KAI1基因对乳腺癌细胞体外增殖的抑制作用

目的研究KAI1基因对乳腺癌细胞体外增殖的抑制作用。方法应用脂质体法将pCMV-KAI1质粒转染人高转移性人乳腺癌细胞株MDA-MB-231中,免疫印迹方法检测蛋白表达;利用四甲基偶氮唑盐(MTT)法、平板克隆形成实验、体外黏附及侵袭力实验判断细胞增殖能力及黏附、侵袭力的变化。流式细胞术检测细胞生长周期的变化。结果获得了稳定表达KAI1基因的MDA- MB-231乳腺癌细胞克隆。MTT法显示,转染KAI1基因组的集落形成率(25.33%±2.36%)较转染前(43.17%±2.75%)明显降低(P<0.05)。体外黏附及侵袭力实验表明,转染组的细胞黏附侵袭能力低于未转染组和转染空载体组(P<0.05)。流式细胞术显示,转染KAI1后,G_0/G_1期细胞数量增高,从36.78%±0.61%升高至64.00%±7.56%;G_2/M期数量降低,由17.88%±0.76%降至7.63%±0.60%,差异有统计学意义。结论KAI1基因可以抑制乳腺癌细胞的增殖黏附和侵袭能力,并可能通过调节细胞周期来影响细胞的增殖。

Inhibitory effect of KAI1 gene on breast cancer cell growth in vitro

OBJECTIVE: To explore the inhibitory effect of KAI1 gene on breast cancer cell growth in vitro. METHODS: Highly metastatic human breast cancer cell line MDA-MB-231 was transfected with pCMV-KAI1 or mock transfected plasmid pCMV with lipofectamine. Western blot was used to determine the expression of target protein of KAI1. The proliferative ability of cells was tested by MTT assay and colony-forming test. The cell cycle pattern was assayed by flow cytometry. The metastatic ability was investigated by cell adhesion and invasion assays. RESULTS: A stable cell clone transfected with KAI1 gene was obtained and over-expression of KAI1 protein was observed. There was a significant decline in cell proliferative ability of pCMV-KAI1 transfected MDA-MB-231 cells in comparison with the mock-transfected ones and non-transfected ones, revealed by MTT assay and colony-forming test (P < 0.05). The ability of adherence and invasion of pCMV-KAI1 transfected cells was significantly reduced in comparison with the other two groups (P < 0.05). Also, flow cytometry analysis revealed that in KAI1 transfected cell group the number of cells in G0/G1 phase increased markedly from 36.78% +/- 0.61% to 64.00% +/- 7.56%, while the number of cells in G2/M phase decreased from 17.88% +/- 0.76% to 7.63% +/- 0.60%, comparing with the non-transfected ones. CONCLUSION: KAI1 gene suppresses the invasive ability of human breast cancer cells in vitro and may inhibit the proliferative ability by changing the cell cycle pattern.