细胞周期抑制剂SNS-032对小鼠造血干细胞生物活性的影响研究

本研究旨在探讨SNS-032（C17H24N4O2S2）对小鼠骨髓造血干细胞（hematopoietic stem cells,HSC）细胞周期、凋亡、分化及自我更新的影响及其可能的相关机制。利用极限稀释实验检测SNS-032作用前后HSC自我更新的变化,用流式细胞术检测SNS-032作用前后小鼠骨髓细胞Lin-c-kit＋Sca-1＋及Lin-c-kit＋Sca-1-表型细胞的细胞周期及凋亡的变化,用实时定量PCR检测SNS-032作用前后细胞周期相关基因、凋亡相关基因及HSC自我更新相关基因mRNA表达量的水平。结果显示,SNS-032处理后,小鼠骨髓细胞中HSC的自我更新能力没有明显变化;加SNS-032处理后,小鼠骨髓细胞Lin-c-kit＋Sca-1＋表型细胞的细胞周期无统计学意义的变化（P〉0.05）,小鼠骨髓Lin-c-kit＋Sca-1-表型细胞的G1期细胞增多（P〈0.05）;小鼠骨髓细胞Lin-c-kit＋Sca-1＋表型细胞和Lin-c-kit＋Sca-1-表型细胞的细胞凋亡增多,与对照相比均无显著性差异（P〉0.05）。小鼠骨髓细胞经SNS-032处理后,HSC周期相关基因CDK1、CDK2、CDK7、p27的表达量均明显降低（P〈0.05）,而CDK4,CDK6,p21,p18,p19,p16的表达与对照组相比没有明显变化（P〉0.05）。凋亡相关基因Bcl-2、Bax、Puma和p53表达量与对照组相比没有明显区别（P〉0.05）,与干细胞自我更新相关的基因中Bim,Sall4,Notch1表达量升高,但与对照组相比没有显著性差异（P〉0.05）。结论：SNS-032没有明显的抑制正常造血干细胞自我更新、分化作用,而且SNS-032没有明显的诱导正常造血干、祖细胞的凋亡作用。

Effect of SNS-032 on Biological Activity of Hematopoietic Stem Cells in Mice

This study was aimed to investigate the effect of SNS-032 （C17H24N402S2 ） on cell cycle, apoptosis, dif- ferentiation and self-renewal of hematopoietic stem cells （HSC） in mice. The self-renewal capability of bone marrow cells was measured by cobblestone forming cell test. The expressions of self-renewal regulation genes, cell cycle-related genes,apoptosis-related genes were measured by real-time PCR. The cell cycle status and apoptosis of HSC and HPC were detected by flow cytometry. The results showed that there was no significant difference of the frequency of HSC be- tween SNS-032 and control group. The expressions of CDK1, CDK2, CDK7 and p27 decreased in HSC （ P 〈 0.05 ） while the expressions of CDK4, CDK6, p21, p18, p19, Bcl-2, Bax, Puma, p53 , Biml , Sail4 and Notchl showed no difference between SNS-032 group and control group （ P 〉 0.05 ）. The fraction of viable HSC in each phase of cell cycle remained unchanged after the treatment of SNS-032 （ P 〉 0.05 ）. Furthermore, there was no statistical difference in the apoptotic fractions between control and drug-treated groups（ P 〉 0.05 ）. It is concluded that SNS-032 induce apoptosis of cancer cells. Interestingly, SNS-032 has no significant inhibitory effect on self-renewal and differentiation of normal HSC, as well as no obvious effect inducing apoptosis of normal HSC and HPC.