Identification of factors involving chemotherapy resistance in pancreatic cancer patients by Protein Chip system for developing prediction system of chemotherapy response.

用抗Annexin II抗体测定血清Annexin II水平利用双向凝胶电泳法比较长期用药吉西他滨处理的胰腺癌细胞株与野生型细胞株的蛋白质表达谱。我们发现Annexin II在化疗耐药的细胞系中高表达，但在野生型细胞中不表达。这表明Annexin II在建立癌细胞的化疗耐药性方面发挥了作用。检测胰腺癌患者血清Annexin II水平可作为判断胰腺癌患者预后的指标。现在，我们建立了使用蛋白质芯片系统(CYPHAGEN)来检测血清Annexin II水平的系统。该系统利用激光光谱对样品中的多肽进行解析，能够测量样品中多肽的表达水平。为了获得特定的血清Annexin II水平，我们对…进行了修改更多的蛋白芯片表面有抗Annexin II抗体。使用该系统，抗体只捕获了血清中整个蛋白中的Annexin II，即使在表达水平很低的情况下，我们也能够准确地评估该目标蛋白的浓度。我们正在尝试检测胰腺癌患者血清Annexin II的水平，并分析这一血清水平是否与吉西他滨治疗后患者的预后相一致。为此，我们已经采集了患者手术或化疗前后的血清样本，并正在尝试使用相同的系统来检测尿液Annexin II的水平。利用这些技术，我们现在期待着我们可以选择预后改善的胰腺癌患者，并避免对治疗无效的患者使用这种药物。对于这些患者，我们会用其他疗法的另一种药物来治疗，比如放射治疗。该系统将为患者的选择提供好处，避免浪费这些患者的宝贵时间和成本。较少

Measurement of serum Annexin II level using anti-Annexin II antibodyUsing 2-D gel electrophoresis, we compared the protein profiling expressed in pancreatic cancer cell line which is resistant against treatment with anti cancer drug, gemcitabine, established by treating cells with the drug for long time with wild type cell line. We identified Annexin II is highly expressed in cell line with chemo-resistance, but not in wild type cells. This indicated that Annexin II has a role in establishing chemo-resistance in cancer cells. This also suggested that measurement of serum Annexin II level in pancreatic cancer patients may indicate the prognosis of the patients with treatment of this medicine. We now established the system to measure the serum level of Annexin II using Protein Chip System (CYPHAGEN). This system resolve the peptide in the sample using laser spectrum and enable to measure the expression level in the sample. To obtain specifically the serum level of Annexin II, we modified … More the surface of the protein chip plate with anti-Annexin II antibody. Using this system, only Annexin II within the whole protein in the serum is captured with the antibody, and we are able to evaluate the concentration of this target protein with precise value even though the expression level is very low. We are now trying to measure Annexin II serum level of the pancreatic cancer patients and analyze whether this serum level is collate with patients prognosis after gemcitabine treatment. For this purpose, we already collected serum samples from patients before and after operation or chemotherapy.We also are trying to measure the urine levels of Annexin II using same system. Using these technique, we are now expecting that we can select the pancreatic cancer patients whose prognosis gemcitabine will improve and avoid the use of this medicine for patients who will not respond the therapy. To these patients, we will treat them with another medicine of other therapies, such as radiation. This system will provide the benefits for selecting the patients and will avoid the wasting precious time and cost of these patients. Less