三氧化二砷联合8-CPT-cAMP诱导维甲酸耐药早幼粒细胞白血病细胞分化的实验研究

In vitro study of the effects of arsenic trioxide combined with 8-CPT-cAMP on differentiation induction in retinoic acid resistant acute promyelocytic leukemia cells

目的 了解三氧化二砷 (As2 O3 )联合 8 对氯苯硫基环腺苷酸 (8 CPT cAMP)对维甲酸(RA)耐药的急性早幼粒细胞白血病 (APL)细胞的作用。方法 以RA耐药的APL细胞株NB4 R1和NB4 R2为模型 ,通过观察细胞生长、形态、表面分化抗原以及对四氮唑蓝的还原能力的改变来研究As2 O3 、8 CPT cAMP单独和联合对细胞增殖及分化的影响 ;并应用免疫荧光和Westernblot检测药物处理前后细胞内PML RARα融合蛋白以及细胞周期调控蛋白的变化。结果 低剂量As2 O3 (0 .2 5 μmol L)与 8 CPT cAMP(2 0 0 μmol L)可协同促进NB4 R1和NB4 R2细胞分化。 8 CPT cAMP可通过影响细胞周期调控蛋白E2F和P2 1的表达而抑制细胞增殖 ,并促进As2 O3 介导的PML RARα融合蛋白降解。结论 As2 O3 联合 8 CPT cAMP能够诱导RA耐药的APL细胞分化。

Objective To investigate the potential effects of arsenic trioxide (As 2O 3) combined with 8-(4-chlorophenylthio) adenosine 3′, 5′-cyclic monophosphate (8-CPT-cAMP) on the retinoic acid (RA)-resistant acute promyelocytic leukemia (APL) cells. Methods The RA resistant APL cell lines NB4-R1 and NB4-R2 were used as in vitro models. The effect of As 2O 3 and/or 8-CPT-cAMP was evaluated according to cellular morphology, cell surface antigen and nitroblue-tetrazolium (NBT) assay. Meanwhile, immunofluorescence analysis and Western blot assay were used to detect the degradation of PML-RARα fusion protein and the change of several key cell cycle regulatory proteins in these cells before and after the treatment. Results Low dose of As 2O 3 (0.25?μmol/L) synergized with 8-CPT-cAMP (200?μmol/L) in inducing differentiation of NB4-R1 and NB4-R2 cells, while neither of these two drugs alone could induce differentiation of these cells. In addition, 8-CPT-cAMP was able to inhibit the cell growth by modulating the expression of some important cell cycle regulators and to facilitate the As 2O 3-mediated degradation of PML-RARα fusion protein. Conclusions As 2O 3 combined with 8-CPT-cAMP could induce differentiation of RA-resistant APL cells.