Regulation of Mitochondrial Metabolism by Tyr-phosphorylated ATP Synthase Alpha-Subunit and its Therapeutic Implications in Prostate Cancer

项目摘要 癌细胞线粒体转换其代谢表型以满足高能量需求的挑战， 大分子合成肿瘤对致癌酪氨酸激酶信号传导的急性依赖性支持了它们的 快速增殖，然而，直接相关的激酶活性为线粒体，以支持这些高能量 过程仍然模糊。偶然地，我们发现了一种非受体酪氨酸激酶，ACK 1， 在Tyr 243和Tyr 246处磷酸化ATP合酶F1 α-亚基（ATP 5 F1 a）（成熟蛋白中的Tyr 200和203， 分别），其特异性地增加癌细胞中的ATP合酶活性。机械上，ATP 5 F1 a- 磷酸化不仅排除了其与其生理抑制剂ATP酶抑制因子1（IF 1）的结合， 还产生了从结合的非催化核苷酸延伸到表面的支撑结构， 降低了柔性，从而增加了酶的稳定性。新型ACK 1抑制剂（R）-9b 逆转了这一过程，诱导线粒体自噬并减缓肿瘤生长。同时， 随着正常前列腺进展到恶性阶段，观察到ATP 5 F1 a磷酸化。总体而言，这些 数据提供了癌细胞对Tyr-激酶放纵的“线粒体成瘾”的分子证据， 揭示了（R）-9b作为一种“mitocan”，它损害了癌细胞独特的代谢需求。 去势抵抗性前列腺癌（CRPC）仍然是一种无法治愈的恶性肿瘤，治疗选择有限， 是全世界男性死亡的重要原因（15）。疗效有限，耐药性迅速发展， Enzalutamide和阿比特龙，AR拮抗剂治疗建立了一个新的范式-实现现实的 在缓解的情况下，其他癌症特异性途径，包括代谢必须受到损害。该提案针对 对ACK 1/ATP 5 F1 a的线粒体代谢调节特性的详细表征 信号传导并检查（R）-9b克服恩杂鲁胺和阿比特龙抗性CRPC的能力。的 具体目标如下： 具体目标1。检查ATP 5 F1 a磷酸化调节其在前列腺中活性的机制 癌 具体目标2。探索ACK 1/ATP 5 F1 a信号在前列腺癌模型中的作用 具体目标3。Enzalutamide和阿比特龙中ACK 1/ATP 5 F1 a信号传导的体内表征详情- 前列腺癌小鼠模型和患者来源的异种移植物（PDX）中的耐药性

Project Abstract Cancer cell mitochondria switch their metabolic phenotypes to meet the challenges of high-energy demand and macromolecular synthesis. Acute dependence of tumors on oncogenic tyrosine kinase signaling support their rapid proliferation, however, direct relevance of the kinase activity for mitochondria to support these high-energy processes remains obscure. Serendipitously, we uncovered that a non-receptor tyrosine kinase, ACK1, phosphorylates ATP synthase F1 α-subunit (ATP5F1a) at Tyr243 and Tyr246 (Tyr200 & 203 in mature protein, respectively) that increased ATP synthase activity specifically in the cancer cells. Mechanistically, ATP5F1a- phosphorylation not only excluded its binding to its physiological inhibitor, ATPase Inhibitory Factor 1 (IF1), but also created a supporting structure that extended from the bound non-catalytic nucleotide to the surface, reducing the flexibility and thereby increasing the stability of the enzyme. A new class of ACK1 inhibitor, (R)-9b reversed this process, inducing mitophagy and mitigating tumor growth. Consistently, a marked increase in ATP5F1a-phosphorylations was observed as normal prostate progressed to the malignant stage. Overall, these data provide the molecular evidence for cancer cell `mitochondrial addiction’ to Tyr-kinase indulgence, and reveals (R)-9b as a ‘mitocan’ that compromises the unique metabolic needs of cancer cells. Castration resistant prostate cancer (CRPC) remains an incurable malignancy with limited treatment options and is a significant cause of deaths in men worldwide (15). Limited efficacy and rapid development of resistance for Enzalutamide and Abiraterone, AR antagonist treatment have established a new paradigm-to achieve realistic remission, other cancer specific pathways, including metabolic must be compromised. This proposal is directed towards detailed characterization of mitochondrial metabolism modulatory properties of ACK1/ATP5F1a signaling and examine ability of (R)-9b to overcome Enzalutamide and abiraterone-resistant CRPCs. The specific aims are as follows: Specific Aim 1. Examine the mechanism by which ATP5F1a-phosphorylation regulates its activity in prostate cancer Specific Aim 2. Explore the role of ACK1/ATP5F1a signaling in prostate cancer models Specific Aim 3. Detail in vivo characterization of ACK1/ATP5F1a signaling in enzalutamide and abiraterone- resistance in mouse models of prostate cancer and patient derived xenografts (PDXs)