Intravesical Immunotherapy of Spontaneous Canine Invasive Urothelial Carcinoma

项目摘要 浸润性膀胱癌是一种致命的疾病，通常需要改变生活的手术切除膀胱癌。 膀胱，以防止或限制转移。最近批准的五种检查点抑制剂用于晚期或难治性 膀胱癌证明了其对免疫疗法的响应性。然而，只有不到一半的先进 膀胱癌患者受益于检查点免疫疗法，并且抗肿瘤应答通常是短暂的。 我们先前在小鼠中的临床前研究表明，用白细胞介素- 12（IL-12）与粘膜粘附性生物聚合物壳聚糖（CS）配制，即，CS/IL-12，可以消除几乎所有 以T细胞依赖性方式建立原位膀胱肿瘤。这些研究还表明， 膀胱内CS/IL-12可以诱导强烈的远位反应，消除远处未治疗的膀胱 大多数小鼠的肿瘤。尽管这些数据是有希望的，但移植性小鼠膀胱肿瘤的一些局限性 模型阻碍了临床转化。因此，本申请提出评估以下化合物的安全性和活性： 膀胱内CS/犬IL-12（cIL-12）免疫治疗宠物犬自发性尿路上皮浸润 膀胱癌（UC）。犬和人类膀胱癌之间有许多相似之处 包括肿瘤发生的机制、转移的速率和部位以及可区分的分子亚型。 鉴于这些相似之处，在狗身上成功的治疗更有可能在人身上成功。 本项目的目的是：1）证明膀胱内CS/cIL-12免疫治疗可以 安全地诱导抗犬侵袭性UC的抗肿瘤免疫;和2）确定犬膀胱癌是否是一种 这是一个有用的模型，用于评估这种和其他新的免疫疗法。第一个目标将帮助准备 膀胱内CS/IL-12转化为人类临床试验，而第二个目标将有助于膀胱 癌症研究人员克服了啮齿动物模型的局限性， 人类膀胱癌为了实现这些目标，制定了两个具体目标。 目的1关注安全性，因为CS/cIL-12从未在犬中进行过评价。在合成和 为了在体外验证重组cIL-12，我们将进行膀胱内CS/cIL-12的剂量递增研究， 患有自发性膀胱浸润性UC的宠物犬。目标1将建立一个推荐剂量（RD）的基础上 使用临床检查和实验室测试相结合的安全读数。提出 药代动力学和免疫表型研究将调查可能的全身吸收， 膀胱内免疫疗法的传播和由此产生的免疫影响。目标2将评估抗肿瘤 在一个扩大的患有膀胱炎的狗队列中， 癌相关研究将确定膀胱内CS/cIL-12是否影响T细胞浸润，肿瘤- 免疫微环境、新抗原反应性和/或T细胞克隆性。分子亚型的影响 并且将评估肿瘤突变对抗肿瘤和/或免疫应答的负荷。

PROJECT SUMMARY Invasive bladder cancer is a lethal disease that often requires life-altering surgical removal of the bladder to prevent or limit metastasis. Recent approvals of five checkpoint inhibitors for advanced or refractory bladder cancers demonstrate its responsiveness to immunotherapy. However, less than half of advanced bladder cancer patients benefit from checkpoint immunotherapy and antitumor responses are often transient. Our previous preclinical studies in mice demonstrated that intravesical immunotherapy with interleukin- 12 (IL-12) formulated with the mucoadhesive biopolymer chitosan (CS), i.e., CS/IL-12, can eliminate nearly all established orthotopic bladder tumors in a T cell-dependent manner. These studies also demonstrated that intravesical CS/IL-12 can induce robust abscopal responses with the elimination of distant, untreated bladder tumors in most mice. Although these data are promising, several limitations of implanted murine bladder tumor models have hindered clinical translation. Thus, this application proposes to evaluate the safety and activity of intravesical CS/canine IL-12 (caIL-12) immunotherapy in pet dogs with spontaneous invasive urothelial carcinoma (UC) of the bladder. There are numerous similarities between canine and human bladder cancers including mechanisms of tumorigenesis, rates and sites of metastasis, and distinguishable molecular subtypes. Given these similarities, treatments found to be successful in dogs are more likely to be successful in people. The objectives of this project are: 1) to demonstrate that intravesical CS/caIL-12 immunotherapy can safely induce antitumor immunity against canine invasive UC; and 2) to determine if canine bladder cancer is a useful model for the evaluation of this and other novel immunotherapies. The first objective will help prepare intravesical CS/IL-12 for translation into human clinical trials, while the second objective will help bladder cancer researchers overcome the limitations of rodent models and provide a more faithful representation of human bladder cancer. To accomplish these objectives, 2 specific aims have been designed. Aim 1 is focused on safety, as CS/caIL-12 has never been evaluated in dogs. After synthesizing and validating recombinant caIL-12 in vitro, we will perform a dose-escalation study of intravesical CS/caIL-12 in pet dogs with spontaneous invasive UC of the bladder. Aim 1 will establish a recommended dose (RD) based on safety readouts that utilize a combination of clinical examinations and laboratory tests. Proposed pharmacokinetic and immunophenotyping studies will investigate the possible systemic uptake and dissemination of intravesical immunotherapy and the resulting immune impacts. Aim 2 will assess antitumor and immunological responses to the RD of intravesical CS/caIL-12 in an expanded cohort of dogs with bladder cancer. Correlative studies will determine if intravesical CS/caIL-12 influences T cell infiltration, the tumor- immune microenvironment, neoantigen reactivity and/or T cell clonality. The influence of molecular subtype and tumor mutational burden on antitumor and/or immune responsiveness will be assessed.