Elucidating the epigenetic mechanism of melanoma dedifferentiation in response to pro-inflammatory cytokines

阐明黑色素瘤去分化响应促炎细胞因子的表观遗传机制

• 批准号: 10221649
• 负责人: Yeon Joo Kim
• 金额: $ 4.67万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2022-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10221649
• 关键词: ATAC-seq; Adoptive Cell Transfers; Antigens; Automobile Driving; Binding; Bioinformatics; Biopsy; CRISPR/Cas technology; Cell Cycle Arrest; Cell Line; Cells; Chromatin; Clinical; Clinical Data; Coculture Techniques; Data; Development; Down-Regulation; Embryonic Development; Epigenetic Process; Exhibits; Exposure to; Flow Cytometry; Gene Expression; Gene Expression Profile; Genes; Genome; Growth; Hematopoietic; Human; Immune; Immune response; Immunotherapy; In Vitro; Inflammation; Inflammatory; Interferon Type II; Knock-out; Knowledge; Light; Link; Malignant Neoplasms; Measures; Mediating; Melanoma Cell; Metastatic Melanoma; Methods; Molecular; Mus; NGFR Protein; NGFR gene; Neural Crest; Neural Crest Cell; Normal Cell; Patients; Phenotype; Pigments; Relapse; Reporting; Repression; Resistance; Resistance development; Role; Skin; Skin Cancer; T-Cell Receptor; T-Lymphocyte; TNF gene; Testing; Therapeutic; Time; Transgenic Organisms; Tumor Antigens; Tumor Suppressor Proteins; Tumor-infiltrating immune cells; Up-Regulation; anti-PD1 antibodies; base; cancer cell; cancer immunotherapy; cell killing; cell motility; cell type; chromatin remodeling; cytokine; engineered T cells; epigenome; epithelial to mesenchymal transition; experimental study; genetic signature; human data; imaging system; improved; in vitro Model; in vivo; interest; live cell imaging; macrophage; melanocyte; melanoma; microphthalmia-associated transcription factor; mouse model; neoplastic cell; pembrolizumab; programs; response; success; survival outcome; targeted treatment; transcription factor; transcriptome sequencing; tumor

PROJECT SUMMARY/ ABSTRACT The advent of cancer immunotherapy has remarkably altered the treatment landscape for patients with advanced melanoma, a highly aggressive skin cancer with traditionally dismal survival outcomes. Despite notable success of immunotherapy and many studies aimed at improving these therapeutic strategies, a large proportion of patients fail to respond or develop resistance that leads to relapse. One of the ways melanoma can adapt to immune attack is through the phenomenon of dedifferentiation, whereby the tumor cell loses melanoma-specific antigens and upregulates neural crest markers. This altered phenotype has been studied in mouse models of immunotherapy and in vitro models of targeted therapy, and it has also been linked to invasiveness and epithelial-to-mesenchymal transition. Notably, we have identified cases of dedifferentiation in our clinical data from the biopsies of patients who failed to respond to immunotherapy. However, the molecular mechanism underlying the dedifferentiation provoked by tumor necrosis factor alpha (TNFa) or long-term interferon gamma (IFNg), two major T cell cytokines, has not been thoroughly explored despite the current gap in our knowledge. We hypothesize that IFNg and TNFa drive alteration of the global chromatin landscape to induce differentiation programs that shift the melanoma cell identity, and that the transcription factor IRF8 is the driver of this observed phenotypic plasticity. We propose to study these hypotheses by recapitulating dedifferentiation in human melanoma cell lines in vitro. To determine the direction of shift in cell state, we will investigate the changes in the epigenetic landscape using ATAC-seq. We will also perform RNA- seq and employ various bioinformatic analysis methods to identify the melanoma-specific immune-driven gene signature. Furthermore, based on our preliminary data, we propose to test IRF8's role in driving dedifferentiation by using the CRISPR/Cas9 technology. Finally, we will elucidate whether the altered melanoma state confers resistance to further T cell attack by performing co-culture experiments with live cell imaging. These studies will improve our understanding of the mechanism of immune-driven phenotypic alteration in melanoma and suggest potential ways to circumvent this mode of resistance to immunotherapy.

项目总结/摘要 癌症免疫疗法的出现显著改变了癌症患者的治疗前景， 晚期黑色素瘤，一种高度侵袭性的皮肤癌，传统上生存率很低。尽管 免疫疗法的显著成功和许多旨在改善这些治疗策略的研究， 部分患者没有反应或产生耐药性，导致复发。黑色素瘤 可以适应免疫攻击是通过去分化现象，从而使肿瘤细胞失去 黑色素瘤特异性抗原和上调神经嵴标志物。这种改变的表型已经在 免疫治疗的小鼠模型和靶向治疗的体外模型，它也与 侵袭性和上皮向间充质转化。值得注意的是，我们已经确定了去分化的情况下， 我们的临床数据来自对免疫治疗无效的患者的活检。然而，分子 肿瘤坏死因子α（TNF α）或长期诱导的去分化的潜在机制 干扰素γ（IFNg），两种主要的T细胞细胞因子，尽管目前的差距，尚未得到彻底的探讨 在我们的知识。我们假设IFNg和TNFa驱动全局染色质景观的改变， 诱导分化程序，改变黑色素瘤细胞的身份， 因子IRF 8是这种观察到的表型可塑性的驱动因素。我们建议研究这些假设， 在体外重演人黑素瘤细胞系的去分化。确定单元格中移动方向的步骤 状态，我们将使用ATAC-seq调查表观遗传景观的变化。我们还将进行RNA- seq和使用各种生物信息学分析方法来鉴定黑色素瘤特异性免疫驱动基因 签名.此外，根据我们的初步数据，我们建议测试IRF 8的作用，在驾驶 通过使用CRISPR/Cas9技术进行去分化。最后，我们将阐明， 黑色素瘤状态通过与活细胞进行共培养实验赋予对进一步T细胞攻击的抗性 显像这些研究将提高我们对免疫驱动的表型免疫应答机制的理解。 改变黑色素瘤，并提出潜在的方法来规避这种模式的免疫治疗的阻力。