Molecular Determinants of Brain metastatic Melanoma

描述：（改编自研究者摘要） 恶性黑色素瘤进展为高侵袭性脑转移 疾病仍然在很大程度上未知。我们以前已经证明，某些 神经营养因子（NT）及其受体p75 TR调节黑色素瘤的侵袭 以及一种叫做乙酰肝素酶的酶的活性。这 酶是一个关键的决定因素，为成功降解的 肿瘤周围细胞外基质（ECM）：乙酰肝素酶降解乙酰肝素 硫酸蛋白聚糖（HSPG），这是重要的ECM成分，在网站 在HS线性链中。我们的假设是NT/p75 NTR在细胞凋亡中起重要作用， 在黑色素瘤脑侵袭中，NT调节的乙酰肝素酶在其中至关重要 转移性黑素瘤进展是抗转移的潜在靶点 毒品本申请的目的是确定p75 NTR功能作为一种免疫调节剂。 脑转移瘤形成的分子决定因素及乙酰肝素酶的作用 在侵袭和血管生成方面。我们选择具有低/高p75 NTR的黑素瘤细胞， 表达并产生抗人乙酰肝素酶的单克隆抗体， 抑制其酶活性和实验性转移形成。在 此外，我们还获得了最近克隆的人乙酰肝素酶， 探针和新的重要酶抑制剂。我们的具体目标是： 1. p75 NTR作为脑转移性黑色素瘤的分子决定因子 细胞，这将通过修饰p75 NTR基因表达来实现， 分析p75 NTR变体在裸鼠中的器官定殖能力， 特别是大脑。 2.为了表征NT调节的乙酰肝素酶基因表达的特定步骤， 转移的恶性黑色素瘤，这将是通过研究 人乙酰肝素酶的分布和机制，以测试 乙酰肝素酶在黑色素瘤转移的多步骤过程中的作用 3.确定乙酰肝素酶在血管生成中的作用， 通过将血管生成分子和模型与乙酰肝素酶相关联来完成 通过使用纯化的酶和HS底物亚群 对应的HSPG。 我们预计，我们提出的研究结果将从根本上 推进脑肿瘤生物学和转移性ECM处理领域。的 重要的是，它们有望为预防和 治疗干预，这将是特别重要的增长， 患有恶性黑色素瘤的人数， 黑色素瘤问题的“紧迫性”。

DESCRIPTION: (Adapted from the investigator's abstract) Mechanisms responsible for malignant melanoma progression to highly aggressive brain-metastatic disease remain largely unknown. We have previously demonstrated that certain neurotrophins (NT) and their receptor p75 TR modulate the invasion of melanoma cells to the brain and the activity of an enzyme, called heparanase. This enzyme is a key determinant for the successful degradation of the tumor-surrounding extracellular matrix (ECM): heparanase degrades heparan sulfate proteoglycans (HSPGs), which are important ECM components, at sites within HS linear chains. Our hypothesis is that NT/p75NTR play important roles in melanoma brain invasion and that NT-regulated heparanase is critical in the metastatic melanoma progression being a potential target for antimetastasis drugs. The objective of this application is to determine p75NTR function as a molecular determinant of brain metastases formation and the role of heparanase in invasion and angiogenesis. We selected melanoma cells with low/high p75NTR expression and generated a monoclonal antibody against human heparanase that inhibits its enzymatic activity and experimental metastases formation. In addition, we have access to the recently cloned human heparanase, related probes, and novel important enzyme inhibitors. Our specific aims are: 1. To define p75NTR as a molecular determinant of brain-metastatic melanoma cells, which will be accomplished by modifying p75NTR gene expression and analysis of p75NTR variants for their organ colonizing abilities in nude mice, in particular to the brain. 2. To characterize NT-regulated heparanase gene expression at specific steps of metastasis in malignant melanoma, which will be accomplished by studying the distribution and mechanisms of human heparanase to test the precise function of heparanase in the multistep process of melanoma metastasis. 3. To determine the role of heparanase in angiogenesis, which will be accomplished by relating angiogenic molecules and models to heparanase functionality by using purified enzyme and HS substrates subpopulations from corresponding HSPGs. We anticipate that the results of our proposed research will fundamentally advance the field of brain tumors biology and metastatic ECM processing. Of significance, they are expected to provide new targets for preventive and therapeutic interventions that will be particularly important to the growing numbers of persons who have malignant melanoma, and are experiencing the "urgency" of the melanoma problem.