Role of Notch Signaling in Melanoma Transdifferentiation and Tumor Progression

Notch 信号传导在黑色素瘤转分化和肿瘤进展中的作用

• 批准号: 9275430
• 负责人: Vijayasaradhi Setaluri
• 金额: --
• 依托单位: WM S. MIDDLETON MEMORIAL VETERANS HOSP
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-10-01 至 2018-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9275430
• 关键词: Advanced Malignant Neoplasm; Agreement; Attenuated; BRAF gene; Benign; Binding; Biology; Cell Cycle Arrest; Cell Line; Cells; Clinical; Combination Drug Therapy; Cutaneous Melanoma; Data; Defect; Development; Developmental Process; Diagnosis; Differentiation Antigens; Disease; Disease-Free Survival; Down-Regulation; ES01; Early Diagnosis; Event; Exhibits; Exposure to; Genes; Genetic; Genetic Crosses; Genetic Models; Growth; Immunocompromised Host; In Vitro; Laboratories; Lead; Malignant - descriptor; Malignant Neoplasms; Melanins; Melanocytic nevus; Melanoma Cell; Metastatic Melanoma; Metastatic to; Methods; Methylation; Microtubule Stabilization; Microtubule-Associated Protein 2; Microtubules; Military Personnel; Mitotic; Mitotic spindle; Molecular; Mus; Neoplasm Metastasis; Neural Crest; Neuronal Differentiation; Neurons; Oncogenic; PTEN gene; Patients; Pigments; Play; Premalignant; Prevention; Primary Lesion; Prognostic Marker; Proteins; Publishing; Recording of previous events; Recurrence; Regulation; Research; Resistance; Resistance development; Risk; Role; Sea; Signal Pathway; Signal Transduction; Skin; Skin Cancer; Skin Neoplasms; Specimen; Survival Analysis; Tamoxifen; Testing; The Sun; Tissue Microarray; Transcription Repressor/Corepressor; Transgenic Mice; Ultraviolet Rays; United States; Up-Regulation; Veterans; advanced disease; attenuation; base; brain cell; cancer diagnosis; conventional therapy; demethylation; effective therapy; in vivo; inducible gene expression; inhibitor/antagonist; innovation; knock-down; melanocyte; melanoma; neoplastic; neoplastic cell; neurogenesis; notch protein; prevent; prognostic significance; promoter; public health relevance; relating to nervous system; targeted treatment; therapeutic target; therapy development; transdifferentiation; tumor; tumor growth; tumor progression; tumorigenesis

DESCRIPTION (provided by applicant): Cutaneous melanoma, the deadliest form of skin cancer, arises from neural crest derived melanocytes. Much progress has been made in delineating molecular events that initiate the cascade of malignant changes leading to metastatic melanoma. These advances have led to some remarkable improvements in treatment of melanoma. However, the notorious intrinsic resistance to conventional therapies and development of treatment resistance to targeted therapies continue to be vexing problems highlighting the need to explore additional avenues for preventing melanoma development and progression. In this context, the role for Notch signaling in melanoma remains to be fully understood and exploited. Notch signaling, an important cell signaling mechanism, is known to play a role in melanocyte development. However, molecular mechanisms and the specific roles Notch plays in melanoma development and progression are not completely understood. Preliminary data obtained in my laboratory showed a possible biphasic role for Notch signaling in melanoma tumor progression. In skin resident benign neo-plastic melanocytes and early primary melanoma, a downregulation of Notch signaling and its effector HES1, a transcriptional repressor, allows elaboration of neuronal differentiation. This is indicated by the expression of a protein, MAP2 that is normally present only in terminally differentiated neurons that lack ability to divide. A retrospective survival analysis showed that patients whose primary skin tumors were MAP2-positive survived significantly longer without melanoma recurrence than those diagnosed with MAP2-negative melanoma. MAP2 is absent or found less frequently in metastatic melanoma. In agreement with its primary function of binding to and stabilizing microtubules, MAP2 alters the dynamic instability of microtubules and induces mitotic spindle defects in melanoma. Preliminary data also showed that molecular players that initiate the malignant changes in melanocytes also play a role in activation of this neuronal differentiation marker. Thus, activation of a neuron-specific gene in melanocytes at early stages of malignant transformation correlates with inhibition of proliferation in vitro and tumor growth and progression in vivo. Based on these data, we hypothesized that Notch signaling, has a dual or biphasic role in melanoma. First, Notch signaling is downregulated during early steps in malignant transformation by sustained oncogenic signaling to promote neuronal differentiation as a fail-safe mechanism against melanoma tumorigenesis, and additional genetic events such as loss of PTEN then lead to upregulation of Notch signaling to support melanoma tumor progression. To test this hypothesis, we will use a combination of in vitro and in vivo approaches to accomplish the following Aims: In Aim 1, we will study mechanisms of transdifferentiation in melanocytes and patient-derived melanoma using primary melanocytes and a panel of well-characterized melanoma cell lines, we will investigate the molecular mechanisms. In Aim 2, we will investigate the role of Notch signaling and neuronal differentiation in melanomagenesis using metastatic melanoma cells with stable knockdown of HES1and/or treated with inhibitors of Notch signaling in immunocompromised mice, and a genetic cross between transgenic mice with inducible MPA2 expression in melanocytes and BrafCa/Pten-/- mice. In Aim 3, we will evaluate the prognostic significance of Notch in melanoma employing quantitative immunohistochemical method to analyze an in- house created melanoma tissue microarray consisting of 225 stage I-III primary melanoma specimens with complete clinical history. The hypothesis on the dual role of Notch in transdifferentiation and use of combination of mouse genetic model and a fully annotated melanoma tissue microarray are the innovative aspects of the proposed research. Data obtained from these studies have the potential to uncover more reliable prognostic markers for melanoma aggressiveness and impact the management of aggressive cutaneous melanoma.

描述（由申请人提供）： 皮肤黑色素瘤是皮肤癌最致命的形式，是由神经rest衍生的黑素细胞引起的。在描述分子事件中取得了很多进展，这些事件引发了导致转移性黑色素瘤的恶性变化的级联变化。这些进步导致了黑色素瘤治疗的一些显着改善。但是，臭名昭著的对常规疗法的内在抗药性和对靶向疗法的治疗耐药性的发展继续是令人沮丧的问题，突显了探索防止黑色素瘤发育和进展的其他途径的需求。在这种情况下，Notch信号在黑色素瘤中的作用仍有待完全理解和利用。 Notch信号传导是一种重要的细胞信号传导机制，已知在黑素细胞发育中起作用。然而，分子机制和特定作用在黑色素瘤发育和进展中尚未完全了解。 在我的实验室获得的初步数据显示，在黑色素瘤肿瘤进展中缺口信号传导可能具有双相作用。在皮肤常备的良性新塑性黑色素细胞和早期原发性黑色素瘤中，Notch信号传导及其效应器HES1的下调是转录阻遏物，允许阐述神经元分化。这是 用蛋白质的表达表示，MAP2通常仅存在于缺乏分裂能力的终末分化神经元中。回顾性生存分析表明，与患有MAP2阴性黑色素瘤诊断的患者相比，原发性皮肤肿瘤的MAP2阳性生存时间明显更长，没有黑色素瘤复发。在转移性黑色素瘤中，MAP2不存在或较少发现。与其与微管结合和稳定的主要功能一致，MAP2改变了微管的动态不稳定性，并诱导黑色素瘤中有丝分裂纺锤体缺陷。初步数据还表明，启动黑素细胞变性变化的分子参与者在激活该神经元分化标记中也起作用。因此，在恶性转化的早期黑素细胞中神经元特异性基因的激活与体外的抑制和体内肿瘤生长和进展有关。基于这些数据，我们假设Notch信号在黑色素瘤中具有双重或双相作用。首先，通过持续的致癌信号传导传导在恶性转化的早期转化期间，Notch信号被下调，以促进神经元分化，作为针对黑色素瘤肿瘤发生的故障安全机制，以及其他遗传事件，例如PTEN的丧失，然后导致Notch信号的上调以支持黑色素瘤肿瘤的进展。为了检验这一假设，我们将使用体外和体内方法的组合来实现以下目的：在AIM 1中，我们将研究黑色素细胞和患者衍生的黑色素瘤的转化机制，使用原发性黑素细胞和良好的黑色素瘤细胞系小组，我们将研究细胞的机制。在AIM 2中，我们将研究Notch信号传导和神经元分化在黑色素作用中的作用，使用转移性黑色素瘤细胞具有稳定的HES1and/或用Notch信号传导抑制剂治疗的免疫功能低下小鼠中的抑制剂，以及在糖尿病和Braffca/Braffca/Braffca中的转基因小鼠之间的遗传小鼠之间的遗传交叉中的作用。在AIM 3中，我们将采用定量免疫组织化学方法来评估Notch在黑色素瘤中的预后意义，以分析由225期I-III阶段的原发性黑色素瘤标本组成的内部内部黑色素瘤组织微阵列，具有完整的临床史。 Notch在跨分化和使用小鼠遗传模型和完全注释的黑色素瘤组织微阵列中的双重作用的假设是拟议研究的创新方面。从这些研究中获得的数据有可能发现更可靠的预后标记，以实现黑色素瘤的侵略性并影响侵袭性皮肤黑色素瘤的管理。