放线菌素D在cFLIP抑制大肠癌细胞凋亡中的作用

The effect of actinomycin D on the inhibition of apoptosis by cFLIP in coiorectal cancer cell

目的探讨放线菌素D(Act D)在下调cFLIP表达水平增加大肠癌细胞凋亡中的作用。方法应用流式细胞仪(FCM)技术检测ActD预处理的人大肠癌细胞(SW620)凋亡水平、Fas受体及cFLIP蛋白表达的变化情况,并观察在ActD存在时,cFLIP蛋白对大肠癌细胞凋亡的影响。结果10μg/L ActD作用于SW620细胞后,cFLIP蛋白的表达水平随着作用时间的延长而降低。ActD作用24h后,cFLIP_L表达强度由94．4%下降到71．8%,此时1mg/L的抗Fas抗体诱导SW620细胞凋亡率达33．7%,但Act D本身对大肠癌细胞的凋亡及Fas受体表达无明显影响(P＞0．05)。结论低浓度放线菌素D可明显下调SW620细胞中cFLIP蛋白的表达水平并显著增加大肠癌细胞的凋亡率,Act D有可能成为靶向调节cFLIP蛋白在大肠癌细胞中表达的理想药物。

Objective To study the modulatory effect of Actinomycin D （Act D） on in down-regulating cFLIP expression and promoting the apoptosis of colon cancer cell. Methods Flow cytometry scan（FACS） was employed to detectFas and cFLIPL expression and the apoptosis of SW620 ceU line pretreated with Act D. The effect of cFLIPL on apoptosis in SW620 cell line pretreated with Act D was also examined by FACS. Results After the SW620 ceUs were incubated with Act D （10 μg/L） for 24 h, the cFLIPL expression was decreased obviously from 94.4 % to 71.8 %. At the same time, the apoptosis rate of 33.7% was observed in SW620 ceU line induced by anti-Fas （1 mg/L）.But Act D itself had no effect on the expression of Fas and the apoptosis of colon cancer cells. Conclusion Low dose Act D could significantly down-regulate the expression of cFLIP protein in SW620 cells and obviously increase the apoptosis rate of colon cancer ceils. Act D may be an ideal drug for regulating the expression of cFLIP in colon cancer cells.