Dubrow R, Yannielli L
Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, Connecticut.
Am J Gastroenterol. 1992 Jul;87(7):854-8.
To identify fecal proteins that might prove useful in the early detection of colorectal cancer, we used sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and protein immunoblotting to compare the fecal protein patterns of stool supernatants from 10 patients with colorectal cancer with those of 12 controls. SDS-PAGE followed by Coomassie blue staining revealed two heavily stained bands in the majority of cancer stools that were not present in control stools. These bands proved to be human hemoglobin and human albumin by protein immunoblotting. No other consistent differences between the cancer and control stools were observed on the stained gels. The stool supernatants were probed for several other blood proteins by protein immunoblotting. Carbonic anhydrases I and II were more abundant in the cancer stools; alpha 1-antitrypsin appeared equally in cancer and control stools. Further work is needed to determine whether measurement of fecal carbonic anhydrase can be useful for early detection of colorectal cancer.
为了鉴定可能对结直肠癌早期检测有用的粪便蛋白质，我们使用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）和蛋白质免疫印迹法，比较了10例结直肠癌患者粪便上清液与12例对照者粪便上清液的蛋白质模式。SDS-PAGE后用考马斯亮蓝染色显示，大多数癌性粪便中有两条染色较深的条带，而对照粪便中不存在。通过蛋白质免疫印迹法证实这些条带为人血红蛋白和人白蛋白。在染色凝胶上未观察到癌性粪便与对照粪便之间的其他一致差异。通过蛋白质免疫印迹法检测粪便上清液中的其他几种血液蛋白质。碳酸酐酶I和II在癌性粪便中含量更高；α1-抗胰蛋白酶在癌性粪便和对照粪便中含量相当。需要进一步开展工作以确定检测粪便碳酸酐酶是否有助于结直肠癌的早期检测。
