抑制人肺腺癌细胞MCT1基因的表达对其增殖、凋亡的影响

Effect of Inhibiting the Expression of the First Subtype of the Monocarboxy-late Transporter ( MCT1) Gene on Proliferation and Apoptosis in Human Lung Adenocarcinoma Cells

目的:研究抑制单羧酸转运蛋白第1亚型(MCT1)基因的表达对肿瘤细胞增殖、凋亡的影响。方法:用电穿孔法将MCT1反义基因表达载体转染进人肺腺癌A549细胞中,以抑制MCT1基因表达。经G418筛选阳性克隆。用PCR,RT-PCR方法鉴定MCT1反义基因与A549基因组的整合;用分光光度法和生物发光法分别测定细胞内pH(intracellular pH,pHi)、乳酸含量和ATP含量。用原位凋亡试剂盒测定细胞凋亡情况,并接种转染MCT1反义基因的细胞和A549细胞于裸鼠皮下,观察移植瘤的生长。结果:与A549细胞比较,转染MCT1反义基因的细胞pHi降低(P<0.05)、乳酸显著升高(P<0.001),ATP含量明显降低(P<0.05)。转染MCT1反义基因的细胞凋亡率明显高于A549细胞(P<0.01)。接种转染MCT1反义基因的细胞移植瘤明显比接种A549细胞的轻且小(P<0.001)。结论:MCT1基因对肿瘤细胞增殖凋亡具有重要的调节作用。

Objective: To study the effect of inhibiting the expreesion of the first subtype of the monocarboxylate trans-porter( MCTl) gene on proliferation and apoptosis in tumor cells. Methods: MCTl antisense gene expression vector was introduced into A549 cells with electroporation to inhibit the expression of MCTl gene. The positive colonies were selected by G418. The integration of MCTl antisense gene and A549 genomic DNA was confirmed by PCR and RT-PCR technique. The pHi, lactate content and ATP content were detected with spectrophotometry and bioluminescence method respectively. The conditions of cell apoptosis were measured with in situ apoptosis assay kit. And cells transfected MCTl antisense gene and A549 cells were inoculated in nude mouse subcutaneous to observe the growth of transplantation tumor. Results: Compared with A549 cells, the pHi of cells transfected MCTl antisense gene was remarkably decreased ( P < 0. 05) , and lactate content was remarkably increased (P <0. 001) , ATP content was remarkably decreased (P <0. 05) . Apoptosis rate of cells transfected MCTl antisense gene was remarkly higher than A549 cells (P <0. 01 ). And the nude mouse transplantation tumors inoculated cells transfected MCTl antisense gene were significantly lighter and smaller than that ones inoculated A549 cells ( P < 0.001) . Conclusion: MCTl gene plays an important role in proliferation and apoptosis of tumor cells.