结直肠癌肝转移患者尿蛋白Cathepsin D的检测和意义

Significance of detection of urinary cathepsin D in patients with colorectal cancer liver metastasis

目的:本文旨在寻找一种更经济的方式来监测结直肠癌肝转移,我们尝试使用硝酸纤维素膜富集结直肠癌肝转移患者和结直肠癌患者尿蛋白,并在尿蛋白中检测Cathepsin D是否可以作为结直肠癌肝转移尿蛋白标志分子.方法:收集结直肠癌肝转移患者及结直肠癌患者随机中段尿,经抽滤法将尿蛋白富集在硝酸纤维素膜上.用蛋白免疫印迹方法检测硝酸纤维素膜上洗脱下来的尿蛋白中的Cathepsin D含量,并通过尿肌酐校正尿蛋白中的Cathepsin D含量.结果:硝酸纤维素膜可以富集到质量较好的尿蛋白,并可用于后续研究.与健康对照和结直肠癌患者相比,Cathepsin D在结直肠癌肝转移患者尿蛋白中表达升高.经尿肌酐校正后,结直肠癌肝转移患者样本中Cathepsin D含量显著高于健康对照和结直肠癌患者样本(P<0.01).结论:硝酸纤维素膜富集法可以快速富集到高质量的尿蛋白.经尿肌酐校正后,结直肠癌肝转移患者尿蛋白中Cathepsin D含量显著高于健康个体和结直肠癌患者,提示Cathepsin D可能是潜在的结直肠癌肝转移标志物.

AIM：To find a more economical method for monitoring colorectal carcinoma liver metastasis by detecting whether cathepsin D can be used as a urinary biomarker of colorectal carcinoma liver metastasis.METHODS：Random mid-stream urine samples were collected from patients with colorectal carcinoma with or without liver metastasis.The urine protein was enriched on NC membrane through pumping filtration,and Western blot was used to detect the concentration of cathepsin D after elution.Urine creatine was used to normalise the result.RESULTS：The enriched protein showed a good quality and Western blot results indicated that the concentration of cathepsin D in urine of patients with colorectal carcinoma liver metastasis was significantly higher than those of healthy controls and CRC patients without metastasis.CONCLUSION：The method of urine protein enrichment allows to obtain high quality urine protein quickly,and urinary cathepsin D may serve as a potential biomarker of colorectal carcinoma liver metastasis.