Program the Immune System against RAS-driven Cancer

摘要 尽管近几十年来取得了很大的进步，但许多类型的癌症仍然几乎是致命的。胰腺 导管腺癌(PDAC)就是一个显著的例子。其中一个挑战是，绝大多数(95%) 的PDAC是由一种名为KRAS的基因突变驱动的，这些KRAS突变是出了名的困难 以常规药物为靶点。第一代抗癌药物是基于小分子的，第二代是基于小分子的 新一代生物制品(大的生物分子，如与癌细胞特异结合的抗体)，以及最新的 产生细胞(设计用于识别和消融癌细胞)。在这里，我们的长期目标是展示 新一代治疗学，使用“回路”作为药物。电路比喻指的是 生物分子被设计成相互调节，并在活细胞内处理信息。虽然很传统 分析输出指标以通知医生，医生然后做出治疗决定，我们的电路关闭环路， 并将作为分析和治疗的工具。它是一种分子和细胞分析技术 它可以查询活细胞，并在没有人工干预的情况下实时启动治疗输出。 具体地说，我们将创建电路来对免疫系统进行编程，并模拟“非望远镜效应”，即 偶尔观察到，局部肿瘤治疗后远处肿瘤缩小，很可能是由于免疫 系统学习被治疗的肿瘤的“特征”，然后进行推断。我们将首先创建该建筑 用于这种电路的模块：可以询问细胞是否处于癌症状态的传感器，可以 控制细胞发出的信号以参与免疫系统，以及连接传感器和 致动器。这些努力将受益于我们专门使用蛋白质构建电路的经验，这是 具有技术优势，例如易于交付和在不同蜂窝网络中的功能健壮 与更传统的基于蛋白质-DNA相互作用构建电路的方法相比，这是一种新的方法。我们会 然后将这些积木组装成电路，并量化和优化它们在培养细胞中的操作。 利用我们在PDAC小鼠模型方面的专业知识，我们最终将在体内测试这些电路的有效性。这个 前提是对癌细胞产生的特定产物进行编程，以动员免疫系统，然后溶解 这些细胞允许免疫系统访问癌症中唯一存在的所有蛋白质序列。 这些死亡的癌细胞将基本上作为疫苗来对抗其他表现出类似蛋白质的细胞。 序列特征。我们将通过模仿已知的一种特定类型的细胞死亡来实现这种疫苗效果 动员免疫系统，或对癌细胞进行编程，以直接和人工激活T细胞-免疫 负责识别和消融癌细胞的细胞。 这项提议的预期结果不仅是临床前证据支持一种新的、强大的 治疗KRAS驱动的PDAC，也是合成生物分子生物医学前景的原则证明 治疗其他顽固性癌症及其他类型癌症的电路。

Abstract Despite the great progress in recent decades, many types of cancer remain almost fatal. Pancreatic ductal adenocarcinoma (PDAC) is a remarkable example. One of the challenges is that the vast majority (95%) of PDACs are driven by mutations within a gene called KRAS, and these KRAS mutations are notoriously difficult to target with conventional drugs. The first generation of cancer drugs are based on small molecules, the second generation biologics (large biomolecules such as antibodies that specifically bind to cancer cells), and the latest generation cells (engineered to recognize and ablate cancer cells). Here our long-term goal is to demonstrate a new generation of therapeutics, using “circuits” as medicine. Circuits metaphorically refer to collections of biomolecules engineered to regulate each other and process information inside living cells. While conventional analyses output metrics to inform physicians, who then make therapeutic decisions, our circuits close the loop, and will serve as both the analytic and the therapeutic tools. It is a molecular and cellular analysis technology that queries living cells and actuates therapeutic outputs in real time without human intervention. Specifically, we will create circuits to program the immune system and emulate the “abscopal effect”, the occasional observation that distant tumors shrink when local tumors are treated, most likely due to the immune system learning the “signature” of the treated tumors and then extrapolating. We will first create the building blocks for such circuits: sensors that can interrogate whether a cell is in a cancerous state, actuators that can control the signals sent by cells to engage the immune system, and processors that connect the sensors and the actuators. These efforts will benefit from our experience of building circuits exclusively using proteins, which features technical advantages, such as ease of delivery and robustness of functionality in different cellular contexts, compared to more conventional ways of building circuits based on protein-DNA interactions. We will then assemble these building blocks into circuits, and quantify and optimize their operation in cultured cells. Leveraging our expertise in mouse models of PDACs, we will finally test these circuits’ efficacy in vivo. The premise is to program the outputs specifically from cancer cells to mobilize the immune system and then lyse these cells to grant the immune system access to all protein sequences that are uniquely present in cancer. These dead cancer cells will serve essentially as vaccines against other cells that exhibit similar protein sequence profiles. We will achieve this vaccination effect by either mimicking a specific type of cell death known to mobilize the immune system, or program the cancer cells to directly and artificially activate T cells – immune cells responsible for recognizing and ablating cancer cells. The expected outcomes of this proposal are not only preclinical evidence supporting a novel, powerful therapy for KRAS-driven PDAC, but also a proof of principle for the biomedical promise of synthetic biomolecular circuits for other recalcitrant types of cancer and beyond.