Tissue and Tumor Specific Glycosylation of Proteins

描述（由申请人提供）：蛋白质糖基化模式的改变和血清蛋白水平的升高通常是人类疾病的标志。血清糖蛋白γ -谷氨酰转肽酶（GGT）水平升高常见于肝脏和胰腺肿瘤患者以及非恶性肝脏和胰腺疾病患者。越来越多的数据表明，GGT具有组织特异性和肿瘤特异性糖型，可用于区分癌症患者和其他病理患者。我的研究将集中在鉴别和表征组织和肿瘤特异性聚糖的GGT。本研究有三个具体目标，其中包括使用最先进的荧光高效液相色谱和质谱技术进行糖分析。第一个具体目标是鉴定从正常胰腺和肝脏组织分离的GGT上的组织特异性糖型。第二个具体目标是鉴定从胰腺和肝脏肿瘤分离的GGT上的肿瘤特异性聚糖种类，以及这些恶性肿瘤患者血清中脱落的GGT上的肿瘤特异性聚糖种类。本提案的第三个具体目标是开发针对组织和肿瘤特异性GGT糖表位的抗体，并评估这些抗体用于检测来自非患病个体和诊断为胰腺腺癌、肝细胞癌和胰腺和肝脏非恶性疾病的患者血清中组织和肿瘤特异性GGT物种的敏感性和特异性。这些研究也将为肿瘤发生过程中GGT从细胞膜释放到血清中的机制提供见解。胰腺癌或肝癌的及时准确诊断是提高治疗效果的关键。这项工作将为开发一种基于血清的免疫测定方法奠定基础，该方法可以利用流入血清的GGT上的糖表位来早期检测这些恶性肿瘤。概要：诊断为胰腺癌或肝癌的患者生存率非常低。这在很大程度上是由于这两种形式的癌症通常在患者开始出现疾病症状之前不会被发现，而这些症状通常与疾病的晚期阶段有关。我建议鉴定和表征新的血液标记物，这些标记物可用于开发胰腺癌和肝癌早期检测的筛选试验，因为癌变组织对治疗性治疗反应最灵敏。第二页在表格第二页的底部连续编号

DESCRIPTION (provided by applicant): Altered patterns of protein glycosylation and increased levels of serum proteins are often hallmarks of human diseases. Elevated serum levels of the glycoprotein gamma-glutamyl transpeptidase (GGT) are commonly seen in patients with tumors of the liver and pancreas and in patients with non malignant forms of liver and pancreatic diseases. An accumulating body of data indicates that GGT possesses tissue-specific and tumor-specific glycoforms that could be used to distinguish patients with cancer from those with other pathologies. My study will focus on the identification and characterization of tissue- and tumor-specific glycans on GGT. This study has three specific aims, which incorporate the use of state-of-the-art fluorescent HPLC and mass spectrometric techniques for glycoanalyses. The first specific aim is to identify tissue-specific glycoforms on GGT isolated from normal pancreas and liver tissue. The second specific aim is to identify tumor-specific glycan species on GGT isolated from tumors of the pancreas and liver and on GGT shed into the serum of patients with these malignancies. The third specific aim of this proposal is to develop antibodies against tissue- and tumor-specific glycoepitopes on GGT and to evaluate the sensitivity and specificity of these antibodies for detecting tissue- and tumor-specific GGT species in sera derived from non-diseased individuals and patients diagnosed with pancreatic adenocarcinoma, hepatocellular carcinoma, and non-malignant diseases of the pancreas and liver. These studies will also provide insight into the mechanism by which GGT is released from cellular membranes into serum during tumorigenesis. The timely and accurate diagnosis of pancreatic or liver cancer is critical for maximizing the efficacy of therapeutic treatments. This work will establish a foundation for the development of a serum-based immunoassay for the early detection of these malignancies using glycoepitopes on GGT shed into the serum. Lay summary: Survival rates for patients diagnosed with either pancreatic or liver cancer are very low. This is largely due to the fact that these two forms of cancer typically go undetected until patients begin showing disease symptoms, which are most often associated with advanced stages of the disease. I propose to identify and characterize novel blood markers that can be used to develop screening tests for the early detection of pancreatic and liver cancer at a stage when the cancerous tissues are the most responsive to therapeutic treatments. Page 2 Number pages consecutively at the bottom throughout Form Page 2