人白细胞介素1β通过caspase途径诱导人黑色素瘤A375-S2细胞凋亡

目的:对interleukin-1β(IL-1β)诱导人黑色素瘤A375-S2细胞凋亡的信号转导途径进行研究。方法:使用倒置显微镜观察细胞形态学变化。通过MTT法测定IL-1β对A375-S2细胞的抑制作用以及细胞内半胱氨酸蛋白酶(caspases)与这种作用的关系。利用乳酸脱氢酶(LDH)测定法对IL-1β作用后细胞的损伤情况进行分析。琼脂糖凝胶电泳法检测IL-1β对细胞DNA降解的影响。结果: IL-1β对A375-S2细胞的抑制作用呈剂量和时间依赖性,在10^-9mol/L作用72 h时达到90%以上。caspase-1、-3、-8、-9和caspase-10的抑制剂能够部分抑制IL-1β早期诱导的细胞凋亡。 LDH活力测定显示,在IL-1β诱导的细胞死亡过程中,凋亡占主导地位,并呈现剂量和时间依赖性 。细胞经过10^-11mol/L IL-1β处理72 h后,出现凋亡典型的DNA梯状条带,与上述结果一致。 结论: IL-1β能够诱导人黑色素瘤A375-S2细胞凋亡,这种作用可能依赖于激活一类介导凋亡的caspase家族蛋白酶。

Human interleukin- 1βinduces A375- S2 human melanoma apoptosis through caspase pathway

AIM: To study the molecular biological mechanism and signal transduction pathway of interleukin-1β (IL-1β)-induced apoptosis in A375-S2 melanoma cells. METHODS: Photomicrocropy showed typical apoptotic changes. The cytotoxic effect of IL-1β in vitro and influences of caspases in this effect were measured by MTT assay. The cytotoxicity of cells was assessed by LDH-based assay. Degradation of DNA was detected by agarose gel electrophoresis. RESULTS: The inhibitory effect of IL-1β on A375-S2 cell growth was in a dose and time-dependent manner, and cell death rate reached more than 90% at 72 h after treatment with 10^-9mol/L IL-1β. The inhibitors of caspase-family, -1, -3, -8, -9, and -10, partially blocked cell death at early stage. LDH assay showed that major IL-1β-induced cell death was apoptosis, and in a dose and time-dependent manner. Typical apoptotic DNA ladder was observed in agarose gel electrophoresis. CONCLUSION: IL-1β induced apoptosis in melanoma A375-S2 cells by activating caspase pathway.