Epigenetic Regulation of Drug Resistance to ABT-199 in B-cell Malignancies

B 细胞恶性肿瘤中 ABT-199 耐药性的表观遗传调控

• 批准号: 9904591
• 负责人: John L. Cleveland
• 金额: $ 18.71万
• 依托单位: H. LEE MOFFITT CANCER CTR & RES INST
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-04-01 至 2022-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9904591
• 关键词: Attention; B lymphoid malignancy; BCL2 gene; Back; Biology; Cell Line; Cells; ChIP-seq; Clinical; Clonal Evolution; Complex; Disease Resistance; Drug Modelings; Drug Targeting; Drug Tolerance; Drug resistance; EP300 gene; Enhancers; Epigenetic Process; Event; Evolution; Genetic Transcription; Goals; Growth; Hematopoietic Neoplasms; Histone H3; Laboratories; Lymphoma; Lymphoma cell; Lysine; Mantle Cell Lymphoma; Molecular; Patients; Pharmaceutical Preparations; Pharmacotherapy; Phase; Population; Protein Family; Residual Neoplasm; Resistance; Resources; Role; Sampling; Supporting Cell; Technology; Testing; Therapeutic; Transcript; Transcription Elongation; Validation; Xenograft procedure; clinical translation; drug use screening; drug-sensitive; effective therapy; epigenetic regulation; improved; in vivo; in vivo Model; inhibitor/antagonist; insight; novel; outcome forecast; pre-clinical; pressure; prevent; response; small molecule; targeted treatment; transcriptome; transcriptome sequencing

While enormous effort has gone into understanding the molecular events in acquired resistance, not much attention has been given to what happens during treatment, particularly during the early phase when patients still respond to drug treatment. Venetoclax (ABT-199), a novel potent and selective small-molecule BCL-2 inhibitor, has recently emerged as an effective therapy for hematopoietic tumors including MCL. While responses to ABT-199 can often be dramatic, they are rarely durable, and there is a significant need to improve the duration of response and delay or prevent drug resistance (DR). We modeled drug resistance to ABT-199 by generating ABT-199 resistant cell lines from MCL, and characterized the adaptive molecular reprogramming to ABT-199 treatment in MCL lines and primary samples. More complex and more dynamic than we had anticipated, we consistently detected a small subpopulations of lymphoma cells that evade strong selective ABT-199 pressure by entering a reversible drug tolerant 'persister' state (DTP), leading to DTP expansion population (DTEP) and eventual acquisition of bona fide drug resistance. We observed that these DTEP cells are conferred increased survival, clonogenic growth and are associated with BH3 family protein reprogramming. Intriguingly, DTEP cells revert back to drug sensitive states after long term passage without the drug, supporting that these cells are epigenetically reprogrammed to drug resistant states. Consistent with these results, by using drug screen approaches, we observed that epigenetic regulators such as BRD4, PRMT5, CDK9 and EP300 are required for and contribute to drug tolerance and drug resistance evolution. Most recently, RNA sequencing (RNA-seq) and ChIP-seq against H3K27Acrevealed super-enhancers (SE) remodeling in DTEP cells, supporting that epigenetically regulated SEs remodeling is required for transcriptional reprogramming and drug resistance evolution. Our central hypothesis is that transcriptional and epigenetic adaptive response and coordination in response to ABT-199 treatment confer MCL drug tolerance and therapeutic vulnerability to prevent subsequent drug resistance evolution in MCL. The objective of this proposal is to strategically target epigenetic transcription machinery and provide pre-clinical validation of combination of epigenetically targeting with BCL-2 antagonist as a therapeutic approach against MCL. The study allows us to gain valuable insights into MCL drug resistance biology and uncover a novel mechanism- driven therapy for MCL patients.

虽然巨大的努力已努力理解获得的抗性中的分子事件，但并不多 注意治疗过程中发生的情况，尤其是在患者的早期 仍然对药物治疗做出反应。 Venetoclax（ABT-199），一种新颖的有效和选择性的小分子Bcl-2 抑制剂最近已成为包括MCL在内的造血肿瘤的有效疗法。尽管 对ABT-199的反应通常是戏剧性的，它们很少耐用，而且很有必要 改善反应持续时间和延迟或预防耐药性（DR）。我们对耐药性建模为 ABT-199通过从MCL产生ABT-199抗性细胞系，并表征自适应分子 重新编程，以在MCL系和主要样品中进行ABT-199治疗。更复杂，更动态 比我们预期的是，我们始终检测到一个较小的淋巴瘤细胞亚群，这些细胞逃避了强大 选择性ABT-199压力通过进入可逆的药物耐受性“持久”状态（DTP），导致DTP 扩张人群（DTEP）和最终获得真正的耐药性。我们观察到这些 授予DTEP细胞的生存率增加，克隆生长生长，并与BH3家族蛋白有关 重新编程。有趣的是，长期通过后，DTEP细胞恢复回到药物敏感状态 该药物支持这些细胞在表观遗传上重编程为耐药态。与 这些结果，通过使用药物筛查方法，我们观察到表观遗传调节剂，例如BRD4， PRMT5，CDK9和EP300是必需的，并有助于药物耐受性和耐药性演化。 最近，针对H3K27ACREVEALED超级增强剂（SE）的RNA测序（RNA-SEQ）和CHIP-SEQ 在DTEP细胞中进行重塑，支持表观遗传调节的SES重塑。 转录重编程和耐药性演变。我们的中心假设是转录和 对ABT-199治疗赋予MCL药物耐受性的表观遗传自适应反应和协调 和治疗性脆弱性，以防止MCL中随后的耐药性演变。这个目的 建议是在战略上针对表观遗传转录机制，并提供临床前验证 与Bcl-2拮抗剂作为对MCL的治疗方法的表观遗传靶向的组合。这 研究使我们能够获得对MCL耐药性生物学的宝贵见解，并发现一种新型机制 - MCL患者的驱动疗法。