TIMP－1基因转染对人肺巨细胞癌细胞系生物学行为的影响

利用基因重组技术构建了一个含有全长人ＴＩＭＰ－１ｃＤＮＡ的真核表达重组体。重组质粒通过脂质体法导入高转移入肺巨细胞癌细胞系（ＰＧ细胞）。随机挑选５个Ｇ４１８抗性克隆，并对其中的两个克隆ＰＧ－Ｔ２和ＰＧＴ４进行了深入的研究。Ｎｏｒｔｈｅｒｎ印迹表明，这两个克隆具有较高的ＴＩＭＰ－１ＲＮＡ表达，其表达水平明显高于ＰＧ细胞和空载体转染对照细胞ＰＧ－ＭＶ。ＰＧ－Ｔ２和ＰＧ－Ｔ４克隆细胞显示出很高的ＴＩＭＰ－１蛋白活性，相同条件下ＰＧ和ＰＧ－ＭＶ未能显示出具有ＴＩＭＰ－１蛋白活性。此外，与其母系ＰＧ细胞及空载体转染对照细胞ＰＧ－ＭＶ相比，ＴＩＭＰ－１转染细胞的增殖速度和侵袭能力明显下降，其在软琼脂上形成克隆和在裸鼠体内成瘤的能力丧失。提示ＰＧ细胞中ＴＩＭＰ－１基因的特异性上调不仅能抑制其侵袭能力，而且对其增殖和成瘤产生抑制作用。

Effects of TIMP-1 cDNA transfection on biologicalbehaviors of PG cells

recombinant plasmid, which contains a fulllenth cDNA of human tissue inhibitor ofmetalloproteinases-l (TIMP-l), was constructed byusing gene recombinant technique, and introduced in-to a highly metastatic human giant eell carcinoma(PG) by lipofectin technique. Two of the transfectants,PG-T2 and PG-T4, were studied thoroughly. Northern blot showed an increased level of TIMP-1mRNA in PG-T2 and PG-T4, compared with PGand PG-MV1 (vector-transfected control). The twotransfectants also exhibited higher TIMP-1 proteinactivities. Moreover, they showed significant reductionin their proliferation rate and invasive abilities. Theabilities of forming colonies in soft agar andtumorigenecity in athymic nude mice were abrogatedin PG-T2 and PG-T4. The preliminary results sug-gest that a specific upregulation of TIMP-l expres-sion in metastatic cells could not only supress theirinvasive and metastatic phenotype, but also inhibittheir proliferation and tumorigenecity.