MRI-Guided Cryoablation and Imaging-Guided Intratumoral Delivery of STING Agonist Immunotherapy to Target Localized and Metastatic Canine Osteosarcoma

骨肉瘤（OSA）发生在儿童/年轻人和狗中，年发病率为450 和25，000例病例，使狗成为一种有用的比较肿瘤学模型，用于开发 OSA治疗。不幸的是，在过去的三年里，OSA患者的预后已经趋于稳定。 几十年因此，除了标准治疗（SOC）手术和 化疗是非常必要的。作为治疗阻塞性睡眠呼吸暂停的一种新疗法，我们小组正在开发磁疗法， 共振成像（MRI）引导的冷冻治疗联合图像引导的瘤内注射 一种免疫佐剂。为此，我们将进行一项犬临床试验， 冷冻疗法单独或联合瘤内免疫佐剂给药， 发生的非转移性犬非典型性OSA。拟议的免疫相关研究将 为OSA肿瘤的免疫调节机制和免疫学机制提供了重要的见解。 治疗的影响，以指导未来的改进。虽然冷冻疗法直接杀死OSA肿瘤细胞， 我们的目的是激活患者的适应性免疫系统， 从垂死的肿瘤细胞中分离，并加入免疫佐剂的瘤内递送。以下 局部控制手术，我们假设启动的适应性免疫反应可以延迟或阻止 转移性疾病的发生，这是一致致命的。利用核磁共振成像，人们可以精确地确定 在没有暴露于电离辐射的情况下，通过冷冻疗法冷冻和杀死肿瘤组织的程度。 其他人已经证明了冷冻消融术后巨噬细胞和骨髓细胞的流入。经由 肿瘤内注射，我们将提供一种新的干扰素基因刺激因子（STING）激动剂， 冷冻疗法以激活浸润的先天免疫细胞。STING途径激活导致 广泛的细胞因子诱导，抗原呈递细胞的活化，以及随后的T细胞的引发， 细胞我们的具体目标是：1.为了确定OSA的MRI引导下冷冻消融术是否会产生 基于细胞因子测定、免疫组织化学（IHC）和免疫测定的免疫应答， 通过非侵入性成像评估，防止转移进展，从而增加总体 与SOC治疗相比的生存率。2.为了表征CT引导的免疫应答和安全性， STING激动剂在犬OSA中的肿瘤内施用。3.为了确定MRI引导的 冷冻消融联合CT引导的肿瘤内STING激动剂给药可预防转移性 与SOC治疗OSA相比，疾病进展和生存率。高发 OSA在具有高转移性疾病率的狗中的表达为研究提供了理想的动物模型 这种新的图像引导治疗OSA使用临床相关的成像系统， 用于快速翻译和应用于其他实体肿瘤。

Osteosarcoma (OSA) occurs in both children/young adults and in dogs, with an annual incidence of 450 and 25,000 cases, respectively, making dogs a useful comparative oncology model for the development of OSA treatments. Unfortunately, outcomes for patients with OSA have plateaued over the past three decades. Thus, new treatment approaches beyond the standard of care (SOC) surgery and chemotherapy are sorely needed. As a novel therapy for OSA, our group is developing Magnetic Resonance Imaging (MRI)-guided cryotherapy in conjunction with image-guided intratumoral injection of an immune adjuvant. To this end, we will perform a canine clinical trial comparing MRI-guided cryotherapy alone or in conjunction with intratumoral immune adjuvant administration in spontaneously occurring, non-metastatic, canine appendicular OSA. The proposed immune correlative studies will provide crucial insights into the mechanisms of immune regulation in OSA tumors and the immunologic impact of the therapies to guide future improvements. While cryotherapy directly kills OSA tumor cells, our intent is to activate the patient’s adaptive immune system against tumor antigens that are presented from the dying tumor cells, with the addition of intratumoral delivery of an immune adjuvant. Following local control surgery, we hypothesize that the primed adaptive immune response can delay or prevent the occurrence of metastatic disease, which is uniformly fatal. Using MRI, one can precisely determine the extent of tumor tissue that is frozen and killed by cryotherapy without exposure to ionizing radiation. Others have demonstrated an influx of macrophage and myeloid cells following cryoablation. Via intratumoral injection, we will deliver a novel Stimulator of Interferon Gene (STING) agonist following cryotherapy to activate the infiltrating innate immune cells. STING pathway activation results in extensive cytokine induction, the activation of antigen presenting cells, and subsequent priming of T cells. Our specific aims are: 1. To determine whether MRI-guided cryoablation of OSA generates an immune response based on cytokine assays, immunohistochemistry (IHC), and immunoassays that can prevent metastatic progression, as assessed by non-invasive imaging and thereby increase overall survival compared to SOC treatment. 2. To characterize the immune response and safety of CT-guided STING agonist intratumoral administration in canine OSA. 3. To determine whether MRI-guided cryoablation combined with CT-guided intratumoral STING agonist administration prevents metastatic disease progression and prolongs survival compared with SOC treatment for OSA. The high incidence of OSA in dogs with a high rate of metastatic disease provides an ideal animal model with which to study this novel image-guided treatment of OSA using clinically relevant imaging systems with the potential for rapid translation and application in other solid tumors.