Zhuang Zhi-Gang, Di Gen-Hong, Hou Yi-Feng, Liu Gang, Luo Jian-Min, Shen Zhen-Zhou, Shao Zhi-Min
Department of Breast Surgery, Shanghai First Maternal and Child Hospital, Shanghai 200040, China.
Zhonghua Yi Xue Za Zhi. 2007 Jan 9;87(2):81-4.
To investigate the relationship between LKB1 gene and invasion of breast cancer cells.
Human breast cancer cells of the line MDA-MB-435 were cultured and transfected with plasmids with or without LKB1 gene. The clone of the transfected MDA-MB-435 cells with high expression of LKB1 was called MDA-MB-435/LKB1 (H), and that with low expression of LKB1 was called MDA-MB-435/LKB1 (L). The MDA-MB-435 cells transfected with blank vector was called MDA-MB-435/vec. MDA-MB-435 cells without transfection were used as controls. RT-PCR was used to detect the mRNA expression of the invasion-related factors of breast cancer: matrix metalloproteinase (MMP)-2, MMP-9, vascular endothelial growth factor (VEGF), and basic fibroblast growth factor (bFGF), and Western blotting was used to detect the protein expression of these factors. Gelatin zymography was used to expression of the secretive MMP-2 and MMP-9. Transwell test was used to examine the membrane penetration of the different MDA-MB-435 cells.
The invasion rate was (47.6 +/- 1.3)% in the MDA-MB-435 cells, (45.6 +/- 1.2)% in the MDA-MB-435/vec cells, both significantly higher than those of the MDA-MB-435/LKB1 (H) and MDA-MB-435/LKB1 (L) cells [(18.1 +/- 1.0)% and (22.4 +/- 1.8)% respectively, all P < 0.01], with significant difference between the latter 2 groups (P < 0.05). The mRNA expression and protein expression of MMP-2, MMP-9, VEGF, and b-FGF were all significantly lower in the MDA-MB-435/LKB1 cells. Gelatin zymography showed that the secretive MMP-2 and MMP-9 were expressed at the protein level significantly lower in the MDA-MB-435/LKB1 cells.
LKB1 gene inhibits the invasion of breast cancer cells.
探讨LKB1基因与乳腺癌细胞侵袭之间的关系。
培养人MDA-MB-435乳腺癌细胞系，用含或不含LKB1基因的质粒进行转染。转染后LKB1高表达的MDA-MB-435细胞克隆称为MDA-MB-435/LKB1（H），LKB1低表达的称为MDA-MB-435/LKB1（L）。转染空载体的MDA-MB-435细胞称为MDA-MB-435/vec。未转染的MDA-MB-435细胞用作对照。采用逆转录-聚合酶链反应（RT-PCR）检测乳腺癌侵袭相关因子基质金属蛋白酶（MMP）-2、MMP-9、血管内皮生长因子（VEGF）和碱性成纤维细胞生长因子（bFGF）的mRNA表达，采用蛋白质印迹法检测这些因子的蛋白表达。用明胶酶谱法检测分泌型MMP-2和MMP-9的表达。采用Transwell试验检测不同MDA-MB-435细胞的穿膜能力。
MDA-MB-435细胞的侵袭率为（47.6±1.3）%，MDA-MB-435/vec细胞的侵袭率为（45.6±1.2）%，两者均显著高于MDA-MB-435/LKB1（H）和MDA-MB-435/LKB1（L）细胞[分别为（18.1±1.0）%和（22.4±1.8）%，均P<0.01]，后两组之间差异有统计学意义（P<0.05）。MDA-MB-435/LKB1细胞中MMP-2、MMP-9、VEGF和b-FGF的mRNA表达及蛋白表达均显著降低。明胶酶谱法显示，MDA-MB-435/LKB1细胞中分泌型MMP-2和MMP-9的蛋白表达水平显著降低。
LKB1基因抑制乳腺癌细胞的侵袭。
