小鼠早期胚胎与肿瘤细胞共培养下的相互作用

The Co-cultural Interaction of Mice's Early Embryo and Tumor Cells in Vitro

目的建立小鼠早期胚胎与肿瘤细胞体外共培养模型,以观察共同微环境中胚胎发育情况及肿瘤细胞生物学行为,并探讨两者间的相互作用。方法获取小鼠2-细胞胚胎,与小鼠肿瘤细胞株体外共培养,观察胚胎的体外发育状况,并观测4-细胞胚胎、桑葚胚、囊胚的形成率。采用插入式细胞培养皿共培养,噻唑蓝法检测肿瘤细胞的增殖活力及流式细胞术检测其凋亡率;通过碘化丙啶染色及免疫组织化学技术,进一步分析肿瘤细胞与早期胚胎共培养时的相互作用。结果体外共培养下2-细胞胚胎可存活并继续发育,且4-细胞胚胎、桑葚胚、囊胚形成率较阴性及阳性对照组均有显著提高(P<0.05);插入式共培养24、48、72 h,肿瘤细胞的增殖活力和凋亡率较对照组差异均无统计学意义(P>0.05);胚胎滋养层周围可形成"无瘤圈",其周围肿瘤细胞增殖细胞核抗原及B细胞淋巴瘤/白血病-2的表达水平较其他区域未见差异。结论早期胚胎与肿瘤细胞共培养可显著提高2-细胞胚胎的体外发育效率,局部共培养并未对肿瘤细胞的增殖、凋亡产生影响。

Objective To establish the co-culture model of mice＇s early embryo and tumor cells in vitro to observe the embryonic development and biologic behavior of tumor cells in the same microenvironment and discuss their interaction. Methods We acquired 2-cell embryos from mice, and then co-cultured them with tumor cell lines of mice in vitro. We observed the development of embryos in vitro and the rates of 4-cell embryos, morula and blastocyst formation. The transwell chamber was used for culture. Methylthiazolyldiphenyl-tetrazolium method was used to test the proliferative activity of tumor cells, while the flow cytometry was used to test its apoptosis. The interaction of co-cultured embryos and tumor cells was analyzed by propidium iodide staining and immunohistochemical technique. Results The co-cultured 2-cell embryos could continue surviving and developing. The rates of 4-cell embryos, morula and blastocyst formation increased significantly in the co-cultured group （P 〈 0.05）. There was no significant difference in the proliferative activity and apoptosis of tumor cells between the co-cultured group and the control group （P 〉 0.05）. Tumor-free ring formed between the trophoblast and tumor cells. We could observe tumor cells stacked around the tumor-free ring. However, no difference in expression of proliferating cell nuclear antigen and B-cell lyrnphoma leukemia-2 was observed in tumor cells stacking around the tumor-free ring compared with those elsewhere. Conclusions The development of 2-cell embryos is enhanced in the co-culture model. The proliferative activity and apoptosis of tumor cells are not affected in this model. A tumor-free ring can form between trophoblast and tumor cells. However, the proliferative activity of tumor cells is not affected by this ring.