从类似的抗药性反馈机制直接抑制癌症的驱动因素。然后，我们认识到 所有癌症基因中有45%是直接转录调控基因。因此，本提案勾勒出一种新颖的CIP-- 使治疗范式能够劫持癌症驱动因素，以放大治疗性转录程序 直接杀死癌细胞。 具体地说，这项提议的目标是劫持乳腺癌中的雌激素受体，以驱动过度表达 诱导癌细胞死亡的促凋亡因子。首先，我将系统地定义最有力的亲- 转录上调诱导多种雌激素受体阳性细胞死亡的凋亡因子 乳腺癌细胞株。其次，我将鉴定并验证调节这些前-核糖核酸的转录因子。 将生物信息学分析与高通量反式激活剂诱导相结合的凋亡因子 招聘屏幕。最后，我将证明乳腺癌中的雌激素受体可以被劫持 通过将其招募到内源性标记的转录因子调节器来靶向转录上调 有效的促凋亡因子和靶向dCas9。我将一起确认和证明雌激素 受体可被CIP诱导募集到一种转录因子调节的促凋亡因子来诱导 乳腺癌细胞死亡。 上述目标的成功完成不仅将建立一种新的治疗方法 雌激素受体阳性乳腺癌，但也是一种可推广的跨多种癌症的治疗范例 有反式激活癌症驱动因素的类型。此外，我将为以后的工作确定强有力的候选人 治疗性异双功能分子研究进展。提交的建议还反映了我的培训目标 成为连接化学生物学工具和表观遗传学基因的跨学科医生-科学家 为解决癌症生物学和治疗中的关键问题和需求而制定的法规。

Abstract Personalized targeted cancer therapy, while initially effective, leads to resistance and disease progression in >50% of patients in as rapidly as few months after initiating therapy. These therapies directly inhibit the catalytic and/or ligand-induced functions of the cancer driver, leading to resistance via mutational escape or epigenetic/transcriptional bypass. To address mutational escape, recent therapeutic approaches leverage Chemically induced Proximity (CiP): bifunctional molecules that recruit two proteins into proximity for an emergent therapeutic effect. However, current CiP-based therapies are limited to degradation, which suffers from similar feedback mechanisms of resistance as direct inhibition of the cancer driver. Then, we recognized that 45% of all cancer genes are direct transcriptional regulators. Therefore, this proposal outlines a novel CiP- enabled therapeutic paradigm to hijack cancer drivers to amplify a therapeutic transcriptional program to directly kill cancer cells. Specifically, the goal of this proposal is to hijack the estrogen receptor in breast cancer to drive overexpression of pro-apoptotic factors to induce cancer cell death. First, I will systematically define the most potent pro- apoptotic factors for transcriptional upregulation induced cell death across multiple estrogen receptor positive breast cancer cell lines. Second, I will identify and validate transcription factors that regulate these pro- apoptotic factors by integrating bioinformatic analysis with a high throughput transactivator inducible recruitment screen. Finally, I will demonstrate that estrogen receptor in breast cancer can be hijacked for targeted transcriptional upregulation by recruiting it to an endogenously tagged transcription factor regulator of potent pro-apoptotic factors and to a targeted dCas9. Together, I will identify and demonstrate that estrogen receptor can be inducibly recruited by CiP to a transcription factor regulator of pro-apoptotic factors to induce breast cancer cell death. The successful completion of the aims described will establish not only a novel therapeutic approach for estrogen receptor positive breast cancer but also a generalizable therapeutic paradigm across multiple cancer types with transactivating cancer drivers. Furthermore, I will identify robust candidates for subsequent therapeutic heterobifunctional molecule development. The proposal presented also reflects my training goals of becoming an interdisciplinary physician-scientist bridging chemical biology tools and epigenetic gene regulation to address critical problems and needs in cancer biology and therapy.