呼肠孤病毒诱导乳腺癌微球体细胞凋亡

Reovirus induces apoptosis of breast cancer mammosphere cells

目的:探讨呼肠孤病毒对乳腺癌微球体细胞凋亡的影响。方法:以干细胞培养液培养乳腺癌细胞MCF-7和BT474,形成微球体,分别用呼肠孤病毒和表柔比星处理微球体,FCM检测MCF-7、BT474微球体细胞中CD44+CD24-/low细胞的比例,TUNEL法检测微球体细胞的凋亡,Western blotting检测MCF-7细胞及其微球体细胞中Ras的表达。结果:呼肠孤病毒对乳腺癌MCF-7和BT474微球体细胞的感染率显著高于亲本细胞(均P<0.05)。表柔比星作用下MCF-7和BT474微球体细胞中CD44+CD24-/low细胞比例明显升高[(8.1±0.4)%vs(18.0±4.5)%,P<0.01;(0.6±0.2)%vs(0.9±0.13)%,P<0.05]。呼肠孤病毒感染后MCF-7和BT474微球体细胞中CD44+CD24-/low细胞比例明显下降[(8.1±0.4)%vs(0.8±0.2)%,(0.6±0.2)%vs(0.2±0.1)%;均P<0.05]。MCF-7和BT474微球体细胞在呼肠孤病毒感染后凋亡率明显增加[(1.90±0.21)%vs(5.0±1.4)%,P<0.05;(0.20±0.1)%vs(1.0±0.16)%,P<0.05]。MCF-7细胞及其微球体细胞均高表达Ras,且两者水平相似。结论:与表柔比星相比,呼肠弧病毒对乳腺癌微球体细胞的抑制作用明显,还可明显诱导乳腺癌微球体细胞凋亡。

Objective ： To investigate the effect of reovirus on apoptosis of breast cancer mammosphere cells. Methods ： MCF-7 and BT474 cells were cultured in stem cell culture medium to generate mammospheres. Then the mammospheres were infected by reovirus or treated with epirubicin, The proportion CD44 ± CD24 -/low cells in the mammosphere cells from MCF-7 and BT474 cells was detected by flow cytometry （FCM） ; the apoptosis of mammosphere cells was detected by TUNEL; and the expression of Ras in MCF-7 cells and the mammosphere cells was examined by Western blotting. Results： The infection rates of reovirus on MCF-7 and BT474 mammosphere cells were significantly higher than those on MCF-7 and BT474 cells （ all P 〈 0.05 ）. The proportions of CD44 ~ CD24 -/low cells in the mammosphere cells from MCF-7 and BT474 cells after treatment with epirubicin were improved greatly （ [ 8.1 ± 0.4 ] % vs [ 18.0 ± 4.5 ] %, P 〈 0.01 ; [ 0. 6 ±0. 2 ] % vs [ 0.9 ± 0.13 ] %, P 〈 0.05 ）, while the proportions of CD44 ± CD24 -/low cells in the mammosphere cells after treatment with reovirus were decreased apparently （ [ 8.1 ± 0.4 ] % vs [ 0.8 ± 0.2 ] %, P 〈 0.05 ; [ 0.6 ± 0.2 ] % vs [ 0.2 ± 0.1 ] % , P 〈 0.05 ）. The apoptosis rates of the mammospheres cells from MCF-7 and BT474 cells rose up from （1.9±0.21）% to （5 ±1.4）% （P〈0.05） and from （0.2±0.1）% to （1.0±0.16）% （P〈0.05） afterreovirus treatment. Ras levels in MCF-7 cells and the mammosphere cells were almost same high. Conclusion： Compared with that of epirubiein, reovirus has a higher inhibitory effect on breast cancer mammosphere cells, while reovirus distinctively induces apoptosis of mammosphere cells.