Markers of Early Pancreatic Cancer

描述(申请人提供)：该项目的总体目标是开发新的胰腺癌血清和胰液标记物，可用于诊断有疾病症状的患者，并识别早期无症状胰腺癌患者。NCI项目审查小组(PRO)将其列为研究重点--“确定和发展早期发现胰腺癌及其‘先兆’的监测和诊断方法”。一系列灵敏、特异的胰腺癌标志物将极大地促进胰腺癌的早期诊断和早期发现。我们将检查三种标记物策略，旨在检测血清或胰液中的胰腺肿瘤。每个目标都侧重于特定的、特征良好的蛋白质或DNA标记，这些标记已经成为第二阶段研究的主题。血清MIC-1(AIM#L)对CA19-9具有较高的总体诊断敏感性。对于第二个目标，我们将重新评估胰腺癌的一个众所周知的标记物，突变的KRAS。以前的研究发现，在胰腺中检测到它缺乏必要的特异性来区分胰腺癌和胰腺炎。为了克服这种疾病特异性的缺乏，我们开发了一种新的、高度敏感和特异的检测方法(“LigAmp”)来检测和量化突变的点突变，如突变的KRAS。我们的初步第二阶段研究表明，定量突变KRAS显著提高了其诊断实用价值。对于目标3，我们将使用一种新的突变检测方法，当P53和pi 6等基因在临床样本(如胰液)中低浓度存在时，可以检测出它们的未知突变(有限稀释-PCR，或“LD-PCR”和异源双链分析(HA))。我们将3A的结果与使用P53基因芯片获得的结果进行比较。我们将追求的具体目标是：目的；1：确定血清MIC-1的敏感性和特异性；1A：作为早期胰腺癌的标志物。IB：在发生这种疾病的高危人群中作为无症状胰腺癌的预测因子，以及1C；确定不过度表达MIC-1的胰腺癌的生物学和临床意义。目标2A：开发和验证5个KRAS和1个BRAF LigAmp分析，以生产用于AIM 2B的面板。2B：证明LigAmp在检测和量化胰腺癌患者和正常对照患者胰液和血清中KRAS2和BRAF突变的诊断价值。目的：探讨一种新的检测胰腺疾病或胰腺癌筛查患者胰液中低丰度p53和pI6基因突变的新方法(限制性稀释聚合酶链式反应或异源双链分析)的诊断价值。比较Aim 3A(LD/PCR/HA)和P53基因芯片检测胰液中P53突变的能力。我们还将确定结合从这三个目标得出的标记物结果的诊断效用。

DESCRIPTION (provided by applicant): The overall goal of this project is to develop new serum and pancreatic juice markers of pancreatic cancer that can be used to diagnose patients with symptoms of their disease and to identify patients with early asymptomatic pancreatic cancer. The NCI Program review group (PRO) cited as a research priority- "to identify and develop surveillance and diagnostic methods for the early detection of pancreatic cancer and its' precursors'". A panel of sensitive and specific markers of pancreatic adenocarcinoma would greatly facilitate the early diagnosis and early detection of this disease. We will examine three marker strategies that aim to detect pancreatic neoplasia in serum or in pancreatic juice. Each aim focuses on specific, well-characterized protein or DNA markers that have already been the subject of phase 2 studies. One marker, serum MIC-1 (aim #l) has superior overall diagnostic sensitivity to CA19-9. For aim #2 we will re-evaluate a well-known marker of pancreatic cancer, mutant KRAS. Previous studies have found that its detection in the pancreas lacks the necessary specificity to differentiate pancreatic cancer from pancreatitis. To overcome this lack of disease specificity, we have developed a novel, highly sensitive and specific assay ("LigAmp") to detect and quantify point mutations such as mutant KRAS. Our preliminary phase 2 studies indicate that quantifying mutant KRAS significantly improves its diagnostic utility. For aim #3 we will use a novel mutation detection approach that can detect unknown mutations in genes such as p53 and pi 6 when they are present at low concentration in clinical samples such as pancreatic juice (limiting dilution-PCR, or "LD-PCR" and heteroduplex analysis (HA)). We will compare the results of 3A with those obtained using p53 Gene chips. The specific aims we will pursue are: Aim; 1: To determine the sensitivity and specificity of serum MIC-1; 1A: as a marker of early pancreatic cancer. IB: as a predictor of asymptomatic pancreatic cancer in a population at high risk of developing this disease, and 1C; to determine the biological and clinical significance of pancreatic cancers that do not overexpress MIC-1. Aim 2A: To develop and validate five KRAS and one BRAF LigAmp assays to produce a panel for use in aim 2B. 2B: To demonstrate the diagnostic utility of LigAmp to detect and quantify KRAS2 and BRAF mutations in pancreatic juice and in serum from patients with pancreatic cancer and appropriate controls. 3A; To demonstrate the diagnostic utility of a novel assay (Limiting dilution PCR or LD-PCR with Heteroduplex analysis (HA)) to detect and quantify low abundance p53 and pi 6 mutations in the pancreatic juice of patients with pancreatic disease or undergoing pancreatic cancer screening. 3B; To compare the results of aim 3A (LD/PCR/HA) with p53 GeneChip for their ability to detect p53 mutations in pancreatic juice. We will also determine the diagnostic utility of combining the results of the markers derived from these 3 Aims.