Targeting iNOS to inhibit myeloid-derived suppressor cells (MDSC) in melanoma

靶向 iNOS 抑制黑色素瘤中的骨髓源性抑制细胞 (MDSC)

• 批准号: 8189753
• 负责人: Andrew Sikora
• 金额: $ 13.49万
• 依托单位: ICAHN SCHOOL OF MEDICINE AT MOUNT SINAI
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-08-08 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8189753
• 关键词: Ablation; Address; Affect; Animals; Area; Biometry; Bone Marrow; CD8B1 gene; Cancer Biology; Cancer Immunology Science; Cancer Patient; Cell Count; Cell Culture System; Cell Differentiation process; Cells; Chemicals; Clinical Research; Clinical Trials; Critiques; Cutaneous Melanoma; Data; Data Analyses; Development; Development Plans; Down-Regulation; Environment; Enzymes; Experimental Designs; Funding; Generations; Genetic; Goals; Grant; Growth Factor; Homing; Human; ITGAM gene; Immune; Immune response; Immunization; Immunology; Immunosuppression; Immunosuppressive Agents; Immunotherapy; In Vitro; Individual; Infection; Infiltration; Inflammation; Inflammatory; Institution; Knockout Mice; Lead; Leukocytes; Lysine; Maintenance; Malignant Neoplasms; Mediating; Mediator of activation protein; Melanoma Cell; Mentors; Mentorship; Modeling; Molecular; Mus; Myelogenous; Myeloid Cells; Myeloproliferative disease; Natural Killer Cells; Nitric Oxide; Peptides; Physicians; Play; Production; Publications; Publishing; Recruitment Activity; Relative (related person); Research; Resistance; Role; STAT3 gene; Scientist; Secure; Serum; Shock; Skin Cancer; Solid Neoplasm; Spleen; Splenocyte; Suppressor-Effector T-Lymphocytes; T cell response; T-Lymphocyte; Testing; Transgenic Organisms; Translations; Vaccination; Vascular Endothelial Growth Factors; Work; Writing; base; cancer immunotherapy; career; career development; chemokine; clinical material; cytokine; design; experience; human NOS2A protein; improved; in vitro testing; inhibitor/antagonist; lymph nodes; meetings; melanoma; migration; mouse model; neoplastic cell; novel; novel strategies; patient population; programs; response; skills; small molecule; sound; trafficking; tumor; tumor progression; vaccine efficacy

DESCRIPTION (provided by applicant): Myeloid-derived suppressor cells (MDSC) are immature myeloid cells described in both tumor-bearing mice and human cancer patients, which play an increasingly recognized role in cancer maintenance, progression, and resistance to immunotherapy. MDSC infiltrate solid tumors, including coetaneous melanoma, and potently inhibit anti-tumor T cell responses through a variety of mechanisms including production of nitric oxide (NO) by inducible nitric oxide synthase (iNOS). While iNOS/NO have not previously been shown to regulate MDSC development, persistence, or localization within the tumor-bearing host, the well-known associations of iNOS with cancer, infection, shock, and other inflammatory states associated with MDSC accumulation make this an attractive hypothesis. Our preliminary data demonstrate that mice bearing syngeneic B16 or MT-RET melanomas accumulate splenic and tumor-infiltrating GR-1+CD11b+ MDSC, and experience a decline in splenic CD4+ and CD8+ T cells. Treatment with the small molecule iNOS inhibitor N6(1-iminoethyl)-L-lysine-dihydrochloride (L-NIL) decreases MDSC infiltration in tumor and spleen, reverses the tumor-mediated decrease in CD4+ and CD8+ splenocytes, and enhances the number of tumor-infiltrating CD4+ and CD8+ T cells. L-nil treatment was also associated with down regulation of activated STAT3 in the tumor, and normalization of elevated levels of VEGF and other inflammatory cytokines observed in sera of tumor-bearing mice. Serum VEGF levels were also suppressed, intratumoral MDSC infiltration reduced, and T cell numbers normalized in tumor-bearing iNOS-/- "knockout" mice, suggesting that host-derived iNOS plays a role in MDSC recruitment and migration. Together, these data suggest that MDSC recruitment and trafficking are controlled by cross-talk in which iNOS expression by tumor-infiltrating myeloid cells, melanoma cells, or both is required for release of soluble factors from the tumor which recruit additional MDSC from the bone marrow and drive their infiltration into the tumor. We further hypothesize that targeted inhibition of iNOS with small-molecule chemical antagonists will enhance the response to anti-tumor vaccination by suppressing the recruitment and suppressive capacity of intratumoral MDSC. In this proposal we aim to characterize the effect of iNOS inhibition on tumor-secreted factors responsible for recruitment and intratumoral homing of MDSC in syngeneic transplantable and spontaneous tumor models. We will seek to determine whether the effects of iNOS inhibition on production, by tumor and myeloid cells, of cytokines known to regulate MDSC are mediated by changes in STAT3 activation. We will determine whether iNOS inhibition decreases intratumoral MDSC numbers by affecting their trafficking, survival, or differentiation, or through a combination of these mechanisms. Finally, we will use a well-established model of adoptive CD8+ T cell transfer and anti-tumor vaccination to determine whether targeted iNOS inhibition boosts the number, effector function, and anti-tumor efficacy of vaccine-induced CD8+ CTL. The above project will be carried out in the context of a comprehensive, mentored career development plan leading to scientific independence. A team of outstanding mentors will provide critical guidance in every aspect of the candidate's scientific development, from hands-on critique of experimental design and data analysis, to publication of results, to acquisition of lab management and grant-writing skills which will lead to independent funding. These personal interactions will be supplemented by formal class work addressing specific areas targeted for improvement (biostatistics, clinical research skills and translation of basic findings to clinical trials). As the candidate is a physician-scientist with access to unique patient populations and clinical material, special emphasis has been placed on providing didactic background and supplemental mentorship in clinical research. The candidate has the benefit of a first class research environment in which immunology and cancer biology are centers of excellence within the institution, and already has secured the confidence and support of his department and the institution. His immediate goal of carrying out and publishing the research proposed in this application will significantly enhance our understanding of the relationship between inflammation and tumor-mediated immunosuppression, and provide a sound platform for establishing an independent research career in cancer immunology and translational cancer biology. PUBLIC HEALTH RELEVANCE: Once mechanism used by cancers to shield themselves from immune responses is to induce the generation of so-called "myeloid-derived suppressor cells" (MDSC) which are white blood cells that suppress anti-tumor T cell responses. We have discovered that, by blocking the activity or expression of one of the body's inflammatory molecules - the enzyme inducible nitric oxide synthase (iNOS), it is possible to inhibit the accumulation and immune-suppressing activity of MDSC in a mouse model of melanoma (skin cancer); these finding s may ultimately be used to improve cancer immunotherapy. The written critiques and criteria scores of individual reviewers are provided in essentially unedited form in the "Critique" section below. Please note that these critiques and criteria scores were prepared prior to the meeting and may not have been revised subsequent to any discussions at the review meeting. The "Resume and Summary of Discussion" section above summarizes the final opinions of the committee.

描述（由申请人提供）：髓源性抑制细胞（myeloid -derived suppressor cells， MDSC）是在肿瘤小鼠和人类癌症患者中发现的未成熟髓系细胞，在癌症维持、进展和免疫治疗抵抗中发挥着越来越多的作用。MDSC浸润实体肿瘤，包括同期黑色素瘤，并通过多种机制，包括诱导型一氧化氮合酶（iNOS）产生一氧化氮（NO），有效抑制抗肿瘤T细胞反应。虽然iNOS/NO先前未被证明调节MDSC在肿瘤宿主内的发育、持续或定位，但众所周知，iNOS与癌症、感染、休克和其他与MDSC积累相关的炎症状态之间存在关联，因此这是一个有吸引力的假设。我们的初步数据表明，携带同源B16或MT-RET黑色素瘤的小鼠在脾脏和肿瘤浸润的GR-1+CD11b+ MDSC中积聚，并经历脾脏CD4+和CD8+ T细胞的下降。用小分子iNOS抑制剂N6（1-亚氨基乙基）- l -赖氨酸二盐酸（L-NIL）治疗可减少肿瘤和脾脏的MDSC浸润，逆转肿瘤介导的CD4+和CD8+脾细胞减少，并增加肿瘤浸润的CD4+和CD8+ T细胞的数量。L-nil治疗还与肿瘤中活化STAT3的下调有关，并且在荷瘤小鼠血清中观察到VEGF和其他炎症细胞因子水平升高的正常化。在携带iNOS-/-“敲除”的小鼠中，血清VEGF水平也受到抑制，瘤内MDSC浸润减少，T细胞数量正常化，表明宿主来源的iNOS在MDSC募集和迁移中发挥作用。综上所述，这些数据表明，MDSC的募集和运输是由串扰控制的，在串扰中，肿瘤浸润的骨髓细胞、黑色素瘤细胞或两者都需要iNOS的表达，才能从肿瘤中释放可溶性因子，从而从骨髓中募集更多的MDSC，并驱使它们浸润到肿瘤中。我们进一步假设，用小分子化学拮抗剂靶向抑制iNOS将通过抑制肿瘤内MDSC的募集和抑制能力来增强对抗肿瘤疫苗的应答。在本研究中，我们旨在研究iNOS抑制对同基因可移植和自发肿瘤模型中负责MDSC募集和瘤内归巢的肿瘤分泌因子的影响。我们将试图确定iNOS抑制肿瘤和髓细胞产生的已知调节MDSC的细胞因子的影响是否通过STAT3激活的变化介导。我们将确定iNOS抑制是否通过影响肿瘤内MDSC的贩运、存活或分化，或通过这些机制的组合来减少肿瘤内MDSC的数量。最后，我们将使用一个成熟的过继性CD8+ T细胞转移和抗肿瘤疫苗模型来确定靶向iNOS抑制是否会提高疫苗诱导的CD8+ CTL的数量、效应物功能和抗肿瘤功效。上述项目将在一个全面的、有指导的职业发展计划的背景下进行，以实现科学独立。优秀的导师团队将在候选人科学发展的各个方面提供重要的指导，从实验设计和数据分析的实践批评，到结果的发表，再到获得实验室管理和资助撰写技能，这些技能将导致独立资助。这些个人互动将被正式的课堂作业所补充，这些作业针对的是需要改进的特定领域（生物统计学、临床研究技能和将基本发现转化为临床试验）。由于候选人是一名医师兼科学家，可以接触到独特的患者群体和临床材料，因此特别强调在临床研究中提供教学背景和补充指导。该候选人拥有一流的研究环境，其中免疫学和癌症生物学是该机构的卓越中心，并且已经获得了他所在部门和该机构的信任和支持。他的近期目标是开展和发表本申请中提出的研究，这将大大增强我们对炎症与肿瘤介导的免疫抑制之间关系的理解，并为建立癌症免疫学和转化癌症生物学的独立研究事业提供良好的平台。