Biomarker Discovery in Portopulmonary Hypertension

项目摘要/摘要 门静脉高压症(PoPH)是一种发生于 仅适用于有潜在肝病的患者。POPH的发病率和死亡率是所有疾病中最高的 PAH亚型，影响10%的慢性肝病患者，但驱动疾病的机制 其发病机制目前尚不清楚。肝门脉高压和肝细胞功能障碍被认为是 通过血管等重要通路的失调参与POPH的血管重塑 内皮生长因子(VEGF)信号转导。目前临床上使用的诊断和预后生物标志物 实践(循环脑利钠肽，BNP)是血压升高和虚弱的非特异性标志物 与疾病严重程度(平均肺动脉压、mPAP和肺血管)相关 阻力，PVR)在POPH。因此，迫切需要开发新的POPH特异性生物标记物 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)和 参与了POPH的发病机制。 NIH K23提案的目的是使用多学科方法结合集成的NEXT 应用生物信息库验证的肝组织发生序列分析以开发新的POPH特异性 具有诊断和预后价值的循环多肽生物标志物。我们将通过申请来实现这一目标 POPH和非POPH肝硬变患者肝组织和血清标本的单核RNA测序 专注于生物学上合理的途径，如血管内皮生长因子信号，以确定新的疾病特异性 生物标志物。我们将使用从现有生物样本和临床数据中获得的生物样本和临床数据来验证这些生物标志物 大型表型良好的疾病生物库，如PAH国家生物样本和数据 存储库。我们的初步数据已经确定循环中的VEGF1受体蛋白(Flt1)和蛋白激酶 Cα亚基(PRKCA)是一种具有诊断价值的POPH特异性候选生物标志物。vbl.使用 BNP作为比较器，我们将完成以下目标：目标1-确定差异基因表达 POPH内皮细胞和星状细胞；目标2-开发Flt1和PRKCA作为能够区分的生物标志物 来自肝硬变的POPH并评估POPH疾病的严重程度；目标3-发展Flt1和PRKCA作为预测 POPH治疗反应的生物标志物。该项目与公共卫生高度相关，因为 POPH和慢性肝病的发病率和患病率增加及其临床意义。成功 这些目标的完成将开发具有临床价值的新型POPH特异性生物标记物，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，并最终 提高肝病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.