(PQ#3) Novel tumor intrinsic PD-L1 signals direct tumor immune cell infiltration

（PQ

• 批准号: 9926828
• 负责人: Tyler J. Curiel
• 金额: $ 64.05万
• 依托单位: UNIVERSITY OF TEXAS HLTH SCIENCE CENTER
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-06-01 至 2022-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9926828
• 关键词: Affect; Autologous; Cell Proliferation; Cell surface; Cells; Cellular biology; Clinical; Clustered Regularly Interspaced Short Palindromic Repeats; Complement; Cytoplasm; Data; Defect; Engineering; FDA approved; FRAP1 gene; Funding; Genes; Growth; Human; Immune; Immune response; Immunology; Immunotherapy; In Vitro; Infiltration; Inflammatory Infiltrate; Joints; Knock-out; Knowledge; Lead; Malignant Neoplasms; Malignant neoplasm of urinary bladder; Mediating; Melanoma Cell; Modality; Modeling; Molecular Medicine; Mus; Mutate; Mutation; Outcome; PD-1/PD-L1; Pathway interactions; Patient-Focused Outcomes; Patients; Pharmacotherapy; Positioning Attribute; Pre-Clinical Model; Prediction of Response to Therapy; Publications; Reagent; Regulation; Research; Research Personnel; Resistance; Signal Transduction; Site; Skin graft; Study models; Surface; T-Lymphocyte; Testing; Transplantation; Treatment outcome; Tumor Cell Line; Tumor Escape; Tumor Immunity; Tumor-infiltrating immune cells; Validation; anti-PD-1; anti-PD-L1; anti-PD-L1 antibodies; base; cancer therapy; chemokine; clinical translation; follow-up; human tissue; humanized mouse; immune clearance; improved; in vivo; inhibitor/antagonist; insight; knock-down; mTOR Inhibitor; melanoma; mouse model; neoplasm immunotherapy; neoplastic cell; novel; novel marker; predicting response; programmed cell death ligand 1; programmed cell death protein 1; response; small hairpin RNA; success; trafficking; transcriptome sequencing; treatment effect; treatment response; tumor; tumor growth; tumor immunology; tumor microenvironment; tumor progression; vector

We respond to PQ3 with our data showing that tumor PD-L1 (CD274, B7-H1) is a major regulator of tumor inflammatory infiltrates. Our preliminary data show that melanoma PD-L1 regulates TIL through several previously unknown tumor-intrinsic and extrinsic mechanisms. We define novel effects of tumor intrinsic PD-L1 signaling on tumor proliferation, sensitivity to immune killing, in vivo growth independent of anti-tumor immunity, and regulation of mTOR signals. We identified intracellular PD-L1, including those whose surface expression is low or negative, and identified interactions with tumor PD-1. We hypothesize that melanoma intrinsic PD-L1-driven signals, particularly mTOR signals, alter tumor progression and treatment responses. The research team is comprised of tumor immunotherapy, tumor immunology and PD-L1 experts at UTHSCSA and Dartmouth. We focus on melanoma for scientific reasons and based on our expertise. Aim 1 Define how tumor PD-L1 alters tumor immune infiltrates and immunotherapy responses. We use control versus PD-L1lo (shRNA) B16 in a novel model to study differential treatment outcomes by tumor PD-L1 status. We generated PD-L1KO B16 by CRISPR for highly detailed follow up mechanistic studies, and to assess if PD-L1 null status differentially affects treatment versus PD-L1lo. Effects will also be tested in transplanted BrafV600E mutated D4M melanoma (PD-L1+) engineered to be PD-L1lo and PD-L1KO, in mice with induced BrafV600E melanomas, and in syngeneic skin grafts of skin from Braf/Pten versus PD-L1KO Braf/Pten mice. Aim 2 Test tumor PD-L1-driven mTOR signal effects on TIL and immunotherapy responses. We will test PD-L1 KO, PD-1 KO and double KO melanoma cells for mTOR signals, TIL and treatment effects. Cells will be engineered for defects in mTORC1/2 for mechanistic studies, complemented with mTOR inhibitor treatments. We will use engineered tumors that express cytoplasm-only versus cell surface-only PD-L1, to define novel, intracellular PD-L1 signals. Constructs with mutations in known PD-1 signal sites will be engineered into these tumors for a complete understanding of PD-L1/PD-1 interactions. Aim 3 Define cell-intrinsic PD-L1 effects in human melanoma. We use well-defined human melanoma lines that are basal PD-L1+ and/or PD-1+ and/or BrafV600E mutated. We will use human vectors to knock down or knock out PD-L1, PD-1 and mTORC1/2 genes. In vitro assessments of effects on proliferation, responses to mTOR inhibitors, αPD-L1 and αPD-1 will be assessed. In vivo effects in NSG mice will be assessed. Primary human melanoma lines will be studied to complement data from long-term lines.

我们的数据显示肿瘤PD-L1 （CD274, B7-H1）是肿瘤的主要调节因子