Combination immunotherapy for neuroblastoma: model of innate tumor immunity

描述（由申请人提供）：神经母细胞瘤（NB）是儿童最常见的颅外实体瘤。虽然强化诱导化疗和积极的手术提高了年轻患者的缓解率，但在老年患者和40%的化疗耐药NB患者中，结果并不令人印象深刻。在诊断时年龄> 18个月的儿童中，转移性NB的长期无复发生存率仅为~ 20%。这些令人失望的结果是追求新的治疗方法的令人信服的理由。一种成功的替代方法是使用3F 8进行免疫治疗，3F 8是一种针对NB细胞上普遍存在的GD 2糖脂抗原的鼠IgG 3单克隆抗体。虽然3F 8给药对缓解期NB患者具有明显的生存获益，但对软组织耐药NB患者或疾病进展患者无效。这可能部分是由于其依赖于抗体依赖性细胞介导的细胞毒性（ADCC），后者主要由自然杀伤（NK）细胞介导，其在大量预治疗的患者中耗尽。从健康的同种异体来源连续转移NK细胞可能会恢复和增强这些低风险患者的3F 8效应。 自然杀伤（NK）细胞是具有通过多种途径（包括通过与CD 16 Fc受体结合的ADCC）发挥抗肿瘤活性的能力的淋巴细胞。然而，NK细胞的细胞毒性应答的能力由其细胞表面受体决定，特别是对sel-MHC I类分子特异性的抑制性和活化性免疫球蛋白样受体（KIR）。为了使过继转移的NK细胞的效果最大化，应该选择最有可能产生NK同种异体反应性和实现最高功能性NK应答的供体。这可以通过基于供体和患者的HLA和KIR基因型选择供体并通过使用可以反映体内肿瘤MHC环境的体外系统评估NK功能来实现。在该提案的第一个目标中，我们提出，肿瘤上MHC I类分子的上调选择性地抑制正常反应的NK群体，使正常功能低下的“无执照”NK群体介导患者的ADCC。抗体治疗期间产生的炎性细胞因子也可能增强未经许可的NK活性。未经许可的NK细胞群体的活性可能很重要，在选择NK供体进行过继转移时应予以考虑。 该提案提出了一种新的免疫治疗方法，用于治疗高危神经母细胞瘤。3F 8单克隆抗体与从适当选择的供体过继转移的NK细胞的组合应增加ADCC、抗体效力和肿瘤根除。由于这些免疫学方法从未在实体瘤或儿科人群中进行过联合研究，因此有必要进行I期研究，以检查3F 8与递增剂量的NK细胞联合使用的安全性，这是该提案的第二个目的。介绍了NK和3F 8治疗的潜在毒性、毒性监测计划、剂量递增计划、预期结局和停止规则。供-受者KIR/HLA免疫遗传学和供者FcR多态性将与NK细胞活化和体外抗NB靶细胞的细胞毒作用相关。安全性和可行性论证 将过继转移的NK细胞与单克隆抗体组合不仅将导致对预后差的NB患者的更有效的治疗方法，而且将广泛适用于目前用单克隆抗体治疗的其它癌症群体，例如淋巴瘤和乳腺癌。将供体-受体KIR/HLA效应与结果相关联将澄清供体优先算法，并为未来NK免疫治疗研究提供预后价值。 公共卫生相关性：自然杀伤（NK）细胞是人体免疫系统的重要组成部分，保护个体免受癌症的侵袭。该提案旨在帮助医生使用NK细胞和免疫系统治疗儿童神经母细胞瘤（一种儿童癌症）。这项研究的结果将为其他可能被NK细胞杀死的癌症提供信息。

DESCRIPTION (provided by applicant): Neuroblastoma (NB) is the most common extracranial solid tumor of childhood. While intensive induction chemotherapy and aggressive surgery have improved remission rates in young patients, results have been less impressive in older patients and in the 40% of patients with chemo resistant NB. Metastatic NB in children > 18 months of age at diagnosis carries a long-term relapse-free survival of only ~20%. These disappointing results are compelling reasons for pursuing novel therapeutic approaches. One successful alternative approach has been immunotherapy with 3F8, a murine IgG3 monoclonal antibody to the GD2 glycolipid antigen ubiquitously present on NB cells. While 3F8 administration confers a clear survival benefit to NB patients in remission, it is not effective for patients with resistantsoft tissue NB or patients with progressive disease. This may be due in part to its dependence on antibody- dependent cell-mediated cytotoxicity (ADCC), the latter mediated largely by natural killer (NK) cells, which are depleted in heavily pre-treated patients. Adoptive transfer of NK cell from a healthy allogeneic source may restore and enhance 3F8 effects in these poor-risk patients. Natural killer (NK) cells are lymphocytes that have the capacity for antitumor activity via multiple pathways, including ADCC through engagement of the CD16 Fc receptor. The capacity of an NK cell for cytotoxic response, however, is dictated by its cell surface receptors, specifically the inhibitory and activating killer-Ig like receptors (KIR) that are specific for sel-MHC class I molecules. To maximize the effects of adoptively transferred NK cells, one should select donors from whom there is the greatest likelihood of engendering NK alloreactivity and of achieving highest functional NK response. This can be accomplished by selecting donors based on the HLA and KIR genotypes of the donor and the patient and by evaluating NK function using an in vitro system that may reflect the tumor MHC environment in vivo. In the first aim of the proposal, we propose that up regulation of MHC class I molecules on the tumor selectively inhibits normally responsive NK populations, leaving the normally hypofunctional, "unlicensed" NK population to mediate ADCC in patients. Inflammatory cytokines elaborated during antibody therapy may also enhance unlicensed NK activity. The activity of the unlicensed NK population can be significant and should be considered when selecting an NK donor for adoptive transfer. This proposal presents a novel immunotherapeutic approach for the treatment of high-risk neuroblastoma. Combination of 3F8 monoclonal antibody with adoptively transferred NK cells from appropriately selected donors should increase ADCC, antibody efficacy, and tumor eradication. Because these immunologic approaches have never been studied in combination for a solid tumor or in the pediatric population, a phase I study to examine the safety of 3F8 combined with escalating doses of NK cells is necessary and represents the second aim of the proposal. Potential toxicities of NK and 3F8 therapies, a toxicity monitoring plan, dose escalation plan, the expected outcome and stopping rules are presented. Donor-recipient KIR/HLA immunogenetics and donor FcR polymorphism will be correlated with NK activation and cytotoxic function against NB target cells in vitro. Demonstration of safety and feasibility of combining adoptively transferred NK cells with monoclonal antibody will not only result in a more potent therapeutic approach for poor-prognosis NB patients, but will be broadly applicable to other cancer populations such as lymphoma and breast carcinoma currently treated with monoclonal antibodies. Correlating donor-recipient KIR/HLA effects with outcome will clarify donor prioritization algorithms and provide prognostic value for future NK immunotherapy studies. PUBLIC HEALTH RELEVANCE: Natural killer (NK) cells are a vital component of the body's immune system, protecting the individual from developing cancer. This proposal is designed to help physicians use NK cells and the immune system as treatment for children with neuroblastoma, a childhood cancer. Findings from this study will be informative for other cancers that may also be killed by NK cells.