中文摘要：

目的：研究黑色素瘤分化相关基因-7（melanoma differentiation associated gene 7,MDA-7）/IL-24对Burkitt淋巴瘤细胞的促分化作用并探讨其作用机制。方法：构建稳定过表达MDA-7/IL-24的人Burkitt淋巴瘤Raji和Daudi细胞株,MTS法检测稳定转染MDA-7/IL-24对Raji和Daudi细胞活力的影响;Transwell小室实验检测转染MDA-7/IL-24对Raji和Daudi细胞侵袭和迁移能力的影响;流式细胞术检测细胞凋亡水平及免疫表型;Western blotting技术检测转染MDA-7/IL-24对Raji和Daudi细胞表达分化相关蛋白Myb、BLIMP1及BCL-6的影响;建立裸鼠Raji细胞移植瘤模型,检测在体内环境中稳定转染MDA-7/IL-24对Raji细胞生物活性的影响。结果：过表达MDA-7/IL-24的Raji和Daudi细胞其增殖（P〈0.05）、侵袭（P〈0.01）及迁移（P〈0.01）能力均明显下降,但凋亡细胞无明显增加（P〉0.05）,表达CD45及CD138的水平均明显增加（P〈0.01）,而表达CD10的水平明显下降（P〈0.01）。过表达MDA-7/IL-24的Raji和Daudi细胞表达BLIMP1的水平明显增加（P〈0.01）,而表达Myb及BCL-6的水平均明显减低（P〈0.01）。MDA-7/IL-24过表达组裸鼠模型Raji细胞移植瘤质量明显低于对照组[（1.23±0.21）vs（1.96±0.24）g,P〈0.01]。结论：转染MDA-7/IL-24可能通过诱导分化作用抑制Burkitt淋巴瘤细胞的生物活性。

英文摘要：

Objective： To investigate the differentiation-inducing effect of melanoma differentiation associated gene 7（MDA-7）/IL-24 on human Burkitt lymphoma cells, as well as its underlying mechanism. Methods： Human Burkitt lymphoma cell lines（Raji and Daudi） that stably over-expressing MDA-7/IL-24 were constructed. The effect of MDA-7/IL-24 transfection on cell viability of Raji and Daudi cells was assayed by MTS method; the effect on migration and invasion of Raji and Daudi cells were analyzed by Transwell assay. The apoptosis and immunophenotypes of Raji and Daudi cells with MDA-7/IL-24 over-expression were analyzed by flow cytometry. Meanwhile, the expressions of differentiation related proteins（Myb, BLIMP1 and BCL-6） were analyzed by Western blotting. Raji cell xenograft model was established on nude mice to analyze the effect of MDA-7/IL-24 on the bioactivity of Raji cells in vivo. Results： The cell viability, migration and invasion ability of Raji and Daudi cell lines that transfected with MDA-7/IL-24 were obviously decreased（all P〈0.01）, however, the apoptosis cells were not increased（P〈0.05）. The expressions of CD45 and CD138 were elevated（P〈0.01） while the expression of CD10 was decreased（P〈0.01） in Raji and Daudi cells overexpressing MDA-7/IL-24. MDA-7/IL-24 over-expression in Raji and Daudi cells significantly increased the expression of BLIMP1（P〈0.01）, but decreased the expression of Myb and BCL-6（P〈0.01）. The tumor mass of nude mice was significantly decreased after the treatment of MDA-7/IL-24（[1.23 ±0.21] vs [1.96 ± 0.24]g, P〈0.01）. Conclusion： Transfection with MDA-7/IL-24 inhibited the bio-actively of Burkitt lymphoma cells, which might be accomplished by inducing differentiation.