Kim W H, Nomizu M, Song S Y, Tanaka K, Kuratomi Y, Kleinman H K, Yamada Y
National Institute of Dental Research, National Institutes of Health, Bethesda, MD 20892-4370, USA.
Int J Cancer. 1998 Aug 12;77(4):632-9. doi: 10.1002/(sici)1097-0215(19980812)77:4<632::aid-ijc25>3.0.co;2-6.
We earlier screened overlapping synthetic peptides from the globular domain of the laminin alpha1 chain to identify active sites for cell attachment. We report here that one of the active cell-adhesion peptides, AG-73 (Arg-Lys-Arg-Leu-Gln-Val-Gln-Leu-Ser-Ile-Arg-Thr; RKRLQVQLSIRT) causes B16F10 murine melanoma cells to metastasize to the liver, a site not normally colonized by these cells. Increases in liver metastases and in lung colonization are observed in immune-deficient beige/nude/xid and in C57Bl/6 mice with this peptide. This metastatic activity was observed with i.v. and with i.p. peptide injections, regardless of tumor cell or of peptide-injection times. In vitro, the AG-73 peptide enhances tumor cell adhesion, migration, invasion, and gelatinase production, and blocks laminin-1-mediated cell migration. AG-73 was found to significantly inhibit cell adhesion to a proteolytic laminin-1 fragment, E3, containing the AG-73 sequence. Cell attachment to AG-73, the E3 fragment, and laminin-1 involved cation-dependent receptors. We report that a laminin peptide has the novel and unexpected activity of causing B16F10 melanoma cells, a lung selected cell line, to metastasize to the liver. The minimal active sequence of AG-73, LQVQLSIR, could be one of the most important biologically active sites of laminin-1, especially in promotion of the malignant phenotype. Activation of the malignant phenotype by this peptide provides a significant new model for understanding metastatic mechanisms.
我们之前从层粘连蛋白α1链的球状结构域筛选了重叠的合成肽，以确定细胞附着的活性位点。我们在此报告，其中一种活性细胞黏附肽AG-73（精氨酸-赖氨酸-精氨酸-亮氨酸-谷氨酰胺-缬氨酸-谷氨酰胺-亮氨酸-丝氨酸-异亮氨酸-精氨酸-苏氨酸；RKRLQVQLSIRT）可使B16F10小鼠黑色素瘤细胞转移至肝脏，而肝脏并非这些细胞通常定植的部位。在免疫缺陷的米色/裸鼠/xid小鼠以及C57Bl/6小鼠中，使用该肽后观察到肝脏转移和肺部定植增加。静脉注射和腹腔注射该肽均观察到这种转移活性，与肿瘤细胞或肽注射时间无关。在体外，AG-73肽增强肿瘤细胞的黏附、迁移、侵袭和明胶酶产生，并阻断层粘连蛋白-1介导的细胞迁移。发现AG-73可显著抑制细胞与含有AG-73序列的蛋白水解层粘连蛋白-1片段E3的黏附。细胞与AG-73、E3片段和层粘连蛋白-1的附着涉及阳离子依赖性受体。我们报告，一种层粘连蛋白肽具有使B16F10黑色素瘤细胞（一种肺源性细胞系）转移至肝脏的新颖且意想不到的活性。AG-73的最小活性序列LQVQLSIR可能是层粘连蛋白-1最重要的生物活性位点之一，尤其是在促进恶性表型方面。该肽激活恶性表型为理解转移机制提供了一个重要的新模型。
