Treating recurrent HNSCC with radiation and dual TGF-Beta/PD-L1.

项目2摘要 放射治疗（RT）通常用于局部复发的头颈部鳞状细胞癌 （HNSCC），但没有标准的伴随全身治疗存在，RT耐药率高。抗体 针对程序性死亡-1（PD-1）的抗肿瘤药物被FDA批准用于治疗复发/再发HNSCC，但 答复率低。RT通过引起DNA损伤和肿瘤细胞杀伤来诱导抗肿瘤免疫， 新抗原，以触发“原位肿瘤疫苗”和激活STING（IFN基因的刺激物）， 全身免疫激活。相反，RT也诱导转化生长因子-β1（TGFβ1）， 抑制子和PD-L1，PD-1的配体。这些RT效应使双重TGFβ/PD-L1抑制成为一种合理的方法。 在这个项目中进行测试。我们已经报道，TGFβ1在>60%的烟草相关性肺癌中升高， HNSCCs。TGFβ1介导的DNA修复有助于RT抗性。TGFβ1也有助于RT诱导的 毒性，例如，口腔粘膜炎和纤维化。使用我们的小鼠HNSCC模型，我们发现TGFβ/PD-L1双重 在具有高TGFβ1水平和高数量的肿瘤中，抑制剂根除SCC的效果优于单独使用抗PD-L1。 PD-L1+/CD 11b+细胞。我们还发现，TGFβ抑制减少了无胸腺小鼠的转移， CD 11b+骨髓细胞减少。我们假设在晚期HNSCC中，TGFβ/PD-L1双重抑制 增强RT诱导的原位疫苗接种，逆转免疫抑制，克服RT抗性 通过T细胞依赖性和非依赖性机制。我们将用实验来验证这一假设。 HNSCC患者样本的治疗、机制研究和分析。目的1将确定TGFβ/PD-1是否 L1双重抑制增强口腔鳞癌小鼠RT诱导的原位免疫和全身免疫激活 模型将使用小鼠SCC进行RT加TGFβ/PD-L1双重抑制的实验性治疗 细胞系原位移植到同基因小鼠，T细胞依赖性抗肿瘤机制将被证实。 在细胞和分子水平上进行分析。目标2将确定RT方案如何与 TGFβ/PD-L1抑制靶向小鼠和人HNSCC模型中的肿瘤上皮死亡和髓样细胞。不 将分析RT联合TGFβ/PD-L1抑制的细胞非依赖性治疗益处。目标3 将在局部复发和复发性患者中进行一项使用M7824（TGFβ/PD-L1双向抑制剂）的RT Ib期试验， 寡转移性HNSCC患者，并鉴定细胞和分子标志物作为治疗靶标。通过 进行拟议的研究，我们的目标是在真实的时间，同时 加强免疫治疗，降低预后不良的HNSCC患者的RT抵抗。此外，本发明还 确定拟议治疗的预测标志物将导致真正的生物标志物驱动的II期试验， 预先选定的患者。

SUMMARY, Project 2 Radiation therapy (RT) is commonly used for locally recurrent head and neck squamous cell carcinoma (HNSCCs), yet no standard concomitant systemic therapy exists, and RT resistance rates are high. Antibodies against programmed death-1 (PD-1) are FDA approved for treating relapsed/recurrent HNSCCs, but the response rate is low. RT induces anti-tumor immunity by causing DNA damage and tumor cell killing that release neoantigens to trigger an “in situ tumor vaccine” and activation of STING (stimulator of IFN genes) for local and systemic immune activation. Conversely, RT also induces transforming growth factor-β1 (TGFβ1), an immune suppressor, and PD-L1, a ligand of PD-1. These RT effects make dual TGFβ/PD-L1 inhibition a rational combination being tested in this project. We have reported that TGFβ1 is elevated in >60% of tobacco-associated HNSCCs. TGFβ1-mediated DNA repair contributes to RT resistance. TGFβ1 also contributes to RT-induced toxicity, e.g., oral mucositis and fibrosis. Using our mouse HNSCC models, we found that TGFβ/PD-L1 dual inhibition eradicated SCCs better than anti-PD-L1 alone in tumors with high TGFβ1 levels and high numbers of PD-L1+/CD11b+ cells. We also found that TGFβ inhibition reduced metastases in athymic mice correlated with reduced CD11b+ myeloid cells. We hypothesize that in advanced HNSCCs, TGFβ/PD-L1 dual inhibition enhances RT-induced in situ vaccination, reverses immune suppression, and overcome RT resistance via T cell-dependent and -independent mechanisms. We will test this hypothesis with experimental therapeutics, mechanistic studies and analyses of HNSCC patient specimens. Aim 1 will determine if TGFβ/PD- L1 dual inhibition enhances RT-induced in situ vaccination and systemic immune activation in oral SCC mouse models. Experimental therapeutics of RT plus TGFβ/PD-L1 dual inhibition will be performed using mouse SCC lines transplanted orthotopically to syngeneic mice, and T-cell dependent anti-tumor mechanisms will be analyzed at the cellular and molecular levels. Aim 2 will determine how RT regimens in combination with TGFβ/PD-L1 inhibition target tumor epithelial death and myeloid cells in mouse and human HNSCC models. T cell-independent therapeutic benefit of RT in combination with TGFβ/PD-L1 inhibition will be analyzed. Aim 3 will conduct a Phase Ib trial for RT with M7824 (TGFβ/PD-L1 bidirectional inhibitor) in locally recurrent and oligometastatic HNSCC patients and identify cellular and molecular markers as therapeutic targets. By performing the proposed studies, we aim to bring a therapeutic intervention in real time to simultaneously enhance immunotherapy and reduce RT resistance in HNSCC patients with poor prognosis. Additionally, identifying predictive markers to the proposed treatment will lead to a true biomarker-driven Phase II trial with pre-selected patients.