Markers for HCV-related HCC: plasma profiling, targeted strategies and validation

描述（由申请人提供）：据报道，世界范围内肝细胞癌（HCC）发病率呈上升趋势，这与人群中丙型肝炎病毒（HCV）感染的高流行率有关。目前迫切需要更好的HCC诊断方法。我们之前的研究为潜在肝脏疾病的病因学与HCC中基因/蛋白表达模式的差异之间的关联提供了证据。他们还提供了对HCC发展中潜在重要的蛋白质亚型的新见解。我们最近开发了一种方法来全面和定量地分析复杂样品的蛋白质组，我们已经将这种方法应用于肝脏和血浆。该方法基于对完整蛋白质的广泛分离，在肝脏中鉴定了大约9000种蛋白质，鉴定的置信度很高，包括低丰度蛋白质，如细胞因子、趋化因子和受体。基于光谱计数的丰度评分归因于每个鉴定的蛋白质。计算的丰度分数似乎是蛋白质丰度的一个很好的估计。在血浆中，在生物标志物浓度范围（pg/ml）内鉴定了许多低丰度蛋白，并且在肝组织和血浆中鉴定了疾病阶段（纤维化和早期HCC）特异性蛋白。有趣的是，在组织中观察到的丰度变化与在血浆中观察到的随疾病分期变化的选择性蛋白质的丰度变化之间没有相关性。总之，该方法在复杂生物混合物（如哺乳动物组织和血浆）的蛋白质组学分析方面达到了前所未有的深度，允许鉴定与疾病相关的蛋白质变化，并表明基于组织的发现和基于血浆的发现研究可能会产生不同的结果。本提案的目的是利用该方法鉴定hcv相关HCC的蛋白质生物标志物，可用于早期发现和诊断。我们将应用这种方法来鉴定最近进展为HCC的丙型肝炎相关肝硬化患者和未发生HCC的丙型肝炎相关肝硬化患者血浆中表达水平不同的蛋白质及其亚型。在本研究的发现部分中确定的最有希望的候选药物将被用于验证。我们将建立这些蛋白质生物标志物单独和联合的敏感性和特异性，用于早期检测HCC。公共卫生相关性：据报道，世界范围内肝细胞癌（HCC）发病率呈上升趋势，这与人群中丙型肝炎病毒（HCV）感染的高发有关。目前迫切需要更好的HCC诊断方法。本提案的目的是开发一套强大的HCC生物标志物，可用于早期检测和诊断。

DESCRIPTION (provided by applicant): A trend of increasing rates of hepatocellular carcinoma (HCC) has been reported worldwide, that is related to the high prevalence of hepatitis C virus (HCV) infection in the population. Better means for HCC diagnosis are urgently needed. Our prior studies provided evidence for an association between the etiology of the underlying liver disease and differences in patterns of gene/protein expression in HCC. They also offered new insights into protein isoforms that are potentially important in the development of HCC. We recently developed a method to comprehensively and quantitatively profile the proteome of a complex sample and we have applied this method to the liver and to plasma. This method, based on extensive fractionation of intact proteins, resulted in the identification of approximately 9,000 proteins in the liver, identified with high confidence and including low-abundance proteins such as cytokines, chemokines and receptors. An abundance score based on spectral counts was attributed to each identified protein. The calculated abundance scores appeared to be a good estimate of protein abundance. In the plasma, numerous low-abundance proteins in the biomarker concentration range (pg/ml) were identified and proteins specific to disease stage (fibrosis and early HCC) were identified in liver tissue as well as in plasma. Interestingly, there was no correlation between the abundance changes observed in the tissues and the abundance changes observed in the plasma for selective proteins changing with disease stage. In conclusion, this method reached a depth in proteomic profiling not previously reported for complex biological mixtures such as mammalian tissue and plasma, allowed for the identification of protein changes associated with disease and suggested that tissue-based discovery and plasma-based discovery studies may lead to different results. The purpose of this proposal is to utilize this method for the identification of protein biomarkers for HCV-related HCC that could be used for early detection and diagnosis. We will apply this approach to identify proteins and their isoforms that differ in expression levels between plasma obtained from patients with HCV-related cirrhosis that have recently progressed to HCC and patients with HCV-related cirrhosis with no HCC. The most promising candidates identified in the discovery component of this research will be targeted for validation. We will establish the sensitivity and specificity of these protein biomarkers individually and in combination, for detecting HCC early. PUBLIC HEALTH RELEVANCE: A trend of increasing rates of hepatocellular carcinoma (HCC) has been reported worldwide, that is related to the high prevalence of hepatitis C virus (HCV) infection in the population. Better means for HCC diagnosis are urgently needed. The purpose of this proposal is the development of a robust set of biomarkers for HCC that could be used for early detection and diagnosis.