全反式维甲酸对白血病NB4细胞PRAM蛋白的影响

目的:探讨在NB4细胞增殖过程中PRAM蛋白表达情况,并且用全反式维甲酸（ATRA）进行干扰,观察其对PRAM蛋白的影响。方法:①细胞增殖抑制实验:体外培养NB4细胞共5天,用台盼蓝染色法筛选ATRA有效干预浓度后,选取ATRA(1×10^-6mol/L)为目的干预浓度。②Western blot:ATRA(1×10^-6mol/L)持续干扰NB4细胞1、2、3天后检测PRAM蛋白的相对表达量。结果:①与对照组比较,4种浓度ATRA组细胞与NB4细胞的增殖率呈量效与时效关系;浓度越大,抑制率越高;于培养第4天出现最强抑制。②选取1×10^-6mol/L ATRA干扰NB4细胞共3天,对照组及ATRA组PRAM蛋白的表达在时间上有规律性:第2天表达最强烈。③1×10^-6mol/L ATRA使PRAM蛋白在第2天的相对表达量较对照组低（P<0.05）。④1×10^-6mol/l ATRA使NB4细胞PRAM蛋白在第2天出现最大表达量,同时该组细胞出现生长抑制。结论:ATRA能通过PRAM位点来达到抑制APL增殖分化的目的。

EXPRESSION OF PRAM PROTEIN IN MYELOID LEUKEMIA NB4 CELLS INFLUENCED BY ATRA

Objective:To discuss the expression of protein PRAM（PML-RARαtarget gene encoding an Adaptor Molecule,PRAM） in myeloid leukemia cells NB4 influenced by ATRA.Methods:NB4 cell line was cultured in 4 different concentrations of ATRA,and cells proliferation were detected.Then ATRA(1×10^-6mol/L) was chosen to add into cell culture,1,2,3 days later,PRAM protein were tested by Western blot.Results:①In the process’of NB4 cells cultured in vitro,the expression of PRAM protein was down-regulated by 10^-6mol/L ATRA compared with control group,especially on the 2nd day.②Protein PRAM expressed regularly,which was higher on the 2nd day and lower on the 3rd day.Conclusions:①1×10^-6mol/L ATRA can attenuate NB4 cells to mature.②ATRA leads to decreased expression of PRAM protein.It suggess that differentiation of acute promyelocytic leukemia cells is disrupted during transformation by PML-RARαand induced by ATRA signaling events.