Identification of small molecule modulators of MITF

描述（由申请人提供）：侏儒症相关转录因子（MITF）是一种受谱系限制的黑素细胞存活和分化的重要调节因子。在15-20%的黑色素瘤中，MITF被扩增，并表现为真正的癌基因：这些黑色素瘤依赖于MITF的活性，抑制MITF的表达或活性导致细胞周期停滞、细胞凋亡和致瘤性丧失。鉴于其在黑素细胞和黑色素瘤生物学中的重要性，抑制其活性可能为黑色素瘤的治疗提供一种新的治疗方法。这项研究的长期目标是了解在黑素细胞谱系中调节MITF表达的信号通路。我们的中心假设是下调MITF可能是黑色素瘤的一种治疗策略。我们的目标是使用高通量筛选（HTS）鉴定MITF的小分子抑制因子，从而更好地了解MITF的生物学功能并开发用于黑色素瘤治疗的治疗剂。对于这项RO3拨款，我们提出了三个特定目标：(1)使用基于细胞的荧光素酶报告基因检测对MITF活性调节剂进行小分子筛选；(2)进行二级和(3)三级筛选，以验证在SPECIFIC Aim 1中鉴定的激活化合物。虽然超出了本应用的范围，但我们将尝试开发进一步改进活性化合物结构和功能的策略。在该项目结束时，我们将能够鉴定出MITF的几个高活性和特异性抑制因子，从而进一步研究MITF的生物学功能。这些化合物的鉴定也可能导致黑色素瘤的新治疗方法的发展。

DESCRIPTION (provided by applicant): Micropthalmia-associated transcription factor (MITF) is an lineage-restricted, essential regulator of melanocyte survival and differentiation. In 15-20% of melanomas, MITF is amplified and is a behaves as a bone-fide oncogene: these melanomas are addicted to MITF activity, and suppression of expression or activity leads to cell cycle arrest, apoptosis and loss of tumorigenicity. Given its importance in melanocyte and melanoma biology, suppression of its activity may offer a novel therapeutic approach for the treatment of melanoma. The long-term GOAL of this research is to understand the signaling pathways that modulate MITF expression in the melanocyte lineage. Our CENTRAL HYPOTHESIS is that down-regulation of MITF may a therapeutic strategy for melanoma. Our OBJECTIVE is to identify small molecule suppressors of MITF using high throughput screening (HTS), with which to better understand the biological functions of MITF and to develop therapeutic agents for melanoma therapy. For this RO3 grant, we propose three SPECIFIC AIMS: (1) To perform a small molecule screen for modulators of MITF activity using cell-based luciferase reporter assays and (2) To perform secondary and (3) tertiary screens to validate activate compounds identified in Specific Aim 1. Although beyond the scope of this application, we will attempt to develop strategies for further refinement of the structure and function of active compounds. At the conclusion of the proposed project, we will be able to identify several highly active and specific suppressors of MITF with which to further investigate the biological functions of MITF. The identification of these compounds may also lead to development of novel therapeutic approaches for melanoma. PUBLIC HEALTH RELEVANCE: Identifying modulators of the micropthalmia-associated transcription factor (MITF) is critical to understand this master regulator of pigmentation and frequently mutated melanoma oncogene. Because modulation of MITF can be exploited for the treatment of melanoma, we expect that our screen will be relevant to the mission of NIH and will be interesting to both clinicians as well as researchers interested in the molecular pathogenesis of melanoma.