Transcriptional and Epigenetic Adaptation as Novel Therapeutic Vulnerabilities for Mantle Cell Lymphoma

转录和表观遗传适应作为套细胞淋巴瘤的新治疗漏洞

• 批准号: 9885341
• 负责人: Jun QI
• 金额: $ 51.34万
• 依托单位: H. LEE MOFFITT CANCER CTR & RES INST
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-03-01 至 2025-02-28
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/9885341
• 关键词: Atlases; B lymphoid malignancy; B-Cell Lymphomas; BCL1 Oncogene; BCL2 gene; Back; Biological Assay; Biology; Cell Line; Cell Survival; Cells; ChIP-seq; Chemicals; Chromatin; Clinical; Clinical Trials; Collaborations; Combined Modality Therapy; Complex; Development; Disease; Disease Progression; Drug Modelings; Drug Screening; Drug Targeting; Drug Tolerance; Drug resistance; Effectiveness; Enhancers; Epigenetic Process; Evolution; FDA approved; Genetic; Genetic Transcription; Growth; Hematopoietic Neoplasms; Heterogeneity; Human; Immunoprecipitation; Institution; Joints; Laboratories; Lymphoma; Lymphoma cell; Malignant Neoplasms; Mantle Cell Lymphoma; Mediating; Modeling; Molecular; Mus; Nature; Pathway interactions; Patients; Pharmaceutical Preparations; Population; Protein Family; Publishing; Qi; Relapse; Resistance; Resistance development; Resources; STAT3 gene; Sampling; Sampling Studies; Signal Pathway; Technology; Therapeutic; Translations; Treatment Efficacy; Up-Regulation; Validation; Work; Xenograft Model; Xenograft procedure; acquired drug resistance; attenuation; base; chromatin remodeling; clinical remission; clinical translation; combat; combinatorial; drug development; drug-sensitive; effective therapy; experience; improved; improved outcome; in vivo; in vivo Model; inhibitor/antagonist; insight; lymphoid organ; mortality; novel; novel therapeutics; outcome forecast; pre-clinical; preclinical study; pressure; prevent; relapse patients; resistance mechanism; response; small molecule; standard care; targeted cancer therapy; tool; transcriptome; transcriptome sequencing

Acquired drug resistance (DR) largely limits the effectiveness of targeted cancer therapies, especially for aggressive diseases, such as mantle cell lymphoma (MCL), a B-cell lymphoma with poor prognosis. Recently, FDA approved drug Venetoclax (ABT-199), a novel, potent and selective small-molecule BCL-2 inhibitor was clinically vetted as an effective therapy for hematopoietic tumors, including MCL. The use of ABT-199 produced a dramatic response; however, the emergence of resistance to this drug was ensued by fatal progression of the MCL. Once MCL patients relapse from ABT-199 treatment, either during or after, there is rapid disease progression and accelerated mortality. Thus, there is an urgent need to define mechanisms of ABT-199 resistance (AR) and identify targets to bring forward novel treatment options with tangible curative potential. We modeled drug resistance to ABT-199 by generating AR cell lines from MCL, and characterized the adaptive molecular reprogramming to ABT-199 treatment in these cells. Small subpopulations of lymphoma cells were consistently detected that evade strong selective ABT-199 pressure by entering a reversible drug tolerant 'persister' state (DTP), and consequently leading to a DTP expansion population (DTEP) and eventual acquisition of bona fide drug resistance. Given the premise that a myriad of mechanisms are involved in MCL AR, we applied network-wide, robust and unbiased approaches to determine the major altered MCL signaling pathways during AR evolution. More complex and more dynamic than we had anticipated, we observed that these DTEP cells conferred increased viability and clonogenic growth, associated with BH3 family protein reprogramming. Intriguingly, DTEP cells can revert back to drug sensitive states after long-term passaging without the drug, supporting the notion that these cells are epigenetically reprogrammed to drug resistant states. Consistent with these results, our initial drug screen revealed the exquisite sensitivity to epigenetic machinery inhibitors (e.g., BRD4, CDK7) in ABT-199 DTEP cells when compared with parental cells. In line with this, our immunoprecipitation-sequencing (ChIP-Seq) and RNA-Seq assays revealed dynamic super enhancer (SE) remodeling in DTEP MCL cells, and this chromatin alteration is associated with CDK7-mediated transcription in ABT-199 resistant MCL cells. We propose that transcriptional and epigenetic adaptive responses are required for the survival of cells that persist in the presence of ABT-199 therapy. The objective of this proposal is to strategically target transcriptional machinery and provide pre-clinical validation by targeting CDK7/BRD4, in combination with BCL-2 as an efficient and durable treatment for MCL. With the small molecule tools for epigenetic targets and patient-derived xenograft (PDX) model available in the Qi and Tao laboratories, respective expertise and the unique access to a large resource of primary MCL samples, the study allows us to gain valuable insights into MCL drug resistance biology and uncover a novel mechanism- driven therapy for MCL patients.

获得性耐药（DR）在很大程度上限制了靶向癌症治疗的有效性，特别是对于