摘要
目的 探讨全反式维甲酸（ATRA）促进结直肠癌肿瘤干细胞分化的作用及其机制.方法 采用磁珠分选法从结直肠癌细胞株SW620细胞中分选出CD133＋细胞,并用流式细胞仪检测1.0×10-6 mol/L ATRA处理3d后CD133＋细胞比例的变化.采用成球实验观察1.0×10-6 mol/LATRA对结直肠癌干细胞处理后自我更新能力的影响.采用Western blot法检测1.0×10-6 mol/LATRA处理后β-链蛋白（β-catenin）及其磷酸化水平的改变.结果 SW620细胞中CD133＋细胞富集肿瘤干细胞,CD133＋和CD133-细胞的成球率分别为（51.00±7.67）％和（4.58±2.52）％（P＜0.01）.ATRA能促进SW620细胞中CD133＋细胞分化为CD133-细胞,用1.0×10-6mol/L ATRA处理细胞后,CD133＋细胞的比例为（47.90 ±7.87）％,对照组CD133＋细胞的比例为（95.33±2.24）％（P＜0.01）.ATRA能抑制CD133＋细胞的自我更新能力,ATRA处理组成球率为（12.67±2.08）％,对照组成球率为（24.33±2.52）％（P＜0.01）.ATRA处理后CD133＋细胞β-catenin的41号苏氨酸/45号丝氨酸位点（Thr41/Ser45）的磷酸化增加,β-catenin表达降低.结论 ATRA能促进结直肠癌干细胞中β-catenin的Thr41/Ser45位点磷酸化,促进β-catenin降解,抑制Wnt/β-catenin通路,诱导其分化为非肿瘤干细胞并降低自我更新能力.
Objective To detect the promoting effects of all-trans retinoic acid （ATRA） on differentiation of cancer stem cells （CSCs） of colorectal cancer and the mechanism.Methods In order to enrich CSCs,magnetic activated cell sorting （MACS） was used to purify CD133 ＋ CSCs from SW620 cell line.The proportion of CD133 ＋ cells in purified CSCs was measured after treatment with 1.0 × 10-6 moL/L ATRA or dimethylsurfoxide （DMSO） for 3 days by flow cytometry.The inhibitory effect of self-renewing ability of CSCs induced by 1.0 × 10-6 mol/L ATRA was evaluated by sphere formation assay.Phosphorylation and degradation of β-catenin induced by 1.0 × 10-6 mol/L ATRA was confirmed by Western blotting.Results CD133 ＋ SW620 cells effectively enrich CSCs.The rate of tumor spheres of CD133 ＋ and CD133-cells was （51.00 ± 7.67） % and （4.58 ± 2.52） %,respectively （P 〈 0.01）.After treatment with 1.0 × 10-6 mol/L ATRA,the proportion of CD133 ＋ cells was （47.90 ±7.87）%,and that in the control group was （95.33 ± 2.24） %,respectively （P 〈 0.01）.Interestingly,the rate of tumor spheres was decreased from （53.66 ± 6.03） % to （19.33 ± 2.52） % （P 〈 0.01）.Western blotting indicated that ATRA induced degradation of β-catenin by Thr41/Ser45 phosphorylation.Conclusion ATRA induces differentiation of colorectal CSCs,and inhibits their self-renewing ability by suppression of Wnt/β-catenin pathway.
出处
《中华实验外科杂志》
CAS
CSCD
北大核心
2015年第4期705-707,共3页
Chinese Journal of Experimental Surgery
基金
湖北省自然科学基金资助项目（2013CFB133）
关键词
全反式维甲酸
结直肠癌
肿瘤干细胞
细胞分化
All-trans retinoic acid
Colorectal cancer
Cancer stem cells
Cell differentiation
