摘要Objective To investigate the effects of all-trans retinoic acid(ATRA) on the expression of NANOG in glioma cell lines.Methods Each cell line was divided into the experimental group which was treated with ATRA for 5 days,and the control group which was cultured normally without ATRA treatment. Immunocytochemistry and RT-PCR were adopted to detect the expression of NANOG at protein and mRNA level among the three kinds of cell lines. Results Positive rates of NANOG protein in glioma cell lines SHG-44,U87 MG and U251 in control groups were (65.5±3.0)%,(64.8±8.0)% and (64.5±1.2)%, respectively, and the difference was not statistically significant(F=0.190,P=0.829). NANOG mRNA of the three cell lines in the relative content were 0.636 8±0.039 9, 0.642 1±0.063 7, 0.651 6±0.044 4，and the difference was not statistically significant(F=0.427,P=0.662).However,5 days after application of ATRA-induced NANOG protein in the three cell lines,the positive rates of NANOG protein of experimental groups were (36.5±7.3)%,(35.5±7.9)%,(35.2±6.1)%,respectively,compared with the control groups,the differences were statistically significant (FSHG-44=259.1,FU87=129.5,FU251= 431.8,PSHG-44=0.0,PU87=0.0,PU251=0.0),and the relative level of NANOG mRNA in these groups were 0.458 3±0.079 1,0.255 1±0.079 3 and 0.333 1±0.054 0,respectively,compared with the control groups,the difference was significant(FSHG-44=77.8,FU87=277.9,FU251=398.1,PSHG-44=0.0,PU87=0.0,PU251=0.0).Conclusion NANOG which highly expressed in glioma cell line SHG-44,U87 MG and U251 can be reduced by ATRA.