title: Glycine-extended gastrin induces matrix metalloproteinase-1- and -3-mediated invasion of human colon cancer cells through type I collagen gel and Matrigel.
abstract: The effects of glycine-extended gastrin (G-Gly) on the invasion by colon cancer cells through stromal extracellular matrix and the role of metalloproteinases (MMPs) in this invasion were investigated. We found that 10(-9)-10(-6) M G-Gly significantly increased the invasiveness of 2 human colon cancer cell lines, LoVo and HT-29, both expressing the G-Gly-specific binding site but little gastrin/CCK-B receptor (gastrin receptor). LoVo cells expressed MMP-1, -2, -3 and -9. An amount of 10(-7) M G-Gly enhanced collagenase MMP-1 expression. Overexpression of enhanced green fluorescent protein (EGFP)-fused MMP-1 in LoVo cells, by cDNA transfection, enhanced invasiveness through type I collagen gel. Immunofluorescence study revealed that G-Gly increased the number of cytoplasmic vesicles containing MMP-1, some vesicles being released from the cells. The MMP-1 vesicles contained one of the ubiquitous coat proteins, Golgi-localized, gamma-adaptin ear-containing, ARF-binding proteins-2 (GGA-2). MMP-1 also colocalized with CD147 (EMMPRIN, an extracellular matrix metalloproteinase inducer in adjacent stromal cells). It was suggested that G-Gly increased the number of vesicles containing MMP-1 and that MMP-1 interacted with CD147 to increase invasion. G-Gly significantly enhanced the production of MMP-3, an activator of MMP-1 and -9, as well as gelatinase MMP-9 activity. The G-Gly-mediated MMP-9 increase was inhibited by treatment with anti-MMP-3 IgG and MMP-3 siRNA. Furthermore, G-Gly increased the proMMP-2 level, although no activated MMP-2 was found in conditioned medium in either the presence or the absence of G-Gly. By contrast, gastrin (10(-7) M) had no effect on the levels of these MMPs or the invasiveness of colon cancer cells in type I collagen gel and Matrigel. These effects of G-Gly on the activity and expression of MMPs and the invasiveness of colon cancer cells were inhibited by treating the cells with a broad-spectrum metalloproteinase inhibitor (CGS27023A) and nonselective gastrin/CCK receptor antagonists (proglumide and benzotript). But a gastrin/CCK-B receptor antagonist (YM022) did not inhibit the increased invasion by G-Gly. Together, these results demonstrate that G-Gly renders colon cancer cells more invasive by increasing MMP-1 and MMP-3 expressions via the putative G-Gly receptor and would thus be a good molecular target in a clinical setting.
authors.affiliation: Department of Pathology, Research Institute, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan. baba-mi@mc.pref.osaka.jp
authors.forename: Miyako
authors.initials: M
authors.lastname: Baba
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Itoh
authors.forename: Masaharu
authors.initials: M
authors.lastname: Tatsuta
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry; D003094:Collagen / Q000737:chemistry; D024042:Collagen Type I; D003110:Colonic Neoplasms / Q000473:pathology*; D018076:DNA, Complementary; D004338:Drug Combinations; D005755:Gastrins / Q000494:pharmacology*; D005782:Gels; D006801:Humans; D007797:Laminin / Q000737:chemistry; D020781:Matrix Metalloproteinase 1 / Q000494:pharmacology*; D019278:Matrix Metalloproteinase 3 / Q000494:pharmacology*; D009361:Neoplasm Invasiveness / Q000503:physiopathology*; D011509:Proteoglycans / Q000737:chemistry; D014162:Transfection; D014407:Tumor Cells, Cultured
chemical_list: D001672:Biocompatible Materials; D024042:Collagen Type I; D018076:DNA, Complementary; D004338:Drug Combinations; D005755:Gastrins; D005782:Gels; D007797:Laminin; D011509:Proteoglycans; C058638:tyrosyl-glycyl-tryptophyl-methionyl-aspartyl-phenylalanyl-glycine; C059485:matrigel; D003094:Collagen; D019278:Matrix Metalloproteinase 3; D020781:Matrix Metalloproteinase 1