DNA片段原位末端标记法分析X刀治疗大鼠C6胶质瘤诱发的细胞凋亡

In situ end labeling detects of DNA strand breaks associated with apoptosis in X knife treating rat C6 glioma

探讨用ＤＮＡ片段原位末端标记技术研究Ｘ刀治疗大鼠Ｃ６胶质瘤诱发的细胞凋亡。对Ｘ刀治疗的各组动物肿瘤组织发生的细胞凋亡采用经典的ＤＮＡ琼脂糖凝胶电泳和ＤＮＡ原位末端标记法进行了研究。经ＤＮＡ片段原位末端标记法研究发现，Ｘ刀１５Ｇｙ、２０及３０Ｇｙ治疗后在１周内诱发出明显的细胞凋亡，此时的细胞凋亡数与对照组及４０Ｇｙ组相比差异有极显著意义（Ｐ＜０．０１）。这一结果与ＤＮＡ琼脂糖凝胶电泳所得结果完全吻合。另外在４０Ｇｙ组及其它剂量治疗各组均发现有坏死成份，尤以前者明显。利用该法证实Ｘ刀治疗大鼠Ｃ６胶质瘤后诱发出明显细胞凋亡的同时还致细胞坏死，这种致坏死效应随剂量增加渐趋明显。

To investigate apoptosis in X knife treating rat C6 glioma by way of a novel technique, in situ end labeling. We scored apoptotic cell which was detected by this technique as positive nuclei by microscopic examination of paraffin sections made from the tumor specimens under the assistance of computer image handling and SAS statistical systems and observed as a classical “Ladder pattern” of oligonucleosome sized fragments character by DNA agarose gel electrophoresis. Microscopic analysis results showed that 15, 20 or 30 Gy groups displayed significantly apoptosis at 4 hour and 1 day after radiosurgery treatment compared to control and 40 Gy groups ( P <0.01). This result corresponds completely to DNA agarose gel electrophoresis, showing the “Ladder pattern” clearly within 1 day after SRS treatment in 15, 20 or 30 Gy groups, whereas the 40 Gy group was vaguely. The later group showed more necrosis than apoptosis. We find that this new technique has its unique preciseness to identify apoptotic cells and that it makes it easy to distinguish apoptotic cells from other cells. These results confirm that the apoptotic mode of cell death and necrosis may represent the response in this X knife treated rat C6 glioma model.