Targeting prostaglandin biosynthesis and action in lymphangioleiomyomatosis

摘要 淋巴管肌瘤病(LAM)是一种毁灭性的肺部疾病，几乎只影响年轻人 女人。LAM以平滑肌细胞浸润和肺气肿样肺破坏为特征。林是 与TSC2突变导致雷帕霉素复合体1的哺乳动物靶标激活有关 (MTORC1)。尽管mTORC1抑制剂雷帕霉素稳定肺功能并改善LAM的症状 患者，停药后肺功能下降，药物的长期安全性和有效性是 未知。因此，人们迫切需要更有效的治疗方法，但尚未得到满足。尽管在以下方面取得了许多进展 了解mTOR依赖通路在LAM进展中的作用，LAM主要 对女性的影响还不是很清楚。在迈尔斯试验中，肺功能下降的速度是 绝经前患者多于绝经后患者，提示雌激素在肺组织中起主要作用 功能衰退。我们的中心假设是雌激素促进前列腺素的生物合成和作用 TSC2缺陷细胞中的程序，导致肿瘤生长和肺气肿样破坏和肺 功能衰退。在目标1中，我们将检验雌激素和TSC2丢失协同作用于 调节控制COX-2表达和前列腺素生物合成的转录机制。我们进一步 假设雌激素和TSC2缺乏症增强的前列腺素代谢产物调节细胞的功能 LAM患者来源的细胞和呼吸道结构细胞。在目标2中，我们将检验雌激素和 TSC2缺乏协同促进前列腺素的产生，从而促进破坏性肺 重塑和肺功能下降。我们推测联合抑制前列腺素 COX1/2抑制剂的生物合成和西罗莫司阻断mTORC1将诱导雌激素的消退。 促进LAM模型小鼠已建立的肺损伤，改善肺生理功能。在目标3中，我们 将检验这样一种假设，即COX1/2抑制剂和COX1/2抑制剂联合抑制前列腺素合成 西罗莫司阻断mTORC1的耐受性良好，比单用西罗莫司更有效。我们进一步 提出以血液为基础的前列腺素代谢产物是疾病严重程度和疗效的生物标志物 在LAM的回应。在整个提案中，我们将使用创新的尖端技术，包括 CHIP-SEQ识别雌激素调节的转录因子激活，体内模型的无创成像 为了寻找肺癌和COX-2活性的证据，以及实时三维计算机的应用- 断层扫描结合肺生理学在小鼠模型中的应用。这个项目的意义在于它将揭示 第一次，雌激素如何在破坏性的肺重塑和肺功能衰退中起作用。 这项研究将产生很大的影响，因为LAM在完好无损的女性中进展更快 雌激素轴，并导致呼吸衰竭和死亡。尽管在理解mTOR方面取得了许多进展- 尽管治疗依赖于多种途径，但仍迫切需要为LAM女性患者提供更有效的治疗选择。

Abstract Lymphangioleiomyomatosis (LAM) is a devastating pulmonary disease almost exclusively affecting young women. LAM is characterized by smooth muscle cell infiltration and emphysema-like lung destruction. LAM is associated with mutations in the TSC2 resulting in activation of the mammalian target of rapamycin complex 1 (mTORC1). Although the mTORC1 inhibitor rapamycin stabilizes lung function and improves symptoms in LAM patients, lung function declines after drug discontinuation and the long-term safety and efficacy of the drug are unknown. There is therefore an urgent, unmet need for more effective therapies. Despite many advances in understanding the role of mTOR-dependent pathways in LAM progression, the reason that LAM primarily affects women are not understood. In the MILES trial, lung function declined 5 times more rapidly in premenopausal patients than post menopausal patients, suggesting that estrogen plays a major role in lung function decline. Our central hypothesis is that estrogen promotes prostaglandin biosynthesis and action programs in TSC2-deficient cells, leading to tumor growth and emphysema-like destruction and pulmonary function decline. In Aim 1, we will test the hypothesis that estrogen and TSC2 loss act synergistically to regulate transcription machinery that controls COX-2 expression and prostaglandin biosynthesis. We further postulate that prostaglandin metabolites enhanced by estrogen and TSC2-deficiency modulate the function of LAM patient-derived cells and airway structural cells. In Aim 2, we will test the hypothesis that estrogen and TSC2 deficiency synergistically enhance prostaglandin production, thereby promoting destructive lung remodeling and pulmonary function decline. We postulate that that the combined suppression of prostaglandin biosynthesis by a COX1/2 inhibitor and mTORC1 blockade with sirolimus will induce regression of estrogen- promoted established lung lesion and improve pulmonary physiology in mouse models of LAM. In Aim 3, we will test the hypothesis that the combined suppression of prostaglandin biosynthesis by a COX1/2 inhibitor and mTORC1 blockade with sirolimus will be well-tolerated and more effective than sirolimus alone. We further propose that blood-based prostaglandin metabolites are biomarkers for disease severity and therapeutic responses in LAM. Throughout the proposal, we will utilize innovative, state-of-the-art technology including ChIP-Seq to identify estrogen-regulated transcription factor activation, non-invasive imaging of in vivo models for evidence of lung tumor and COX-2 activities, and application of real-time three-dimensional computer- tomography coupled with lung physiology in mouse models. The significance of this project is that it will reveal for the first time how estrogen contributes to the destructive lung remodeling and pulmonary functional decline. This study will have high impact because LAM leads progresses much more rapidly in women with an intact estrogen axis and results in respiratory failure and death. Despite many advances in understanding mTOR- dependent pathways, there remains a critical need for more effective therapeutic options for women with LAM.