Targeting Glycolytic Control of Melanoma Cell Survival

描述(由申请人提供)：生存信号改变是恶性黑色素瘤细胞对药物诱导的细胞凋亡产生抵抗的标志。以往的研究表明，癌细胞的存活依赖于甲基乙二醛(MG)对细胞死亡途径的调节，MG是糖酵解的反应性副产物，通过翻译后修饰和参与细胞生存的靶蛋白的功能改变来发挥作用。我们的初步数据表明，热休克蛋白27(Hsp27)是人黑色素瘤MG-加合物的唯一靶点，MG-拮抗剂选择性地诱导人黑色素瘤细胞的凋亡和化疗增敏。在这项提议中，我们将检验这样一种假设，即黑色素瘤细胞存活的糖酵解控制是由MG加合物热休克蛋白27(MG-Hsp27)介导的，MG-Hsp27是一种新的治疗靶点，可通过特定的MG拮抗剂进行小分子调节。首先，MG-Hsp27将通过绘制人黑色素瘤MG-Hsp27蛋白质组在分子、细胞和组织水平上进行表征(特定目标#1)。人黑色素瘤HSP27的确切结构和位点(S)将在黑色素瘤细胞系和组织中通过磷酸化和MG加成的翻译后修饰来确定。然后，MG-HSP27将被确认为调节黑色素瘤细胞存活的分子靶点(特定目标2)。MG-Hsp27生存信号的分子机制将被阐明，并将通过代谢、药理和遗传调控来实现靶点验证。接下来，基于细胞的小分子MG拮抗剂的靶向调节和抗黑色素瘤活性的筛选将确定一系列具有生物活性的MG-Hsp27-抑制剂(特定目标3)。最后，MG拮抗剂的化疗潜力的原则证据将在使用MG拮抗剂作为单一药物或与其他化疗药物联合使用的异种小鼠黑色素瘤模型中进行测试(特定目标#4)。这项拟议研究的成功完成将确定癌细胞的一种独特的代谢脆弱性，这种脆弱性可以被小分子拮抗剂攻击。专业描述：黑色素瘤是一种高度侵袭性的肿瘤，起源于人类皮肤中产生色素的细胞，目前发病率不断上升，超过任何其他癌症。我最近的研究表明，糖能量代谢的副产品甲基乙二醛可能是人类黑色素瘤细胞的致命弱点。该研究旨在阐明甲基乙醛调节黑色素瘤细胞存活的分子机制，并测试甲基乙醛的拮抗剂作为新的抗黑色素瘤药物。

DESCRIPTION (provided by applicant): Altered survival signaling is a hallmark of malignant melanoma cells resulting in resistance to drug-induced apoptosis. Previous studies suggest that cancer cell survival depends on the modulation of cell death pathways by methylglyoxal (MG), a reactive by-product of glycolysis that acts by posttranslational modification and functional alteration of target proteins involved in cellular survival. Our preliminary data indicate that heat shock protein 27 (Hsp27) is the exclusive target of MG-adduction in human melanoma and that MG-antagonists selectively induce apoptosis and chemosensitization in human melanoma cells. In this proposal we will test the hypothesis that the glycolytic control of melanoma cell survival is mediated by MG adducted heat shock protein 27 (MG-Hsp27), a novel therapeutic target amenable to small molecule modulation by specific MG-antagonists. First, MG-Hsp27 will be characterized at the molecular, cellular, and tissue level by mapping the human melanoma MG-Hsp27 proteome (specific aim #1). The exact structure and site(s) of human melanoma Hsp27 posttranslational modification by phosphorylation and MG-adduction will be determined in melanoma cell lines and tissue. MG-Hsp27 will then be validated as a molecular target for the modulation of melanoma cell survival (specific aim #2). The molecular mechanism of survival signaling by MG-Hsp27 will be elucidated, and target validation will be achieved by metabolic, pharmacological, and genetic modulation of MG-Hsp27. Next, cell-based screening of small molecule MG antagonists for potency of target modulation and anti-melanoma activity will identify a lead series of bioactive MG-Hsp27-inhibitors (specific aim #3). Finally, proof-of-principle evidence for chemotherapeutic potential of MG-antagonists will be tested in a xenograft mouse melanoma model using MG-antagonists as single agents or in combination with other chemotherapeutic agents (specific aim #4). Successful completion of the proposed research will identify a unique metabolic vulnerability of cancer cells that can be attacked by small molecule antagonists. Lay description: Melanoma, a highly aggressive tumor that originates from pigment producing cells in human skin, has an increasing incidence that currently surpasses that of any other cancer. My recent research suggests that a byproduct of sugar energy metabolism called methylglyoxal may represent an Achilles heel of human melanoma cells. The proposed research aims to elucidate the molecular mechanism that regulates melanoma cell survival by methylglyoxal and to test antagonists of methylglyoxal as novel anti-melanoma therapeutics.