Harnessing double stranded-RNA (dsRNA)-response and anti-tumor effect in PRC2-inactivated cancer

利用双链 RNA (dsRNA) 反应和 PRC2 失活癌症的抗肿瘤作用

• 批准号: 10638759
• 负责人: Ping Chi
• 金额: $ 74.5万
• 依托单位: SLOAN-KETTERING INST CAN RESEARCH
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-03-22 至 2028-02-29
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10638759
• 关键词: Alleles; Antitumor Response; Autophagocytosis; Biochemical; C57BL/6 Mouse; Cancer Model; Cells; Chromatin Structure; Clinical Trials; Complex; DNA Modification Methylases; Data; Decitabine; Development; Double-Stranded RNA; EZH2 gene; Engineering; Engraftment; Evaluation; Evolution; Future; Generations; Genetic; Genetic Transcription; Genome; Goals; High Prevalence; Histone H3; IRF3 gene; Immune; Immune response; Immunocompetent; Immunologic Cytotoxicity; Immunotherapy; In Vitro; Individual; Infection; Innate Immune Response; Lysine; Malignant Neoplasms; Mammary Neoplasms; Mediating; Modeling; Molecular; Mus; NF-kappa B; Neurofibrosarcoma; Outcome; Phenotype; Polycomb; Recombinant modified vaccinia virus Ankara; Resistance; Retrotransposon; Role; Signal Pathway; Signal Transduction; Soft tissue sarcoma; System; Therapeutic; Transcriptional Activation; Tumor Suppressor Proteins; Virus; Work; antitumor effect; biomarker driven; cancer cell; cancer type; cytotoxic; cytotoxicity; demethylation; design; effective therapy; epigenome; histone methylation; immune checkpoint blockade; immunogenic; immunogenicity; improved outcome; in vivo; inhibitor; innovation; insight; knock-down; melanoma; mouse model; multiple omics; neoplastic cell; novel; novel therapeutic intervention; pre-clinical; response; sensor; single-cell RNA sequencing; stemness; stress granule; transcriptome; treatment effect; tumor; tumor growth; tumor heterogeneity; tumor microenvironment

PROJECT SUMMARY/ABSTRACT: The polycomb repressive complex 2 (PRC2) complex establishes and maintains di- and tri-methylation of the histone H3 at lysine 27 (H3K27me2/3) in the genome and regulates chromatin structure, transcription, cellular stemness and differentiation. PRC2 is a context-dependent tumor suppressor whose core components (e.g., EZH2, EED, or SUZ12) are inactivated in various cancer types. Among these, high-grade malignant peripheral nerve sheath tumor (MPNST), an aggressive soft tissue sarcoma with no effective therapies, has a high prevalence (≥80%) of biallelic inactivation of EED or SUZ12, leading to complete loss of the PRC2 function. PRC2 loss in cancer results in aberrant transcriptional activation of developmentally silenced master regulators, which leads to enhanced cellular plasticity and aberrant activation of multiple signaling pathways. We recently uncovered that PRC2 loss in cancer leads to an immune-desert tumor microenvironment and resistance to immune checkpoint blockade. Nevertheless, we observed that, in murine models of PRC2-loss MPNST and mammary tumors, response to immunotherapy can be enhanced by infection with immunogenic virus, which activates double-stranded RNA (dsRNA) signaling responses. Moreover, we have identified and validated a lethal interaction between PRC2 loss and DNA methyltransferase 1 (DNMT1) knockdown in MPNST. In vitro and in vivo treatment with a demethylating agent (decitabine) or selective DNMT1 inhibitors (GSK862, GSK032) led to enhanced cytotoxicity and antitumor effects in PRC2-loss compared to PRC2 wild-type (wt) MPNST models. Mechanistically, DNMT inhibitor (DNMTi) treatment in the PRC2-loss context amplified the expression of endogenous retrotransposons and subsequently led to activation of innate immune responses, which could be explained by retrotransposons forming dsRNA and triggering cytotoxicity via PKR-dependent dsRNA sensing. we hypothesize that PRC2 loss in cancer may create therapeutic opportunities for agents (e.g., DNMTi, synthetic dsRNA, immunogenic viruses) that activate the dsRNA signaling pathways in tumor cells to induce cytotoxicity and enhance immunogenicity. Here, we propose integrative multi-omics analysis (e.g., transcriptome, epigenome, single-cell [sc]RNA-seq and scATAC-seq) and innovative approaches (e.g., novel immunogenic viruses, a novel lineage-tracking system) to evaluate novel therapeutic strategies and their mechanisms of activating dsRNA responses and anti-tumor effects in relevant PRC2-loss cancers, focusing on specific aims: (1) dissect the molecular mechanisms that underlie the selective sensitivity to DNMTi in different PRC2-loss cancers; (2) evaluate exogenous dsRNAs as a strategy to induce cytotoxicity in PRC2-loss tumors; and (3) evaluate novel therapeutic strategies of activating dsRNA-responses in relevant cancer models. These studies will generate insights into exploiting dsRNA-sensing and activation of innate immune responses as therapeutic strategies in PRC2-loss cancers and provide the pivotal preclinical data for biomarker-driven clinical trials.

项目摘要/摘要： 多孔反射复合物2（PRC2）复合物建立并维持了二甲基和三甲基化 基因组中的赖氨酸27（H3K27ME2/3）的Hisstone H3，调节染色质结构，转录，细胞 干与分化。 PRC2是一种依赖上下文的肿瘤抑制因子，其核心成分（例如， EZH2，EED或SUZ12）在各种癌症类型中被灭活。其中，高级恶性外围 神经鞘肿瘤（MPNST）是一种没有有效疗法的侵略性软组织肉瘤，具有高度 EED或SUZ12的生物灭活率（≥80％），导致PRC2功能的完全丧失。 癌症中的PRC2损失导致形成的转录激活的发展为沉默的主调节剂， 这导致了增强的细胞可塑性和多个信号通路的异常激活。我们最近 发现癌症中的PRC2丧失会导致免疫疾病的肿瘤微环境和对 免疫检查点封锁。然而，我们观察到，在Prc2-loss mpnst的鼠模型中 通过免疫原性病毒感染可以增强乳腺肿瘤，对免疫疗法的反应，这可以增强。 激活双链RNA（DSRNA）信号反应。此外，我们已经确定并验证了 MPNST中PRC2损失与DNA甲基转移酶1（DNMT1）敲低的致命相互作用。体外和 用脱甲基剂（Decitabine）或选择性DNMT1抑制剂（GSK862，GSK032）LED进行体内治疗 与PRC2野生型（WT）MPNST模型相比，PRC2损伤中的细胞毒性和抗肿瘤作用增强。 从机械上讲，DNMT抑制剂（DNMTI）在PRC2损坏环境中的处理扩大了表达 内源性逆转座子，随后导致了先天免疫调查的激活，这可能是 通过逆转座子来解释，形成dsRNA并通过依赖PKR依赖性dsRNA感应触发细胞毒性。 我们假设癌症中的PRC2损失可能会为药物创造治疗机会（例如DNMTI，合成 DSRNA，免疫原性病毒）激活肿瘤细胞中DSRNA信号通路以诱导细胞毒性 并增强免疫原性。在这里，我们提出了综合的多词分析（例如，转录组， 表观基因组，单细胞[SC] RNA-SEQ和SCATAC-SEQ）和创新方法（例如，新型免疫原性 病毒，一种新型的谱系跟踪系统），以评估新颖的理论策略及其机制 激活DSRNA反应和相关PRC2损伤癌中的抗肿瘤效应，重点关注特定目的： （1）剖析对不同PRC2-alss中选择性敏感性的分子机制 癌症； （2）评估外源性DSRNA作为诱导PRC2损伤肿瘤细胞毒性的策略； （3） 评估在相关癌症模型中激活dsRNA-响应的新型治疗策略。这些研究 将产生有关利用dsRNA感应和先天免疫反应的激活作为治疗的见解 PRC2损害癌的策略，并为生物标志物驱动的临床试验提供关键的临床前数据。