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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

基本信息

批准号：
9794743
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
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-10-01 至 2019-09-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9794743
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 MEKs 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 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 UV Radiation Exposure 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 therapy resistant transdifferentiation tumor tumor growth tumor progression tumorigenesis

项目摘要

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中最致命的一种，它起源于神经嵴来源的黑素细胞。已经取得了很大的进展，在描绘分子事件，启动级联恶性变化，导致转移性黑色素瘤。这些进展导致了黑色素瘤治疗的一些显著改善。然而，对常规疗法的臭名昭著的内在抗性和对靶向疗法的治疗抗性的发展仍然是令人烦恼的问题，突出了探索用于预防黑素瘤发展和进展的额外途径的需要。在这种情况下，Notch信号在黑色素瘤中的作用仍有待充分理解和利用。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，Notch在黑色素瘤发生和进展中的分子机制和具体作用尚未完全了解。在我的实验室获得的初步数据显示，在黑色素瘤肿瘤进展的Notch信号可能的双相作用。在皮肤驻留良性肿瘤黑色素细胞和早期原发性黑色素瘤中，Notch信号转导及其效应子HES 1（一种转录阻遏物）的下调允许神经元分化的精细化。这是由蛋白质MAP 2的表达指示，MAP 2通常仅存在于缺乏分裂能力的终末分化神经元中。一项回顾性生存分析显示，与确诊为MAP 2阴性黑色素瘤的患者相比，原发性皮肤肿瘤为MAP 2阳性的患者在无黑色素瘤复发的情况下生存时间明显更长。MAP 2在转移性黑色素瘤中不存在或较少发现。与其结合和稳定微管的主要功能一致，MAP 2改变了微管的动态不稳定性并诱导黑色素瘤中的有丝分裂纺锤体缺陷。初步数据还显示，启动黑素细胞恶性变化的分子参与者也在激活这种神经元分化标记物中发挥作用。因此，恶性转化早期黑素细胞中神经元特异性基因的激活与体外增殖抑制以及体内肿瘤生长和进展相关。基于这些数据，我们假设Notch信号传导在黑色素瘤中具有双重或双相作用。首先，Notch信号传导在恶性转化的早期步骤期间通过持续的致癌信号传导下调，以促进神经元分化作为针对黑素瘤肿瘤发生的故障安全机制，并且另外的遗传事件例如PTEN的丢失然后导致Notch信号传导上调以支持黑素瘤肿瘤进展。为了验证这一假设，我们将使用体外和体内方法的组合来实现以下目标：在目标1中，我们将使用原代黑素细胞和一组充分表征的黑色素瘤细胞系研究黑素细胞和患者来源的黑色素瘤中的转分化机制，我们将研究分子机制。在目标2中，我们将研究Notch信号传导和神经元分化在黑色素瘤形成中的作用，使用具有稳定敲除的HES 1和/或用Notch信号传导抑制剂处理的免疫受损小鼠中的转移性黑色素瘤细胞，以及在黑色素细胞中具有诱导型MPA 2表达的转基因小鼠和BrafCa/Pten-/-小鼠之间的遗传杂交。在目标3中，我们将采用定量免疫组织化学方法来分析内部创建的黑素瘤组织微阵列，以评估Notch在黑素瘤中的预后意义，所述黑素瘤组织微阵列由225个具有完整临床病史的I-III期原发性黑素瘤标本组成。关于Notch在转分化中的双重作用的假设以及小鼠遗传模型和完全注释的黑素瘤组织芯片的组合的使用是所提出的研究的创新方面。从这些研究中获得的数据有可能揭示黑色素瘤侵袭性的更可靠的预后标志物，并影响侵袭性皮肤黑色素瘤的管理。