结肠癌细胞株SW480中CD133^+的分选及Bmi-1基因的表达

Isolation of CD133^+ and Expression of Bmi-1 Gene in Colon Cancer Cell Line SW480

目的:观察结肠癌细胞株SW480中CD133+和CD133-细胞的肿瘤干细胞样生物学特性,并分析CD133+和CD133-细胞中Bmi-1基因的表达量的差异。方法:采用流式细胞仪分选出CD133+和CD133-细胞,观察对比CD133+和CD133-细胞体外成球能力及增殖能力。用Real-time PCR检测CD133+和CD133-细胞中Bmi-1基因的表达量。结果:(1)SW480细胞中CD133+细胞所占比例为7.02%。(2)CD133+细胞体外无血清培养4 d后可成球且速度生长;CD133-细胞在干细胞培养基中不能形成细胞球,但在含血清的培养基中能贴壁分化,连续传代。无血清培养基中,CD133+细胞增殖能力强于CD133-细胞。(3)Bmi-1 m RNA在CD133+细胞的中表达显著高于CD133-细胞。结论:结肠癌细胞株SW480中CD133+所占比例很少,但其增殖能力强,Bmi-1 m RNA在CD133+细胞的中高表达,可能与肿瘤的发生发展有关。

Objective：To observe the cancer stem cell like characteristics of CD133＋ and CD133- in colon cancer cell line SW480,and to analyze the differences of expressions of Bmi-1 gene in CD133＋ and CD133- cells.Method：CD133＋ and CD133- cells were sorted by flow cytometry,the abilities of sphere-forming and cell proliferation of CD133＋ and CD133- cells in vitro were observed.The expressions of Bmi-1 gene in CD133＋ and CD133- cells were detected by Real-time PCR.Result：（1）CD133＋ cells accounted for 7.02% in SW480.（2）CD133＋ cells were formed spheres within 4 culture days and grow fast in vitro.CD133-cells can not formed spheres,but can adhered and differentiated in medium with serum.In serum-free medium,the abilities of proliferation in CD133＋ cells were bigger than those in CD133 cells.（3）The expressions of Bmi-1 mRNA in CD133＋ cells were significantly higher than those of CD133- cells.Conclusion：The CD133＋ cells account for a little proportion in SW480,but have the higher abilities of proliferation.Bmi-1 mRNA express highly in CD133＋ cells,may be related to the carcinogenesis.