CD133+干细胞在胰腺癌放疗耐受中的作用

The role of CD133+ stem cells in radiotherapy resistance of pancreatic cancer

目的研究肿瘤干细胞在胰腺癌放疗耐受中的作用。方法应用磁珠分选法分选CD133+胰腺癌干细胞,首先用MTT法和流式细胞仪观察放射线干预后胰腺癌不同细胞亚群的增殖活性及细胞凋亡;流式细胞仪、Western blot和qRT-PCR检测放射线干预后胰腺癌细胞CD133的表达变化;流式细胞仪观察不同细胞亚群的细胞周期分布。结果用放射线干预后,CD133+干细胞与未分选细胞及CD133-细胞相比,存活率最高、凋亡率最低,且胰腺癌细胞中CD133+干细胞比例上升,CD133蛋白和RNA表达均上调;CD133+干细胞与未分选细胞和CD133-细胞相比,G 0/G 1期比例最高,且差异具有统计学意义。结论CD133+胰腺癌干细胞是导致胰腺癌细胞放疗耐受的重要原因之一,而G 0/G 1期比例高可能是其机制之一。

Objective To study the role of pancreatic cancer stem cells in radiotherapy resistance of pancreatic cancer.Methods CD133+pancreatic cancer stem cells were obtained by using magnetic cell sorting.MTT and flow cytometry were used to observe the proliferation activity and apoptosis of different cell subsets of pancreatic cancer after radiation treatment.Then flow cytometry,Western blot and qRT-PCR were used to observe the expression changes of CD133 in pancreatic cancer cells after radiation treatment.Finally,the cell cycle distribution of different subgroup cells was observed by flow cytometry.Results Compared with unselected cells and CD133-cells,CD133+stem cells had the highest survival rate and the lowest apoptosis rate after radiation treatment.The proportion of CD133+stem cells increased and the expressions of CD133 protein and RNA increased in pancreatic cancer cells.CD133+stem cells had the highest ratio of G 0/G 1 phase compared with unsorted cells and CD133-cells,and the difference was statistically significant.Conclusion CD133+pancreatic cancer stem cells are one of the important causes of radiotherapy resistance in pancreatic cancer cells,and the increased proportion of G 0/G 1 phase may be one of the mechanisms.