Unraveling the molecular control of a pro-metastatic regulatory network in melanoma

 描述（由申请人提供）：拟议的跨学科研究计划结合了分子、生物化学、遗传学、人类病理学和动物功能研究，以表征促转移调控网络，该网络已被发现可通过代表不同突变亚型的广泛黑色素瘤调节转移进展。我们已发表的工作已经揭示，在大多数人黑素瘤中，三种促转移微小RNA（miR-1908、miR-199 a5 p和miR-199 a3 p）的过表达通过直接靶向ApoE基因和热休克因子DNAJA 4驱动转移定植（Pencheva et al.，Cell，2012; Pencheva，Buss等人，Cell，2014）。发现ApoE和DNAJA 4强烈抑制转移性定殖和血管生成。我们广泛的先前发表和未发表的工作支持这些基因及其网络在人类转移进展中的强大和临床病理学验证的作用。自我们最初的出版物以来，独立研究者通过证明ApoE基因抑制乳腺癌转移以及人类ApoE 4多态性增加男性和女性恶性肿瘤死亡的可能性，进一步支持了ApoE在癌症进展中的作用。这些发现作为一个整体确立了ApoE作为转移进展和肿瘤血管生成的有效和双重调节剂。因此，需要加强对调节癌症中ApoE的上游机制、其对肿瘤血管生成的下游作用机制、其治疗潜力以及ApoE多态性变体对癌症的影响的理解。目前的提议旨在回答对癌症和转移生物学具有重要意义的四个主要问题：（i）DNAJA 4热休克因子上游调节ApoE的机制是什么？(ii)ApoE与内皮LRP 8受体的结合如何抑制血管生成？(iii)我们能否开发一种由ApoE基因失活驱动的黑色素瘤转移进展的遗传模型，并使用该模型来测试ApoE肽模拟物的抗转移功效？和（iv）普遍的人ApoE 4多态性是否驱动小鼠黑素瘤转移进展。ApoE失活驱动的遗传启动的黑色素瘤转移进展模型的开发是创新的，可以有益地影响科学，医学和制药界，使我们能够在免疫模型中测试和开发ApoE肽治疗。发现调节ApoE（与痴呆和心血管疾病有关的基因）的未探索的转录后机制也可能具有广泛的科学和临床影响，并揭示ApoE治疗活化的另一种途径。测试ApoE-LRP 8对乳腺癌和肺癌的血管生成抑制的影响也可以扩大ApoE治疗对这些流行癌症的范围和影响。

 DESCRIPTION (provided by applicant): The proposed inter-disciplinary research plan combines molecular, biochemical, genetic, human pathologic, and animal functional studies to characterize a pro-metastatic regulatory network that has been found to regulate metastatic progression by a broad range of melanomas representing diverse mutational subtypes. Our published work has revealed that in the majority of human melanomas, over-expression of three pro-metastatic microRNAs (miR-1908, miR-199a5p, and miR-199a3p) drives metastatic colonization through direct targeting of ApoE gene and the heat-shock factor DNAJA4 (Pencheva et al., Cell, 2012; Pencheva, Buss et al., Cell, 2014). ApoE and DNAJA4 were found to robustly suppress metastatic colonization and angiogenesis. Our extensive previously published and unpublished work supports a robust and clinico-pathologically validated role for these genes and their network in human metastatic progression. Since our original publications, independent investigators have provided further support of a role for ApoE in cancer progression by demonstrating that the ApoE gene suppresses breast cancer metastasis and that the human ApoE4 polymorphism increases the likelihood of death from malignancy in men and women. These findings as a whole establish ApoE as a potent and dual regulator of metastatic progression and tumor angiogenesis. Thus, an enhanced understanding of the upstream mechanisms that regulate ApoE in cancer, its downstream mechanism(s) of action on tumor angiogenesis, its therapeutic potential, and the impact of ApoE polymorphic variants on cancer is required. The current proposal aims to answer four major questions of great significance to cancer and metastasis biology: (i) what is the mechanism of upstream regulation of ApoE by the DNAJA4 heat-shock factor? (ii) How does the binding of ApoE to the endothelial LRP8 receptor suppress angiogenesis? (iii) Could we develop a genetic model of melanoma metastatic progression driven by genetic inactivation of ApoE and use this model to test the anti-metastatic efficacy of an ApoE peptide mimetic? and (iv) does the prevalent human ApoE4 polymorphism drive mouse melanoma metastatic progression. The development of an ApoE inactivation driven genetically initiated model of melanoma metastatic progression is innovative and could beneficially impact the scientific, medical, and pharmaceutical communities-allowing us to test and develop ApoE peptide therapy in an immunoproficient model. Discovery of an unexplored post- transcriptional mechanism that regulates ApoE, a gene implicated in dementia and cardiovascular disease could also have broad scientific and clinical impact and reveal another avenue for therapeutic activation of ApoE. Testing the impact of angiogenic suppression of breast and lung cancer by ApoE- LRP8 could broaden the scope and impact of ApoE therapy to these prevalent cancers as well.