前列腺增生的尿液蛋白质组学分析

目的在临床前列腺特异性抗原(prostate-specific antigen,PSA)升高的情况下,特别是前列腺特异性抗原在4μg/L至10μg/L时,前列腺增生和前列腺癌的鉴别诊断很难,本实验对前列腺增生患者、前列腺癌患者和健康对照的尿液蛋白质双向凝胶电泳图谱进行对比分析,旨在较全面的分析其成分,为临床鉴别诊断提供依据。方法用丙酮沉淀蛋白的方法对前列腺增生患者、前列腺癌患者和健康对照尿液中的蛋白质进行浓缩,再用双向凝胶电泳技术分离蛋白质样品,CANON G9照相获取图像,PDQuest2D分析软件对图像进行背景消减、斑点检测、匹配、斑点位置重复性的系统分析,寻找差异表达蛋白质。在此基础上用基质辅助激光解吸电离飞行时间质谱(MALIDI-TOF)进行肽指纹图谱鉴定,并进行生物信息学分析。结果通过前列腺增生、前列腺癌和健康对照尿液双向凝胶电泳图的对比分析,获得前列腺增生差异蛋白质点,选取其中20个做质谱和生物信息学分析,最终分离鉴定出血清白蛋白、视黄醇结合蛋白前体等17种有效蛋白。结论通过实验条件的优化,应用蛋白质组学方法分析前列腺增生患者尿液蛋白质的组成成分是可行的,为研究前列腺增生患者尿液检测特异标志物提供了基础资料,为今后鉴别前列腺增生和前列腺癌提供了有益的依据,同时也为解决临床误诊难题提供了思路。

Urinary Proteomic Analysis for Diagnosis and Differential Diagnosis of Prostatic Hyperplasia

Objective Prostate cancer and benign prostatic hyperplasia(BPH) can not be differentiated by serum prostate-specific antigen (PSA) in clinical medicine, especially when the level of PSA is in the range of 4 μg/L~10 μg/L. To find out some methods for differential diagnosis, proteomic analysis was made on proteins precipitated from urine specimens of patients with benign prostatic hyperplasia and prostate cancer. Methods Proteins were precipitated with acetone from urine specimens of 3 cases with benign prostatic hyperplasia, 3 cases with prostate cancer, and 3 healthy persons. Then proteins were separated with two-dimensional polyacrylamide gel electrophoresis(2D-PAGE). The proteins were identified by peptide mass fingerprinting. Results Via the analysis, 20 spots were obtained and a total of 17 different proteins were identified, including serum albumin, plasma retinol-binding protein precursor etc. Conclusion Proteomic analysis of urinary protein is a promising tool to study benign prostatic hyperplasia and may become a potential diagnostic biomarker.