Biomarker for Hepatocellular Carcinoma

描述(申请人提供)：人肝细胞癌是慢性肝病和肝硬变最严重的并发症之一。更令人不安的是，观察到从确诊时起的平均预期寿命约为8至10个月。在美国，肝癌的发病率已经开始增加，这主要是由于慢性丙型肝炎(丙型肝炎)感染所致。此外，随着包括II型糖尿病和胰岛素抵抗在内的肥胖症的流行，非酒精性脂肪性肝炎(NASH)的出现已经开始在这种毁灭性疾病的发病机制中发挥更大的作用，因为肝硬化是肝细胞癌的危险因素。最近，卫生保健专业人员普遍关注肝细胞癌的增加，以及缺乏导致或有助于早期诊断和治疗的最佳筛查技术，以期改善这种几乎一致致命的疾病的预后。因此，这项建议的目的是验证一种新的标记物，该标记物可能对肝细胞癌的早期诊断有用。在这方面，我们已经通过与单抗结合和表达克隆的方法确定了在肝细胞癌中增强的细胞表面蛋白标记物。编码该蛋白的基因已经被克隆，并被分子鉴定为天冬氨酸羟基酶(HAAH)，它似乎在大多数(&gt；90%)乙肝(&gt；)和丙型肝炎相关的肝细胞癌中高表达。此外，这种蛋白似乎存在于此类患者的血清中。因此，我们建立了以重组蛋白为标准检测血清中C端和N端片段以及全长HAAH的免疫分析方法。由于这种酶是在细胞表面表达的，我们最近开发了针对该分子不同区域的人源单链抗体和抗体。这些试剂将用于人类肝癌小鼠模型的生物分布研究，以靶向肿瘤。有证据支持HAAH基因是一种新的肝癌生物标志物的假说，因为HAAH基因的表达似乎与该病的发病机制高度相关。我们计划做以下工作。具体目的1.验证HAAH作为肝细胞癌的生物标志物。特异性目的2.进一步鉴定人源单链抗体片段和抗AAH抗体。这些新的基于单抗的检测方法有望用于肝癌的早期检测，人抗HAAH抗体可作为靶向试剂用于肝细胞癌的特异性检测。

DESCRIPTION (provided by applicant): Human hepatocellular carcinoma (HCC) is one of the most serious complications of chronic liver disease and cirrhosis. Even more disturbing is the observation that the average life expectancy from the time of diagnosis is approximately eight to ten months. The incidence of HCC has begun to increase in the United States principally due to the contribution of chronic hepatitis C (HCV) infection. In addition, with the obesity epidemic including Type II diabetes and insulin resistance, the emergence of non-alcoholic steatohepatitis (NASH) has begun to assume a larger role in the pathogenesis of this devastating disease due to the development of cirrhosis, a risk factor for HCC. More recently, there is widespread concern among health care professionals regarding the increase in HCC and the lack of optimal screening techniques that lead to or contribute to early diagnosis and treatment in the hope of improving the prognosis of this almost uniformly fatal disease. Thus, the purpose of this proposal is to validate a new marker that may be useful in the early diagnosis of HCC. In this regard, we have identified by monoclonal antibody (mAb) binding and expression cloning, a cell surface protein marker that is enhanced in HCC tumors. The gene encoding for this protein has been cloned and molecularly identified as aspartyl (asparaginyl) (¿-hydroxylase (HAAH) which appears to be highly expressed in most (>90%) hepatitis B (HBV) and HCV related HCC. Furthermore, this protein appears to be present in serum of such patients. Thus, we have established immunoassays to detect C and N terminal fragments as well as full length HAAH in serum using recombinant proteins as standards. Because this enzyme is expressed on the cell surface, we have recently developed human scFv and IgG antibodies directed against the various region of the molecule. These reagents will be used in biodistribution studies to target tumors in murine models of human HCC. Evidence will be presented to support the hypothesis that HAAH gene is a novel biomarker for HCC since expression appears to be highly associated with the pathogenesis of the disease. We plan to do the following. Specific Aim 1. Validate HAAH as a biomarker for HCC. Specific Aim 2. Further characterize human scFv fragments and IgG anti-AAH antibodies. It is likely that these new mAb based assays will be useful for the early detection of HCC and human anti-HAAH antibodies may be employed as targeting reagents for the specific detection of HCC in the liver.