Elucidating neural crest-like reprogramming in melanoma

阐明黑色素瘤中的神经嵴样重编程

• 批准号: 9012777
• 负责人: Mizuho Fukunaga-Kalabis
• 金额: $ 20.42万
• 依托单位: WISTAR INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-02-11 至 2017-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9012777
• 关键词: Allografting; Antibodies; Antigens; Binding; Biological; Biological Assay; CXCR; Cell Line; Cells; Cessation of life; Complementary DNA; Cytotoxic T-Lymphocytes; Data; Development; Developmental Gene; Diagnostic Neoplasm Staging; Embryo; Exhibits; Freezing; Gene Expression Profiling; Gene Targeting; Genetic; Goals; Health; Homeobox; Human; IL8 gene; Immune; Immune response; Immunologic Monitoring; Immunologic Surveillance; Immunotherapeutic agent; Immunotherapy; In Vitro; Inflammatory; Knowledge; Lentivirus Vector; Link; Liver; Malignant Neoplasms; Masks; Melanoma Cell; Metastatic Melanoma; Molecular; Morphology; Mus; Neoplasm Metastasis; Neural Crest; Normal Cell; Pathway interactions; Pharmaceutical Preparations; Phenotype; Play; RNA Interference; Regulation; Resistance; Role; STAT3 gene; Sequence Analysis; Signal Transduction; Skin; Skin Cancer; Skin Neoplasms; Staging; Stem cells; Survival Rate; System; Testing; Transcription Repressor/Corepressor; Tumor Biology; cancer cell; cell motility; cellular targeting; chromatin immunoprecipitation; design; gain of function; immunogenic; in vivo; inhibitor/antagonist; knock-down; loss of function; melanocyte; melanoma; microphthalmia-associated transcription factor; next generation sequencing; novel; novel therapeutics; outcome forecast; overexpression; precursor cell; programs; promoter; resistance mechanism; small molecule; stem; therapy resistant; transcription factor; tumor; tumor immunology; whole genome

DESCRIPTION (provided by applicant): Melanoma is the most deadly type of skin cancer with a five-year survival rate for late stage cancer of only 15%. Key reasons for the poor prognosis of this tumor type are its high rate of metastasis and resistance to therapy. To date, very little is known about the molecular pathways governing the acquisition of the metastatic phenotype and therapy resistance in melanoma. Emerging evidence suggests that cancer cells use developmental programs for tumor dissemination, propagation, and resistance to currently available therapies. Our overall hypothesis is that melanoma cells hijack the neural crest developmental program for their progression. We recently discovered that neural crest-like reprogramming is achieved in melanocytes when Msh homeobox 1 (MSX1) is overexpressed. MSX1-expressing melanocytes exhibit a similar morphology and phenotype to neural crest-like precursor cells in human skin. In the embryo, MSX1 is a transcriptional repressor essential for neural crest development. Our data demonstrate that MSX1 binds and suppresses the proximal promoter of microphthalmia-associated transcription factor (MITF), the master transcriptional regulator of melanocyte differentiation. Expression of MSX1 correlates with melanoma progression, and our data show that knockdown of MSX1 in metastatic cells significantly impairs motility in vitro and reduces liver colonization in vivo. MSX1 expression is upregulated by inflammatory factors in the microenvironment, which has been shown to play a role in cellular plasticity and immunotherapy resistance in melanoma. In this proposal, using our knowledge of tumor biology and tumor immunology, we propose to study a novel link between the embryonic phenotype of cancer and immune response to cancer cells. Our goal is to delineate the mechanisms for how MSX1 dictates a neural crest-like plastic phenotype in melanoma cells, which helps them escape immune surveillance, and ultimately promotes their metastasis. In Specific Aim 1, we will define the role of neural crest-like reprogramming in resistance to immunotherapy. We will take gain-of-function (cDNA over-expression) and loss-of-function (RNAi) approaches using lentiviral vectors to assess the biological significance of MSX1-induced neural crest-like dedifferentiation in human melanoma cells using the cytotoxic T lymphocyte assay and an immune competent, syngeneic, allograft mouse melanoma system. We expect that by targeting neural crest-like reprogramming, this will freeze the phenotype of melanoma cells in more differentiated and more immunogenic state, thereby sensitizing melanoma cells to currently available immunotherapies. The design of small molecules inhibiting transcription factors is a challenge; therefore we will explore upstream inducers and downstream targets of MSX1 to identify melanoma-specific druggable targets for MSX1-driven dedifferentiation in Specific Aim 2. Successful completion of this study will identify melanoma-specific dedifferentiation mechanisms and provide a proof-of-principle to target cellular plasticit in melanoma, especially in combination with immunotherapy.

描述（由申请人提供）：黑色素瘤是最致命的皮肤癌类型，后期癌症的生存率仅为15％。这种肿瘤类型预后不良的关键原因是其转移率很高和对治疗的耐药性。迄今为止，关于掌握转移性表型和黑色素瘤耐药性的分子途径知之甚少。新兴的证据表明，癌细胞使用发育计划进行肿瘤传播，繁殖和对当前可用疗法的抵抗力。我们的总体假设是，黑色素瘤细胞劫持了神经rest发育计划的进展。我们最近发现，当MSH Homeobox 1（MSX1）过表达时，在黑素细胞中实现了类似神经粉的重编程。表达MSX1的黑素细胞表现出与人皮肤中神经rest的前体细胞相似的形态和表型。在胚胎中，MSX1是神经rest发育必不可少的转录阻遏物。我们的数据表明，MSX1结合并抑制了与黑素细胞分化的主转录调节剂（MITF）的近端启动子（MITF）。 MSX1的表达与黑色素瘤的进展相关，我们的数据表明，转移细胞中MSX1的敲低显着损害了体外运动，并减少了体内肝脏定殖。 MSX1表达在微环境中被炎症因子上调，已显示出在黑色素瘤中的细胞可塑性和免疫疗法抗性中起作用。在此建议中，使用我们对肿瘤生物学和肿瘤免疫学的了解，我们建议研究癌症的胚胎表型与对癌细胞的免疫反应之间的新联系。我们的目标是描述MSX1如何决定黑色素瘤细胞中神经粉状的塑性表型的机制，这有助于它们逃脱免疫监测，并最终促进其转移。在特定目标1中，我们将定义神经克雷斯特样重编程在抵抗免疫疗法中的作用。我们将使用慢病毒载体采取功能获得（cDNA过表达）和功能丧失（RNAI）方法，以评估MSX1诱导的人类黑色素瘤细胞中的神经克雷斯特的生物学意义。我们预计，通过靶向神经波峰的重编程，这将冻结在更分化和更加免疫原性状态下黑色素瘤细胞的表型，从而使黑色素瘤细胞对当前可用的免疫疗法敏感。抑制转录因子的小分子的设计是一个挑战。因此，我们将探索MSX1的上游诱导剂和下游靶标，以确定针对特定目标2的黑色素瘤特异性可毒靶标的。