Togawa D, Koshino T, Saito T, Takagi T, Machida J
Department of Orthopaedic Surgery, Yokohama City University School of Medicine, Japan.
Cancer Lett. 1999 Nov 1;146(1):25-33. doi: 10.1016/s0304-3835(99)00214-1.
The promoting effects of matrix metalloproteinase-2 (MMP-2) on lung metastasis of human fibrosarcoma cells (HT1080) were studied using nude mice. The fourth generation of HT1080 was established by consecutive clonal selection of metastatic lung nodules formed by intravenous transplantation. MMP-2 and MMP-9 in the culture supernatants of the first and fourth generation cells were analyzed by gelatin zymography and Western blotting, and quantified by scanning densitometry. In gelatin zymograms, mean ratios of values for the 59-kDa band (the active form of MMP-2) to those for the 72-kDa band (the inactive form of MMP-2) for optical density; area, and volume measured by densitometry were 1.44 +/- 0.12, 0.93 +/- 0.05, and 1.27 +/- 0.20, respectively, in the culture supernatant of fourth generation cells isolated from metastatic lung nodules. These values were significantly (P < 0.01) higher than those of first generation cells (0.70 +/- 0.04, 0.48 +/- 0.01, and 0.57 +/- 0.42). Three weeks after intravenous transplantation of HT1080 cells into nude mice, the incidence of lung metastasis and mean number and diameter of metastatic nodules formed by injection of first generation cells were 20% (2 of 10 mice), 2.9 +/- 0.2 and 2.0 +/- 0.2 mm, respectively; while they were 100%, 99.8 +/- 7.2 and 4.3 +/- 0.3 mm following injection of fourth generation cells. These findings suggest that the active MMP-2 produced by human fibrosarcoma cells is important for the cells to form lung metastatic lesions in nude mice.
利用裸鼠研究了基质金属蛋白酶-2（MMP-2）对人纤维肉瘤细胞（HT1080）肺转移的促进作用。通过对静脉移植形成的转移性肺结节进行连续克隆选择，建立了HT1080的第四代细胞。采用明胶酶谱法和蛋白质免疫印迹法分析第一代和第四代细胞培养上清液中的MMP-2和MMP-9，并通过扫描光密度法进行定量。在明胶酶谱中，通过光密度法测量的、转移性肺结节分离出的第四代细胞培养上清液中59 kDa条带（MMP-2的活性形式）与72 kDa条带（MMP-2的无活性形式）的光密度、面积和体积的平均比值分别为1.44±0.12、0.93±0.05和1.27±0.20。这些值显著高于第一代细胞（0.70±0.04、0.48±0.01和0.57±0.42）（P<0.01）。将HT1080细胞静脉注射到裸鼠体内三周后，注射第一代细胞形成肺转移的发生率、转移结节的平均数量和直径分别为20%（10只小鼠中有2只）、2.9±0.2和2.0±0.2mm；而注射第四代细胞后，这些指标分别为100%、99.8±7.2和4.3±0.3mm。这些结果表明，人纤维肉瘤细胞产生的活性MMP-2对其在裸鼠体内形成肺转移瘤很重要。
