番茄红素对乳腺癌细胞MCF-7和MDA-MB-231增殖的影响

目的 观察番茄红素对体外培养的雌激素受体阳性(ER )乳腺癌细胞MCF-7和雌激素受体阴性(ER-)乳腺癌细胞MDA-MB-231的存活率、细胞周期及凋亡的影响.方法 采用MTT法和H3-TdR 掺入法观察番茄红素对两种细胞增殖的影响;流式细胞仪观察同步化的细胞经番茄红素作用后细胞周期及凋亡的变化.结果 番茄红素抑制MCF-7、MDA-MB-231细胞的增殖和DNA合成,具有剂量效应关系,随着时间延长,抑制作用增强,最大抑制率分别为52.6%、61.9%.流式细胞仪结果显示,番茄红素作用24 h后,MCF-7、MDA-MB-231细胞周期各相发生变化,G0/G1期细胞增多,而S期和G2/M期细胞减少,同时可诱发MDA-MB-231细胞凋亡.结论 番茄红素通过阻滞MCF-7细胞于G1期而抑制该细胞的增殖,而对MDA-MB-231细胞增殖的抑制除可通过阻滞细胞周期进程外,还与诱导凋亡有关.

Effect of Lycopene on the Proliferation of MCF-7 and MDA-MB-231 Cells

Objective To test the effect of lycopene on the proliferation and apoptosis of the estrogen receptor(ER)-positive MCF-7 and ER -negative MDA-MB-231 human breast cancer cell lines. Methods The cell proliferation was analyzed by the MTT and the H3-TdR incorporation. The effect of lycopene on the cell cycle and apoptosis of the synchronized cells was observed through flow cytometry. Results Lycopene inhibited the growth and DNA synthesis of both ER-positive MCF-7 and ER-negative MDA-MB-231 cells in a dose-dependent pattern. The maximum inhibition effect appeared after 4 days of exposure to lycopene, with an inhibition rate of 52.6% and 61.9% for the MCF-7 and MDA-MB-231 cells respectively. The flow cytometry analysis found more cells in the G0/G1 phase and less cells in the S and G2/M phase after 24 hours of exposure to lycopene. Lycopene induced apoptosis for the MDA-MB-231 cells, but not for the MCF-7 cells. Conclusion Lycopene inhibits the growth of ER-positive MCF-7 cells through the inhibition of the cell cycle progression. The inhibition of ER-negative MDA-MB-231 cells by lycopene is associated not only with the G1 phase cell cycle-arrest but also the induction of apoptosis.