Steven F S, Anees M, Talbot I C
Department of Biochemistry and Molecular Biology, School of Biological Sciences, University of Manchester, U.K.
Anticancer Res. 1994 Sep-Oct;14(5A):2013-6.
The cell surfaces of normal colonic epithelial cells and colonic carcinoma cells both possess a protease referred to as guanidinobenzoatase (GB). Previous studies have shown that these cells possess two distinct isoenzymic forms of GB which could be distinguished by their selective recognition of cytoplasmic protein inhibitors of GB. In the present study we have used competitive inhibitors of GB to demonstrate the differential inhibition of the GB on normal colonic epithelial cells whilst the GB on colonic carcinoma cell surfaces remains active. The enzymic status of GB on these cells has been determined by challenging the treated cells in frozen sections with a second fluorescent inhibitor, followed by fluorescence microscopic analysis.
正常结肠上皮细胞和结肠癌细胞的细胞表面均拥有一种名为胍基苯甲酸酶（GB）的蛋白酶。先前的研究表明，这些细胞拥有两种不同的GB同工酶形式，可通过它们对GB胞质蛋白抑制剂的选择性识别来区分。在本研究中，我们使用GB的竞争性抑制剂来证明GB对正常结肠上皮细胞的差异性抑制作用，而结肠癌细胞表面的GB仍保持活性。通过用第二种荧光抑制剂对冷冻切片中的处理细胞进行检测，随后进行荧光显微镜分析，确定了这些细胞上GB的酶学状态。
