Biomarker Discovery in Portopulmonary Hypertension

项目总结/摘要 门脉高压（PoPH）是一种肺动脉高压（PAH）， 仅用于基础肝病患者。PoPH的发病率和死亡率最高， PAH亚型，影响所有慢性肝病患者的10%，但驱动疾病的机制 发病机制知之甚少。肝门静脉高压和肝细胞功能障碍被认为是 通过重要途径如血管内皮细胞的调节异常， 内皮生长因子（VEGF）信号传导。目前用于临床的诊断和预后生物标志物 实践（循环脑钠肽，BNP）是血压升高的非特异性标志物， 与疾病严重程度（平均肺动脉压、mPAP和肺血管压力）相关， 耐药，PVR）。因此，迫切需要开发新的PoPH特异性生物标志物， 具有诊断和预后价值。下一代测序可以分离和研究相关的星状和 PoPH中的内皮细胞群，可能影响重要的信号通路（如VEGF）， 有助于PoPH的发病机制。 NIH K23提案的目的是使用多学科方法，结合综合的下一步 肝组织的世代测序分析与生物储存验证，以开发新的PoPH特异性 具有诊断和预后价值的循环肽生物标志物。我们将通过应用 对来自PoPH和非PoPH肝硬化患者的肝组织和血清样品进行单核RNA测序， 专注于生物学上合理的途径，如VEGF信号传导，以确定新的疾病特异性 生物标志物。我们将使用现有的生物样本和临床数据来验证这些生物标志物。 大型良好表型疾病生物储存库，如PAH国家生物样本和数据 仓库。我们的初步数据已经确定了循环VEGF 1受体蛋白（FLT 1）和蛋白激酶 C α亚基（PRKCA）是一种有希望的具有诊断价值的PoPH特异性候选生物标志物。使用 BNP作为对照，我们将完成以下目的：目的1-确定差异基因表达 目的2 -开发FLT 1和PRKCA作为能够区分 肝硬化PoPH并评估PoPH疾病严重程度;目的3 -开发FLT 1和PRKCA作为预测 PoPH治疗反应的生物标志物。该项目与公共卫生密切相关，因为 PoPH和慢性肝病的发病率和患病率增加以及临床意义。成功 这些目标的完成将开发具有临床价值的新型PoPH特异性生物标志物，培养候选人， 进一步开发这些生物标志物作为PoPH的风险分层工具和治疗靶点， 提高肝病合并肺血管病患者的临床护理水平。

PROJECT SUMMARY/ABSTRACT Portopulmonary Hypertension (PoPH) is a type of pulmonary arterial hypertension (PAH) that occurs exclusively in patients with underlying liver disease. PoPH exhibits the highest morbidity and mortality of all PAH subtypes, affecting 10% of all chronic liver disease patients, but the mechanisms that drive disease pathogenesis are poorly understood. Liver portal hypertension and hepatocellular dysfunction are believed to contribute to vascular remodeling in PoPH through dysregulation of important pathways such as vascular endothelial growth factor (VEGF) signaling. The current diagnostic and prognostic biomarker used in clinical practice (circulating brain natriuretic peptide, BNP) is a nonspecific marker of elevated pressure and weakly correlated with disease severity (mean pulmonary arterial pressure, mPAP, and pulmonary vascular resistance, PVR) in PoPH. Consequently, there is a critical need to develop new PoPH-specific biomarkers with diagnostic and prognostic value. Next generation sequencing can isolate and study relevant stellate and endothelial cell populations in PoPH, that are likely to affect important signaling pathways (such as VEGF) and contribute to the pathogenesis of PoPH. The purpose of this NIH K23 proposal is to use a multidisciplinary approach combining integrated next generation sequencing analysis of liver tissue with biorepository validation to develop novel PoPH-specific circulating peptide biomarkers with diagnostic and prognostic value. We will accomplish this goal by applying single nuclear RNA sequencing to liver tissue and serum samples from PoPH and non-PoPH cirrhotic patients, focusing on biologically plausible pathways such as VEGF signaling, to identify novel disease-specific biomarkers. We will validate these biomarkers using biological samples and clinical data obtained from existing large well-phenotyped disease biorepositories such as the PAH National Biological Sample and Data Repository. Our preliminary data has identified circulating VEGF1 receptor protein (FLT1) and Protein Kinase C Alpha subunit (PRKCA) as a promising PoPH-specific candidate biomarkers with diagnostic value. Using BNP as a comparator, we will complete the following aims: Aim 1– Determine the differential gene expression of PoPH endothelial and stellate cells; Aim 2 – Develop FLT1 and PRKCA as biomarkers able to discriminate PoPH from liver cirrhosis and assess PoPH disease severity; Aim 3 – Develop FLT1 and PRKCA as predictive biomarkers of treatment response in PoPH. This project is highly relevant to public health because of the increasing incidence and prevalence, and clinical significance of PoPH and chronic liver disease. Successful completion of these aims will develop novel PoPH-specific biomarkers with clinical value, train the candidate to further develop these biomarkers as risk-stratification tools and therapeutic targets in PoPH, and ultimately improve the clinical care of patients with pulmonary vascular disease due to liver disease.