Wilson A J, Gibson P R
Department of Medicine, University of Melbourne, Royal Melbourne Hospital, Victoria 3050, Australia.
Gut. 2000 Jul;47(1):105-11. doi: 10.1136/gut.47.1.105.
Migration of colonic epithelial cells is important for mucosal repair following injury. The urokinase (u-PA) system regulates migration in other cell types.
To examine the role of u-PA and its receptor (u-PAR) in colonic epithelial cell migration.
Migration was assessed over 24 hours in circular wounds made in confluent monolayers of LIM1215 and Caco-2 human colon cancer cells. The function of u-PA and u-PAR was ablated with antisense oligonucleotides to block expression, with synthetic u-PA peptides to block interaction, and with aprotinin to block u-PA mediated proteolysis.
Migration was stimulated two to threefold by exogenous u-PA, an effect dependent on u-PAR binding but independent of u-PA mediated mitogenesis and proteolysis. Expression of u-PA and u-PAR was inhibited by 80% by the appropriate antisense oligonucleotide. Basal migration and the motogenic effects of butyrate, epidermal growth factor, and phorbol-12-myristate-13-acetate were suppressed by the u-PAR antisense oligonucleotide (40-60%) but were at best minimally affected following inhibition of u-PA expression and binding.
In an in vitro model of wounded colonic epithelium, u-PAR promotes cell migration through mechanisms that are not exclusively dependent on u-PA binding. Therefore, u-PA and u-PAR may contribute to colonic mucosal repair in vivo.
结肠上皮细胞迁移对于损伤后的黏膜修复很重要。尿激酶（u-PA）系统调节其他细胞类型的迁移。
研究u-PA及其受体（u-PAR）在结肠上皮细胞迁移中的作用。
在LIM1215和Caco-2人结肠癌细胞汇合单层形成的圆形伤口中评估24小时内的迁移情况。用反义寡核苷酸阻断表达、用合成u-PA肽阻断相互作用以及用抑肽酶阻断u-PA介导的蛋白水解来消除u-PA和u-PAR的功能。
外源性u-PA使迁移增加2至3倍，该效应依赖于u-PAR结合，但独立于u-PA介导的有丝分裂和蛋白水解。适当的反义寡核苷酸使u-PA和u-PAR的表达抑制80%。u-PAR反义寡核苷酸抑制基础迁移以及丁酸盐、表皮生长因子和佛波醇-12-肉豆蔻酸酯-13-乙酸酯的促迁移作用（40 - 60%），但在抑制u-PA表达和结合后，影响至多最小。
在受伤结肠上皮的体外模型中，u-PAR通过不完全依赖于u-PA结合的机制促进细胞迁移。因此，u-PA和u-PAR可能在体内对结肠黏膜修复有作用。
