目的探讨小分子干扰RNA(si RNA)靶向沉默CDX2基因后对白血病细胞K562增殖、凋亡的影响,并检测BCR-ABL及相关凋亡蛋白表达量的变化,探讨其可能的作用机制。方法根据前期实验结果,成功筛选出能够特异性有效靶向沉默CDX2基因的si RNA序列(C...目的探讨小分子干扰RNA(si RNA)靶向沉默CDX2基因后对白血病细胞K562增殖、凋亡的影响,并检测BCR-ABL及相关凋亡蛋白表达量的变化,探讨其可能的作用机制。方法根据前期实验结果,成功筛选出能够特异性有效靶向沉默CDX2基因的si RNA序列(CDX2-si RNA)和相应的阴性对照序列(CDX2-si RNA-NC),应用罗氏X-treme GENE HP DNA Transfection Reagent转染K562细胞,流式细胞术检测CDX2沉默表达后对K562细胞凋亡的影响;RT-PCR法和Western Blot法分别检测BCR-ABL、Caspase-9、Bax m RNA和蛋白表达量变化。结果 MTT及流式细胞术检测显示,CDX2沉默表达后,K562细胞增殖能力减弱,凋亡率明显增加;RT-PCR和Western Blot显示,与正常细胞组和CDX2-si RNA-NC组相比,CDX2沉默表达后,CDX2-si RNA组的BCR-ABL m RNA和蛋白表达量明显降低,Caspase-9、Bax m RNA和蛋白表达量明显升高(均P<0.05)。结论 CDX2-si RNA能够明显促进白血病细胞K562凋亡,其机制可能与其抑制BCR-ABL表达,增强Caspase-9、Bax的活性有关。展开更多
study the effect of all trans retinoic acid (ATRA) and arsenic trioxide (As 2O 3) on tissue factor (TF) expression and procoagulant activity (PCA) of acute promyelocytic leukemia (APL) cells in vivo and in vitro Metho...study the effect of all trans retinoic acid (ATRA) and arsenic trioxide (As 2O 3) on tissue factor (TF) expression and procoagulant activity (PCA) of acute promyelocytic leukemia (APL) cells in vivo and in vitro Methods PCA from freshly isolated APL blasts from APL patients treated with ATRA or As 2O 3 was detected using a one stage clotting assay TF antigen was detected by ELISA and TF mRNA by RT PCR The maturation sensitive (NB4) or resistant subclones (NB4 R1) of the promyelocytic NB4 cell line, as well as U937 cells infected with pMSCV PML RARa treated with or without ATRA or As 2O 3, were also examined Results Both ATRA and As 2O 3 can down regulate the TF antigen, its mRNA transcription and membrane PCA of APL cells in vivo and in vitro, in a time dependent manner The TF antigen level in PML RARa+ U937 cells was significantly higher than that in U937 cells infected with retrovirus vector Both ATRA and As 2O 3 can also down regulate the TF antigen in U937 cells transfected with or without PML RARa Conclusion Tissue factor expression and PCA in APL cells may be down regulated by ATRA and As 2O 3 By down regulating TF expression, As 2O 3 might also be used to improve the DIC related hemorrhage in APL Our data indicate that elevated TF antigen in PML RARa+ U937 may be related to the fusion protein PML RARa The down regulating effect of ATRA and As 2O 3 on TF expression in U937 cells might not involve this fusion展开更多
文摘目的探讨小分子干扰RNA(si RNA)靶向沉默CDX2基因后对白血病细胞K562增殖、凋亡的影响,并检测BCR-ABL及相关凋亡蛋白表达量的变化,探讨其可能的作用机制。方法根据前期实验结果,成功筛选出能够特异性有效靶向沉默CDX2基因的si RNA序列(CDX2-si RNA)和相应的阴性对照序列(CDX2-si RNA-NC),应用罗氏X-treme GENE HP DNA Transfection Reagent转染K562细胞,流式细胞术检测CDX2沉默表达后对K562细胞凋亡的影响;RT-PCR法和Western Blot法分别检测BCR-ABL、Caspase-9、Bax m RNA和蛋白表达量变化。结果 MTT及流式细胞术检测显示,CDX2沉默表达后,K562细胞增殖能力减弱,凋亡率明显增加;RT-PCR和Western Blot显示,与正常细胞组和CDX2-si RNA-NC组相比,CDX2沉默表达后,CDX2-si RNA组的BCR-ABL m RNA和蛋白表达量明显降低,Caspase-9、Bax m RNA和蛋白表达量明显升高(均P<0.05)。结论 CDX2-si RNA能够明显促进白血病细胞K562凋亡,其机制可能与其抑制BCR-ABL表达,增强Caspase-9、Bax的活性有关。
文摘study the effect of all trans retinoic acid (ATRA) and arsenic trioxide (As 2O 3) on tissue factor (TF) expression and procoagulant activity (PCA) of acute promyelocytic leukemia (APL) cells in vivo and in vitro Methods PCA from freshly isolated APL blasts from APL patients treated with ATRA or As 2O 3 was detected using a one stage clotting assay TF antigen was detected by ELISA and TF mRNA by RT PCR The maturation sensitive (NB4) or resistant subclones (NB4 R1) of the promyelocytic NB4 cell line, as well as U937 cells infected with pMSCV PML RARa treated with or without ATRA or As 2O 3, were also examined Results Both ATRA and As 2O 3 can down regulate the TF antigen, its mRNA transcription and membrane PCA of APL cells in vivo and in vitro, in a time dependent manner The TF antigen level in PML RARa+ U937 cells was significantly higher than that in U937 cells infected with retrovirus vector Both ATRA and As 2O 3 can also down regulate the TF antigen in U937 cells transfected with or without PML RARa Conclusion Tissue factor expression and PCA in APL cells may be down regulated by ATRA and As 2O 3 By down regulating TF expression, As 2O 3 might also be used to improve the DIC related hemorrhage in APL Our data indicate that elevated TF antigen in PML RARa+ U937 may be related to the fusion protein PML RARa The down regulating effect of ATRA and As 2O 3 on TF expression in U937 cells might not involve this fusion
