Reprogramming the Tumor Microenvironment in Ovarian Cancer

项目摘要 高级别浆液性卵巢癌（HGSOC）是妇科恶性肿瘤死亡的主要原因。 大多数患者在手术后最初对化疗有反应，但约80%的患者会复发， 抵抗治疗。免疫疗法已显示出巨大的前景，但在HGSOC中的疗效有限。的 HGSOC肿瘤微环境（TME）是高度免疫抑制性的，这被假设为促进HGSOC肿瘤微环境（TME）。 肿瘤免疫逃避我们已经开发了两种新的可植入的同基因小鼠卵巢肿瘤模型， 将允许对驱动免疫逃避的肿瘤和宿主特异性信号进行分子分析。通过选择 对于小鼠的侵袭性生长，我们已经广泛地表征了KMF细胞（KRas，Myc， 和FAK），其表现出与HGSOC的许多表型相似性;内在的化学抗性和有效的免疫应答。 镇压我们将重点关注FAK（粘着斑激酶），一种酪氨酸激酶的典型支持细胞 运动信号FAK是HGSOC中第五高扩增的基因，并且超过65%的患者表现出 FAK mRNA升高，预后不良。使用药理学FAK抑制剂，FAK敲除， FAK的再表达，互补，以及荷瘤小鼠KMF细胞的生物信息学分析，我们发现， FAK驱动一组选定的细胞因子和肿瘤相关表面蛋白的表达， 调节肿瘤生长和免疫逃避。抑制FAK导致骨髓源性 抑制细胞（MDSC）募集，增加CD 4和CD 8 T细胞肿瘤浸润，并减少 PD-L1、CD 112和CD 155检查点调节蛋白在体内KMF细胞上的表达。这些变化 与卵巢TME通过FAK抑制的正常化或重编程一致， 方式FAK抑制还防止KMF模型中血性腹水形成。新开发的T 抗原驱动的FAK floxed小鼠卵巢癌模型（MOVCAR）显示，FAK缺失可防止肿瘤发生， 在同基因低T小鼠中生长。FAK-null MOVCAR肿瘤被CD 45+白细胞浸润，并且当 在免疫缺陷小鼠中评估，原位FAK无效MOVCAR肿瘤生长增强。这项建议 将检验肿瘤内源性FAK激活促进免疫抑制相关变化的假设， 的TME。Aim-1将使用一种新的诱导型FAK表达系统来评估FAK的核定位， 激酶依赖性信号驱动恶性肿瘤、趋化因子表达和MDSC募集。Aim-2将测试 CD 112/CD 155免疫检查点蛋白表达的作用和FAK抑制是否可能与联合收割机结合 针对TIGIT（具有IG和ITIM结构域的T细胞免疫受体）的抗体通过对T细胞的作用来限制肿瘤生长 细胞Aim-3将使用FAK的诱导型敲除，相关Pyk 2激酶的诱导型敲除（新模型），或诱导型敲除。 用KMF可植入肿瘤模型检测小鼠内皮细胞中激酶失活FAK的表达， TME上的基质FAK和Pyk 2信号传导。这些小鼠研究，以及对患者肿瘤的分析， 为FAK抑制在增强HGSOC免疫治疗功效方面的作用提供了重要见解。

PROJECT SUMMARY High-grade serous ovarian cancer (HGSOC) is the leading cause of death from gynecologic malignancies. Most patients initially respond to chemotherapy after surgery, yet ~80% will recur with disease that becomes resistant to treatment. Immune therapies have shown great promise, but with limited efficacy in HGSOC. The HGSOC tumor microenvironment (TME) is highly immuno-suppressive and this is hypothesized to promote tumor immune evasion. We have developed two new implantable syngeneic mouse ovarian tumor models that will allow for the molecular analysis of tumor- and host-specific signals driving immune evasion. By selecting for aggressive growth in mice, we have extensively characterized KMF cells (gains in genes for KRas, Myc, and FAK) that exhibit many phenotypic similarities to HGSOC; intrinsic chemo-resistance and potent immune suppression. We will focus on FAK (focal adhesion kinase), a tyrosine kinase canonically supporting cell motility signaling. FAK is the fifth highest amplified gene in HGSOC and greater than 65% of patients exhibit elevated FAK mRNA with poor prognostic significance. Using pharmacological FAK inhibitors, FAK knockout, FAK re-expression, complementation, and bioinformatic analyses of KMF cells in tumor-bearing mice, we find that FAK drives the expression of a select group of cytokines and tumor-associated surface proteins involved in regulating tumor growth and immune evasion. Inhibiting FAK results in decreased myeloid-derived suppressor cell (MDSC) recruitment, increased CD4 and CD8 T cell tumor infiltration, and decreased expression of PD-L1, CD112, and CD155 checkpoint regulatory proteins on KMF cells in vivo. These changes are consistent with a normalization or reprogramming of the ovarian TME by FAK inhibition in a tumor-intrinsic manner. FAK inhibition also prevents bloody ascites formation in the KMF model. A second newly-developed T antigen-driven FAK floxed mouse ovarian carcinoma model (MOVCAR) revealed that FAK loss prevents tumor growth in syngeneic low-T mice. FAK-null MOVCAR tumors were infiltrated by CD45+ leukocytes, and when evaluated in immune-deficient mice, orthotopic FAK-null MOVCAR tumor growth was enhanced. This proposal will test the hypothesis that tumor-intrinsic FAK activation facilitates immune-suppressive related changes to the TME. Aim-1 will use a new inducible FAK expression system to evaluate FAK nuclear localization- and kinase-dependent signals driving malignancy, chemokine expression, and MDSC recruitment. Aim-2 will test the role CD112/CD155 immune checkpoint protein expression and whether FAK inhibition may combine with antibodies to TIGIT (T cell immunoreceptor with Ig and ITIM domains) to limit tumor growth via effects on T cells. Aim-3 will use an inducible knockout of FAK, of the related Pyk2 kinase (new model), or inducible expression of kinase-inactive FAK in mouse endothelial cells, with the KMF implantable tumor model, to test stromal FAK and Pyk2 signaling on the TME. These mouse studies, with analyses of patient tumors, will provide important insights on the role of FAK inhibition to enhance immunotherapy efficacy for HGSOC.