【作者】 孙玉琳；

【导师】 赵晓航；

【作者基本信息】 中国协和医科大学 ， 细胞生物学， 2008， 博士

【摘要】 肝脏是机体物质代谢、能量转换和免疫调节的重要器官,生物学、化学致癌因素和遗传因素与肝脏肿瘤,如肝细胞肝癌(Hepatocellular carcinomas,HCC)的发生发展相关。由于缺乏有效的早期诊断方法,HCC的五年生存率不足10%。虽然甲胎蛋白(alpha-fetoprotein,AFP)是目前临床上应用最为广泛的HCC诊断标志物,但是至少20-30%的HCC患者血清AFP水平不升高。因此,目前迫切需要寻找更为敏感和特异或能与AFP联用使用的HCC诊断标志。本研究对比分析不同AFP表达特性的肝癌和正常肝细胞系的蛋白质组成差异,鉴定到166个差异表达蛋白质,从中选择5个蛋白质进行深入的组织学和血清学验证,发现Annexin A2和TGM2(Tissue transglutaminase 2)有可能成为HCC潜在的候选标志分子。同时,参与了人类肝脏蛋白质组计划(Human liver proteomeproiect,HLPP)中健康肝标准和样本采集方法的制定、健康肝标本库的建立和表达谱数据的生物学意义解读等内容,发现表达谱数据充分反映了禁食状态下健康肝脏的生理和代谢特点,为深入研究疾病肝的蛋白质组改变提供了重要的参照数据。胰腺癌是恶性程度极高的实体瘤之一,由于起病隐匿,进展迅速,缺乏早期特异性症状和有效的治疗手段,五年生存率不足5%。目前常用的标志CA19-9灵敏度和特异度不高,诊断价值有限。为寻找新的胰腺癌血清标志,利用无血清器官培养方法,富集并浓缩了胰腺癌细胞分泌、释放到血液中的肿瘤相关蛋白,构建了胰腺癌相关的游离蛋白表达谱。分别在正常胰腺和胰腺导管腺癌中鉴定了150个和533个游离蛋白。生物信息学分析显示,分别有35%和43%的蛋白定位于细胞外和细胞膜,涉及细胞发育、免疫、应激反应等生物学过程,为认识胰腺癌生物学性质及其发生发展机制,发现新的胰腺癌相关标志分子提供重要参考。更多还原

【Abstract】 Liver is an important organ in human being which can carry out a multitude of biochemical reactions and play central roles on metabolism, energy conversion and regulation of immune response. Several infectious agents, chemical carcinogens and genetics factors contributed to the tumorigenesis of liver cancer, such as hepatocellular carcinoma (HCC). The five-year survival rate of HCC was less than 10% due to failure of early diagnosis. Alpha-fetoprotein (AFP) is only an available serologic biomarker for HCC diagnosis, however, about one third of HCC patients present with low levels of serum AFP in which some of the patients were in early stage. Therefore, discovery of additional biomarkers may improve early diagnosis of HCC as well as better understanding the mechanisms underlying tumorigenesis at the clinic. This study quantitatively compared the protein profiles between normal liver and several liver cancer cells corresponding to different AFP expression characteristics. Finally, 166 differentially expressed proteins were identified and five candidates were further verified at histological and serological levels, showing Annexin A2 and Tissue transglutaminase 2 (TGM2) could be served as potential biomarkers of HCC in serum. Meanwhile, we participated in human liver proteome project (HLPP) and involved in makes standard operating procedures for donor screening, sample collection and deciphering the related proteins of bile acid and bilirubin metabolism in the human liver proteome (HLP) dataset. Combined with the results of several experiments, we think the expression profile of HLP is the most comprehensive proteome dataset in human liver, reflecting the metabolic and physiological characteristics of healthy liver at the fasting condition. It gave important references and comparisons to liver diseases even hepatocelluar carcinoma.Pancreatic cancer was one of the most malignant digestive cancers worldwide. Because it was difficult to diagnose at an early stage and lacks of specific symptoms, its 5-year survival rate was less than 5%. CA19-9 was a common used biomarker of pancreatic cancer, but its diagnostic value was limited due to its poor sensitivity and specificity. Therefore, there is an urgent need to identify potential biomarkers for early diagnosis. Conditioned medium of pancreatic cancer and the adjacent normal pancreas organ cultures were collected and the tumor-related secretory proteins were enriched. Finally, 150 and 533 dissociative proteins were identified using thriple replicate shotgun LC-MS/MS strategy. The bioinformatics analysis revealed that about 35% and 43% proteins were localized to extracellular region and plasma membrane. Proteins which were involved in cell growth, immune and stress response might play important roles on the tumorigenesis of pancreatic cancer. This pancreatic cancer-related dissociative protein profile was helpful to search for potential biomarkers for early diagnosis of pancreatic cancer as well as better understand the mechanisms underlying tumorigenesis.更多还原